A wireless communication method includes receiving, by a first wireless device during a training phase, reference tones using a first number of resource elements from a transmitter of a second wireless device, wherein the first wireless device comprises multiple receiving antennas, estimating, by the first wireless device, from the receiving the reference tones, a second order statistics of wireless channels between the multiple receiving antennas and the transmitter of the second wireless device, and performing channel estimation, during an operational phase subsequent to the training phase, using the second order statistics and reference tones received on a second number of resource elements, wherein the second number is less than the first number.
Methods, systems and devices for fractional cooperative multipoint network operation are described. One example method for wireless communication includes determining, by a network device, a cooperative multipoint (COMP) management status of wireless devices served by the network device, and providing, by the network device, wireless connectivity to the one or more wireless devices, wherein the network device jointly manages transmission resources for a first wireless device due to the COMP management status being a joint COMP status and the network device locally manages transmission resources for a second wireless device due to the COMP management status being a local COMP status.
Methods, systems, and devices for spectral sharing wireless systems, wherein multiple user devices share time and frequency resources for uplink and/or downlink transmissions, are described. One example method includes transmitting transmission symbols from the network station to at least one user device by processing through a first precoder and a pre-compensation stage, wherein the pre-compensation stage is selected to have the transmission symbols receivable at the at least one user device to appear as if the transmission symbols are processed by a second precoder different from the first precoder.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
A network transceiver apparatus is configured to allow simultaneous carriage of multiple network operators' entire cellular spectrum traffic to and from wireless user devices using a wideband antenna. The wideband antenna provides a spherical radiation pattern that allows the operation of the wideband antenna at a power that is at least 8 dB below conventional techniques. An example wireless communication method, in accordance with the disclosed embodiments, includes configuring a transceiver apparatus comprising a transmit chain and a receive chain, and providing wireless connectivity to multiple user devices operating in multiple network operators' networks in a multi-user multi-input multi-output configuration.
Methods, systems, and devices for channel calibration based on parameter perturbation are described. An example wireless communication method includes determining a current precoding operational point (OP) for transmissions to one or more wireless devices, performing a first (and second) set of measurement transmissions having a first (and second) precoding OP that is positively (negatively) perturbed from the current precoding OP by a first (second) perturbation value, and estimating, based on one or more feedback signals received from the one or more wireless devices in response to the first set of measurement transmissions and the second set of measurement transmissions, a next precoding OP to be used for transmissions from the network device to the one or more wireless devices.
Methods, systems and devices for wireless communication are described. One example method includes generating a transmission waveform comprising modulated data symbols carrying information bits, wherein the modulated data symbols are organized in a number of data frames along a delay-Doppler grid comprising N Doppler elements and M delay elements, where N and M are positive integers, and transmitting the transmission waveform using frequency and time resources wherein: (a) a reduced power frequency portion of the frequency resources is configured such that a power of the transmission waveform in the reduced power frequency portion is below a first threshold, or (b) a reduced power time portion of the time resources is configured such that the power of the transmission waveform in the reduced power time portion is below a second threshold.
Methods, systems and devices for massive cooperative multipoint network operation are described. One example method for wireless communication includes transmitting, by a network node serving a plurality of mobile devices in a surrounding area, channel condition information and scheduling information for one or more of the plurality of mobile devices to a network-side server, receiving, by the network node from the network-side server, control information for scheduling transmissions to or from each of the one or more of the plurality of mobile devices, and controlling, by the network node and based on the control information, a communication to or from the one or more of the plurality of mobile devices at a future time or a different frequency band or a different spatial direction.
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
Computerized wireless transmitter/receiver system that automatically uses combinations of various methods, including transmitting data symbols by weighing or modulating a family of time shifted and frequency shifted waveforms bursts, pilot symbol methods, error detection methods, MIMO methods, and other methods, to automatically determine the structure of a data channel, and automatically compensate for signal distortions caused by various structural aspects of the data channel, as well as changes in channel structure. Often the data channel is a two or three dimensional space in which various wireless transmitters, receivers and signal reflectors are moving. The invention's modulation methods detect locations and speeds of various reflectors and other channel impairments. Error detection schemes, variation of modulation methods, and MIMO techniques further detect and compensate for impairments. The invention can automatically optimize its operational parameters, and produce a deterministic non-fading signal in environments in which other methods would likely degrade.
Methods, systems and devices for wireless communication, which include localization and auto-calibration, are described. One example method includes receiving, at a wireless device, signal transmissions from one or more network devices, and generating, by processing the signal transmissions, a feedback signal for antenna calibration of the one or more network devices. In some embodiments, the antenna calibration is used for performing device localization and feature map generation that is subsequently used for scheduling transmissions in a wireless network.
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
10.
NETWORK-SIDE COORDINATION OF MULTI-USER MULTIPLE-INPUT MULTIPLE-OUTPUT FUNCTIONALITY
Methods, systems, and devices for operating a wireless communication network are described. One example method includes configuring a multi-user multi-input multi-output (MU-MIMO) control function in a wireless network comprising multiple network functions, where the MU-MIMO control function provides an MU-MIMO capability to the wireless network using which the wireless network provides wireless connectivity to user devices using an MU-MIMO configuration.
Methods, apparatus and systems for wireless communication are described. One example method includes estimating, based on channel quality information for a first communication channel during a first time interval, a predicted quality of a second communication channel during a second time interval that is a latency interval after the first time interval and using the predicted quality for processing transmissions on the second communication channel during the second time interval.
An Orthogonal Time Frequency Space Modulation (OTFS) modulation scheme achieving multiple access by multiplexing multiple signals at the transmitter-side performs allocation of transmission resources to a first signal and a second signal, combining and converting to a transmission format via OTFS modulation and transmitting the signal over a communication channel. At the receiver, multiplexed signals are recovered using orthogonality property of the basis functions used for the multiplexing at the transmitter.
H04L 1/00 - Arrangements for detecting or preventing errors in the information received
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
H04L 5/00 - Arrangements affording multiple use of the transmission path
H04L 25/03 - Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
Techniques for performing channel estimation in an orthogonal time, frequency and space (OTFS) communication system include receiving a wireless signal comprising a data signal portion and a pilot signal portion in which the pilot signal portion includes multiple pilot signals multiplexed together in the OTFS domain, performing two-dimensional channel estimation in a time-frequency domain based on a minimum mean square error (MMSE) optimization criterion, and recovering information bits using a channel estimate obtained from the two-dimensional channel estimation.
A wireless communication device includes a feed port comprising multiple input feeds, a precoding subsystem that is electrically connected to the feed port; and an antenna subsystem electrically connected to the precoding subsystem. The antenna subsystem is configured to transmit an output signal of the precoding subsystem to multiple wireless stations using multiple beams. The precoding subsystem is configured to perform a precoding operation on an input signal from the feed port, wherein the precoding operation maximizes a desired signal level to interference ratio of transmissions to the multiple wireless stations.
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
H04B 7/0408 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas using two or more beams, i.e. beam diversity
H04L 5/00 - Arrangements affording multiple use of the transmission path
H04L 5/14 - Two-way operation using the same type of signal, i.e. duplex
15.
ORTHOGONAL TIME FREQUENCY SPACE SIGNAL COMMUNICATION USING PREDEFINED BASIS SIGNALS
Methods and systems for orthogonal time frequency space (OTFS) communication using predefined basis signals are described. An example digital communication method includes receiving a signal over a communication channel, determining an estimate of the communication channel from one or more pilot symbols in the signal transmission. Herein the one or more pilot symbols are assigned along a delay-Doppler resource grid. The method further includes equalizing non-pilot symbols in the signal transmission by rotating the estimate of the communication channel according to grid locations of the one or more pilot symbols along the delay-Doppler resource grid at other grid locations, and recovering data bits from the equalized non-pilot symbols.
H04L 1/20 - Arrangements for detecting or preventing errors in the information received using signal-quality detector
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Methods, systems and devices for distributed cooperative operation of wireless cells based on sparse channel representations are described. One example method includes providing, using a server, seamless wireless connectivity in an area in which a plurality of network nodes are organized as clusters, where each network node is configured to provide wireless connectivity via N angular sectors covering a surrounding area, where N is an integer and wherein angular sectors of the plurality of network nodes collectively cover the area; controlling, by the server, network nodes in a cluster to collect channel condition information for the N angular sectors and communicate the channel condition information to the network-side server, and operating the server to use the channel condition information collected from the network nodes in the cluster to control communication for the network nodes in the cluster at a different time or a different frequency or a different spatial direction.
Methods, systems and devices for wireless communication are described. One example method includes performing a first mapping in which information bits are mapped to transmission resources in a first portion of a two-dimensional delay-Doppler grid. Herein, the two-dimensional delay-Doppler grid comprises N Doppler elements and M delay elements, where N and M are positive integers. The method further includes performing a second mapping in which a reference signal is mapped to transmission resources in a second portion of the two-dimensional delay-Doppler grid, and generating a transmission waveform from a signal combination of an output of the first mapping and an output of the second mapping. The transmission waveform corresponds to an output of an orthogonal time frequency space (OTFS) waveform of the signal combination, and at least the output of the second mapping undergoes a time domain spreading.
A method for modulating data for transmission within a communication system. The method includes establishing a time-frequency shifting matrix of dimension N×N, wherein N is greater than one. The method further includes combining the time-frequency shifting matrix with a data frame to provide an intermediate data frame. A transformed data matrix is provided by permuting elements of the intermediate data frame. A modulated signal is generated in accordance with elements of the transformed data matrix.
A wireless communication method includes receiving, by a first wireless device during a training phase, reference tones using a first number of resource elements from a transmitter of a second wireless device, wherein the first wireless device comprises multiple receiving antennas, estimating, by the first wireless device, from the receiving the reference tones, a second order statistics of wireless channels between the multiple receiving antennas and the transmitter of the second wireless device, and performing channel estimation, during an operational phase subsequent to the training phase, using the second order statistics and reference tones received on a second number of resource elements, wherein the second number is less than the first number.
Methods, systems and devices for wireless communication are described. One example method includes mapping information bits to transmission resources in a two-dimensional delay-Doppler grid In this example, the two-dimensional delay-Doppler grid includes N Doppler elements along a Doppler dimension and M delay elements along a delay dimension, and N and M are positive integers. The example method continues with converting a result of the mapping to a signal waveform, and generating an orthogonal time frequency space (OTFS) waveform by spreading the signal waveform using a spreading scheme. In some examples, the signal waveform includes an ultra-wide band (UWB) waveform.
Methods, systems and devices for wireless communication are described. One method includes obtaining a two-dimensional delay-Doppler representation of a received wireless signal that is received over a wireless channel, determining an estimated channel response of the wireless channel from a portion of the delay-Doppler grid corresponding to a channel estimation portion, performing, using the estimated channel response, channel equalization in the delay-Doppler domain, generating, based on the channel equalization, a posteriori probability estimates of data symbols in the received wireless signal, wherein the a posteriori probability estimates are generated based on a priori feedback that is generated using an iterative process and further processing the a posteriori probability estimates of data symbols to recover information bits from the received wireless signal.
Orthogonal Time Frequency Space (OTFS) is a novel modulation scheme with significant benefits for 5G systems. The fundamental theory behind OTFS is presented in this paper as well as its benefits. We start with a mathematical description of the doubly fading delay-Doppler channel and develop a modulation that is tailored to this channel. We model the time varying delay-Doppler channel in the time-frequency domain and derive a new domain (the OTFS domain) where we show that the channel is transformed to a time invariant one and all symbols see the same SNR. We explore aspects of the modulation like delay and Doppler resolution, and address design and implementation issues like multiplexing multiple users and evaluating complexity. Finally we present some performance results where we demonstrate the superiority of OTFS.
Techniques for wireless networking that include transmission and reception of signals using orthogonal time frequency space (OTFS) modulation techniques are disclosed. For example, a wireless access point may communicate with a station using OFDM modulated WiFi (OFDM-WiFi) at one time and using OTFS modulated WiFi (OTFS-WiFi) at another time. The OTFS-WiFi may provide improved throughput and coverage over OFDM-WiFi in static and mobile environments.
H04W 4/80 - Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
H04L 5/00 - Arrangements affording multiple use of the transmission path
An airborne device carrying an RF-head platform is disclosed. The device includes one or more antennas configured to transmit (Tx) wireless signals to and receive (Rx) wireless signals from a baseband unit of a ground station by at least one laser communications link and one or more RF heads coupled to the one or more antennas. A respective RF head may be configured to convert Rx RF signals received from at least one user equipment (UE) into Rx digitized-waveform data, to transmit the Rx digitized-waveform data to the baseband unit of the ground station over the at least one laser communications link, to convert Tx digitized-waveform data received from the baseband unit of the ground station over the at least one laser communications link into Tx RF signals, and to transmit the Tx RF signals to the at least one UE.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Device, methods, and systems for implementing aspects of orthogonal time frequency space (OTFS) modulation in wireless systems are described. In an aspect, the device may include a surface of an object for receiving an electromagnetic signal. The surface may be structured to perform a non-electrical function for the object. The surface may generate an electrical signal from an electromagnetic signal. The electromagnetic signal may be received from a transmitter. The transmitter may map digital data to a digital amplitude modulation constellation in a time-frequency space. The digital amplitude modulation constellation may be mapped to a delay-Doppler domain and the transmitter may transmit to the surface according to an orthogonal time frequency space modulation signal scheme. The apparatus may further include a demodulator to demodulate the electrical signal to determine digital data.
A method of wireless communication includes performing a first measurement of a wavefront received at a first antenna of a base station configured to provide a wireless communication access to user devices in a coverage area, performing a second measurement of the wavefront received at a second antenna of the base station, wherein the first antenna and the second antenna are separated by a separation distance along a direction, deriving a compensation factor from the first measurement and the second measurement, wherein the compensation factor is used for estimating an estimated angle of arrival (AOA) and performing the subsequent communication by applying the compensation factor to an outgoing or an incoming signal waveform to or from a user device.
G01S 1/14 - Systems for determining direction or position line using amplitude comparison of signals transmitted simultaneously from antennas or antenna systems having differently-oriented overlapping directivity-characteristics
G01S 1/02 - Beacons or beacon systems transmitting signals having a characteristic or characteristics capable of being detected by non-directional receivers and defining directions, positions, or position lines fixed relatively to the beacon transmittersReceivers co-operating therewith using radio waves
G01S 3/16 - Systems for determining direction or deviation from predetermined direction using amplitude comparison of signals derived sequentially from receiving antennas or antenna systems having differently-oriented directivity characteristics or from an antenna system having periodically-varied orientation of directivity characteristic
H01Q 3/00 - Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
H04B 7/08 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
Methods, systems, and devices for spectral sharing wireless systems, wherein multiple user devices share time and frequency resources for uplink and/or downlink transmissions, are described. One example wireless communication system includes a network station, and multiple user devices, wherein data transmissions over the same time and frequency resources are shared between multiple user devices, in downlink and/or uplink, using spatial user device separation that is dynamically computed by the network station, and where the network station derives spatial user device separation based on uplink channel measurements.
A method of wireless communication performed by a base station includes grouping a plurality of wireless devices associated with a coverage area of the base station into multiple spatial groups, and configuring the wireless devices in each spatial group to use overlapping time-frequency transmission resources for uplink (UL) data transmissions to the base station. The method also includes scheduling, on a same set of time-frequency transmission resources, demodulation reference signal (DMRS) transmissions by the wireless devices in a respective spatial group of the multiple spatial groups. In various aspects, the multiple spatial groups are determined based on respective estimated angles of arrival of the plurality of wireless devices associated with the coverage area of the base station. In some instances, each of the wireless devices in the respective spatial group uses the same antenna ports as the other wireless devices in the respective spatial group for the DMRS transmissions.
H04B 7/04 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
Methods, systems and devices for spatial multiplexing of different radio technologies are described. An example method for wireless communication includes configuring abase station of a fifth generation new radio (5G NR) radio technology cell to perform transmissions in a network according to a set of compatibility rules that allow a backward compatible operation of the base station with a 4th generation Long Term Evolution (4G LTE) radio technology, and performing transmissions or receptions in the 5G NR cell according to the configuring such that the backward compatible operation is achieved based on orthogonality in a spatial domain between transmissions or receptions in the 5G NR cell and the 4G LTE radio technology.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
A wireless communication method includes determining, by a network device, uplink power allocations assigned to each user device of multiple user devices; estimating a channel response for each user device of multiple user devices based on a corresponding uplink reference signal transmission received from the each user device; computing, for the each user device, a covariance matrix based on a corresponding channel response, determining a maximum eigenvector of an uplink signal to interference and noise ratio (SINR) matrix for the each user device; computing, from the uplink SINR matrix, a downlink cross-interference matrix for the each user device; selecting, from the downlink cross-interference matrix for the each user device, a selected vector that maximizes a selected criterion for the each user device; and determining, from the selected vectors of the multiple user devices, a downlink power allocation for the each user device of multiple user devices.
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
A method for modulating data for transmission within a communication system. The method includes establishing a time-frequency shifting matrix of dimension N×N, wherein N is greater than one. The method further includes combining the time-frequency shifting matrix with a data frame to provide an intermediate data frame. A transformed data matrix is provided by permuting elements of the intermediate data frame. A modulated signal is generated in accordance with elements of the transformed data matrix.
Methods, systems and devices for wireless communication are described. One example method includes performing, by a network device, gain, phase and timing imbalance calibrations of multiple wireless devices in a wireless network, estimating, by the network device, angles of arrivals of the multiple wireless devices, determining wireless device grouping based on geometric properties including angels of arrivals of the multiple wireless devices, scheduling data collection from the multiple wireless devices based on the geometric properties, and simultaneously scheduling groups of wireless devices from the multiple wireless devices for data transmission or reception based on the grouping.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
H04B 7/04 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas
33.
Communication techniques using quasi-static properties of wireless channels
Methods, devices, and systems for communication techniques that use the quasi-static properties of wireless channels are described. One example method to improve communication performance includes receiving a set of pilots over a transmission channel between the wireless communication apparatus and a far-end communication apparatus, the transmission channel comprising a first portion that is time-invariant and a second portion that is time-variant, processing the received set of pilots to generate an estimate of the first portion, processing the received set of pilots to generate an estimate of the second portion, and performing a communication based on a channel state information that is a weighted combination of a first term based on the estimate of the first portion and a second term based on the estimate of the second portion.
H04W 72/566 - Allocation or scheduling criteria for wireless resources based on priority criteria of the information or information source or recipient
34.
Method and apparatus for determining a channel state of an impaired data channel
Fiber, cable, and wireless data channels are typically impaired by reflectors and other imperfections, producing a channel state with echoes and frequency shifts in data waveforms. Here, methods of using pilot symbol waveform bursts to automatically produce a detailed 2D model of the channel state are presented. This 2D channel state can then be used to optimize data transmission. For wireless data channels, an even more detailed 2D model of channel state can be produced by using polarization and multiple antennas in the process. Once 2D channel states are known, the system turns imperfect data channels from a liability to an advantage by using channel imperfections to boost data transmission rates. The methods can be used to improve legacy data transmission modes in multiple types of media, and are particularly useful for producing new types of robust and high capacity wireless communications using non-legacy data transmission methods as well.
Methods, systems and devices for wireless communication are described. An example method for wireless communication includes controlling a sweep of channel estimation transmissions across a two-dimensional antenna array comprising N horizontal antennas and M vertical antennas according to an operational condition in a wireless communication network. In one example, a pattern used for the sweep sweeps across horizontal antennas followed by a sweep across vertical antennas. In another example, a pattern used for the sweep sweeps across vertical antennas followed by a sweep across horizontal antennas.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Methods, systems and devices for wireless communication, which include localization and auto-calibration, are described. One example method includes receiving, at a wireless device, signal transmissions from one or more network devices, and generating, by processing the signal transmissions, a feedback signal for antenna calibration of the one or more network devices. In some embodiments, the antenna calibration is used for performing device localization and feature map generation that is subsequently used for scheduling transmissions in a wireless network.
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
37.
SCHEDULING AND RETRANSMISSION IN CENTRAL UNITS AND DISTRIBUTED UNITS
Methods, systems and devices for wireless communication are described. One example method includes determining, using resources in a wireless network, a schedule of transmissions between the wireless network and one or more user devices, and controlling the transmissions according to the schedule. The resources are distributed between a central unit (CU) and a distributed unit (DU) according to a resource partitioning scheme. The DU is configured to handle a first set of protocol layers of a communication protocol stack implemented in the wireless network according to a layer partitioning scheme and the CU is configured to handle a second set of protocol layers of the communication protocol stack according to the layer partitioning scheme. The first set of protocol layers excludes an upper medium access control (MAC) layer. The second set of protocol layers excludes a physical layer.
A fixed wireless access system is implemented using orthogonal time frequency space multiplexing (OTFS). Data transmissions to/from different devices share transmission resources using—delay Doppler multiplexing, time-frequency multiplexing, multiplexing at stream and/or layer level, and angular multiplexing. Time-frequency multiplexing is achieved by dividing the time-frequency plan into subgrids, with the subsampled time frequency grid being used to carry the OTFS data. Antenna implementations include a hemispherical antenna with multiple antenna elements arranged in an array to achieve multiplexing.
H04L 5/00 - Arrangements affording multiple use of the transmission path
H01Q 21/24 - Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Wireless communication transmission and reception techniques are described. At transmitter, source data bits are modulated into a number Nd of constellation symbols. An invertible transform is applied to the constellation symbols, thereby resulting in mapping the transformed symbols into Nd elements in the time-frequency grid. A signal resulting from the invertible transform is transmitted over a communication channel.
Computerized wireless transmitter/receiver system that automatically uses combinations of various methods, including transmitting data symbols by weighing or modulating a family of time shifted and frequency shifted waveforms bursts, pilot symbol methods, error detection methods, MIMO methods, and other methods, to automatically determine the structure of a data channel, and automatically compensate for signal distortions caused by various structural aspects of the data channel, as well as changes in channel structure. Often the data channel is a two or three dimensional space in which various wireless transmitters, receivers and signal reflectors are moving. The invention's modulation methods detect locations and speeds of various reflectors and other channel impairments. Error detection schemes, variation of modulation methods, and MIMO techniques further detect and compensate for impairments. The invention can automatically optimize its operational parameters, and produce a deterministic non-fading signal in environments in which other methods would likely degrade.
An airborne RF-head platform system and method. Here, much of the computational burden of transmitting and receiving wireless RF waveforms is shifted from the airborne platform to a ground baseband unit (BBU). The airborne platform, which will often be a high altitude balloon or drone type platform, generally comprises one or more remote radio heads, configured with antennas, A/D and D/A converters, frequency converters, RF amplifiers, and the like. The airborne platform communicates with the ground baseband units either directly via a laser communications link, or indirectly through another airborne relay platform. The airborne RF-head communicates via various wireless protocols to various user equipment such as smartphones by using the BBU and the laser communications link to precisely control the function of the airborne A/D and D/A converters and antennas. This system reduces the power needs, weight, and cost of the airborne platform, and also improves operational flexibility.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Methods, systems and devices for wireless communication are described. One example method includes performing a first mapping in which information bits are mapped to transmission resources in a first portion of a two-dimensional delay-Doppler grid. Herein, the two-dimensional delay-Doppler grid comprises N Doppler elements and M delay elements, where N and M are positive integers. The method further includes performing a second mapping in which a reference signal is mapped to transmission resources in a second portion of the two-dimensional delay-Doppler grid, and generating a transmission waveform from a signal combination of an output of the first mapping and an output of the second mapping. The transmission waveform corresponds to an output of an orthogonal time frequency space (OTFS) waveform of the signal combination, and at least the output of the second mapping undergoes a time domain spreading.
Methods, apparatus and systems for wireless communication are described. One example method includes estimating, based on channel quality information for a first communication channel during a first time interval, a predicted quality of a second communication channel during a second time interval that is a latency interval after the first time interval and using the predicted quality for processing transmissions on the second communication channel during the second time interval.
Techniques for performing channel estimation in an orthogonal time, frequency and space (OTFS) communication system include receiving a wireless signal comprising a data signal portion and a pilot signal portion in which the pilot signal portion includes multiple pilot signals multiplexed together in the OTFS domain, performing two-dimensional channel estimation in a time-frequency domain based on a minimum mean square error (MMSE) optimization criterion, and recovering information bits using a channel estimate obtained from the two-dimensional channel estimation.
Methods, systems and devices for providing transmission resources that achieve transmission diversity while reducing pilot signal overhead are described. An exemplary wireless communication method may be implemented in a wireless communication system in which transmission resources are allocated on a per physical resource block (PRB) basis, where a PRB corresponds to a two dimensional resource pattern comprising a first number of subcarriers along a frequency dimension and a second number time slots along a time dimension. The method includes logically dividing subcarriers in each PRB into an integer number of sub-groups of sub-carriers, wherein the integer number is greater than one, allocating, to a transmission, transmission resources corresponding to one or more of the sub-groups of subcarriers, performing the transmission in the wireless communication system.
An airborne RF-head platform system and method. Here, much of the computational burden of transmitting and receiving wireless RF waveforms is shifted from the airborne platform to a ground baseband unit (BBU). The airborne platform, which will often be a high altitude balloon or drone type platform, generally comprises one or more remote radio heads, configured with antennas, A/D and D/A converters, frequency converters, RF amplifiers, and the like. The airborne platform communicates with the ground baseband units either directly via a laser communications link, or indirectly through another airborne relay platform. The airborne RF-head communicates via various wireless protocols to various user equipment such as smartphones by using the BBU and the laser communications link to precisely control the function of the airborne A/D and D/A converters and antennas. This system reduces the power needs, weight, and cost of the airborne platform, and also improves operational flexibility.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Co-existence between an Orthogonal Time Frequency Space (OTFS) modulation system and a Long Term Evolution (LTE) system is achieved by generating a number of transmission beams for a first group of user equipment operating using LTE, and a second group of user equipment operating using the OTFS protocol, and transmitting a first group of data packets formatted according to the LTE protocol to the first group of user equipment and a second group of data packets formatted according to the OTFS protocol to the second group of user equipment. The transmissions are performed by precoding and modulating the first group of data packets according to an LTE modulation scheme, and precoding and modulating the second group of data packets according to an OTFS modulation scheme.
H04W 4/06 - Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]Services to user groupsOne-way selective calling services
H04W 72/044 - Wireless resource allocation based on the type of the allocated resource
H04W 72/20 - Control channels or signalling for resource management
A wireless communication device includes a feed port comprising multiple input feeds, a precoding subsystem that is electrically connected to the feed port; and an antenna subsystem electrically connected to the precoding subsystem. The antenna subsystem is configured to transmit an output signal of the precoding subsystem to multiple wireless stations using multiple beams. The precoding subsystem is configured to perform a precoding operation on an input signal from the feed port, wherein the precoding operation maximizes a desired signal level to interference ratio of transmissions to the multiple wireless stations.
H04L 5/00 - Arrangements affording multiple use of the transmission path
H04B 7/0408 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas using two or more beams, i.e. beam diversity
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
H04L 5/14 - Two-way operation using the same type of signal, i.e. duplex
49.
ULTRA WIDE BAND SIGNALS USING ORTHOGONAL TIME FREQUENCY SPACE MODULATION
Methods, systems and devices for wireless communication are described. One example method includes mapping information bits to transmission resources in a two-dimensional delay-Doppler grid In this example, the two-dimensional delay-Doppler grid includes N Doppler elements along a Doppler dimension and M delay elements along a delay dimension, and N and M are positive integers. The example method continues with converting a result of the mapping to a signal waveform, and generating an orthogonal time frequency space (OTFS) waveform by spreading the signal waveform using a spreading scheme. In some examples, the signal waveform includes an ultra-wide band (UWB) waveform.
Methods, systems and devices for reciprocal geometric precoding are described. One example method includes determining, by a network device, an uplink channel state using reference signal transmissions received from multiple user devices, and generating a precoded transmission waveform for transmission to one or more of the multiple user devices by applying a precoding scheme that is based on the uplink channel state, wherein the uplink channel state completely defines the precoding scheme. In some embodiments, the reference signal transmissions and the precoded transmission waveform are multiplexed using either time-domain multiplexing or frequency-domain multiplexing.
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
Methods, systems and devices for wireless communication are described. One method includes obtaining a two-dimensional delay-Doppler representation of a received wireless signal that is received over a wireless channel, determining an estimated channel response of the wireless channel from a portion of the delay-Doppler grid corresponding to a channel estimation portion, performing, using the estimated channel response, channel equalization in the delay-Doppler domain, generating, based on the channel equalization, a posteriori probability estimates of data symbols in the received wireless signal, wherein the a posteriori probability estimates are generated based on a priori feedback that is generated using an iterative process and further processing the a posteriori probability estimates of data symbols to recover information bits from the received wireless signal.
Methods, systems, and devices for spectral sharing wireless systems, wherein multiple user devices share time and frequency resources for uplink and/or downlink transmissions, are described. One example method includes transmitting transmission symbols from the network station to at least one user device by processing through a first precoder and a pre-compensation stage, wherein the pre-compensation stage is selected to have the transmission symbols receivable at the at least one user device to appear as if the transmission symbols are processed by a second precoder different from the first precoder.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
A wireless communication method includes receiving, by a first wireless device during a training phase, reference tones using a first number of resource elements from a transmitter of a second wireless device, wherein the first wireless device comprises multiple receiving antennas, estimating, by the first wireless device, from the receiving the reference tones, a second order statistics of wireless channels between the multiple receiving antennas and the transmitter of the second wireless device, and performing channel estimation, during an operational phase subsequent to the training phase, using the second order statistics and reference tones received on a second number of resource elements, wherein the second number is less than the first number.
42 - Scientific, technological and industrial services, research and design
Goods & Services
Wireless broadband communication services; wireless signal
processing services. Computer services, namely, design and development of
computer software in the field of wireless communications
for increasing bandwidth of wireless connectivity across
computer networks; design and development of software and
hardware for digital signal processing; non-downloadable
software for increasing bandwidth of wireless connectivity
across computer networks in the field of wireless
communications; software design and development (term
considered too vague by the International Bureau - Rule 13
(2) (b) of the Regulations).
Methods, systems and devices for fractional cooperative multipoint network operation are described. One example method for wireless communication includes determining, by a network device, a cooperative multipoint (COMP) management status of wireless devices served by the network device, and providing, by the network device, wireless connectivity to the one or more wireless devices, wherein the network device jointly manages transmission resources for a first wireless device due to the COMP management status being a joint COMP status and the network device locally manages transmission resources for a second wireless device due to the COMP management status being a local COMP status.
Methods, systems and devices for spatial multiplexing of different radio technologies are described. An example method for wireless communication includes configuring a base station of a fifth generation new radio (5G NR) radio technology cell to perform transmissions in a network according to a set of compatibility rules that allow a backward compatible operation of the base station with a 4th generation Long Term Evolution (4G LTE) radio technology, and performing transmissions or receptions in the 5G NR cell according to the configuring such that the backward compatible operation is achieved based on orthogonality in a spatial domain between transmissions or receptions in the 5G NR cell and the 4G LTE radio technology.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Methods, systems and devices for massive cooperative multipoint network operation are described. One example method for wireless communication includes transmitting, by a network node serving a plurality of mobile devices in a surrounding area, channel condition information and scheduling information for one or more of the plurality of mobile devices to a network-side server, receiving, by the network node from the network-side server, control information for scheduling transmissions to or from each of the one or more of the plurality of mobile devices, and controlling, by the network node and based on the control information, a communication to or from the one or more of the plurality of mobile devices at a future time or a different frequency band or a different spatial direction.
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
Methods, systems and device for achieving synchronization in an orthogonal time frequency space (OTFS) signal receiver are described. An exemplary signal reception technique includes receiving an OTFS modulated wireless signal comprising pilot signal transmissions interspersed with data transmissions, calculating autocorrelation of the wireless signal using the wireless signal and a delayed version of the wireless signal that is delayed by a pre-determined delay, thereby generating an autocorrelation output, processing the autocorrelation filter through a moving average filter to produce a fine timing signal. Another exemplary signal reception technique includes receiving an OTFS modulated wireless signal comprising pilot signal transmissions interspersed with data transmissions, performing an initial automatic gain correction of the received OTFS wireless signal by peak detection and using clipping information, performing coarse automatic gain correction on results of a received and initial automatic gain control (AGC)-corrected signal.
Methods, devices and systems for communication techniques that use the quasi-static properties of wireless channels are described. One example method to improve communication performance includes receiving a set of pilots over a transmission channel between the wireless communication apparatus and a far-end communication apparatus, the transmission channel comprising a first portion that is time-invariant and a second portion that is time-variant, processing the received set of pilots to generate an estimate of the first portion, processing the received set of pilots to generate an estimate of the second portion, and performing a communication based on a channel state information that is a weighted combination of a first term based on the estimate of the first portion and a second term based on the estimate of the second portion.
H04W 72/566 - Allocation or scheduling criteria for wireless resources based on priority criteria of the information or information source or recipient
60.
SCHEDULING AND RETRANSMISSION IN CENTRAL UNITS AND DISTRIBUTED UNITS
Methods, systems and devices for wireless communication are described. One example method includes determining, using resources in a wireless network, a schedule of transmissions between the wireless network and one or more user devices, and controlling the transmissions according to the schedule. The resources are distributed between a central unit (CU) and a distributed unit (DU) according to a resource partitioning scheme. The DU is configured to handle a first set of protocol layers of a communication protocol stack implemented in the wireless network according to a layer partitioning scheme and the CU is configured to handle a second set of protocol layers of the communication protocol stack according to the layer partitioning scheme. The first set of protocol layers excludes an upper medium access control (MAC) layer. The second set of protocol layers excludes a physical layer.
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
H04L 1/16 - Arrangements for detecting or preventing errors in the information received by using return channel in which the return channel carries supervisory signals, e.g. repetition request signals
Methods, systems and devices for distributed cooperative operation of wireless cells based on sparse channel representations are described. One example method includes providing, using a server, seamless wireless connectivity in an area in which a plurality of network nodes are organized as clusters, where each network node is configured to provide wireless connectivity via N angular sectors covering a surrounding area, where N is an integer and wherein angular sectors of the plurality of network nodes collectively cover the area; controlling, by the server, network nodes in a cluster to collect channel condition information for the N angular sectors and communicate the channel condition information to the network-side server, and operating the server to use the channel condition information collected from the network nodes in the cluster to control communication for the network nodes in the cluster at a different time or a different frequency or a different spatial direction.
Device, methods and systems for implementing aspects of orthogonal time frequency space (OTFS) modulation in wireless systems are described. In an aspect, the device may include a surface of an object for receiving an electromagnetic signal. The surface may be structured to perform a non-electrical function for the object. The surface may generate an electrical signal from an electromagnetic signal. The electromagnetic signal may be received from a transmitter. The transmitter may map digital data to a digital amplitude modulation constellation in a time-frequency space. The digital amplitude modulation constellation may be mapped to a delay-Doppler domain and the transmitter may transmit to the surface according to an orthogonal time frequency space modulation signal scheme. The apparatus may further include a demodulator to demodulate the electrical signal to determine digital data.
Methods, systems and devices for forward error correction in orthogonal time frequency space (OTFS) communication systems using non-binary low-density parity-check (NB-LDPC) codes are described. One exemplary method for forward error correction includes receiving data, encoding the data via a non-binary low density parity check (NB-LDPC) code, wherein the NB-LDPC code is characterized by a matrix with binary and non-binary entries, modulating the encoded data to generate a signal, and transmitting the signal. Another exemplary method for forward error correction includes receiving a signal, demodulating the received signal to produce data, decoding the data via a NB-LDPC code, wherein the NB-LDPC code is characterized by a matrix with binary and non-binary entries, and providing the decoded data to a data sink.
H03M 13/11 - Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words using block codes, i.e. a predetermined number of check bits joined to a predetermined number of information bits using multiple parity bits
H03M 13/25 - Error detection or forward error correction by signal space coding, i.e. adding redundancy in the signal constellation, e.g. Trellis Coded Modulation [TCM]
H03M 13/00 - Coding, decoding or code conversion, for error detection or error correctionCoding theory basic assumptionsCoding boundsError probability evaluation methodsChannel modelsSimulation or testing of codes
H03M 13/29 - Coding, decoding or code conversion, for error detection or error correctionCoding theory basic assumptionsCoding boundsError probability evaluation methodsChannel modelsSimulation or testing of codes combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
H03M 13/39 - Sequence estimation, i.e using statistical methods for the reconstruction of the original codes
64.
Orthogonal time frequency space modulation techniques
Orthogonal Time Frequency Space (OTFS) is a novel modulation scheme with significant benefits for 5G systems. The fundamental theory behind OTFS is presented in this paper as well as its benefits. We start with a mathematical description of the doubly fading delay-Doppler channel and develop a modulation that is tailored to this channel. We model the time varying delay-Doppler channel in the time-frequency domain and derive a new domain (the OTFS domain) where we show that the channel is transformed to a time invariant one and all symbols see the same SNR. We explore aspects of the modulation like delay and Doppler resolution, and address design and implementation issues like multiplexing multiple users and evaluating complexity. Finally we present some performance results where we demonstrate the superiority of OTFS.
Methods, systems and devices for wireless communication, which include localization and auto-calibration, are described. One example method includes receiving, at a wireless device, signal transmissions from one or more network devices, and generating, by processing the signal transmissions, a feedback signal for antenna calibration of the one or more network devices. In some embodiments, the antenna calibration is used for performing device localization and feature map generation that is subsequently used for scheduling transmissions in a wireless network.
A fixed wireless access system is implemented using orthogonal time frequency space multiplexing (OTFS). Data transmissions to/from different devices share transmission resources using—delay Doppler multiplexing, time-frequency multiplexing, multiplexing at stream and/or layer level, and angular multiplexing. Time-frequency multiplexing is achieved by dividing the time-frequency plan into subgrids, with the subsampled time frequency grid being used to carry the OTFS data. Antenna implementations include a hemispherical antenna with multiple antenna elements arranged in an array to achieve multiplexing.
H04L 5/00 - Arrangements affording multiple use of the transmission path
H01Q 21/24 - Combinations of antenna units polarised in different directions for transmitting or receiving circularly and elliptically polarised waves or waves linearly polarised in any direction
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
Methods, systems and devices for lattice reduction in decision feedback equalizers for orthogonal time frequency space (OTFS) modulation are described. An exemplary wireless communication method, implementable by a wireless communication receiver apparatus, includes receiving a signal comprising information bits modulated using OTFS modulation scheme. Each delay-Doppler bin in the signal is modulated using a quadrature amplitude modulation (QAM) mapping. The method also includes estimating the information bits based on an inverse of a single error covariance matrix of the signal, with the single error covariance matrix being representative of an estimation error for all delay-Doppler bins in the signal.
H04W 4/80 - Services using short range communication, e.g. near-field communication [NFC], radio-frequency identification [RFID] or low energy communication
H04L 25/03 - Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
H04L 1/06 - Arrangements for detecting or preventing errors in the information received by diversity reception using space diversity
H04L 5/00 - Arrangements affording multiple use of the transmission path
An antenna system that includes a lens portion having a radiation-side curved surface and a feed-side reception surface, the lens portion structured to focus radio frequency radiations entering from the radiation-side curved surface on a focal point located at the feed reception surface and one or more antenna elements at or near the focal point, the one or more antenna elements being separated from each other by a fractional multiple of a center wavelength of a frequency band of operation, and each antenna element communicatively coupled to one or more radio frequency transmit and/or receive chain and being able to transmit and/or receive data from the radio frequency transmit chain according to a transmission scheme.
H01Q 19/06 - Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using refracting or diffracting devices, e.g. lens
H01Q 21/08 - Arrays of individually energised antenna units similarly polarised and spaced apart the units being spaced along, or adjacent to, a rectilinear path
Methods, systems, and devices for spectral sharing wireless systems, wherein multiple user devices share time and frequency resources for uplink and/or downlink transmissions, are described. One example wireless communication system includes a network station, and multiple user devices, wherein data transmissions over the same time and frequency resources are shared between multiple user devices, in downlink and/or uplink, using spatial user device separation that is dynamically computed by the network station, and where the network station derives spatial user device separation based on uplink channel measurements.
A method for signal transmission using precoded symbol information involves estimating a two-dimensional model of a communication channel in a delay-Doppler domain. A perturbation vector is determined in a delay-time domain wherein the delay-time domain is related to the delay-Doppler domain by an FFT operation. User symbols are modified based upon the perturbation vector so as to produce perturbed user symbols. A set of Tomlinson-Harashima precoders corresponding to a set of fixed times in the delay-time domain may then be determined using a delay-time model of the communication channel. Precoded user symbols are generated by applying the Tomlinson-Harashima precoders to the perturbed user symbols. A modulated signal is then generated based upon the precoded user symbols and provided for transmission over the communication channel.
H04L 25/497 - Transmitting circuitsReceiving circuits using code conversion at the transmitterTransmitting circuitsReceiving circuits using predistortionTransmitting circuitsReceiving circuits using insertion of idle bits for obtaining a desired frequency spectrumTransmitting circuitsReceiving circuits using three or more amplitude levels by correlative coding, e.g. partial response coding or echo modulation coding
An Orthogonal Time Frequency Space Modulation (OTFS) modulation scheme achieving multiple access by multiplexing multiple signals at the transmitter-side performs allocation of transmission resources to a first signal and a second signal, combining and converting to a transmission format via OTFS modulation and transmitting the signal over a communication channel. At the receiver, multiplexed signals are recovered using orthogonality property of the basis functions used for the multiplexing at the transmitter.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
H04L 25/03 - Shaping networks in transmitter or receiver, e.g. adaptive shaping networks
72.
Modulation and equalization in an orthonormal time-frequency shifting communications system
A method for modulating data for transmission within a communication system. The method includes establishing a time-frequency shifting matrix of dimension N×N, wherein N is greater than one. The method further includes combining the time-frequency shifting matrix with a data frame to provide an intermediate data frame. A transformed data matrix is provided by permuting elements of the intermediate data frame. A modulated signal is generated in accordance with elements of the transformed data matrix.
A system and method for orthogonal time frequency space communication and waveform generation. The method includes receiving a plurality of information symbols and encoding an N×M array containing the plurality of information symbols into a two-dimensional array of modulation symbols by spreading each of the plurality of information symbols with respect to both time and frequency. The two-dimensional array of modulation symbols is then transmitted using M mutually orthogonal waveforms included within M frequency sub-bands.
A wireless communication method for transmitting wireless signals from a transmitter includes dividing bits of the transport block into a number of code blocks, wherein each code block corresponds to a bit-level of a multi-level modulation scheme used for transmission, and wherein a size of each code block is inversely proportional to a corresponding coding rate used for coding the code block.
H03M 13/00 - Coding, decoding or code conversion, for error detection or error correctionCoding theory basic assumptionsCoding boundsError probability evaluation methodsChannel modelsSimulation or testing of codes
H03M 13/25 - Error detection or forward error correction by signal space coding, i.e. adding redundancy in the signal constellation, e.g. Trellis Coded Modulation [TCM]
H03M 13/27 - Coding, decoding or code conversion, for error detection or error correctionCoding theory basic assumptionsCoding boundsError probability evaluation methodsChannel modelsSimulation or testing of codes using interleaving techniques
H03M 13/29 - Coding, decoding or code conversion, for error detection or error correctionCoding theory basic assumptionsCoding boundsError probability evaluation methodsChannel modelsSimulation or testing of codes combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
42 - Scientific, technological and industrial services, research and design
Goods & Services
Wireless broadband communication services; telecommunications services, namely, transmission and processing of data signals by means of wireless networks Computer services, namely, design and development of computer software in the field of wireless communications for increasing bandwidth of wireless connectivity across computer networks; design and development of software and hardware for digital signal processing; providing online non-downloadable software for increasing bandwidth of wireless connectivity across computer networks in the field of wireless communications; software design and development
76.
CHANNEL QUALITY PREDICTION IN CLOUD BASED RADIO ACCESS NETWORKS
Methods, apparatus and systems for wireless communication are described. One example method includes estimating, based on channel quality information for a first communication channel during a first time interval, a predicted quality of a second communication channel during a second time interval that is a latency interval after the first time interval and using the predicted quality for processing transmissions on the second communication channel during the second time interval.
Co-existence between an Orthogonal Time Frequency Space (OTFS) modulation system and a Long Term Evolution (LTE) system is achieved by generating a number of transmission beams for a first group of user equipment operating using LTE, and a second group of user equipment operating using the OTFS protocol, and transmitting a first group of data packets formatted according to the LTE protocol to the first group of user equipment and a second group of data packets formatted according to the OTFS protocol to the second group of user equipment. The transmissions are performed by precoding and modulating the first group of data packets according to an LTE modulation scheme, and precoding and modulating the second group of data packets according to an OTFS modulation scheme.
H04B 7/0456 - Selection of precoding matrices or codebooks, e.g. using matrices for antenna weighting
H04W 4/06 - Selective distribution of broadcast services, e.g. multimedia broadcast multicast service [MBMS]Services to user groupsOne-way selective calling services
Device, methods and systems for precoding in wireless systems using orthogonal time frequency space multiplexing are described. An exemplary method for transmitting wireless signals includes mapping data to generate a quadrature amplitude modulation (QAM) signal in a delay Doppler domain, determining a perturbation signal to minimize expected interference and noise, perturbing the QAM signal with the perturbation signal, thereby producing a perturbed signal, generating a pre-coded signal by pre-coding, using a linear pre-coder, the perturbed signal, and transmitting the pre-coded signal using an orthogonal time frequency space modulation signal scheme.
In a transmitter apparatus, a known reference signal is superimposed on top of a data signal that is typically not known a priori to a receiver and the combined signal is transmitted. At a receiver, an iterative channel estimation and equalization technique is used to recover the reference signal and the unknown data signal. In the initial iteration, the known reference signal is recovered by treating the data signal as noise. Subsequent iterations are used to improve estimation of received reference signal and the unknown data signal.
A wireless communication method includes receiving, by a first wireless device during a training phase, reference tones using a first number of resource elements from a transmitter of a second wireless device, wherein the first wireless device comprises multiple receiving antennas, estimating, by the first wireless device, from the receiving the reference tones, a second order statistics of wireless channels between the multiple receiving antennas and the transmitter of the second wireless device, and performing channel estimation, during an operational phase subsequent to the training phase, using the second order statistics and reference tones received on a second number of resource elements, wherein the second number is less than the first number.
A method for performing downlink transmissions from a transmitting device to multiple user devices using transmission resources from a multi-dimensional grid of resources is described. The method includes logically partitioning the transmission resources into multiple segments, assigning, to a given user device of the multiple user devices, transmission resources of one or more of the multiple segments, and performing, using at least some of the assigned transmission resources for the given user device, a downlink transmission using an orthogonal time frequency space (OTFS) transformation on data or signals to be transmitted to the given user device.
G01S 7/41 - Details of systems according to groups , , of systems according to group using analysis of echo signal for target characterisationTarget signatureTarget cross-section
82.
Aspects of channel estimation for orthogonal time frequency space modulation for wireless communications
Device, methods and systems for aspects of channel estimation for orthogonal time frequency space (OTFS) modulation in wireless systems are described. In an aspect, a method for wireless communication may include receiving, using multiple receive antennas, from a number of user devices, non-orthogonal pilots wherein at least some transmissions of the non-orthogonal pilots from different user devices overlap in at least some time and frequency resources, estimating individual pilots from the number of user devices by computing a pilot separation filter for each antenna, and estimating the wireless channel at time and frequency resources used by the non-orthogonal pilots by filtering the receiving signal at the multiple receiver antennas.
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
A wireless communication device includes a feed port comprising multiple input feeds, a precoding subsystem that is electrically connected to the feed port; and an antenna subsystem electrically connected to the precoding subsystem. The antenna subsystem is configured to transmit an output signal of the precoding subsystem to multiple wireless stations using multiple beams. The precoding subsystem is configured to perform a precoding operation on an input signal from the feed port, wherein the precoding operation maximizes a desired signal level to interference ratio of transmissions to the multiple wireless stations.
H04B 7/0404 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas the mobile station comprising multiple antennas, e.g. to provide uplink diversity
H04B 7/0408 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas using two or more beams, i.e. beam diversity
H04L 5/00 - Arrangements affording multiple use of the transmission path
84.
Ray tracing technique for wireless channel measurements
The computer-implemented method includes simulating, by a processor, using an electromagnetic solver including ray launching or ray tracing, multiple rays that reach a vicinity of a receiver of a wireless channel, determining locations of interactions of the rays with an environment of the wireless channel, post-processing, using one or more of the multiple rays, information about received signal at the receiver to obtain temporal variations therein, and determining a characteristic of the wireless channel using results of the post-processing.
Described are devices, systems and methods for scheduling multi-user (MU) multiple input multiple output (MIMO) transmissions in a fixed wireless access (FWA) system. One method for scheduling a large number of user devices in a wireless communication system includes a preselection process to pare down the number of user devices to be simultaneously scheduled, and then scheduling that subset of users. In an example, and assuming each user device communicates over a corresponding wireless channel, the preselection process includes determining a number of sets based on a first characteristic of the wireless channels, where each set includes at least one user device, and then determining a subset of user devices by selecting at most one user device from each of the sets. The scheduling of the selected subset of users is based on a scheduling algorithm and a second characteristic of the wireless channels.
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
H04L 5/00 - Arrangements affording multiple use of the transmission path
Methods, systems, and devices for spectral sharing wireless systems, wherein multiple user devices share time and frequency resources for uplink and/or downlink transmissions, are described. One example method includes transmitting transmission symbols from the network station to at least one user device by processing through a first precoder and a pre-compensation stage, wherein the pre-compensation stage is selected to have the transmission symbols receivable at the at least one user device to appear as if the transmission symbols are processed by a second precoder different from the first precoder.
H04B 7/02 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
87.
Channel acquisition using orthogonal time frequency space modulated pilot signals
Techniques for performing channel estimation in an orthogonal time, frequency and space (OTFS) communication system include receiving a wireless signal comprising a data signal portion and a pilot signal portion in which the pilot signal portion includes multiple pilot signals multiplexed together in the OTFS domain, performing two-dimensional channel estimation in a time-frequency domain based on a minimum mean square error (MMSE) optimization criterion, and recovering information bits using a channel estimate obtained from the two-dimensional channel estimation.
An Orthogonal Time Frequency Space Modulation (OTFS) modulation scheme that maps data symbols, along with optional pilot symbols, using a symplectic-like transformation such as a 2D Fourier transform and optional scrambling operation, into a complex wave aggregate and be backward compatible with legacy OFDM systems, is described. This wave aggregate may be processed for transmission by selecting portions of the aggregate according to various time and frequency intervals. The output from this process can be used to modulate transmitted waveforms according to various time intervals over a plurality of narrow-band subcarriers, often by using mutually orthogonal subcarrier “tones” or carrier frequencies. The entire wave aggregate may be transmitted over various time intervals. At the receiver, an inverse of this process can be used to both characterize the data channel and to correct the received signals for channel distortions, thus receiving a clear form of the original data symbols.
Methods, systems and devices for lattice reduction in decision feedback equalizers for orthogonal time frequency space (OTFS) modulation are described. An exemplary wireless communication method, implementable by a wireless communication receiver apparatus, includes receiving a signal comprising information bits modulated using OTFS modulation scheme. Each delay-Doppler bin in the signal is modulated using a quadrature amplitude modulation (QAM) mapping. The method also includes estimating the information bits based on an inverse of a single error covariance matrix of the signal, with the single error covariance matrix being representative of an estimation error for all delay-Doppler bins in the signal.
Device, methods and systems for implementing aspects of orthogonal time frequency space (OTFS) modulation in wireless systems are described. In an aspect, the device may include a surface of an object for receiving an electromagnetic signal. The surface may be structured to perform a non-electrical function for the object. The surface may generate an electrical signal from an electromagnetic signal. The electromagnetic signal may be received from a transmitter. The transmitter may map digital data to a digital amplitude modulation constellation in a time-frequency space. The digital amplitude modulation constellation may be mapped to a delay-Doppler domain and the transmitter may transmit to the surface according to an orthogonal time frequency space modulation signal scheme. The apparatus may further include a demodulator to demodulate the electrical signal to determine digital data.
Methods, systems and devices for reciprocal geometric precoding are described. One example method includes determining, by a network device, an uplink channel state using reference signal transmissions received from multiple user devices, and generating a precoded transmission waveform for transmission to one or more of the multiple user devices by applying a precoding scheme that is based on the uplink channel state, wherein the uplink channel state completely defines the precoding scheme. In some embodiments, the reference signal transmissions and the precoded transmission waveform are multiplexed using either time-domain multiplexing or frequency-domain multiplexing.
Methods, systems and devices for providing transmission resources that achieve transmission diversity while reducing pilot signal overhead are described. An exemplary wireless communication method may be implemented in a wireless communication system in which transmission resources are allocated on a per physical resource block (PRB) basis, where a PRB corresponds to a two dimensional resource pattern comprising a first number of subcarriers along a frequency dimension and a second number time slots along a time dimension. The method includes logically dividing subcarriers in each PRB into an integer number of sub-groups of subcarriers, wherein the integer number is greater than one, allocating, to a transmission, transmission resources corresponding to one or more of the sub-groups of subcarriers, performing the transmission in the wireless communication system.
Methods, systems and devices for fractional cooperative multipoint network operation are described. One example method for wireless communication includes determining, by a network device, a cooperative multipoint (COMP) management status of wireless devices served by the network device, and providing, by the network device, wireless connectivity to the one or more wireless devices, wherein the network device jointly manages transmission resources for a first wireless device due to the COMP management status being a joint COMP status and the network device locally manages transmission resources for a second wireless device due to the COMP management status being a local COMP status.
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
A wireless telecommunications system that mitigates infrasymbol interference due to Doppler-shift and multipath and enables multiple access in one radio channel. Embodiments of the present invention are particularly advantageous for wireless telecommunications systems that operate in high-mobility environments, including high-speed trains and airplanes.
H04B 1/62 - Details of transmission systems, not covered by a single one of groups Details of transmission systems not characterised by the medium used for transmission for providing a predistortion of the signal in the transmitter and corresponding correction in the receiver, e.g. for improving the signal/noise ratio
In a transmitter apparatus, a known reference signal is superimposed on top of a data signal that is typically not known a priori to a receiver and the combined signal is transmitted. At a receiver, an iterative channel estimation and equalization technique is used to recover the reference signal and the unknown data signal. In the initial iteration, the known reference signal is recovered by treating the data signal as noise. Subsequent iterations are used to improve estimation of received reference signal and the unknown data signal.
Wireless communication techniques for transmitting and receiving reference signals is described. The reference signals may include pilot signals that are transmitted using transmission resources that are separate from data transmission resources. Pilot signals are continuously transmitted from a base station to user equipment being served. Pilot signals are generated from delay-Doppler domain signals that are processed to obtain time-frequency signals that occupy a two-dimensional lattice in the time frequency domain that is non-overlapping with a lattice corresponding to data signal transmissions.
Methods, systems and devices for massive cooperative multipoint network operation are described. One example method for wireless communication includes transmitting, by a network node serving a plurality of mobile devices in a surrounding area, channel condition information and scheduling information for one or more of the plurality of mobile devices to a network-side server, receiving, by the network node from the network-side server, control information for scheduling transmissions to or from each of the one or more of the plurality of mobile devices, and controlling, by the network node and based on the control information, a communication to or from the one or more of the plurality of mobile devices at a future time or a different frequency band or a different spatial direction.
H04B 7/024 - Co-operative use of antennas at several sites, e.g. in co-ordinated multipoint or co-operative multiple-input multiple-output [MIMO] systems
H04B 7/0491 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas using two or more sectors, i.e. sector diversity
H04B 7/08 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the receiving station
H04B 7/06 - Diversity systemsMulti-antenna systems, i.e. transmission or reception using multiple antennas using two or more spaced independent antennas at the transmitting station
98.
Digital communication using lattice division multiplexing
A wireless data transmission technique includes encoding information bits as a periodic sequence of quadrature amplitude modulation (QAM) symbols, convolving the periodic sequence with a periodic pulse function, thereby generating a filtered periodic sequence, transforming the filtered periodic sequence to a delay-Doppler domain waveform, converting the delay-Doppler domain waveform to a time domain waveform, and transmitting the time domain waveform.
Methods, systems and devices for forward error correction in orthogonal time frequency space (OTFS) communication systems using non-binary low-density parity-check (NB-LDPC) codes are described. One exemplary method for forward error correction includes receiving data, encoding the data via a non-binary low density parity check (NB-LDPC) code, wherein the NB-LDPC code is characterized by a matrix with binary and non-binary entries, modulating the encoded data to generate a signal, and transmitting the signal. Another exemplary method for forward error correction includes receiving a signal, demodulating the received signal to produce data, decoding the data via a NB-LDPC code, wherein the NB-LDPC code is characterized by a matrix with binary and non-binary entries, and providing the decoded data to a data sink.
H03M 13/11 - Error detection or forward error correction by redundancy in data representation, i.e. code words containing more digits than the source words using block codes, i.e. a predetermined number of check bits joined to a predetermined number of information bits using multiple parity bits
H03M 13/25 - Error detection or forward error correction by signal space coding, i.e. adding redundancy in the signal constellation, e.g. Trellis Coded Modulation [TCM]
H03M 13/29 - Coding, decoding or code conversion, for error detection or error correctionCoding theory basic assumptionsCoding boundsError probability evaluation methodsChannel modelsSimulation or testing of codes combining two or more codes or code structures, e.g. product codes, generalised product codes, concatenated codes, inner and outer codes
H03M 13/39 - Sequence estimation, i.e using statistical methods for the reconstruction of the original codes
H03M 13/00 - Coding, decoding or code conversion, for error detection or error correctionCoding theory basic assumptionsCoding boundsError probability evaluation methodsChannel modelsSimulation or testing of codes
100.
Methods of data communication in multipath channels
Fiber, cable, and wireless data channels are typically impaired by reflectors and other imperfections, producing a channel state with echoes and frequency shifts in data waveforms. Here, methods of using pilot symbol waveform bursts to automatically produce a detailed 2D model of the channel state are presented. This 2D channel state can then be used to optimize data transmission. For wireless data channels, an even more detailed 2D model of channel state can be produced by using polarization and multiple antennas in the process. Once 2D channel states are known, the system turns imperfect data channels from a liability to an advantage by using channel imperfections to boost data transmission rates. The methods can be used to improve legacy data transmission modes in multiple types of media, and are particularly useful for producing new types of robust and high capacity wireless communications using non-legacy data transmission methods as well.
