Abstract

Digital television (DTV) broadcasting using COFDM modulation is designed to modulate orthogonal frequency-division-multiplexed (OFDM) mid-band carriers with metadata including synchronization signals and transmission-mode signals. DTV signals modulate OFDM carriers occupying portions of the frequency spectrum of the transmission channel that extend in frequency both below and above these mid-band carriers. The OFDM midband carriers are capable of signaling when a new broadcast service is used that differs from the one disclosed. The signaling is provided by modulating the midband carriers with respective elements of signature sequences, each of which signature sequences is composed of Zadoff-Chu sequences and repetitive pseudo-random sequences scrambled by a Zadoff-Chu sequence.

IPC Classes  ?

• H04N 5/40 - Modulation circuits
• H04N 21/2383 - Channel coding of digital bit-stream, e.g. modulation
• H04L 27/26 - Systems using multi-frequency codes

Abstract

A method for managing repository items is provided for a system having a multiple schema repository that uses a database for storing data for the repository items and management data. The database is configured to manage multiple schemas. The management data for the repository includes information for defining and locating the repository items. The multiple schemas include classification schemas for supporting different types of repository items and a management schema for the management data. The method includes receiving a file including a repository item and data associated with the repository item, wherein the associated data includes categorizing information for the repository item. The method also includes determining whether the database already includes the repository item. The method further includes, if the repository item is not already in the database, creating a management record for the repository item, and storing the file in a storage area associated with the database.

IPC Classes  ?

• G06Q 30/00 - Commerce