The Directv Group, Inc.

Hughes Electronics Corporation

Roger Hammons

Mustafa Eroz

Hesham El-Gamal

Bharath Venkataraman

Bharath Venkartaramn

A communication system for transmitting encoded signals over a communication channel is disclosed. The system includes a transmitter, which has a source that is configured to output a plurality of input signals. The transmitter also includes an encoder that is configured to generate a plurality of output signals in response to the plurality of the input signals to output a code word according to the plurality of output signals, wherein the code word has a predetermined algebraic construction for space-frequency coding based upon the communication channel being characterized as a frequency selective block fading channel. Further, the transmitter includes a modulator that is configured to modulate the code word for transmission over the communication channel, and a plurality of transmit antennas that configured to transmit the modulated code word over the communication channel. The system encompasses a receiver that includes a plurality of receive antennas, in which the receiver is configured to receive the transmitted code word via the plurality of receive antennas. The receiver employs an OFDM-front end to transform the Intersymbol Interference (ISI) channel characteristics of the communication channel to selective block fading characteristics.

Space-time trellis code for orthogonal frequency division multiplexing (OFDM)

A system and method for decoding encoded data is provided. A parser receives and parses the encoded data into data streams, with each of the data streams including a portion of said encoded data. A decoder decodes the data streams to provide decoded data which includes soft decision data. The decoder performs an decoding iteration on each of the data streams to provide the decoded data, and performs such decoding iterations based on additional information. The system and method alternatively can be configured without a parser, and can employ at least one soft decoder module and another decoder module. The soft decoder module performs multiple decoding iterations on the encoded data to provide soft decision data and the other decoded module decodes the encoded data based on the soft decision data to provide hard decoded data representative of a decoded condition of said encoded data and/or soft decision data.

System and method employing a modular decoder for decoding turbo and turbo-like codes in a communications network

An approach for performing computations that require processing of values in a forward sweep as well as a reverse sweep, such as the Maximum A Posteriori (MAP) algorithm, is disclosed. A first series of values are computed, in which only every f value of the first series of values and associated normalization values are stored. The first series of values are indexed such that these first series of values are partitioned in time as blocks. The first series of values are recalculated on a per block basis, whereby a second series of values are calculated in response to these recalculated first series of values.

Growing community of inventors

N. Potomac, MD, United States of America

Roger Hammons