Abstract: Interference cancellation for wideband and narrowband communications systems is provided without apriori knowledge of statistical information about an interfering signal. In one embodiment a demodulator circuit can operate in an environment where a “no lock” situation would normally occur to remove the interference and acquire signals in low signal-to-noise ratio conditions and high signal-to-interference ration conditions. In other embodiments, performance is improved by introducing statistics of the interfering signal, and these statistics regarding the communications channel and interference properties (i.e., characteristics of the interfering signal) can be adaptive or “learned” in other embodiments.

Abstract: Interference cancellation for wideband and narrowband communications systems is provided without apriori knowledge of statistical information about an interfering signal. In one embodiment a demodulator circuit can operate in an environment where a “no lock” situation would normally occur to remove the interference and acquire signals in low signal-to-noise ratio conditions and high signal-to-interference ration conditions. In other embodiments, performance is improved by introducing statistics of the interfering signal, and these statistics regarding the communications channel and interference properties (i.e., characteristics of the interfering signal) can be adaptive or “learned” in other embodiments.

Abstract: Interference cancellation for wideband and narrowband communications systems is provided without apriori knowledge of statistical information about an interfering signal. In one embodiment a demodulator circuit can operate in an environment where a “no lock” situation would normally occur to remove the interference and acquire signals in low signal-to-noise ratio (SNR) conditions and high signal-to-interference ration (SIR) conditions. In other embodiments, performance is improved by introducing statistics of the interfering signal, and these statistics regarding the communications channel and interference properties (i.e., characteristics of the interfering signal) can be adaptive or “learned” in other embodiments.

Abstract: A data encoder for encoding a codeword having a plurality of symbols for transmission through a data channel comprises a turbo encoder which has an interleaver, first and second RSC encoders, a puncturer and a mapper. The interleaver receives the codeword and provides an interleaved codeword. The first RSC encoder is for receiving the codeword and providing first parity bits in accordance with the codeword. The second RSC encoder is for receiving the interleaved codeword from the interleaver and providing second parity bits in accordance with the interleaved codeword. The puncturer is for receiving the codeword, the first parity bits and the second parity bits, and for puncturing at least the first and second parity bits in accordance with a pattern of a desired code rate. The mapper is for receiving the punctured parity bits, and for providing signal sets in accordance with the desired code rate.

Abstract: A decoder structure is described that can be implemented on an integrated circuit and used to decode turbo codes. A soft input soft output decoder includes a metric aggregator, and a codeword resolver, each of these elements co-operating to resolve manipulated branch and state metric pairs to a codeword in a known set of codewords in accordance with an un-normalized likelihood relationship between the received branch and state metric data pairs and the known set of codewords. The present invention is believed to operate at a relatively lower clock speed and occupy a relatively smaller area than previous structures, thereby consuming less power and incurring lower cost to produce, yet still achieve a substantially similar BER performance. The present invention is suitable for extremely high data rate communications; for example, rates in excess of 100 Mbit/s, such as at 200 MHz and 220 MHz, can be achieved.

Abstract: A method of reformatting a data stream comprised of frames arranged into superframes for transmission by a block coding scheme is disclosed herein. The payloads of a plurality of frames are concatenated, where a superframe structure is present the frames in the superframe are concatenated, to form a transmission block. The headers of these frames are replaced by a syncword. The present invention can be used in any communications system which uses MPEG frame form, and can be extended any communications system that can benefit from modification to the frame format.

Abstract: A data encoder for encoding a codeword having a plurality of symbols for transmission through a data channel comprises a turbo encoder which has an interleaver, first and second RSC encoders, a puncturer and a mapper. The interleaver receives the codeword and provides an interleaved codeword. The first RSC encoder is for receiving the codeword and providing first parity bits in accordance with the codeword. The second RSC encoder is for receiving the interleaved codeword from the interleaver and providing second parity bits in accordance with the interleaved codeword. The puncturer is for receiving the codeword, the first parity bits and the second parity bits, and for puncturing at least the first and second parity bits in accordance with a pattern of a desired code rate. The mapper is for receiving the punctured parity bits, and for providing signal sets in accordance with the desired code rate.