Abstract: Information is detected in a signal received from a transmission over a MIMO channel from a plurality of transmit antennas. The information is encoded as QAM symbols over space and time and/or frequency.

Abstract: To reduce the number of components needed when compared with an exact-calculation analog equaliser, an analog equaliser is characterised by iterative means arranged in operation to generate an estimate of marginal posterior expectations for received bit values.

Abstract: An analogue multiple input, multiple output (MIMO) detector, comprises an analogue calculator circuit operable to obtain the binary elements of a joint posterior distribution of the probabilities for a transmitted symbol, given a received signal. These probabilities are passed as currents to a marginaliser circuit for each channel, which selects the most probable value for the respective channel's bit.

Abstract: A symbol based communications system involves symbol detection at a receiver in the system. The symbol detection involves determining a set of symbols likely to be present on a sequence of received data. A symbol detector provided to fulfil this role includes means for performing a forward backward recursion means on the basis of a reduced set of active states, to determine state probabilities in a hidden Markov model state trellis. The symbol detector further comprises forward message determination means operable to determine a reduced set of forward messages associated with a set of the available states for performance of the reduced state forward recursion, and backward message determination means operable, independently of the forward message determination means, to determine a reduced set of backward messages associated with a backward message determination means for performance of the reduced state backward recursion.

Abstract: Information is decoded from a signal received from a transmission over a MIMO channel from a plurality of transmit antennas, by means of a decoder and a corresponding decoding method. The signal is received on a plurality of receive antennas, and the information is encoded as a string of symbols over space and time and/or frequency. Each transmitted symbol has one of a plurality of values The decoding method comprises the steps of identifying a predetermined number of sets of symbol values, the sets being the most likely combinations of symbol values to be presented at the transmit antennas at a given time instant, and, for each symbol permitted for transmission, determining and outputting the probability of received information corresponding to the transmission of the symbol at a given antenna, on the basis of the other transmit antennas transmitting the symbol values of one of the identified sets.

Abstract: This invention generally relates to methods, apparatus and computer program code for decoding signals, and more particularly to trellis-based decoding using a variant of a BCJR procedure.

Abstract: A signal processing apparatus comprises a plurality of receiving elements, weighting means, and decoding means. Each of the receiving elements has respective weighting means associated therewith at the decoding means, and is arranged to receive a plurality of signals transmitted from a plurality of transmitters. The weighting means are arranged to apply a complex weighting function to each of a number of the signals received by the receiving elements at a given frequency in order to null the number of signals. The decoding means are arranged to determine a symbol or codeword associated with a non-nulled signal and to incorporate the symbol or codeword in the determination of at least one further symbol or codeword.

Abstract: This invention is generally concerned with methods, apparatus and processor control code for decoding a signal received over a MIMO (multiple input-multiple output) channel.