Patent ID: 7653865

Claim:
A method of decodinq a symbol sequence in a received DS-CDMA signal, comprising the steps of: iterative calculation of a hard-decision vector, using a decision threshold having a value based on the probability of each ternary alphabet element of each symbol in the hard-decision vector; demodulating the received signal, thereby providing a symbol sequence; calculating a matrix product of the symbol sequence and a Hadamard decoding matrix; calculating an estimate of a decision threshold, assuming equal probability of the ternary alphabet element of each symbol in the symbol sequence; calculating a hard-decision vector using the calculated decision threshold; calculating an estimate of the probability of each ternary alphabet element of each symbol in the hard-decision vector; calculating a decision threshold using the estimate of the probability of each ternary alphabet element of each symbol in the hard-decision vector; and iterating the steps of calculating a hard-decision vector, calculating an estimate of the probability of each ternary alphabet element of each symbol in the hard-decision vector and calculating a decision threshold using the estimate of the probability of each ternary alphabet element of each symbol in the hard-decision vector, until the calculation of a decision threshold converges or the number of iterations reaches a predetermined maximum number of iterations.