Recently, a new class of binary codes for overloaded CDMA systems areproposed that not only has the ability of errorless communication but alsosuitable for detecting active users. These codes are called COWDA [1]. In [1],a Maximum Likelihood (ML) decoder is proposed for this class of codes. Althoughthe proposed scheme of coding/decoding show impressive performance, the decodercan be improved. In this paper by assuming more practical conditions for thetraffic in the system, we suggest an algorithm that increases the performanceof the decoder several orders of magnitude (the Bit-Error-Rate (BER) is dividedby a factor of 400 in some Eb/N0's The algorithm supposes the Poisondistribution for the time of activation/deactivation of the users.
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