Improved ISDIC-OSC for parallel interference cancellation

A parallel interference cancellation scheme, based on the iterated soft decision interference cancellation with optimized soft cancellation (ISDIC-OSC) procedure is improved dramatically by replacing the a priori probabilities in every stage of the cancellation process by the a posteriori probabilities of the previous stage. The introduction of a forgetting factor results in an additional gain in acceptable load. With this multiuser detector, loads close to unity can be achieved for PN-CDMA without significant loss as compared to the single user performance for a spreading factor of 256. Over a wide range of spreading factors, loads of about twice the acceptable load of the original ISDIC-OSC detector can be achieved with this refined detector.

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