Abstract:

In digital wireless communication systems, to reduce the complexity of channel decoding, the soft information always needs to be intercepted as fixpoint information before channel decoding. Upoverflow and downoverflow will be happened during the interception process, and then two kinds of system performance degradation will be occured. Based on joint consideration about these two kinds of overflow, a new adaptive fixpoint information interception method is suggested, so that the system performance will show better than those existed methods and even near to the exhaust algorithm, with high time efficiency. This method is verified by simulations, and then successfully applied to on a broadcast communication platform based on superposition coding.

Key words: wireless communications, soft decoding, fixpoint simulation, overflow, superposition coding