Multiple Access for Transmissions Over Independent Fading Channels

Abstract

We propose to employ a multilevel detection (MLDT) technique to allow multiple users which respectively transmit messages over independent fading channels to share the same resource, e.g., the same signature sequence in the CDMA (code division multiple access) system. The users are separated by the different channel gains including amplitudes and phases resultant from the independent fading channels. In a CDMA system with a fixed amount of available signature sequences, the number of users can be doubled or tripled by using MLDT although there is the cost of some BER performance degradation.