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A spread spectrum multiple access (SSMA) communication scheme employing asynchronous code‐multiplexing technique has been used in both mobile and satellite communication systems. One shortcoming of the SSMA system is the co‐channel interference due to the correlations among the pseudo noise (PN) sequences being used by multiple channels. Such co‐channel interference in the reception limits the number of channels that can share one common frequency band. Furthermore, there is a distant‐dependent problem of different received‐powers from different transmitters. This paper describes a technique for cancelling the co‐channel interference in asynchronous SSMA systems. This technique does not treat the co‐channel interference as thermal noise. It considers the co‐channel interference as components that can be recreated at each receiver. If the correlations among the PN sequences of all the active channels become known, the co‐channel interference can be cancelled using the linear algebraic approach. As a result, a larger number of channels can share the same frequency band more efficiently. Further, if initial synchronization can be implemented then the distant‐dependent problem can be alleviated.

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