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Present day direct sequence code division multiple access (DS/CDMA) systems treat each user separately as a signal, with all ofthe other users representing interference or noise. Potentially significant capacity improvements can be achieved ifthe negative effect that each user has on the others is cancelled. In other words, joint detection (multiuser detection), rather than separate detection, is beneficial. Optimal multiuser detection is, however, too complex. Thus, suboptimal approaches have been investigated. The basic principles of optimal and suboptimal multiuser detection are well understood now and effort is underway on investigating practical and economic feasibility. • A comprehensive reference set on spreadspectrum until 1985 is [SI85].

It was previously shown (under simplifying assumptions) that this algorithm gives equal power and time to users who only differ in the distance from the BS, their fading characteristics being the same. We give here a more general result for two classes of users with different fading characteristics. All other things being equal, the user class with more fading variability gets more throughput with a lower (but not much lower) fraction of time transmitting. We also demonstrate a separability property -the effects of variablity and distance from the base station are separable.