Branch-and-bound-based fast optimal algorithm for multiuser detection in synchronous CDMA
نویسندگان
چکیده
A fast optimal algorithm based on the branch and bound (BBD) method is proposed for the joint detection of binary symbols of K users in a synchronous Code-Division Multiple Access (CDMA) channel with Gaussian noise. Relationships between the proposed algorithms (depth-first BBD and fast BBD) and both the decorrelating decision feedback (DF) detector and sphere decoding (SD) algorithm are clearly drawn. It turns out that decorrelating DF detector corresponds to a “one-pass” depth-first BBD; sphere decoding is in fact a type of depth-first BBD, but one that can be improved considerably via tight upper bounds and user ordering as in our fast BBD.
منابع مشابه
Improved Multiuser Detection in Code-division Multiple Access Communications
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