Randomly Selected Spreading Sequences for Coded CDMA
نویسنده
چکیده
| We consider the eeect of using randomly selected sequence multisets for the uplink of a code-division multiple-access channel. In particular, we calculate a tight lower bound on the expected value of the sum capacity, over the ensemble of randomly selected sequence multi-sets. We show that for large systems, the sum rate penalty for using randomly selected multi-sets is at most 1 nat, and vanishes, as the number of users becomes large, compared to the sequence length.
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