On the Uplink Performance of LAS-CDMA

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Description/Abstract

In this paper Large Area Synchronized (LAS)-CDMA is investigated, which exhibits a significantly better performance than the traditional random code based DS-CDMA system. Closed-form formulas are derived for characterizing the BER performance of LAS-CDMA as a function of the number of resolvable paths Lp, the maximum delay difference τmax and the number of users K when communicating over a Nakagami-m fading channel. Moreover, the limited number of available LAS codes having a certain interference free window width suggests that the employment of LAS-CDMA is beneficial in a low-user-load scenario, where a near-single-user performance can be achieved without a multiuser detector. In this paper Large Area Synchronized (LAS)-CDMA is investigated, which exhibits a significantly better performance than the traditional random code based DS-CDMA system. Closed-form formulas are derived for characterizing the BER performance of LASCDMA as a function of the number of resolvable paths Lp, the maximum delay difference τmax and the number of users K when communicating over a Nakagami-m fading channel. Moreover, the limited number of available LAS codes having a certain interference free window width suggests that the employment of LAS-CDMA is beneficial in a low-user-load scenario, where a near-single-user performance can be achieved without a multiuser detector. Index Terms—Code-division multiple-access, interference free window, LA codes, LS codes, LAS codes, Gaussian Approximation.