Code-hopping as a new strategy to improve performance of S-CDMA cellular systems

Unal, B
Tanik, Y
An alternative coding strategy to the fixed spreading code assignment of code-division multiple-access (CDMA) systems, called code-hopping is proposed for the uplink path of synchronous CDMA (S-CDMA) systems. In code-hopping S-CDMA, mobile users swap their spreading codes according to a predetermined hopping pattern. In this way, mobile channels which are identified by the spreading codes are exchanged. Performance of code-hopping on the uplink path of S-CDMA systems is evaluated numerically on a typical S-CDMA system in the case of random hopping and compared to that of conventional S-CDMA, In performance evaluation, the criterion is the uplink outage probability which is defined as the probability of the uplink interference power exceeding a predetermined threshold. The numerical results show that application of code-hopping to the uplink communication of S-CDMA systems decreases the outage probability significantly.


Capacity improvement by code-hopping in S-CDMA systems
Unal, B; Tanik, Y (1998-06-11)
Code-hopping, which is an alternative spreading strategy to the static spreading code assignment of CDMA systems, is evaluated as a method to combat multiuser interference in S-CDMA systems. Uplink capacities of conventional and code-hopping S-CDMA are determined and compared by simulations carried out on a typical S-CDMA system for three nondispersive channels : No-fading, Rayleigh fading and Rician fading. The cellular structure is not composed of regular hexagons, but irregularly shaped natural cells whe...
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Citation Formats
B. Unal and Y. Tanik, “Code-hopping as a new strategy to improve performance of S-CDMA cellular systems,” 1996, p. 1316, Accessed: 00, 2020. [Online]. Available: