Self-Encoded Multiple Access Multiuser Convolutional Codes in Uplink and Downlink Cellular Systems


Self-encoded spread spectrum eliminates the need for traditional pseudo noise (PN) code generators. In a self-encoded multiple access (SEMA) system, the number of users is not limited by the number of available sequences, unlike code division multiple access (CDMA) systems that employ PN codes such as m-, Gold or Kassami sequences. SEMA provides a convenient way of supporting multi-rate, multi-level grades of service in multimedia communications and prioritized heterogeneous networking systems. In this paper, we propose multiuser convolutional channel coding in SEMA that provides fewer cross-correlations among users and thereby reducing multiple access interference (MAI). We analyze SEMA multiuser convolutional coding in additive white Gaussian noise (AWGN) channels as well as fading channels. Our analysis includes downlink synchronous system as well as asynchronous system such as uplink mobile-to-base station communication.

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J. JUNG, W. JANG and L. NGUYEN, "Self-Encoded Multiple Access Multiuser Convolutional Codes in Uplink and Downlink Cellular Systems," International Journal of Communications, Network and System Sciences, Vol. 2 No. 4, 2009, pp. 249-257. doi: 10.4236/ijcns.2009.24027.

Conflicts of Interest

The authors declare no conflicts of interest.


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