Nine new 2-D OOCs are presented here, all sharing the common feature of a code size that is much larger in relation to the number of time slots than those of constructions appearing previously in the literature. Each of these constructions is either optimal or asymptotically optimal with respect to either the original Johnson bound or else a non-binary version of the Johnson bound introduced in this paper.The first 5 codes are constructed using polynomials over finite fields -the first construction is optimal while the remaining 4 are asymptotically optimal. The next two codes are constructed using rational functions in place of polynomials and these are asymptotically optimal. The last two codes, also asymptotically optimal, are constructed by composing two of the above codes with a constant weight binary code.Also presented, is a three-dimensional OOC that exploits the polarization dimension.Finally, phase-encoded optical CDMA is considered and construction of two efficient codes are provided.
Abstract-The high-speed data services, up to about 14.4Mbps, for the 3G networks will be supported by the high-speed downlink packet access (HSDPA) concept. Adaptive modulation and coding (AMC), multicode operation and hybrid automatic repeat request (HARQ) are the enabling technologies used for HSDPA. The next generation mobile communications systems is anticipated to support even higher data rates up to and exceeding 100Mbps. MC-CDMA and DS-CDMA, both using frequency-domain equalization, are considered the most promising wireless access schemes. In this paper, we compare the throughput performance of MC-and DS-CDMA when packet data are transmitted as in HSDPA with AMC and HARQ using multiple codes.
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