Theoretical analysis of M-ary/SS communication systems using racing counters and a hadamard matrix

[出版社版](c)1996 IEEE. Personal use of this material is permitted. However, permission to reprint/republish this material for advertising or promotional purposes or for creating new collective works for resale or redistribution to servers or lists, or to reuse any copyrighted component of this work in other works must be obtained from the IEEE.In this paper, performance of M-ary spread spectrum (M-ary/SS) communication systems is discussed. Firstly, the initial acquisition time is evaluated. Secondly, retention time, which is the average number of frames holding correct frame timing, and recovery time, which is the average number of frames required to establish synchronization, are derived. Lastly, bit-error rate (BER) performance is evaluated. M-ary/SS communication systems, which have more than one spreading code, can improve BER performance under conditions in which there is additive white Gaussian noise (AWGN). However, the synchronization of M-ary/SS communication systems is difficult because they have several spreading codes. The frame synchronization method which is used in this paper uses a Hadamard matrix and "racing counters." As a result, the retention time becomes longer than the recovery time when the size of the lower counter differs greatly from that of the upper counter in the racing counters. Then BER gets close to the performance which is achieved under the complete synchronization