The performance of synchronous direct-sequence spread spectrum signals replicated in several frequency bands

The bit error rate of synchronous direct-sequence spread spectrum signals which are replicated in several frequency bands and coherently added at the receiver is the same in the presence of interferences as the bit error rate for signals spread into a single large band of bandwidth equal to the sum of the bandwidths of the replication bands. Replication may be advantageous if (1) only disjoined bands are available, or if (2) a low spreading chip rate is desirable, then a large band can be divided into several contiguous sub-bands, the signal is replicated in the sub-bands with a lower chip rate than the chip rate which would be required to spread into the large band, yet the bit error rate is not affected.