Abstract: A method and apparatus for data communication in a variety of communication systems using spread spectrum techniques and multilevel sequences in which distinct multilevel sequences used contain binary subsequences that interfere constructively such that synchronous cross-correlation values add constructively. By adding two subsequences from different sets, it is ensured that neither subsequence belongs to the same set. This, in combination with use of correlators, reduces complexity and facilitates increasing the order of a modulation scheme, thus enhancing the bandwidth efficiency.

Abstract: A method and apparatus for data communication using signature sequences and spread spectrum techniques to reduce the effects of certain transmission impairments in a Wireless local area network (WLAN). The invention uses a number of correlators and M-ary Code Keying with a Supergold signature sequence for simultaneously generating a periodic signal for acquiring symbol synchronization, a difference squarewave signal for acquiring and maintaining chip synchronization and a sum signal for determining received signal strength and setting threshold levels.

Abstract: Spread spectrum communication techniques and applications using signature sequences are described to reduce the effects of certain transmission impairments such as co-channel interference, multiple access interference and intersymbol interference. Signature sequences with structured properties are obtained by generating cosets from a seed set of sequences, constructing a subset of sequences by concatenating the sequences of a coset and constructing a full set of sequences by concatenating the subsets of sequences.