Advanced Multiple Access for Wireless Communications

Multiple access protocols are used to permit large numbers of independent transmitters to share a common communication channel. CDMA was developed as a multiple access network protocol for military applications during the last forty years. Recently considerable interest in using CDMA in the civilian sector has been evident. The implementation of CDMA multiple access networks is difficult because of the use of a different spreading code for each transmitter in a given network. In addition the use of different codes for each transmitter leads to system complexities which limit the suitability of CDMA networks for certain kinds of data network applications. Recent research has shown that the use of different codes in CDMA systems is not necessary for most applications in the civilian sector, and may not be desirable even in some military applications. In this proposal we describe an applied development program to development program to develop this advanced form of CDMA. Anticipated Benefits: The results of this development program can be used to build simpler, less expensive wireless data networks for mobile/nomadic laptop computers, personal digital assistants and information appliances, in-vehicle navigation and mapping systems, and work-in-progress tracking devices for automated factories.