CODE REUSE MULTIPLE ACCESS FOR SATELLITE RETURN LINK

摘要

This invention is a multiple access communication technique by which a multitude of transmitters communicate with receivers using direct sequence spread spectrum signaling. The direct sequence codes are reused by a large number of simultaneous transmitters, so the system is named Code Reuse Multiple Access ("CRMA"). This reuse method requires only a small number of codes relative to the number of simultaneous transmitters, and can use as few as one code for all the users. The direct sequence codes are not required to have special properties such as maximal length. The lengths of the spreading codes employed are not necessarily related to the bit or symbol interval. CRMA can be implemented on a Paired Carrier Multiple Access ("PCMA") system with or without a novel receiver structure which is also described. In an environment having virtual channels, a clock is derived from the received signal in the uplink by sampling the signal to detect symbol edges.