Method and apparatus for facilitating multi-rate data transmission by selecting a plurality of spreading codes

摘要

A communication system facilitates multi-rate data transmission by using a set (N) (210) of spreading codes from which a subset (n) (214) of the spreading codes is dynamically selected based on a first set of bits from source digital information to be transmitted. The subset (214) of spreading codes are simultaneously transmitted and used for coding a second set of bits from the source digital information. A receiver has correlators (306-309) to correlate each of the set of spreading codes with a received spread spectrum signal (302) to produce correlated signals. A code subset estimation circuit (312) is coupled to each correlator (306-309) and determines the magnitude of each of the correlated signals. The code subset estimation circuit (312) selects a subset of spreading codes from the set of spreading codes based on the magnitude of all correlated signals and determines the polarity of the subset of codes to decode the encoded received data.