摘要 |
The invention involves a parallel spread spectrum ("PSS") technique of spreading orthogonal encoded data. In a preferred embodiment, a method and system for communicating data comprises encoding (720) and spreading (770) a data stream (772) using a scheme employing orthogonal Walsh functions, and thereby segmenting the data stream into multiple bit data packets representing one of a number of true or inverted Walsh codes. The data stream is then differentially encoded for either BPSK or QPSK modulation, and spread using a PN-sequence. The parallel spread data stream is modulated for transmission to a receiver. At the receiver, the data stream is recovered by computing a cross correlation between the digitized data stream and a programmed sequence. One of the benefits of the PSS techniques over conventional communication systems is that additional processing gain plus data forward error correction can be simultaneously achieved. |