Patent ID: 6532253
Filing Date: 2003-03-11
Classification: H04B,H04L

Abstract:
A spread spectrum communication system comprising:a transmitter circuit for generating a signal using trellis-coded modulation, wherein the signal is encoded and modulated based upon a plurality of input source symbols; and a receiver circuit for receiving and decoding the signal to output the plurality of input source symbols wherein the transmitter circuit comprises: a data source for generating the plurality of input source symbols; a convolutional encoder for encoding the input source symbols; a pseudo-noise (PN) generator for generating a PN code sequence; a clock and control circuit for supplying a clock signal to the PN generator; a constellation signal selection logic for outputting an in-phase (I) signal and a quadrature-phase (Q) signal based upon mapping of one of the plurality of input source symbols and one of the trellis encoded input source symbols to a constellation signal, and for spreading the I signal and Q signal based on said PN code sequence; and an up-converter for receiving the I signal and the Q signal from the constellation signal selection logic and outputting a modulated signal in response to the I signal and the Q signal.