Design of a DSP-based code-phase-shift keying modem for wireless local area network applications

We present the design of a receiver which employs code-phase-shift keying, an M-ary direct-sequence spread-spectrum technique in which each of the M signaling waveforms is obtained by a different code phase shift of a single pseudonoise sequence. The tracking and acquisition schemes are adapted from conventional DS-SS; while the carrier-wave synchronization problem is solved by a novel phase-invariant reception technique. The design is tested by a DSP-based implementation. Measurement results are compared with theoretical predictions