ORTHOGONAL CODE DIVISION MULTIPLE ACCESS COMMUNICATION SYSTEM HAVING MULTICARRIER MODULATION

摘要

An orthogonal code division multiple access (OCDMA) communication systemhaving multicarrier modulation.The incoming input data stream is broken into multiple parallel streamsthrough serial to parallel converters (10, 12),each of which modulates its own frequency-division multiplexed carrier. Thisreduces the chipping rate such that thedelay spread does not cause excessive access noise. Particularly robust delaylock loop (DLL) code tracking andparticularly robust automatic frequency control (AFC) are provided in thepresence of frequency-selective fading.