James Brice Ricketts

US Patent:

44752083, Oct 2, 1984

Filed:

Jan 18, 1982

Appl. No.:

6/340022

Inventors:

James A. Ricketts - Lubbock TX

International Classification:

H04K 102
H04K 110

US Classification:

375 1

Abstract:

A wired spread spectrum data communication system includes a modulator and a demodulator coupled to a transmission line having other signals thereon. The modulator includes a pseudo-noise (PN) generator and a clock providing, respectively, a PN code signal and a clock signal for combination in exclusive-OR (XOR) gates with a low bit rate data signal. The demodulator includes a phase locked loop for clock signal recovery and an identical PN generator providing, respectively, a local clock signal and PN code signal for combination in XOR gates with the encoded data signal for the removal of the clock and PN code signal components from the encoded data signal. The demodulator further includes circuitry for synchronizing the local PN code signal with the PN code component of the incoming encoded data signal.