Patent ID: 6535545
Filing Date: 2003-03-18
Classification: H04B,H04L

Abstract:
A direct sequence spread spectrum radio frequency (RF) modem, comprising:an oscillator having a resonator and adapted to generate an oscillator signal, the center frequency of said oscillator determined by the center frequency of said resonator; switching means for gating said oscillator signal in accordance with input data to be transmitted so as to generate a series of pulses; spreading means for spreading the pulses output of said switching means with a spreading code sequence waveform so as to generate a spread spectrum transmission signal; means for transmitting said spread spectrum transmission signal; means for receiving said spread spectrum transmission signal; correlator means adapted to de-spread said spread spectrum transmission signal in accordance with said code sequence so as to generate a correlator signal; detection means for detecting an envelope of said correlator signal so as to generate a detection signal; and decision means for applying a threshold to said detection signal so as to generate an output data signal therefrom.