Cancellation of a sweeping CW interferer in direct sequence spread spectrum signals

A system capable of canceling continuous wave (CW) interference in direct-sequence spread-spectrum signals has been constructed. The system is based on a stepped sweeping phase-locked loop (PLL). The system can function equally well when the interference drifts or sweeps at a rate less than the sweep rate of the PLL used. Practical results indicate that the system gives 23 dB improvement in the signal-to-interferer power ratio at the input of the spread-spectrum processor when the input signal-to-interferer power ratio is -12 dB.<>