Spread Spectrum in a Four-Phase Communication System Employing Adaptive Antennas

This paper discusses the use of spread spectrum in a four-phase communicaton system employing adaptive antennas. A system is described that provides protection against both conventional (i.e., noise and CW) and smart (in particular, repeat) jamming with rapid acquisition of the signal at the receiver. A method is shown for generating reference signals required by the adaptive array through the use of spread spectrum. With these reference signals, the received antenna pattern can be adapted to maximize desired signal to interference and noise power ratio at the receiver. The signal acquisition technique is also described and analyzed. Analytical and experimental results demonstrate both the rapid acquisition and protection against jamming with this system.