Spread-spectrum detection system for a multi-element antenna

摘要

In a spread-spectrum direction-finding system, the outputs of the several antenna elements (10a-d) are progressively translated in frequency by a chirped local oscillator (14) and mixers (12a-d) and applied to a two-dimensional dispersive filter (18), which time compresses the results of single-frequency components in the antenna-element outputs to narrow pulses. Limiters (24a-d) remove any strong narrow-band components that are compressed by the dispersive delay line (18) so that further processing to detect a spread-spectrum signal is not degraded by the presence of narrow-band signals. The use of a common two-dimensional delay line (18) to provide the time compression avoids the need to maintain phase tracking among a plurality of separate parallel one-dimensional dispersive delay lines.