Spread spectrum radar

Claim 1

A spread spectrum radar apparatus comprising: means for sequentially transmitting a plurality of carrier signals at preselected center frequencies each having a sequential position and each frequency modulated over a time interval chosen for each carrier signal to establish substantially equal bandwidths within each of said time intervals, such that sequence of frequency modulated transmissions with predetermined time bandwidth products is established said carrier signal frequencies and said bandwidth selected such that spectra of adjacent signals in said sequence of signals are substantially non-overlapping; demultiplexing means having input means coupled to receive echo returns of said sequence of frequency modulated signals and having a plurality of output ports in correspondence with said plurality of carrier signals for providing signals representative of echo returns of each of said frequency modulated signals at said output ports corresponding to said carrier signals; means having a plurality of input ports coupled correspondingly to said plurality of output ports of said demultiplexer means for pulse compressing each echo return in accordance with said frequency modulation and for providing time delays between said input ports and output ports corresponding therewith for each echo return in accordance with said sequential position of its carrier signal thereby providing signals at said output ports of said pulse compression means substantially in time coincidence; detector means having a plurality of input ports coupled correspndingly to said plurality of output ports of said pulse compression-time delay means for providing signals representative of detections of signals coupled from said pulse-compression time delay means; and sum means coupled to receive said signals representative of said detections for providing a signal representative of a sum of all time coincident signals received from said detector means.