Programmable fiber optic delay line, and radar target simulation system incorporating the same

A radar target speed and distance simulation system for operating on at least a portion of a radar signal and supplying a delayed signal which incorporates the delay of a delay path back to a radar processor as simulated distance radar target return, comprising:

• a) means for converting said portion of the radar signal into a corresponding optical signal,
• b) a programmable fiber optic delay system for delaying said optical signal by a time period corresponding to a simulated target distance, said delay system comprising:
• 1) a plurality of fiber optic delay lines, each delay line having a programmable delay period,
• 2) means for switching among siad delay lines for inclusion in a delay path, and
• 3) a control computer comprising means for programming said delay lines, with respective series of delays corresponding to a simulated speed of target movement and for coordinating said switching means with the programming of said delay lines so that only a delay line with a settled programmed delay is included in said delay path, and said optical signal emerges as a delayed optical signal after passing through said delay path;
• and
• c) means for converting said delayed optical signal into a corresponding electrical signal which comprises said delayed signal.