Fiber-optic radar calibration

A simple fiber-optic radar calibration target is described. Its operation is based on a wideband fiber, a laser transmitter that is directly modulated by the down-converted radar signal and an optical diode receiver recovering said signal. Further up-conversion having a common local oscillator with the first mixer ensures fidelity of the calibration return. Measured useful bandwidth exceeds 200 MHz and practically any radar RF frequency can be handled when suitable mixers are employed. Amplifiers can be added to the down-converted path as desired to compensate for the fiber loss. Modulation and LO sweep provide easy ways of introducing artificial fluctuations and Doppler frequencies. Particularly pulsed radars are readily tested with the proposed scheme as no restrictions are posed by the radar's TR-switch delays.

[1]  Phuong Phu,et al.  A test target generator for wideband pulsed Doppler radars , 1995, Proceedings of 1995 IEEE MTT-S International Microwave Symposium.

[2]  Edward I. Ackerman,et al.  RF fiber-optic link performance , 2001 .

[3]  D. K. Barton,et al.  Radar system analysis and modeling , 2004, IEEE Aerospace and Electronic Systems Magazine.

[4]  G. Barton,et al.  The RADSIM high fidelity radar and EW simulation , 1993 .

[5]  J.N. Briggs Target detection by marine radar , 2005, IEEE Aerospace and Electronic Systems Magazine.

[6]  Leo W. Hollberg,et al.  Using diode lasers for atomic physics , 1991 .

[7]  Randall G. Hulet,et al.  Instrumentation for the stable operation of laser diodes , 1990 .

[8]  John L. Hall,et al.  A low‐noise high‐speed diode laser current controller , 1993 .