Review of the homodyne technique for coherent radar

The merits of using homodyne techniques for coherent radar are examined. The influence of various component deficiencies is discussed with relation to the choice between homodyne and heterodyne. The use of digital IQ signal generation and processing to correct for some of the problems of modulator and demodulator design by predistortion, offset correction, etc. is briefly addressed. A 5.3 GHz synthetic aperture radar designed for strip mapping at high resolution is then considered to illustrate the use of the homodyne approach. Measurement results on quadrature modulators and demodulators at 300 MHz and 5.3 GHz are given to support the contention that the homodyne technique can be applied successfully