Dual-band linear frequency-modulated continuous wave radar receiver with high image rejection based on microwave photonic I/Q mixer

摘要

We propose a dual-band linear frequency-modulated continuous wave (LFMCW) radar receiver based on a microwave photonic in-phase and quadrature (I/Q) mixer, able to simultaneously operate on two different bands over a very board frequency range. The sharing of hardware resources and joint processing of dual bands are implemented by applying a special dual-band sensing waveform. An unambiguous and independent distance measurement of S- and C-bands is demonstrated experimentally. The results exhibit a high and uniform image rejection more than 28 and 30 dB for S- and C-bands, allowing a further improvement of around 15 dB and 10 dB using digital signal processing (DSP).