Incorporating hopped spectral gaps into nonrecurrent nonlinear FMCW radar emissions

The time-varying landscape of spectral congestion is driving the investigation into new forms of “spectrally aware” radar emissions based on passive sensing of the environment. The recent Pseudo-Random Optimized FMCW (PRO-FMCW) framework, which can be viewed as an instantiation of FM noise radar, generates a nonlinear FMCW waveform that does not repeat and is designed using spectrally shaped optimization to improve range sidelobe and spectral containment. Here, these concepts are combined to generate time-varying spectral gaps within the PRO-FMCW waveform to avoid in-band interference. The impact on radar range sidelobe performance is considered with regard to both static and time-varying spectral gaps.