Challenges and Prospective Solutions for Non-Uniform Radar Waveforms in a Shared Spectrum

The purpose of this paper is to provide an overview of challenges and methods to design and process a non-uniform radar waveform in a shared spectrum with computationally efficient algorithms to mitigate co-channel interference and en-able standard constant false alarm rate detection and tracking approaches. Computationally efficient processing approaches for non-uniform radar waveforms paired with emerging computing architectures are paving the way for real-time implementation. However, these non-uniform processing schemes need to be paired with interference informed radar waveform design to support interference mitigation processing of OFDM signals to achieve acceptable performance in real world environments. Current challenges associated with optimizing a non-linear radar processing chain for a non-uniform waveform discussed in this paper include processing and signal environment informed wave-form design, OFDM interference rejection, convergence speed of reiterative minimum mean square error (RMMSE) based range Doppler map (RDM) formation, and preservation of Gaussian noise statistics for down-stream processing. Potential solutions discussed to these problems include a waveform optimization based on a restricted isometry property (RIP) constraint, re-mod/demod inference rejection, standard RMMSE, and reduced dimension RMMSE RDM processing.