Random sequence encoded waveforms for covert asynchronous communications and radar

This work presents a random sequence coding scheme for joint radar-communication waveforms in scenarios that require a high degree of data covertness. The authors' goal is to embed the resultant signals in a parameter space of the probability density function of statistical distribution, leading to the samples of the underlying random process being used for waveform construction. The simulated performance shows that an unfriendly interceptor will be penalised significantly compared to an authorised receiver when the SNR is greater than -20 dB. The proposed method is well-suited for asynchronous, ad-hoc communications with a high low probability of intercept/low probability of detection potential. The authors also propose an algorithm to improve the performance of thus created communication signals when they are used simultaneously for radar. Experimental results for both communications and radar are also presented.