Covert Communication in TDCS with Spectrum Measurement Mismatch and Noise Uncertainty

In this paper, the covert performance in transform domain communication system (TDCS) is investigated when there is spectrum measurement mismatch between the warden and the legitimate users under noise uncertainty. Partial/total subcarrier selection scheme of legitimate users will become unpredictable for warden caused by the spectrum measurement mismatch. We derive the average covert probability (ACP) of TDCS in unpredictable subcarrier set. Furthermore, for a given ACP constraint, the maximum achievable covert throughput (ACT) is derived when the total subcarrier selection scheme is unpredictable for warden. Numerical results demonstrate the covert performance of TDCS under the considered scenario.