Resolving doppler-ambiguity in OFDM-based joint radar and communication sensors

Typical Joint Radar and Communications sensors exploiting OFDM waveforms evaluate the Range-Doppler Map by implementing the suboptimal batch algorithm with a length of the batches equal to the useful part of the OFDM symbols. As well known, this approach yields Doppler ambiguity for fast moving targets, whose Doppler frequency exceeds the inverse of the symbol duration. This paper presents a technique to resolve the Doppler ambiguity for fast-moving targets by transmitting OFDM symbols with a variable cyclic prefix and by applying an appropriate processing scheme to evaluate the Range Doppler Map. © 2023 German Institute of Navigation (DGON).