Extended Logarithmic Frequency Domain Rulers for Joint RadarCommunications This paper studies the design and performance of a new class of Doppler estimation capable waveforms called Extended Logarithmic Frequency Domain Rulers (ELFDRs) for joint radarcommunications. ELFDRs are multicarrier waveforms whose carriers are spaced according to an Extended Golomb Ruler after a logarithmic warping of the frequency axis. The multiplicative Doppler shift additively translates the waveformxe2x80x99s logarithmically warped spectrum, which allows simultaneous signal detection and Doppler shift estimation via convolutional matched filtering of the logarithmically warped power spectrum. We propose to use these waveforms for communications by phase modulating the carriers and using the estimated Doppler shift to adjust a pilot tone time domain matched filter for fine symbol synchronization. The synchronized waveform is then sent to a communications module for symbol decoding. This paper gives an example of these waveforms, details their design, illustrates a receiver, and explores their bit error rate in AWGN and multipath.

Range and Velocity Estimation for DFRFTOFDMBased Joint Communication and Sensing Systems As being able to share radio frequency (RF) hardwares and spectrum bandwidth, joint communication and radar sensing system has attracted a lot of attention. The integrated waveforms based on orthogonal frequencydivision multiplexing (OFDM) with fast Fourier transform (FFTOFDM) and OFDM with discrete fractional Fourier transform (DFRFTOFDM) have been developed. However, the existing derived ambiguity function does not distinguish the two waveforms clearly. In addition, few range and velocity estimation algorithm for DFRFTOFDMbased integrated waveform has been investigated. Therefore, in this paper we derive the ambiguity function of the DFRFT OFDMbased waveform based on wideband analysis, which shows the superiority of the DFRFTOFDMbased integrated waveform on range resolution. Moreover, range and velocity estimation algorithms based on pulse compression and coherent accumulation are proposed for the DFRFTOFDMbased integrated waveform, respectively. Simulation results validate that the proposed algorithms can accurately estimate the distances and velocities of multiple moving targets.