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arXiv · 2302.00700

Multi-Carrier Wideband OCDM-Based THz Automotive Radar

Sangeeta Bhattacharjee·Kumar Vijay Mishra·Ramesh Annavajjala·Chandra R. Murthy
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Abstract

Automotive radars at the Terahertz (THz) frequency band have the potential to be compact and lightweight while providing high (nearly-optical) angular resolution. In this paper, we propose a bistatic THz automotive radar that employs the recently proposed orthogonal chirp division multiplexing (OCDM) multi-carrier waveform. As a stand-alone communications waveform, OCDM has been investigated for robustness against interference in time-frequency selective channels. The THz-band path loss, and, hence, radar signal bandwidth, are range-dependent. We address this unique feature through a multi-carrier wideband OCDM sensing transceiver that exploits the coherence bandwidth of the THz channel. We develop an optimal scheme to combine the returns at different range/bandwidths by assigning weights based on the Cramer-Rao lower bound on the range and velocity estimates. Numerical experiments demonstrate improved target estimates using our proposed combined estimation from multiple varied-attenuation THz frequencies.

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Sangeeta Bhattacharjee, Kumar Vijay Mishra, Ramesh Annavajjala, Chandra R. Murthy. 2023-02-01. Multi-Carrier Wideband OCDM-Based THz Automotive Radar. https://arxiv.org/abs/2302.00700

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