Radar Imaging Based on IEEE 802.11ad Waveform in V2I Communications

TL;DR

This paper introduces a radar imaging method using IEEE 802.11ad waveforms for vehicular settings, enabling high-resolution vehicle images through joint communication and radar functions.

Contribution

It proposes a novel ISAR imaging technique leveraging IEEE 802.11ad waveforms for joint vehicular communication and radar imaging, with accurate delay and Doppler estimation.

Findings

High-resolution ISAR images are achievable in simulated vehicular scenarios.

The method accurately estimates vehicle velocity using Doppler shifts.

Simulation results confirm the effectiveness of the proposed radar imaging approach.

Abstract

Since most of vehicular radar systems are already exploiting millimeter-wave (mmWave) spectra, it would become much more feasible to implement a joint radar and communication system by extending communication frequencies into the mmWave band. In this paper, an IEEE 802.11ad waveform-based radar imaging technique is proposed for vehicular settings. A roadside unit (RSU) transmits the IEEE 802.11ad waveform to a vehicle for communications while the RSU also listens to the echoes of transmitted waveform to perform inverse synthetic aperture radar (ISAR) imaging. To obtain high-resolution images of the vehicle, the RSU needs to accurately estimate round-trip delays, Doppler shifts, and velocity of vehicle. The proposed ISAR imaging first estimates the round-trip delays using a good correlation property of Golay complementary sequences in the IEEE 802.11ad preamble. The Doppler shifts are then obtained using least square estimation from the echo signals and refined to compensate phase wrapping caused by phase rotation. The velocity of vehicle is determined using an equation of motion and the estimated Doppler shifts. Simulation results verify that the proposed technique is able to form high-resolution ISAR images from point scatterer models of realistic vehicular settings with different viewpoints. The proposed ISAR imaging technique can be used for various vehicular applications, e.g., traffic condition analyses or advanced collision warning systems.