Two-Dimensional Imaging of a Pedestrian Using Multiple Wideband Doppler Interferometers with Clustering-Based Echo Association

Abstract

This paper presents a method of imaging a twodimensional section of a walking person using multiple Doppler radar systems. Although each simple radar system consists of only two receivers, different radial speeds allow target positions to be separated and located. The signal received using each antenna is processed employing time-frequency analysis, which separates targets in the time-rangevelocity space. This process is followed by a direction-of-arrival estimation employing interferometry. The data obtained using the multiple radar systems are integrated using a clustering algorithm and a target-tracking algorithm. Through realistic simulations, we demonstrate the remarkable performance of the proposed imaging method in generating a clear outline image of a human target in unknown motion.

False Image Suppression in Two-Dimensional Shape Estimates of a Walking Human Using Multiple Ultra-Wideband Doppler Radar Interferometers

“…To overcome this problem, we now propose a false image suppression method that exploits two means of estimating the target velocity. The proposed method rejects false estimated images by detecting inconsistent combinations of the radial velocity and time derivative of the image positions, and estimates a clear image of multiple targets as a result of improved accuracy [8]. In this paper, we first explain the conventional UWB Doppler radar imaging method, and confirm that false images are output when the scattering centers are misclassified.…”

“…The former does not take into account the motion of scattering centers on the target surface, whereas the latter has only a few echoes, which simplifies the simulated signals. This study used the latter model with cylinders because the motion of scattering centers is essential in improving imaging performance as shown in [8]. An important part of our future research will be to analyze the effectiveness of our proposed approach even for a more realistic target model.…”

“…We have already proposed a UWB imaging method using a small number of antennas [8]. This uses multiple interferometers [9] to estimate the scattering centers of targets in multiple directions [10].…”