Multistatic Ultra-wideband Radar Research Articles

Through‐the‐floor localization of a static person by a multistatic UWB radar

AbstractA new approach to through‐the‐floor localization of a static person using an ultra‐wide band (UWB) radar is introduced in this article. The proposed solution is based on a multilateration method appropriately modified for target localization by a multistatic UWB radar employing 1 transmitting (Tx) and 4 receiving antennas (Rxi). Due to an appropriate radar antenna array layout, a geometrical interpretation of the considered problem of localization allows finding the target coordinates by a simple computation of 2 intersections of 2 pairs of ellipses. The mentioned ellipses are defined by the antenna layout and time‐of‐arrivals corresponding to the target that were estimated for the particular pairs of Tx–Rxi antennas. Experimental analysis of the proposed method of through‐the‐floor localization of a person confirmed its good accuracy, despite being such a complex scenario.

Improved Detection of Human Respiration Using Data Fusion Basedon a Multistatic UWB Radar

This paper investigated the feasibility for improved detection of human respiration using data fusion based on a multistatic ultra-wideband (UWB) radar. UWB-radar-based respiration detection is an emerging technology that has great promise in practice. It can be applied to remotely sense the presence of a human target for through-wall surveillance, post-earthquake search and rescue, etc. In these applications, a human target’s position and posture are not known a priori. Uncertainty of the two factors results in a body orientation issue of UWB radar, namely the human target’s thorax is not always facing the radar. Thus, the radial component of the thorax motion due to respiration decreases and the respiratory motion response contained in UWB radar echoes is too weak to be detected. To cope with the issue, this paper used multisensory information provided by the multistatic UWB radar, which took the form of impulse radios and comprised one transmitting and four separated receiving antennas. An adaptive Kalman filtering algorithm was then designed to fuse the UWB echo data from all the receiving channels to detect the respiratory-motion response contained in those data. In the experiment, a volunteer’s respiration was correctly detected when he curled upon a camp bed behind a brick wall. Under the same scenario, the volunteer’s respiration was detected based on the radar’s single transmitting-receiving channels without data fusion using conventional algorithm, such as adaptive line enhancer and single-channel Kalman filtering. Moreover, performance of the data fusion algorithm was experimentally investigated with different channel combinations and antenna deployments. The experimental results show that the body orientation issue for human respiration detection via UWB radar can be dealt well with the multistatic UWB radar and the Kalman-filter-based data fusion, which can be applied to improve performance of UWB radar in real applications.

Multi-Static UWB Radar Approach Based on Aperture Synthesis of Double Scattered Waves for Shadow Region Imaging

SUMMARY The applicability in harsh optical environments, such as dark smog, or strong backlight of ultra-wide band (UWB) pulse radar has a definite advantage over optical ranging techniques. We have already proposed the extended Synthetic Aperture Radar (SAR) algorithm employing double scattered waves, which aimed at enhancing the reconstructible region of the target boundary including shadow region. However, it still suffers from the shadow area for the target that has a sharp inclination or deep concave boundary, because it assumes a mono-static model, whose real aperture size is, in general, small. To resolve this issue, this study proposes an extension algorithm of the double scattered SAR based on a multi-static configuration. While this extension is quite simple, the effectiveness of the proposed method is nontrivial with regard to the expansion of the imaging range. The results from numerical simulations verify that our method significantly enhances the visible range of the target surfaces without ap riori knowledge of the target shapes or any preliminary observation of its surroundings.