# The UWB Radar Application in the Aviation Security Systems
## 1 Introduction
The authors of [23] propose providing UWB with a multi-input multi-output radar system for through-wall imaging using a cross correlation-based time domain back projection algorithm (TDBP). The results of the experiments presented in this work demonstrate that the proposed imaging methods in the range and in azimuth can effectively suppress artifacts and focus on various targets, and the designed MIMO radar system can detect and locate human targets behind the wall [23]. The paper [24] presents a proposal of a MIMO radar system using the compensation method based on the reference channel, and a modified algorithm for displaying reverse Kirchhoff migration is proposed. The modified reverse Kirchhoff migration imaging algorithm has smaller lateral lobes compared to the traditional 3D backward projection algorithm. The proposed MIMO radar system can be used for real-time high-precision 3D through-wall radar imaging of multiple moving targets [24]. We have published some research results in the field of UWB radar signal processing and their application in practice in [25; 26; 27; 28]. The document [26] states that the good penetration ability of UWB signals through most of the materials enables the detection of objects hidden behind walls and other obstacles. In [27], we deal with selected stages of UWB radar signal processing. We present the definition of UWB, as well as some of the phases of the UWB radar signal processing. Next, the procedures of preliminary data processing and ways of static background subtraction are described. In [28], we present the possibilities of background elimination. The purpose of eliminating the background is to increase the signal-to-noise ratio at the received data following preliminary processing. Procedures of the background subtraction can help remove the stationary clutter such as the antenna feed-back and clutters caused by impedance inadaptability. In [29], we present the selected stages of radar signal processing, the information that can be obtained from them, and the errors in determining the target position. The main contribution of this paper consists of the development of algorithms for target location by way of finding the intersections of the ellipses in case of using two independent radar systems. The analysis of the current state of UWB technology in the field of tracking people behind the wall shows that this technology can be used at civil and military airports in the field of security. The published results in this area show that the created algorithms for processing the measurement signals of UWB radars enable sufficiently accurate tracking of people behind obstacles but require great demands on their practical implementation. Therefore, we were looking for new methods of processing UWB radar measurement signals, which would allow tracking the movement of a person behind an obstacle. Our priority was not the accuracy of determining a person's location, but the ability to discover a person and track their movement behind the obstacle. This is one of the possible scenarios for security forces to intervene at the airport to search for or detain dangerous persons.