RSLab | Projects | Development of new methods of acquiring, processing, and visualizing radar signals and images

Development of new methods of acquiring, processing, and visualizing radar signals and images in surface-penetrating multistatic radar (RSF Project #15-19-30012)

Head of project Aleksandr Bugaev, rslab@rslab.ru.
Deputy head of project Andrey Zhuravlev, zhuravlev@rslab.ru.

Abstract

     The modern data registration methods for subsurface imaging is that the samples of a reflected signal on a regular grid are obtained by scanning along parallel equidistant lines with a monostatic or bistatic antenna configuration. In the data processing algorithms the probed surface is assumed flat and the specific implementation of the surface relief, if there is any, is neglected. The requirement for signal acquisition on a regular rectangular grid significantly increases complexity and duration of the data acquisition, while the presence of a surface relief essentially affects the possibility of obtaining a radar image of a hidden object, especially when the object of interest is located in a shallow subsurface layer. With this approach to data acquisition, the data processing and visualization are often carried out at a postponed moment of time, when a repeated data acquisition, if needed, invokes additional costs. This approach appears not only inefficient and unproductive, but also inappropriate for solving problems of short-range and subsurface radiolocation, such as localized object detection (the detection of mines in the ground, defects in structures and materials), the inspection of objects with complex surface relief (monuments and cultural heritage buildings, parts made of composite materials, the inspection of people using a hand-held microwave scanner), the sounding of objects with time-varying shape of their surface (inspection of people in motion, bioradiolocation).
     In the proposed project, the development of the new subsurface radar sampling technique using arbitrary sparse signal samples allowing the maximum available number of degrees of freedom for one or more antenna probes is viewed as the problem of primary importance. A modern 3D-videosensor can be used for solving this problem, as it can both track one or several antenna probes, registering their position and orientation with respect to the probed surface, and register the three-dimensional relief and texture irregularities of the probed surface. Thus, a set of the radar signal samples obtained at different points at a range of discrete frequencies and bound to a three-dimensional topographic map of the probed surface, as well as an optical and/or infrared image of the scene, will be used as the input data for the radar signal processing and image reconstruction. An optical or infrared image of the probed surface is obtained due to the peculiarities of the optical 3D-video sensor functioning. To carry out radar signal processing, new methods will be developed that would allow operating with arbitrary sparse samples and considering the relief and the texture of the probed scene. The problems of computational optimization of the radar signal processing algorithms will be addressed, so that the data received from the probes will be processed and displayed to the operator in real time. The results of the sounding obtained in real time in the form of radar images will enable adaptive interactive data acquisition when the samples are collected mainly in identified areas of interest, while the achieved additional degrees of freedom of one or several probes (the height above the surface, orientation, the direction of polarization and the radiation pattern in the case of multistatic antenna configuration) will make possible additional suppression of artifacts caused by the probed surface relief, the presence of inhomogeneities in the medium, which may correlate with the surface irregularities, or by other foreign shielding objects.
     The data binding system on the basis of a 3D-videosensor proposed in the project allows implementing a technique of radar data visualization in real-time using augmented reality. Unlike the modern systems of augmented reality, in which a computer generates an image that uses only spacial reference and mutual spacial relations of the visible objects to the real world (mostly computer games), the developed technique will allow visualizing the radar image of the probed scene at a desired depth, isosurface of a foreign object or defect, etc.
     The methods of acquiring arbitrary radar signal samples, data processing and visualization developed in this project could then be used for solving a wide range of scientific and engineering problems. Thus, instead of radar antennas other detectors or sensors could be applied. Accordingly, the data visualization system based on augmented reality methods will be able to display the data registered by other types of sensors. The 3D-videosensor-based tracking and data binding system can be used in experiments simulating multi-antenna systems with the only use of a pair of separated transmit and receive antennas, which is actual due to the rapid development of MIMO-technology in communication and radar systems. Methods and approaches developed in the course of the project implementation will provide opportunity of archiving the collected measurements more completely enabling their further thorough representation and analysis using traditional computer visualization techniques and their subsequent replenishment by the data obtained with the same or other sensors.
     The scientific achievement of this project is the exploration and establishing, thanks to development of fast 3D-capture technology, new radar system applications and techniques. The relevance of the stated project topic to actual problems derives from the development of multistatic radar systems and the relevant radar signal processing techniques, the development of the processing techniques of the signals obtained on sparse samples, the development of the information systems that permit collecting and visualizing various data concerning the object of interest, the development of computer systems enabling augmented reality that allow generating a synthetic image displaying the information obtained by detectors and field sensors that are not perceived by human senses.
     The obtained results could in future form the basis for the creation of new devices and techniques – an imaging handheld radar for the detection of prohibited metal and dielectric objects under clothing, a microwave system for screening of freely moving people, a method for evaluating the permittivity of a sample with an arbitrary surface boundary, bioradars.

About the project team

The project team has extensive experience in scientific research in the specified area including international collaboration in international projects supported by Russian and foreign funds:

Russian Foundation for Basic Research (RFBR), joint Russian-Turkish project 12-07-91371 Passive and Active Radar Methods for Imaging of Buried and Concealed Objects;
RFBR, Russian-Italian project 09-07-92420 A study of combined acoustic and holographic subsurface radar methods for cultural heritage inspection in Italy and Russia;
The European Union, FP-7, Grant #269157, Active and Passive Microwaves for Security and Subsurface Imaging;
International Sciences and Technology Center, project ISTC #2541, Holographic Subsurface Radar Intended for Soil and Construction Designs Sounding;
NATO Project CBP.NR.NRCLG.982520 Holographic Subsurface Radar Intended for Searching of Mines in the Soil.

     The results of these studies were published in collaboration with foreign colleagues from Italy, the USA, the UK, Japan, and Turkey in more than 50 publications indexed in the Web-of-Science and Scopus databases.
     The team members of the project designed a unique holographic subsurface radar RASCAN, which is currently produced in small batches. They also received the Prize of the Government of the Russian Federation for this invention. At present the 5th modification of this radar is produced. The radar is well known among subsurface radar experts both in Russia and abroad, whereto it is successfully supplied. In 2010, the radar RASCAN, having passed a serious contest, was shown at the annual Royal Society's Summer Science Exhibition as a device that demonstrates the current advances in science and technology. The project team has extensive experience in organizing Russian and international conferences. Acad. A. S. Bugaev is the chairman of an annual international (up to 2008), and the All-Russian Conference Radiolocation and radio communications afterwards, which is held under his supervision from 2007 to the present with the support of RFBR. A. S. Bugaev is one of the organizers of the All-Russian Conference Radio-electronic means of receiving, processing and visualization of information (2013, 2014), and the International Conference Traffic and Granular Flow – 2011.
     Under the guidance of another project member, Dr. S.I. Ivashov, since 2004 Bauman Moscow State Technical University hosts the Annual International Scientific Conference Short and Ultra-Short Range Radar Systems, for which an own web-based information system is used. It has sufficient functionality to maximize automation of organizing processes (user registration, mailing list management, gathering and distribution of materials, security pass management, etc.). S.I. Ivashov was a member of the organizing committee of the XIV International Conference on Ground Penetrating Radar, GPR'2012 in Shanghai, China, June 4-8, 2012, and currently he is a member of the scientific committee of the 8th International Workshop on Advanced Ground Penetrating Radar, IWAGPR'2015 in Florence, Italy, July 7-10, 2015, http://www.iwagpr2015.eu/. The next symposium IWAGPR'2017 is planned to be held in 2017 in Moscow as a part of this project. The project participants regularly present their reports at the mentioned conference, as well as at the International Conference on Ground Penetrating Radar, which are the major conferences on subsurface radiolocation. Other interdisciplinary scientific conferences are also attended.

Project files and publications

A. V. Zhuravlev, V. V. Razevig, M. A. Chizh, On the Use of Augmented Reality Devices for Subsurface Radar Imaging, Proceedings of Progress In Electromagnetics Research Symposium (PIERS 2016), Shanghai, China, 8-11 August, 2016.
(PDF, 1.4 Mb)

The bid from Bauman Moscow State Technical University presented at the bid session to host 9th International Workshop on Advanced Ground Penetrating Radar (IWAGPR) in Moscow in 2017.
(PDF, 8 Mb)
The letter of support obtained from Prof. L. Capineri, The University of Florence, at the time of preparing this project.
(PDF, 82 kb)
The letter of support of our analogous claim from the members of organizing committee to host the 17th International Conference on Ground Penetrating Radar in Moscow in 2018.
(PDF, 136 kb)
Abstracts of 5 papers submitted to GPR'2016
(PDF, 77 kb)
The letter of support from Dr. Lara Pajewski to host a Meeting and a Training School on Ground Penetrating Radar for Young Researchers in Moscow in 2016.
(PDF, 93 kb)
Bechtel, T.; Capineri, L.; Windsor, C.; Inagaki, M.; Ivashov, S., "Comparison of ROC curves for landmine detection by holographic radar with ROC data from other methods," in Advanced Ground Penetrating Radar (IWAGPR), 2015 8th International Workshop on , vol., no., pp.1-4, 7-10 July 2015. doi: 10.1109/IWAGPR.2015.7292645
(PDF, 175 kb)
Vohra, D.; Bechtel, T.; Thomas, R.D.K.; Capineri, L.; Windsor, C.; Inagaki, M.; Ivashov, S.; Van Scyoc, R., "A test of holographic radar for detection of hidden vertebrate tracks and trackways," in Advanced Ground Penetrating Radar (IWAGPR), 2015 8th International Workshop on , vol., no., pp.1-4, 7-10 July 2015. doi: 10.1109/IWAGPR.2015.7292619
(PDF, 372 kb)
Andrey Zhuravlev, Vladimir Razevig, Sergey Ivashov, Alexander Bugaev, and Margarita Chizh, Microwave Imaging of Moving Subjects by Combined Use of Video-tracker and Multi-static Radar. IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems. 2 - 4 November 2015, Tel Aviv, Israel.
(PDF, 1.4 Mb)
Andrey Zhuravlev, Vladimir Razevig, Sergey Ivashov, Alexander Bugaev, and Margarita Chizh, Experimental Simulation of Multi-Static Radar with a Pair of Separated Movable Antennas. IEEE International Conference on Microwaves, Communications, Antennas and Electronic Systems. 2 - 4 November 2015, Tel Aviv, Israel.
(PDF, 1.6 Mb)