Lukasz Maslikowski

A concept of GSM-based passive radar for vehicle traffic monitoring

In this paper the passive radar used as a transmitter of opportunity GSM BTS stations has been proposed for vehicle traffic monitoring. The paper presents a feasibility study on using GSM signals for traffic control in different environments including urban areas, highways and small agglomeration roads. The initial analysis shows that such system can be successfully used to extract traffic parameters such as the average speed of vehicles and road capacity. Additionally, the presented GSM passive radar concept for vehicle traffic monitoring has been successfully verified using real-life signals recorded during a measurement campaign carried out at the Warsaw University of Technology.

Velocity measurement and traffic monitoring using a GSM passive radar demonstrator

The paper presented an idea for a new potential civilian application for passive radar utilizing a GSM transmitter as the illuminator of opportunity. The concept presented has been verified via the processing of the data recorded during a measurement campaign carried out in a real operational scenario. The results presented in the paper show that a GSM-based PCL system can be used successfully in the future as a new system dedicated to speed control and traffic monitoring, both in urban areas and on small roads and highways. The results presented in the paper show that the system is able to simultaneously distinguish different-sized objects, characterized by different RCSs, as in the example of the truck and cyclist. This result shows the high potential of the proposed system.

Experimental results of the PaRaDe passive radar field trials

In this paper the results obtained during the trials of the PaRaDe (Passive Radar Demonstrator) are presented. The PaRaDe is a passive radar based on FM radio transmitters developed at Warsaw University of Technology. The targets observed during the trials involved highly maneuvering military targets and commercial airliners. The detection results were compared with data acquired with a Mode-S/ADS-B receiver and an active radar.

Passive bistatic SAR imaging — Challenges and limitations

In this article, a concept of passive bistatic SAR (PB-SAR) imaging using a spaceborne SAR radar transmitter of opportunity is presented. This was proposed for the first time in the beginning of this century by Krieger et al and Griffiths et al. Because passive imaging is completely covert and relatively cheap, as it does not require its own transmitter, and the rapid growth of the computational power of processors has made it possible, the topic has attracted the attention of many research institutes. Recently, several bistatic radar experiments have been carried out using ground stationary receivers and spaceborne illuminators, and the results have shown new capabilities of SAR imaging. In most of these trials, cooperative illuminators were used and placed on satellite platforms developed by the country conducting the experiment, means that the receiver has exact a priori information about the transmitters parameters (e.g., carrier frequency, signal parameters, chirp duration, pulse repetition frequency [PRF], etc.). To obtain a passive SAR image when the parameters are roughly known, additional techniques for signal analysis and parameter estimation have to be applied, which make the processing more sophisticated. In this article, the challenges and limitations of the PB-SAR imaging are discussed, and the differences in the signal processing chain in mono- and bistatic configurations are indicated. Finally, the recent results of real passive SAR images are presented. The results were obtained by the Warsaw University of Technology (WUT) in 2013, using their passive radar demonstrator mounted on the ground. As the transmitter of opportunity, the TerraSAR-X satellite was used.

Detection of fast maneuvering air targets using GSM based passive radar

This paper presents the results of the detection of fast maneuvering air targets (e.g. air fighters) using GSM based passive radar. The results were obtained during the measurement campaign carried out by the Warsaw University of Technology on the Polish coast of the Baltic Sea. The main goal of the trials was to verify the possibility of the utilization of a GSM passive radar as a short range air surveillance radar. The results show a broad range of the GSM-based passive coherent location technology capabilities in that area.

The use of CLEAN processing for passive SAR image creation

The paper presents the concept of the use of CLEAN processing for strong direct signal removal in passive SAR systems. The CLEAN algorithm proposed has been successfully verified during several measurement campaigns. During the trials the passive SAR receiver was placed at ground level, and different SAR satellites (e.g. EnviSAT, TerraSAR-X) were used as illuminators of opportunity. Almost all SAR radars use the chirp sounding signal, and the presence of a direct signal in the reference channel limits the quality of the image. The removal of the strong direct signal leads to improvement of the image at a short distance from the receiver, which is the case considered in this paper.

Bistatic ground-based passive SAR imaging using TerraSAR-X as an illuminator of opportunity

The paper presents an experiment with bistatic passive SAR imaging in a scenario involving the TerraSAR-X satellite as an illuminator of opportunity and a static, ground-based receiver. The experiment was performed during a measurement campaign carried out by the Warsaw University of Technology in July 2012. In the paper the design of an X-Band receiver system and the bistatic SAR processing used for imaging are described. Also the resultant images produced for different polarizations of transmitted waves are included.

X-band receiver for passive imaging based on TerraSAR-X illuminator

The paper describes an X-band receiver constructed from Commercial Off-The-Shelf (COTS) elements that was used to capture a radar signal transmitted by the TerraSAR-X satellite. The motivation was to use recorded waveforms to perform ground-based imaging of the surrounding area. The paper describes the motivation, receiver setup and the results of the measurement campaign.

Preliminary results of noise radar experiments

The paper describes the first results of noise radar experiments carried out at Warsaw University of Technology. The radar system was built with Commercial Off-The-Shelf (COTS) components: log-periodic antennas, an arbitrary waveform generator and a two-channel spectrum analyzer. The radar operated in the continuous-wave mode, and the aim was to detect moving targets in the received signal. The paper shows the system setup as well as the numerical results obtained from the recorded signals.

Filter-Based Design of Noise Radar Waveform With Reduced Sidelobes

Noise radars possess several advantageous properties, including low probability of detection and identification, especially when working in continuous-wave mode. One of the main drawbacks of such radars is the occurrence of the masking effect, when a weak target echo is masked by the sidelobes of a strong target echo. The sidelobes of the ambiguity function emerge on the level of the time–bandwidth product below the main peak and are spread in the entire range–Doppler plane. While most approaches to mitigate the masking effect focus on the processing of the received signal, it is possible to move the computation burden to the waveform design phase. This paper describes a filter-based method of creating noise-like waveforms that have very low sidelobes in the area of certain range and Doppler shifts. Both theoretical analysis and measurement results are presented and compared with the lattice filter method of masking effect cancellation.