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In the course of NATO SET-195 RTG work, a field trial with active and passive PCL sensors was conducted. The aim of the trial was to compare experimental results with DMPAR (Deployable Multiband Passive-Active Radar) simulations. Although DMPAR has been devised as collocated receiver system, trials were planned with collocated as well as distributed receiver configurations. Received data has shown that distributed configuration can and will fill in the gaps in the radar coverage created by terrain shadowing or multipath propagation. Also, the overall score in terms of Track Visibility (TV) and Probability of detection (Pd) have been improved in the collocated configuration. Results of the trials have confirmed operational properties of passive-active sensor proposed by SET-195. In this paper a short introduction summing up SET-152 and SET-195 work will be presented. Next, received results of collocated and distributed DMPAR will be shown, analyzed, compared and commented. Now, using those results one can analyze and project on operational characteristics of a distributed DMPAR.

The most comprehensive challenge in tracking system for PCL-PET (Passive Coherent Location – Passive Emitter Tracking) multistatic passive radiolocation system is the problem of ambiguity of measurement association to tracks due to different coordinate systems (bistatic and polar systems for measurements and Cartesian system for tracking). This paper analyzes measurement association methods in order to maximize the sum of gains of all associations and also analyzes multihypothesis measurement association method.

Density based search is the data mining method that can be used in PCL-PET plot level fusion. The following paper is focused on cluster parameter analysis on basis of which proper input parameter allocation to DBSCAN algorithm is discussed. What is more, a set of quality indicators is introduced along with a set of simulation results for observing algorithm performance as a function of input parameters.

The outcome of NATO SET-195 RTG concerning “Short term verification of DMPAR concept” gave promising results in the subject of centralized and decentralized fusion. Basing on this concept and study we further expand it to not only compare results of signal and data fusion, but also propose a processing framework in which both cueing and threshold management can be used. In this paper we present our approach and through simulation we show its performance.

In this paper DMPAR Evaluation Trials for Operationally Upgraded Radar (DETOUR) and their results for a selected scenario are described. The DETOUR trials were conducted by the SET-195 research task group (RTG) under an umbrella of NATO Science and Technology Organization from September 1 to 4, 2014 as a part of the DMPAR (Deployable Multi-band Passive/Active Radar) algorithms' evaluation process. An idea of DMPAR was to combine active and passive surveillance components in a collocated and distributed net of sensors, which would bring multiple benefits. By focusing on one of the trial scenarios, the paper describes all of them, in a form of the measured data analysis. Beside the trials, positive aspects of the combined active and passive surveillance components are discussed.

The paper presents a concept of a versatile signal processor designed for a modern, active electronically scanned array (AESA) radar. The flexibility of the design is high enough to support most advanced modes of operation, including multiple-input multiple-output (MIMO) modes and cognitive radar control, reacting in real time to changing air situations. The required signal processing power calculations are provided together with hardware solutions meeting high computational power and low latency requirements.

This paper demonstrates performance evolution starting with a traditional one band active radar through a two band radar using MIMO (Multiple Input Multiple Output) data and signal fusion ending with a two band radar with some of a cognitive features such as resource management and waveform diversity. A probability of detection of small RCS targets can be improved by utilization of some MIMO processing features: centralized and decentralized fusion. The cognitive features can support the MIMO signal and data fusion to enhance the detection of the contemporary and future air threats.

We discuss the problem of poor initial estimation of altitude of distant and low located objects in PCL-PET data fusion. We focus here on tracking algorithm showing how one can make the convergence of the estimate to the real value faster. The main result is that on having replaced extended Kalman filter with unscented Kalman filter, we are able to choose from scenarios with various initial conditions the one which gives (statistically) the best estimation of position and velocity of an object.

To protect radar against missile attacks a system of additional microwave signal emitters is used. These so-called traps or decoys should emit pulses that might hinder the precise targeting of the protected source by forming a composed microwave radiation signal. The simulation model of the radar system and radar traps is proposed. The designed simulation model allows to estimate the probability of survival of the system for given scenarios of missile attacks leading to the calculation of a certain statistics of protection.

The topic of data fusion on the level of plots in a multistatic, multiband netted radar is widely recognized as a topic of interest in the radar community. PCL-PET system currently under development in PIT-RADWAR S.A. is an example of such approach. Earlier analyses have shown, that unique capabilities provided by the two types of the passive sensors will greatly enchance parameters of the combined sensor. The plot correlation and de-ghosting algorithm has proven to be the most computationally complex problem in the PCL-PET fusion. In this paper we present some remarks concerning the nature of this computational complexity along with results of simulations showing complexity scaling with the changing simulation parameters. We also present our simulation software being developed for further analysis of the topic.

The aim of this paper is to evaluate performance of three radar system concepts that act as a sensor for ground based missile defence focused on defending an asset of critical importance. The signal model and processing scheme is presented and discussed. Appropriate multi-band fusion algorithms for collocated and dislocated sensors have been implemented and used to improve overall sensor efficiency. Obtained results illustrate possible benefits and limitations to system's performance. Implemented algorithms and created testbench will give chance to evaulate multi-band systems in more complicated scenarios.

In this article we discuss certain aspects of the algorithm for data processing in the PCL - PET passive radar system. We discuss the part of the fusion algorithm which is used for object tracking and estimate improvement. We also propose a method for bistatic measurements classification using the predicted object position and covariance matrices. Proposed algorithm is also suitable for asynchronous and random flow of input measurements. Presented algorithms, which are a work-inprogress, are being implemented and will be subject to further experiments and development on a PCL-PET system prototype.

In this article we discuss certain aspects of the algorithm for data processing in the PCL - PET passive radar system.We discuss the initial part of the fusion algorithm the main function of which is to provide the number of objects, their position estimations and the covariance matrix of these estimates. The measurement data model and processing scheme is presented and discussed. Presented fusion algorithms for dislocated sensors have been implemented and tested. Obtained results illustrate performance of overcoming difficulties arising in typical multi-static systems - ghost objects elimination and accurate position estimation. Presented algorithms are a work in progress and are being implemented and will be subject to further experiments and development on a PCL-PET system prototype.

In this article we discuss certain aspects of compressed sensing application in the context of radar systems. We thoroughly analyze the framework of the paper [4] and propose the directions of generalizations. In particular we consider a rectangle time frequency grid of non-prime type, non-Allotop carrier signals of the length non-equal to the length of time grid, incoherent carrier and grid frequency units. Finally we discuss the measurement aspects, stressing that the number of measurements may be smaller then the time grid of the time frequency plain. We present the results of simulations confirming that under some condition the compressed sensing performs well in our context.

The paper addresses important problems related to improvement of probability or equivalently an improvement of range of the detection of targets. The probability of detection of targets can be improved by fusion of noncoherent signals and/or plots from a few independents radars (channels) working in different bands. As an example multiband passive-active radar system working simultaneously in four bands is considered. The paper describes the concept of signal processing in this radar, similar to the MIMO method described in [1]. The fusion of signals is called centralised fusion (detection) and the fusion of plots is called decentralised fusion (detection). The signal processing algorithms described in the paper are based on the original concept that for the fusion of signals (i.e., the centralized fusion) the cueing method is used. It means that signals reflected from targets in multi bands are summed only if the targets have been detected by the decentralised fusion and are being tracked. Thus the centralised fusion takes place around the predicted target positions. The probability of detection versus range curves were calculated by a simulation process for the centralised and decentralised detection (fusion). Quantitative results of these simulations show the possibility for substantial improvement of the target detection probability or equivalently range and compared to singleband radar. (6 pages)

In this paper, the methodology of modelling the multiband radar based on radar equations for search and cued search radar is presented. This methodology was work out under assumption that the processing in each band is independent. Based on this methodology and real data of S/N from trials there were done appropriate calculations to have the parameters of the model of dual band radar (VHF, C band) in which each of band have the same range of detection of the same target with equal probability of detection.