Radar Performance Evaluation Research Articles

MCRB on DOA Estimation for Automotive MIMO Radar in the Presence of Multipath

Autonomous driving and advanced active safety features require accurate high-resolution sensing capabilities. Automotive radars are the key component of the vehicle sensing suit. However, when these radars operate in proximity to flat surfaces, such as roads and guardrails, they experience a multipath phenomenon that can degrade the accuracy of the direction-of-arrival (DOA) estimation. Presence of multipath leads to misspecification in the radar data model, resulting in estimation performance degradation, which cannot be reliably predicted by conventional performance bounds. In this paper, the misspecified Cramér-Rao bound (MCRB), which accounts for model misspecification, is derived for the problem of DOA estimation in the presence of multipath which is ignored by the estimator. Analytical relations between the MCRB and the Cramér-Rao bound are established, and the DOA estimation performance degradation due to multipath is investigated. The results show that the MCRB reliably predicts the asymptotic performance of the misspecified maximum-likelihood estimator and therefore, can serve as an efficient tool for automotive radar performance evaluation and system design.

A Classifying-Inversion Method of Offshore Atmospheric Duct Parameters Using AIS Data Based on Artificial Intelligence

Atmospheric duct parameters inversion is an important aspect of microwave-band radar and communication system performance evaluation. AIS (Automatic Identification System) is one of the signal sources used for atmospheric duct parameters inversion. Before the inversion of atmospheric duct parameters, determining the type of atmospheric duct plays an important role in the inversion results, but the current inversion methods ignore this point. We outlined a classifying-inversion method of atmospheric duct parameters using AIS signals combined with artificial intelligence. The method consists of an atmospheric duct classification model and a parameter inversion model. The classification model judges the type of atmospheric duct, and the inversion model inverts the atmospheric duct parameters according to the type of atmospheric duct. Our findings demonstrated that the accuracy of the atmospheric duct classification model based on deep neural network (DNN) even exceeds 97%, and the atmospheric duct parameters inversion model has better inversion accuracy than that of the traditional method, thereby illustrating the effectiveness and accuracy of this novel method.

Multiprobe Radiation Simulation Method for Phased Array Radar Performance Evaluation

The phased array radar exhibits improved tracking accuracy and anti-jamming performance with multi-beam tracking, beam agility, and adaptive beam-forming capabilities. The performance evaluation of the phased array radar is essential for the product designing and development stage. However, the conventional injection simulation and triad radiation simulation methods are not suitable for phased array radars. Therefore, new methods for radiation simulation are required on an urgent basis for the performance evaluation of phased array radars in a reliable, reliable, and repeatable way. This paper focuses on designing a practical anechoic chamber system of multi-probe radiation suitable for phased array radars. The appropriate test distance, the physical size of the anechoic chamber, the multi-probe radiation signal model, and the number of probes required were discussed. Furthermore, an inversion method based on least squares was proposed to solve the complex weights of the probes, thereby simulating the desired apparent center position. The simulation results demonstrated the effectiveness of the proposed method.

Modelling of the anti-tank guided missile scattering field and radar performance evaluation in terms of missile detection

The study presents the results achieved in an analysis of the variation of the level of an echo signal generated by the FGM-148 Javelin anti-tank missile, received by the active protection system radar with consideration given to the target attack flight profile. For our study, we use the results of modelling of the missile’s scattering field at frequencies of 1, 3, 6, and 10 GHz using the Altair FEKO CAD suite. According to estimated data, a radar using the frequency-modulated signal and operating at a medium radiation power of up to 1 W is able to detect a missile at a distance of at least 1,000 m. The results show that a combination of low power and a continuous broadband signal (100…150 MHz) along with coherent integration to units of seconds ensures concealed operations of the active protection system radar (estimated range of its radiation detection by a reconnaissance radar is not greater than 10 km).

Performance Evaluation of Radar against Complicated E.M. Environment Based on AHP

The performance of current radars is degraded in complicated E.M. environment and there is no uniform method to make evaluation to the performance degradation till now. Aiming at certain 3D radar in specific combat scenario, the paper provided the specification system for performance evaluation of radar against complicated E.M. environment, established the evaluation model and conducted normalization processing to specifications through AHP and made quantitative evaluation. The simulation results indicate that the established model by that method is effective and feasible and the evaluation result can provide reference for performance evaluation of radar against complicated E.M. environment.

Analytical Model and Real-Time Calculation of Target Echo Signals on Wideband LFM Radar

In wideband radar system testing and performance evaluation, target echo simulation should simultaneously meet real-time and high-precision requirements. In this paper, we focus on the wideband linear frequency modulated (LFM) radar signal, derive the echo signal time-domain analytical expression based on the multiscattering center model and propose a high-precision real-time echo simulation calculation method. Regarding the low model reliability and poor versatility problems in the current wideband radar target calculation, the analytical model proposed here truly reflects the inner-pulse modulation characteristics of the radar transmit signal and the wideband electromagnetic scattering characteristics of the target. Current wideband radar target signal calculation accuracy and real-time performance are also difficult to balance. Considering this problem, the wideband radar target echo analytical model proposed in this paper avoids the large amount of calculations required for the full numerical calculation and effectively improves the calculation accuracy and real-time performance of wideband radar target echo signal calculations without reducing calculation accuracy. The real-time calculation method involves elaborate amplitude-phase control. Simulation analysis and experimental verification confirmed the reliability and validity of these results. These research results have important theoretical significance and practical application value in the field of hardware-in-the-loop simulation.

Correlation coefficients of Pythagorean hesitant fuzzy sets and their applicationto radar LPI performance evaluation

Correlation coefficients of Pythagorean hesitant fuzzy sets and their applicationto radar LPI performance evaluation

Radar seeker performance evaluation based on information fusion method

Radar seeker is responsible for transmitting the dynamic position information of the target back to the weapon control center in the guidance phase. It is of great engineering significance to evaluate the anti-jamming ability of radar seeker in the anti-jamming environment Aimed at obtaining more reasonable evaluation result, an evaluation method based on information fusion is proposed against the background of angle measurement performance in this paper. Radar seeker performance test have many stages with different characteristics. Information fusion has advantages in radar performance evaluation which takes advantage of measured data obtained in different stages rather than process them respectively. Furthermore, we studied two specific issues in the information-fusion stage. The first problem is about consistency testing between different information using K-L information distance measurement, which is the premise of information fusion. The second problem is about the information weights calculation by PLT criterion, which can take sample size into account. Information fusion can make full use of the multi-source test information to obtain more reliable evaluation conclusion. Experimental results prove the effectiveness of the proposed method.

MIMO radar target localization and performance evaluation under SIRP clutter

Multiple-input multiple-output (MIMO) radar has become a thriving subject of research during the past decades. In the MIMO radar context, it is sometimes more accurate to model the radar clutter as a non-Gaussian process, more specifically, by using the spherically invariant random process (SIRP) model. In this paper, we focus on the estimation and performance analysis of the angular spacing between two targets for the MIMO radar under the SIRP clutter. First, we propose an iterative maximum likelihood as well as an iterative maximum a posteriori estimator, for the target's spacing parameter estimation in the SIRP clutter context. Then we derive and compare various Cramér–Rao-like bounds (CRLBs) for performance assessment. Finally, we address the problem of target resolvability by using the concept of angular resolution limit (ARL), and derive an analytical, closed-form expression of the ARL based on Smith's criterion, between two closely spaced targets in a MIMO radar context under SIRP clutter. For this aim we also obtain the non-matrix, closed-form expressions for each of the CRLBs. Finally, we provide numerical simulations to assess the performance of the proposed algorithms, the validity of the derived ARL expression, and to reveal the ARL's insightful properties.

Performance Evaluation of a Pulse-Doppler Radar with Digital IF Using Modern Technical Computing and CAD Tools

In this paper, we build an approach for radar systems performance evaluation using modern CAD tools. In fact, modern system engineering software environments present many radar models that can be taken as a reflection track. This work tries to follow the radar signal trough the different subsystems of a pulse-Doppler radar, from the waveform generation until the detection probability computation. To give more robustness to this process, the signal flow analysis is accompanied with equation based evaluation. The analyzed system was designed by our team starting from an Agilent SystemVue model whose computations were done by a MATLAB script. In fact, the whole Data Flow (DF) simulation is controlled by this script which gathers all the mathematical analysis which is ‘behind’ the model. Really, this mathematical chain permits the reader to understand the simulation and to predict the results. Progressing in a ‘whole’ process, our approach combines the theory and computation with functional description which gives a sense to the ‘numbers’. In addition, this ‘wholeness’ is reinforced by integrating signal visualization graphics that permit the reader to make a synthetic view on the signal shapes and so, to understand the system operation. This implies the use of software instrumentation within the DF simulator. All these analysis components (functional, mathematical and simulation based) are guided by an evaluation criterion: the detection probability. This work is very useful in all the radar system life cycle steps (design, operation and maintenance) because it contributes to cost reduction and operational effectiveness.

Applications of generalized rough set theory in evaluation index system of radar anti-jamming performance

Radar anti-jamming performance evaluation is a necessary link in the process of radar development, introduction and equipment. The applications of generalized rough set theory are proposed and discussed in this paper to address the problems of big data, incomplete data and redundant data in the construction of evaluation index system. Firstly, a mass of real-valued data is converted to some interval-valued data to avoid an unacceptable number of equivalence classes and classification rules, and the interval similarity relation is employed to make classifications of this interval-valued data. Meanwhile, incomplete data can be solved by a new definition of the connection degree tolerance relation for both interval-valued data and single-valued data, which makes a better description of rough set than the traditional limited tolerance relation. Then, E-condition entropy-based heuristic algorithm is applied to making attribute reduction to optimize the evaluation index system, and final decision rules can be extracted for system evaluation. Finally, the feasibility and advantage of the proposed methods are testified by a real example of radar anti-jamming performance evaluation.

AN INSAR PERFORMANCE EVALUATION METHOD BASED ON VIRTUAL PROMINENT SCATTERERS

AbstractAn improved interferometric synthetic aperture radar (InSAR) performance evaluation method based on prominent scatterers (PS) is proposed to precisely assess the accuracies of the absolute/relative interferometric phase and the absolute/relative height. The critical technical defect of the conventional PS‐based method is analysed, where overvalued performance indexes are caused by higher coherence on the PS than on the ordinary ground scene. Virtual prominent scatterers (VPS) around the actual PS are introduced and treated as statistical samples when the indexes are computed. The pixel location of the VPS is estimated indirectly by utilizing the high signal to clutter ratio of the VPS and the accurate relative location between the PS and the VPS. A spaceborne InSAR signal simulation experiment is carried out to validate the new VPS‐based method. The developed method can support performance analysis, error isolation and troubleshooting in InSAR systems.

Evaluation method for radar anti-stealth performance based on evidence fusion

Aiming at the phenomenon of complicated process and imperfect algorithm in the evaluation of radar anti-stealth performance,a new method for the evaluation based on improved evidence theory was presented. Firstly,to overcome the shortcomings of strong subjectivity and weak correlation,the credibility assignment function was corrected in real time according to the relationship among credibility factor,entropy weight and supported coefficient,which is based on the objective analysis of entropy theory and Euclidean distance.Secondly,combined with the multi-hierarchy indexes of radar anti-stealth performance,the rank order of whole radars anti-stealth performance on utility interval was attained. At last,an objective and accurate assessment results were obtained. The analysis of theory and simulation proved that,in contrast to other fusion algorithm,the improved fusion algorithm had better ability of assessment and better robustness.

Performance evaluation of lunar penetrating radar onboard the rover of CE-3 probe based on results from ground experiments

Lunar Penetrating Radar (LPR) onboard the rover that is part of the Chang'e-3 (CE-3) mission was firstly utilized to obtain in situ measurements about geological structure on the lunar surface and the thickness of the lunar regolith, which are key elements for studying the evolutional history of lunar crust. Because penetration depth and resolution of LPR are related to the scientific objectives of this mission, a series of ground-based experiments using LPR was carried out, and results of the experimental data were obtained in a glacial area located in the northwest region of China. The results show that the penetration depth of the first channel antenna used for LPR is over 79 m with a resolution of 2.8 m, and that for the second channel antenna is over 50.8 m with a resolution of 17.1 cm.

Analysis of Quantum Radar Cross Section and Its Influence on Target Detection Performance

Quantum radar is a new detection technology based on the mechanism of quantum physics and is promising for enhancing radar target detection capability. In this letter, the quantum radar equation is established based on the traditional radar equation; meanwhile, how the quantum radar cross section (QRCS) influences target detection performance and how QRCSs for some typical targets distribute are investigated via simulations. Simulation results demonstrate that the signal-to-noise ratio increases with the QRCS, the peak values of side-lobes of the QRCS for the cylinder surface fluctuate little, and the QRCS for corner reflectors almost exhibits no variations in a wide range of incident angles. The results listed above can benefit the signal design and performance evaluation of quantum radar as well as the design of quantum stealthy targets.

Design and Implementation of Radar Cross-Section Models on a Virtex-6 FPGA

The simulation of radar cross-section (RCS) models in FPGA is illustrated. The models adopted are the Swerling ones. Radar cross-section (RCS) which is also termed as echo area gives the amount of scattered power from a target towards the radar. This paper elucidates the simulation of RCS to represent the specified targets under different conditions, namely, aspect angle and frequency. This model is used for the performance evaluation of radar. RCS models have been developed for various targets like simple objects to complex objects like aircrafts, missiles, tanks, and so forth. First, the model was developed in MATLAB real time simulation environment and after successful verification, the same was implemented in FPGA. Xilinx ISE software was used for VHDL coding. This simulation model was used for the testing of a radar system. The results were compared with MATLAB simulations and FPGA based timing diagrams and RTL synthesis. The paper illustrates the simulation of various target radar cross-section (RCS) models. These models are simulated in MATLAB and in FPGA, with the aim of implementing them efficiently on a radar system. This method can be generalized to apply to objects of arbitrary geometry for the two configurations of transmitter and receiver in the same as well as different locations.

IEEE Radar standards and the radar systems panel

Institute of Electrical and Electronic Engineers (IEEE) Radar standards were created to uniquely define terminology associated with the development, characterization, and utilization of radar systems. The radar standards are essential tools utilized by the radar community to enable clear and concise communication of radar aspects and facilitate the specification and evaluation of radar performance. The AESS Radar Systems Panel (RSP) consists of a group of experts in the field of radar who promote various radar related activities such as the IEEE Radar Conferences, student education initiatives, and many more benefiting the radar community. One of the lesser known RSP activities is the development and maintenance of radar related standards. The two radar standards sponsored by the RSP are the IEEE Standard (STD) 521, IEEE Standard Letter Designations for Radar Frequency Bands [1], and IEEE STD 686, IEEE Standard Radar Definitions [2]. Another radar related standard that is not sponsored by the RSP but includes several RSP members on the working group is IEEE STD 1672, IEEE Standard for Ultrawideband Radar Definitions. The radar standards provide essential tools for radar engineers specifying, developing, and evaluating radar system performance.

Performance evaluation of radar and satellite rainfalls for Typhoon Morakot over Taiwan: Are remote-sensing products ready for gauge denial scenario of extreme events?

summary This study evaluated rainfall estimates from ground radar network and four satellite algorithms with a relatively dense rain gauge network over Taiwan Island for the 2009 extreme Typhoon Morakot at various spatiotemporal scales (from 0.04 to 0.25 and hourly to event total accumulation). The results show that all the remote-sensing products underestimate the rainfall as compared to the rain gauge measurements, in an order of radar (� 18%), 3B42RT (� 19%), PERSIANN-CCS (28%), 3B42V6 (� 36%), and CMORPH (� 61%). The ground radar estimates are also most correlated with gauge measurements, having a correlation coefficient (CC) of 0.81 (0.82) at 0.04 (0.25) spatial resolution. For satellite products, CMORPH has the best spatial correlation (0.70) but largely underestimates the total rainfall accumulation. Compared to microwave ingested algorithms, the IR-dominant algorithms provide a better estimation of the total rainfall accumulation but poorly resolve the temporal evolution of the warm cloud typhoon, especially for a large overestimation at the early storm stage. This study suggests that the best performance comes from the ground radar estimates that could be used as an alternative in case of the gauge denial. However, the current satellite rainfall products still have limitations in terms of resolution and accuracy, especially for this type of extreme typhoon.

다채널 직접 디지털 합성을 이용한 레이더 반사 신호 모의 장치

레이더는 표적으로부터 반사된 신호의 크기, 도플러 속도로부터 표적의 거리, 속도 정보를 알 수 있으며, 이런 반사 신호의 특징들은 표적의 반사 특성과 기동에 의해 결정된다. 표적의 위치 정보에 대한 각도 오차는 합채널에 대한 차채널의 크기 비로부터 추출된다. 본 논문에서는 다기능 레이더의 성능을 평가하고 분석하기 위한 레이더 반사 신호 모의 장치(RSSE)에 대해 소개하였다. 개발된 레이더 반사 신호 모의 장치는 다채널 직접 디지털 합성(MC-DDS)을 이용하여, 재밍 신호를 포함한 다중 표적 환경을 모사할 수 있도록 구현되었으며, 효율적인 하드웨어 구조 설계를 통해 모사할 수 있는 표적의 수를 용이하게 확장할 수 있도록 설계되었다. 개발된 모의 장치의 요구 성능 및 기능을 시험 환경에서 확인하였으며, 신호 처리기(RSP)와의 연동 시험 구성에서 표적 탐지 성능을 입증하였다. Radar receiving echo signal provides target information - range, velocity and position by signal magnitude and Doppler shift, which are determined by target reflection characteristics and target maneuver. Target angle error is extracted from the magnitude ratio of difference channel to sum channel. In this paper, we introduce a radar Return Signal Simulation Equipment(RSSE) which is implemented for the purpose of performance analysis and evaluation of phased array multi-function radar(MFR). It generates multi-target environment with jamming signals using MC-DDS (Multi-Channel Direct Digital Synthesis), and has scalability by using the efficient hardware configuration. The performance of the developed RSSE has been evaluated under various test environments. Especially, we proved that required target detection performance is achieved by RSP(Radar Signal Processor) interfaced RSSE configuration.

Performance Evaluation of Radar and Decoy System Counteracting Antiradiation Missile

Considering the pattern, polarization, and propagation characteristics, a method for modeling the radiation field of radar and decoy is described. Based on the mechanism of two-channel direction-finding systems with a four-arm spiral antenna, the generating model of the guidance signal related to the superposed field radiated by the antennae of the radar and the decoys is presented. By introducing a simplified movement model of an antiradiation missile, the dynamic simulation algorithms and formulas for analyzing deception effects are proposed. The effects of the initial phases, the time sequence, and the signal waveform on the survival probabilities of the radar and the decoys are discussed briefly. Numerical results show that high survival probabilities of the radar and the decoys can be obtained when three decoys have been distributed near the radar in an appropriate quadrangular topology, in which the distances between the radar and the decoys are about 350 m and the decoy level is slightly higher than the average side lobe level of the radar.