Optimization method of linear barrier coverage deployment for multistatic radar

To address the problem of building linear barrier coverage with the location restriction, an optimization method for deploying multistatic radars is proposed, where the location restriction splits the deployment line into two segments. By proving the characteristics of deployment patterns, an optimal deployment sequence consisting of multiple deployment patterns is proposed and exploited to cover each segment. The types and numbers of deployment patterns are determined by an algorithm that combines the integer linear programming(ILP)and exhaustive method(EM). In addition, to reduce the computation amount, a formula is introduced to calculate the upper threshold of receivers’ number in a deployment pattern. Furthermore, since the objective function is non-convex and non-analytic, the overall model is divided into two layers concerning two suboptimization problems. Subsequently, another algorithm that integrates the segments and layers is proposed to determine the deployment parameters, such as the minimum cost, parameters of the optimal deployment sequence, and the location of the split point. Simulation results demonstrate that the proposed method can effectively determine the optimal deployment parameters under the location restriction.

Cuckoo search algorithm-based optimal deployment method of heterogeneous multistatic radar for barrier coverage

This paper proposes an optimal deployment method of heterogeneous multistatic radars to construct arc barrier coverage with location restrictions.This method analyzes and proves the properties of different deployment patterns in the optimal deployment sequence.Based on these properties and considering location restrictions,it introduces an optimization model of arc barrier coverage and aims to minimize the total deployment cost of heterogeneous multistatic radars.To overcome the non-convexity of the model and the non-analytical nature of the objective function,an algorithm combining integer line programming and the cuckoo search algorithm(CSA)is proposed.The proposed algorithm can determine the number of receivers and transmitters in each optimal deployment squence to minimize the total placement cost.Simulations are conducted in different conditions to verify the effectiveness of the proposed method.

Signal and Data Processing of Television Based on Multistatic Radar Systems

A television based multistatic radar system is described. The commercial television transmitter is used as the illuminator in the multistatic radar system. The reflected commercial television signals are measured by an array of sensors. A data processing scheme is developed that adapts to the poor signal processing ability. The innovation is focused on the construction of the observation space, which could reduce the non linearity error. The new method leads to better system stability than the traditional one. Monte Carlo simulation is utilized and compared with the traditional method.

Deceptive jamming suppression in multistatic radar based on coherent clustering

This paper proposes a suppression method of the deceptive false target(FT) produced by digital radio frequency memory(DRFM) in a multistatic radar system. The simulated deceptive false targets from DRFM cannot be easily discriminated and suppressed with traditional radar systems. Therefore, multistatic radar has attracted considerable interest as it provides improved performance against deception jamming due to several separated receivers. This paper first investigates the received signal model in the presence of multiple false targets in all receivers of the multistatic radar. Then, obtain the propagation time delays of the false targets based on the cross-correlation test of the received signals in different receivers. In doing so, local-density-based spatial clustering of applications with noise(LDBSCAN) is proposed to discriminate the FTs from the physical targets(PTs) after compensating the FTs time delays, where the FTs are approximately coincident with one position, while PTs possess small dispersion.Numerical simulations are carried out to demonstrate the feasibility and validness of the proposed method.

Moving target localization for multistatic passive radar using delay, Doppler and Doppler rate measurements

Time delay and Doppler shift between the echo signal and the reference signal are two most commonly used measurements in target localization for the passive radar. Doppler rate, which can be obtained from the extended cross ambiguity function, offers an opportunity to further enhance the localization accuracy. This paper considers using the measurement Doppler rate in addition to measurements of time delay and Doppler shift to locate a moving target. A closed-form solution is developed to accurately and efficiently estimate the target position and velocity.The proposed solution establishes a pseudolinear set of equations by introducing some additional variables, imposes weighted least squares formulation to yield a rough estimate, and utilizes the function relation among the target location parameters and additional variables to improve the estimation accuracy. Theoretical covariance and Cramer-Rao lower bound(CRLB) are derived and compared, analytically indicating that the proposed solution attains the CRLB. Numerical simulations corroborate this analysis and demonstrate that the proposed solution outperforms existing methods.

Data fusion of target characteristic in multistatic passive radar

Radar cross section(RCS)is an important attribute of radar targets and has been widely used in automatic target recognition(ATR).In a passive radar,only the RCS multiplied by a coefficient is available due to the unknown transmitting parameters.For different transmitter-receiver(bistatic)pairs,the coefficients are different.Thus,the recovered RCS in different transmitter-receiver(bistatic)pairs cannot be fused for further use.In this paper,we propose a quantity named quasi-echo-power(QEP)as well as a method for eliminating differences of this quantity among different transmitter-receiver(bistatic)pairs.The QEP is defined as the target echo power after being compensated for distance and pattern propagation factor.The proposed method estimates the station difference coefficients(SDCs)of transmitter-receiver(bistatic)pairs relative to the reference transmitter-receiver(bistatic)pair first.Then,it compensates the QEP and gets the compensated QEP.The compensated QEP possesses a linear relationship with the target RCS.Statistical analyses on the simulated and real-life QEP data show that the proposed method can effectively estimate the SDC between different stations,and the compensated QEP from different receiving stations has the same distribution characteristics for the same target.

ANALYSIS OF TARGET TRACKING BASED ON RANGE DIFFERENCE MEASUREMENT OF MULTISTATIC RADAR SYSTEM

An analysis is presented for target tracking with short range multistatic radar system in this paper. The velocity vector is introduced into the model to depict target motion more precisely. The system measurement equation is such constructed on the basis of range difference that make the tracking model independent of the transmitter position. Therefore the algorithm is very much suitable for the case that the transmitter is not fixed. Simulation results show that the algorithm has the advantages of fast tracking and small steady tracking errors, and can be used for tracking target in short range with multistatic radar system.

A NEW METHOD FOR DETERMINING THE LOCATION AND LENGTH OF A THIN CYLINDRICAL TARGET WITH RANGE DIFFERENCE OF A MULTISTATIC RADAR SYSTEM

This paper describes a short range target location system based on the range difference information of a T-R4 multistatic radar system with FMCW signal. A new method is proposed to determine the location and length of a thin cylindrical target making use of the high resolution of wide band FMCW signal and the spectrum characteristics of the target echo. Formulae are derived for target location and its length estimation being independent of the transmitter position. System performances are simulated with the proposed algorithm and the results are given for various situations.

Impacts of space-time-frequency synchronization errors onwide-band target echo characteristics of bistatic/multistatic radar

Bistatic/multistatic radar has great potential advantages over its monostatic counterpart. However, the separation of a transmitter and a receiver leads to difficulties in locating the target position accurately and guaranteeing space-timefrequency synchronization of the transmitter and the receiver.The error model of space-time-frequency synchronization in a motion platform of bistatic/multistatic radar is studied. The relationship between the space synchronization error and the transmitter platform position, receiver platform position, moving state, and beam pointing error, is analyzed. The effect of space synchronization error on target echo power is studied. The target scattering characteristics are restructured by many separate scattering centers of the target in high frequency regions. Based on the scattering centers model of the radar target, this radar target echo model and the simulation method are discussed. The algorithm of bistatic/multistatic radar target echo accurately reflects the scattering characteristics of the radar target, pulse modulation speciality of radar transmitting signals, and spacetime-frequency synchronization error characteristics between the transmitter station and the receiver station. The simulation of bistatic radar is completed in computer, and the results of the simulation validate the feasibility of the method.

Detection, Identification and Tracking of Flying Objects in Three Dimensions Using Multistatic Radars

Multistatic radar systems can be used in many applications such as homeland security, anti-air defense, anti-missile defense, ship’s navigation and traffic control systems. Multistatic radars, which are capable of detecting and tracking flying objects in three-dimension coordinate systems, are simulated in this paper. The location and velocity of flying objects as well as their radar cross sections are computed. The object’s path is also estimated by tracking the object.

Multistatic radar analysis based on ambiguity function and Cramér-Rao lower bounds

The primary goal of this work is to characterize the impact of weighting selection strategy and multistatic geometry on the multistatic radar performance. With the relationship between the multistatic ambiguity function （AF） and the multistatie Cram6r-Rao lower bound （CRLB）, the problem of calculating the multistatic AF and the multistatic CRLB as a performance metric for multistatic radar system is studied. Exactly, based on the proper selection of the system parameters, the multistatic radar performance can be significantly improved. The simulation results illustrate that the multistatic AF and the multistatic CRLB can serve as guidelines for future multistatic fusion rule development and multistatic radars deployment.

多雷达组网抗干扰中的若干关键难题

雷达干扰因其实现了对雷达时、空、频等多域覆盖,且具有对雷达信号变化快速跟随能力,使单部雷达在干扰条件下靠自身抗干扰技术达到的作战效能被大大压缩。在体系化作战思维牵引下,利用多雷达组网工作是复杂干扰条件下提高雷达探测能力的有效途径之一,基于对雷达干扰的抗干扰技术途径分析,以多雷达组网探测为基础,分析了双/多雷达控制、状态、信息互联互通关系,重点提出了指挥控制关系、时空同步设计、信息互联等设计方法。同时参考开放式射频系统架构,提出了可动态配置的资源调度框架和流程,为多雷达组网在干扰条件下工作性能提升提供支撑。

非合作多基地雷达系统性能仿真分析

针对低RCS(radar cross section)的隐身舰船很难被普通的单基地雷达探测到的问题,提出了采用非合作多基地雷达系统对海上目标进行探测,创建了一个海上场景,其中多艘商船在S波段(3 GHz)发射电磁波,作为机会雷达;一艘护卫舰大小的军舰作为雷达系统接收机,目标假定为一艘货船和一艘隐身军舰。采用专业的电磁软件对海上目标进行仿真,计算普通货船和隐身军舰的双基地RCS数据,建立了MATLAB仿真模型,研究了非合作多基地雷达的探测覆盖范围。使用FEKO的双基地RCS仿真表明,通过改变发射机的数量和发射机到接收机之间的距离,找到一种最优的多基地雷达系统几何结构和系统配置。

分布式协同干扰对多基地雷达压制效能评估

针对战场多干扰机分布式协同压制目标多基地雷达作战效能问题,论文从多基地雷达探测原理出发,构建雷达方程和多机协同干扰方程,实现多机协同干扰效能分析。同时,针对实际应用中接收机位置未知,干扰对准发射机的情况,文章根据干扰机天线方向特性,分析动态协同干扰效能,并构建仿真场景,分析不同路径下干扰压制能力,为实际作战应用提供技术支持。

Angular glint calculation and analysis of radar targets via adaptive cross approximation algorithm

Angular glint is a significant electromagnetic （EM） scattering signature of extended radar targets. Based on the adaptive cross approximation （ACA） algorithm accelerated method of moments （MoM） and the plane incident wave assumption, the narrowband, wideband and newly developed high-resolution range profile （HRRP） based angular glint calculation formulations are derived and applied to arbitrarily shaped three-dimensional （3D） perfectly electrical y conducting （PEC） objects. In addition, the near-field angular glint is emphasized, which is of great importance for radarseeker applications. Furthermore, with the HRRP based angular glint, an approach to rigorously determine range resolution cel s which own relatively smal er angular glint is provided. Numerical results are presented with new findings to demonstrate the usefulness of the developed formulations.

ANALYSIS OF THE RETURNED SIGNAL MODEL IN BISTATIC RADAR SYSTEMS

Taking the relativistic effect of high velocity moving target into account, the Doppler shift, polarization deflection, reflection coefficient and phase delay of reflected electric field are analyzed rigorously under the assumptions that incident signal to the target is a plane wave and the target is a perfect conductor plane; and their analytic expressions are obtained. The present results are of practical significance to some extent for the accurate expression of the wideband returned signal of a high velocity moving target in the bistatic radar system and for the understanding of wideband ambiguity functions.

基于流向算法的协同雷达-NOMA通信系统布站优化

研究了协同雷达通信系统的布站优化问题,通信系统搭载在无人机(Unmanned Aerial Vehicle,UAV)上,采用非正交多址接入(Non-Orthogonal Multiple Access,NOMA)技术服务多个地面用户,雷达系统为多基地雷达,其多个接收机和发射机分置,雷达系统和通信系统存在部分频谱重叠共享。建立了UAV通信系统发射机和雷达接收机的联合布站优化模型,目标是在通信传输速率约束下,实现通信系统平均传输能耗最小化、通信发射机-雷达接收机信道的信噪比最大化以及雷达定位几何精度因子(Geometric Dilution of Precision,GDOP)最小化。引入流向算法(Flow Direction Algorithm,FDA)进行最优化求解,仿真结果表明,相对于通信系统未采用NOMA技术时,所提出的布站优化方案平均传输能耗更低,且FDA较其他常用智能优化算法的精度和寻优效率更高。

Joint compressed sensing imaging and phase adjustment via an iterative method for multistatic passive radar

The resolution of the multistatic passive radar imaging system(MPRIS)is poor due to the narrow bandwidth of the signal transmitted by illuminators of opportunity.Moreover,the inaccuracies caused by the inaccurate tracking system or the error position measurement of illuminators or receivers can deteriorate the quality of an image.To improve the performance of an MPRIS,an imaging method based on the tomographic imaging principle is presented.Then the compressed sensing technique is extended to the MPRIS to realize high-resolution imaging.Furthermore,a phase correction technique is developed for compensating for phase errors in an MPRIS.Phase errors can be estimated by iteratively solving an equation that is derived by minimizing the mean recovery error of the reconstructed image based on the principle of fixed-point iteration technique.The technique is nonparametric and can be used to estimate phase errors of any form.The effectiveness and convergence of the technique are confirmed by numerical simulations.

基于GNSS的多基地雷达目标定位与运动参数提取精度分析

基于GNSS的外辐射源雷达具备潜在的多基地雷达特性,聚焦基于GNSS的外辐射源雷达目标定位和运动参数提取精度分析,利用克拉美-罗下界分析目标定位和运动参数提取精度与卫星个数及目标回波信噪比之间的关系。仿真结果表明,卫星个数越多,目标定位与运动参数提取精度越高;当卫星数量相同时,不同卫星照射下目标回波信噪比相差越小,目标定位与运动参数提取精度越高。

一种针对目标三维跟踪的多基地雷达系统功率分配算法

针对实际应用中有效利用多基地雷达系统有限资源的需求,该文提出一种基于目标3维跟踪的功率分配方法。该方法首先推导了目标3维跟踪时均方根误差的贝叶斯克拉美罗下界,并将其作为代价函数进行功率分配。而后,该文用梯度投影算法对由此产生的非线性、凸优化问题进行了求解。仿真结果表明,相对于功率均匀分配的情况,该文提出的功率分配方法能明显提高目标的跟踪精度。