Description of the Cover Picture

The cover picture is taken from the article＂ An Optimal Sorting of Pulse Amplitude Sequence Based on the Phased Array Radar Beam Tasks＂ It shows the 3D pattern of 100 ＊ 100 phased array at elevation angle （0°, 0°）. This model is generated with MATLAB software and used to analyze the beam pointing of the antenna, and determine the normalized power by different colors. Then when the beam changes its direction continuously, the received pulse amplitude at a fixed point va- ries accordingly. In radar searching mode, by modeling and simulating the distribution variation of the power and analyzing its variation pattern at a certain coordinate point, it will help us to analyze the direction information of the radareffectively.

Method to reconnoiter pulse amplitude train for phased array radar based on Hausdorff distance

This paper presents a method to estimate beam pointing of phased array radar by the pulse amplitude train, which is significant in radar electronic reconnaissance and electronic support measure. Firstly, the antenna patterns modeling of the phased array system is exploited to build the radar sweeping model and the signal propagation model. Secondly, the relationship between the variation of the radiated power and the antenna beam pointing angles in the given airspace is analyzed. Based on the above two points, the sample with obvious amplitude characteristics of the pulse amplitude train can be screened out after detecting the train peaks. Finally, the sample is matched to the subsequent pulse amplitude train based on the Hausdorff distance. The proposed methods have less prior knowledge and higher efficiency and are easier to process. By cross correlating the sample of the pulse amplitude train with the sample data of the antenna follow-up radiation, the probability of detection of the beam pointing direction becomes larger in case that the subsequent antenna beam returns to the specific position.

Parameterized time-frequency analysis to separate multi-radar signals

Multi-radar signal separation is a critical process in modern reconnaissance systems. However, the complicated battlefield is typically confronted with increasing electronic equipment and complex radar waveforms. The intercepted signal is difficult to separate with conventional parameters because of severe overlapping in both time and frequency domains. On the contrary, time-frequency analysis maps the 1D signal into a 2D time-frequency plane, which provides a better insight into the signal than traditional methods. Particularly, the parameterized time-frequency analysis (PTFA) shows great potential in processing such non stationary signals. Five procedures for the PTFA are proposed to separate the overlapped multi-radar signal, including initiation, instantaneous frequency estimation with PTFA, signal demodulation, signal separation with adaptive filter and signal recovery. The proposed method is verified with both simulated and real signals, which shows good performance in the application on multi-radar signal separation.

An Optimal Sorting of Pulse Amplitude Sequence Based on the Phased Array Radar Beam Tasks

The study of phased array radar( PAR) pulse amplitude sequence characteristics is the key to understand the radar's working state and its beam's scanning manner.According to the principle of antenna pattern formation and the searching and tracking modes of beams,this paper analyzes the characteristics and differences of pulse amplitude sequence when the radar beams work in searching and tracking modes respectively.Then an optimal sorting model of pulse amplitude sequence is established based on least-squares and curve-fitting methods.This method is helpful for acquiring the current working state of the radar and recognizing its instantaneous beam pointing by sorting the pulse amplitude sequence without the necessity to estimate the antenna pattern.

Cognate pulse sorting method based on beam missions characteristics

In most multi-function phased array radar applications, multiple missions, including airspace searching and target tracking, are usually performed simultaneously by the digital beam-forming technique and the time dividing method. This paper presents a novel method to classify pulses of different missions from an interleaved pulse sequence emitted by the same radar, which is significant in radar electronic reconnaissance and electronic support measure. Firstly, two hypotheses, i.e., pulse relativity within the same mission and pulse independence among different missions, are proposed by analyzing the antenna pattern and the beam scheduling method of the phased array radar. Based on the above two hypotheses, an optimal model for pulse classification is exploited with pulse amplitude series, where the absolute-value sum of second order difference is taken as the optimal kernel to measure sequence smooth continuity. Finally, several pieces of sequences under different numbers of missions and tracking data rates are simulated for algorithm verification. The simulation results show that the long data length and the high data rate will increase classification efficiency due to the validity of the two hypotheses in sufficient pulse amplitude sequence.

A scheduling method based on a hybrid genetic particle swarm algorithm for multifunction phased array radar

为解决多功能相控阵雷达的任务调度难题,本文提出了一种融合粒子群算法、遗传算法和启发式交错算法的优化算法。通过混沌理论优化粒子群算法的飞行参数,设计动态惯性权重,并引入遗传算法中的交叉、变异操作,使该算法的计算效率和寻优能力均得到大幅度提高。在智能算法的框架下,提出启发式的交错调度算法可进一步利用任务等待期的时间资源。仿真结果表明,与现有方法相比,本文算法效率更高,鲁棒性更强。

Deceptive jamming discrimination based on range-angle localization of a frequency diverse array

针对电子对抗中的欺骗干扰鉴别问题,提出了基于频率分集阵列(frequency diverse array,FDA)的干扰鉴别方法。FDA波束具有距离—角度二维耦合特性,当波束聚焦距离与真实目标不一致时,会产生角误差信号,即干扰角度在相控阵中与真实目标一致,而在FDA中与真实目标不一致。因此,利用相控阵和FDA分别进行参数测量,比对测量结果即可实现干扰鉴别。提出了基于FDA进行干扰鉴别的具体流程,给出了两种双波束测量的实现方案,并对各方案的目标检测及参数估计性能进行了理论分析。仿真结果证明了该方法的有效性。