Xiao Shun-ping

Band Characteristics of SINR Polarization Filter

The band characteristics of the signal-to-interference-and-noise-ratio polarization filter to one signal in the presence of single noncoherent, purely polarized interference are investigated. The formulae of the filter band width on the polarization tracks and in the whole polarization region are presented. The quantitative description and the characteristic curves of the band scale are also given

Polarization target detection algorithm based on instantaneous Stokes sub-vector

Firstly, the statistics of random polarized waves instantaneous Stokes sub-vector is analyzed and its probability density function (PDF) is obtained. Secondly, the target detection problem is skillfully translated into the detection problem of three equivalent polarization signals. Thereby, a novel fusion detection algorithm is presented based on the difference statistical distribution of Stokes sub-vector between targets and clutters. Experimental results show that no matter the target is random polarization or invariable polarization, the algorithm is effective. Its performance can be comparative to that of the optimal polarization detector (OPD) and better than that of the polarization white filtering detector (PWF). Considering variable conditions of polarimetric measurements, it can be used more widely than the optimal polarization detector

Joint Spectrum estimation of Polarization and Space

The Joint Spectrum of Polarization and Space is constructed for the first time, which can depict the EM signal more completely. Based on the polarization sensitive antenna array, the joint spectrum is defined and the analytic function of joint spectrum is presented by MUSIC method. The discrimination power of joint spectrum is discussed theoretically in details. The polarization domain does not provide the same resolution capabilities as the other domains, when exploited alone. The simulations verify the superiority of the joint spectrum and coincide with the theoretical analysis. It is shown that the joint spectrum outperforms the spatial spectrum in characteristic detection and estimation.

Statistics of the Polarimetric Weibull-Distributed Electromagnetic Wave

The statistical properties of partially polarized light in Gaussian stochastic plane wave fields have been reported in the literature. In this paper, we examine the statistics of the stochastic plane electromagnetic (EM) wave fields that are Weibull distributed. The polarimetric Weibull-distributed wave is characterized by three parameters: the sum of the intensities of the two electric vector components, the orientation angle that the major axis makes with the reference coordinate system, and the ratio of the minor to the major axis. The joint and marginal probability densities of these random variables are determined as a function of the covariance matrix. The main properties of this important distribution are shown. Then, the statistical properties of the normalized Stokes parameters are described in detail in Weibull-distributed stochastic fields. The joint and marginal probability density functions of the three components of the normalized Stokes parameters are presented. Numerical simulations are operated, which coincide with the theoretical derivations. Comparisons between Gaussian and Weibull stochastic fields have been made. The presented statistics of the Weibull polarimetric wave will be useful to random medium scattering and speckle filtering, which can also be extended to deal with the characterization of the scattering matrix elements in radar polarimetry.

Fully polarized radar target scattering center extraction

A new method for fully polarized radar target scattering center extraction is proposed using Coherent Polarization Geometrical Theory of Diffraction (CP-GTD) model. Unlike the traditional single fixed-polarization GTD method, the new method can overleap the step of scattering centers association and can estimate coherent scattering matrices of scattering centers accurately. It also provides a better performance and a reduced computation burden because the full-polarization information is used. The superiority of the CP-GTD is verified by experiment results based on simulated data. The method can also be easily extended for SAR/ISAR.

The question and developing direction of the radar system vulnerability to ECM (RSVECM)

At present, the feasible and pressing task is to adequately make use of the limited actual data of and human beings limited knowledge on the fight mechanism of radar system vulnerability to ECM (RSVECM) to obtain a better rather than a best solution or objective function to RSVECM directly with the aggregation method. That is, the turning point of the dominance of utilizing the electromagnetic spectrum, and the basic index of radar anti-ECM is the relative improvement factor (RIF) which is determined mainly by the statistical result of computer dynamic course simulation.

New target detection method in strong active jamming background for polarimetric radar

A new method of target detection for polarimetric radar in the presence of strong active jamming is proposed. Based on analysis of the polarization characterizations of the signals received by polarimetric radar, the target detection is achieved through testing on the polarization information. Comparing with the traditional method of target detection made in time-frequency domain, the detection performance of the new method is improved because the influence of the strong active jamming is avoided. The performance of the new method is analyzed by simulation. Its validity is verified through outdoor experiment carried out by X-band polarimetric radar.

Spacial polarization characteristics of antenna

Based on interpreting the conception of antennas spacial polarization especially for instantaneous polarization detailedly, the description framework of spacial polarization characteristics for antenna is introduced in this paper. Some classical descriptors and instantaneous descriptors are given. On the basis of this, the spacial polarization characteristics of theoretical orthogonal dipole antenna and a practical jammer antenna is analyzed. The corresponding computer simulation is completed. The result indicates that antennas polarization characteristics often changes by rule in different radiation direction. The research in this paper also provide theoretical base and support for the application of the spacial polarization characteristics of antenna.

Analysis of radar detection performance for low altitude small target

Radar usually employs several signal processing methods successively for detection. Each processing step influences the radar detection performance. Thus, analysis of the radar detection performance considering the complete signal processing flow provides significant reference for radar detector design. In this paper, with the assumption that matched filtering, square-law detection, non-coherent integration, cell averaging constant false alarm rate detection and double-threshold detection are employed sequentially for radar detection, radar detection performance in K distributed sea clutter plus Rayleigh distributed thermal noise is analyzed. Mathematical expressions of radar false alarm probability and detection probability are derived. Radar detection performances for four types of Swerling fluctuating targets in various circumstances are presented by simulation. And comprehensive effect of K distributed sea clutter plus Rayleigh distributed thermal noise on radar detection performance is analyzed.

Experimental Study on Full-Polarization Micro-Doppler of Space Precession Target in Microwave Anechoic Chamber

Based on the background of radar target detection and recognition of space precession targets, an experimental study on full-polarization micro-Doppler of those targets is introduced. The wide-band scattering properties of space precession targets are analyzed, and then the theoretical full-polarization micro-Doppler models are proposed. The scenario of the experiment is introduced, and the measured data are analyzed, and then the differences of full-polarization micro-Doppler of different scattering structures can be observed during precession.