Sun Zhongkang

Passive location using time of arrival along with direction of arrival and its changing rate

Passive location is a widely investigated problem. In this paper, a pseudo-linear algorithm for moving emitters passive location and tracking based on time of arrival (TOA), direction of arrival (DOA) and DOA changing rate measurements by a non-moving observer is given. This algorithm has high convergence speed and stability, so it is of great practicability. The observability conditions of location and tracking for moving emitters using TOA and DOA measurements are analyzed. Finally, the computer simulation results are presented.

Passive target tracking using marginalized particle filter

Abstract A marginalized particle filtering (MPF) approach is proposed for target tracking under the background of passive measurement. Essentially, the MPF is a combination of particle filtering technique and Kalman filter. By making full use of marginalization, the distributions of the tractable linear part of the total state variables are updated analytically using Kalman filter, and only the lower-dimensional nonlinear state variable needs to be dealt with using particle filter. Simulation studies are performed on an illustrative example, and the results show that the MPF method leads to a significant reduction of the tracking errors when compared with the direct particle implementation. Real data test results also validate the effectiveness of the presented method.

Passive location of fixed emitter using additional navigation information

Passive location is the determination of the position of an emitter from the available information obtained from the electromagnetic radiation. It is difficult for traditional measurements such as DOA only to determine the position of emitter quickly and accurately. How to make use of the available information from electromagnetic radiation is the key to improve the quality of passive location. A method of passive location is presented in this paper, which makes use of both DOA information and PRC (Phase Rate of Change) information obtained from electromagnetic radiation. The principle interpretation and derivation of algorithms, and the simulation and performance analysis of algorithms are presented.

A nonlinear optimized location algorithm for bistatic radar system

This paper discusses a nonlinear optimized location algorithm for bistatic radar system. The bistatic radar system proposed in the paper contains a T/R station and an R station. Generally, the T/R station provides data such as azimuth angle and distance, and in some circumstance, elevation of a target while the R station has measurements of azimuth angle and distance sum of the target. The coordinate transform is indispensable because of the long base line of a bistatic system. Thus five measurements transformed are presented for location resolution. Theoretically, 3-D location of a target requires only three independent measurements which correspond to three independent surfaces of position, therefore, it is possible to use this data redundancy to improve location accuracy. Some papers have discussed the location methods by means of measurement subsets division, GDOP analysis of measurement subsets, simplified LMS estimation (SLMS) or selecting the best subset (SBS) for solution. The SLMS method is based on the assumption that the relevance between every two different subsets is weak correlated to be neglected. In fact, it is not so. Data redundancy has not been sufficiently used in the SBS method. A nonlinear optimized method is presented in this paper which is based on the assumption that the change of GDOP in observation space of a T/R-R system is smooth that the weighted matrix of LMS estimation in the controlled observation area can be approached by means of nonlinear LMS learning method. Monte Carlo simulation test results of different methods are also given to show the improvement in location precision.

Utilization of the universal linearization in target tracking

The improved and generalized modified gain functions for target tracking are presented. Simulation results are presented which demonstrate the superiority of the new modified gain functions.

Passive location and tracking algorithm based on TOA and azimuth measurements for 3-D moving targets

This paper presents an algorithm based on TOA (time of arrival) and azimuth measurements. The location principle and feasibility of the technique are analysed in detail. For some bistatic radar systems with receivers which locate and track 3-D moving targets by means of a passive method, it is sometimes difficult to measure the pitch angle of targets. The algorithm proposed is of great importance to the practicability of bistatic passive location and tracking systems. With the help of computer simulation, the performance of this algorithm is evaluated for typical target paths according to Monte Carlo methods.<<ETX>>

Unbiased converted measurements for target tracking

The accurate debiasing processing for the bias in the classical conversion mainly depends on the first and second statistics of the cosine of the bearing measurement errors. An unbiased conversion is presented in this paper. Some comparison between the new unbiased conversion with the previously offered debiased conversion is made.

Data association in multitarget tracking with multisensor

One of the most important problem must be resolved in multitarget tracking with multisensor is the data association. It includes two folds: associating each observation of every sensor with each target, named scan association; associating-the track with track formed by different sensors, track association. There exist some difficulties in obtaining the models and in computing burden while tracking multitarget in a high density clutter environment. This paper presents an efficient method for tracking multitarget with multisensor, and the new method applied integer programming to associate the incoming measurements to established tracks. This paper assumes no new target appears and no target eliminates while the tracking goes on. Theory analysis and Monte Carlo simulations show the potential of this algorithm.

On the influence of coordinate transform upon measurement error of bistatic radar system

Coordinate transformation is always concerned with data processing of bistatic/multistatic systems. The influence of coordinate transformation upon measurement errors of the bistatic system is discussed in the paper. Detail derivations of the relation equation between the original coordinate system and the transformed new one, quantitative analysis of the influence and a number of curves are also given in the paper.

A joint probabilistic data association algorithm for distributed multisensor system in jamming and low-RCS target environment

Conventional target association and tracking techniques such as PDA and JPDA have very fine performance when the measurement acquired from sensors are perfect. However, when jamming and stealth techniques are widely used, it is very difficult for sensors to gain perfect measurements. Though a single sensor in a distributed sensors system might fail to acquire continually perfect measurements of low-RCS (stealth) targets under jamming environment, the distributed sensors system might gain relatively perfect measurements by integrating measurement hits or fractional trajectories of targets from every sensor in the system. The paper discusses association and tracking techniques under the circumstances mentioned above. Special attention is paid to track initiation and data association. Monte Carlo simulation test results are also presented in the paper.