CAJ | 학술논문

针对运动目标源定位问题,提出了一种基于约束加权最小二乘(Constrained Weighted Least-Squares,CWLS)的时差频差定位算法.该算法利用目标源到达多个接收站的时差和频差信息,对目标源的位置和速度进行估计.通过引入中间变量,将时差频差非线性方程转换成伪线性方程(中间变量与目标源位置和速度之间存在约束关系),再对此约束条件引入拉格朗日乘子技术,将此伪线性方程的求解转化为求条件极值问题,创造性地求解了此非线性定位方程,提高了定位精度,并能满足实时性和全局收敛要求.仿真实验表明,该算法在保持相近复杂度的同时,进一步提高了定位性能,优于两步加权最小二乘算法,在噪声较高时仍然能达到克拉美罗下限
침대운동목표원정위문제,제출료일충기우약속가권최소이승(Constrained Weighted Least-Squares,CWLS)적시차빈차정위산법.해산법이용목표원도체다개접수참적시차화빈차신식,대목표원적위치화속도진행고계.통과인입중간변량,장시차빈차비선성방정전환성위선성방정(중간변량여목표원위치화속도지간존재약속관계),재대차약속조건인입랍격랑일승자기술,장차위선성방정적구해전화위구조건겁치문제,창조성지구해료차비선성정위방정,제고료정위정도,병능만족실시성화전국수렴요구.방진실험표명,해산법재보지상근복잡도적동시,진일보제고료정위성능,우우량보가권최소이승산법,재조성교고시잉연능체도극랍미라하한
By utilizing the time difference of arrival (TDOA)and frequency difference of arrival (FDOA)mea-surements of a signal received at a number of receivers,a constrained weighted least-squares (CWLS)algorithms for estimating the position and velocity of a moving source is proposed. By utilizing the Lagrange multipliers technique,the known relation between the intermediate variables and the source location coordinates can be ex-ploited to constrain the solution. And,on basis of convolute and polynomial rooting operations,the Lagrange multipliers can be obtained efficiently and robustly,which can allow real-time implementation as well as ensure global convergence. Simulation results show that the proposed estimator achieves remarkably better performance than the two-step weighted least squares(WLS)approach especially for higher measurement noise level,which makes the Cramér-Rao lower bound(CRLB)at a sufficiently high noise level before the threshold effect occurs possible.