A Constrained Least Squares Approach to Mobile Positioning: Algorithms and Optimality

  • KW CheungEmail author
  • HC So
  • W-K Ma
  • YT Chan
Open Access
Research Article
Part of the following topical collections:
  1. Wireless Location Technologies and Applications


The problem of locating a mobile terminal has received significant attention in the field of wireless communications. Time-of-arrival (TOA), received signal strength (RSS), time-difference-of-arrival (TDOA), and angle-of-arrival (AOA) are commonly used measurements for estimating the position of the mobile station. In this paper, we present a constrained weighted least squares (CWLS) mobile positioning approach that encompasses all the above described measurement cases. The advantages of CWLS include performance optimality and capability of extension to hybrid measurement cases (e.g., mobile positioning using TDOA and AOA measurements jointly). Assuming zero-mean uncorrelated measurement errors, we show by mean and variance analysis that all the developed CWLS location estimators achieve zero bias and the Cramér-Rao lower bound approximately when measurement error variances are small. The asymptotic optimum performance is also confirmed by simulation results.


Measurement Error Variance Analysis Wireless Communication Quantum Information Error Variance 


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Copyright information

© Cheung et al. 2006

Authors and Affiliations

  1. 1.Department of Electronic EngineeringCity University of Hong KongKowloonHong Kong
  2. 2.Department of Electrical EngineeringNational Tsing Hua UniversityHsinchuTaiwan
  3. 3.Department of Electrical & Computer EngineeringRoyal Military College of CanadaKingstonCanada

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