SOURCE LOCALIZATION: ALGORITHMS AND ANALYSIS

The time of arrival (TOA), time difference of arrival (TDOA), received signal strength (RSS), and direction of arrival (DOA) of the emitted signal are commonly used measurements for source localization. This chapter introduces two categories of positioning algorithms based on TOA, TDOA, RSS, and DOA measurements. The first class works on the nonlinear equations directly obtained from the nonlinear relationships between the source and measurements. The chapter presents corresponding examples, namely, nonlinear least squares (NLS) and maximum likelihood (ML) estimators. The second category attempts to convert the equations to be linear. The chapter discusses the linear least squares (LLS), weighted linear least squares (WLLS), and subspace approaches. It then presents the algorithm analysis, and explains two important performance measures, namely, mean and variance. The chapter also presents the computation of Cramér‐Rao lower bound (CRLB), which is a lower bound on the variance attainable by any unbiased location estimator.