Energy-based source localization with non-ideal energy decay factor

Free-space propagation with the energy decay factor equal to two is often assumed in energy-based localization algorithms. In practice, non-ideal energy decay factors that are different from two can occur. This paper derives the Cramer-Rao lower bound (CRLB) for source localization with non-ideal energy decay factor and performs a sensitivity analysis of the localization algorithm presented in [K. C. Ho and M. Sun, 2007] with respect to the energy decay factor. The algorithm in [K. C. Ho and M. Sun, 2007] is found to be quite sensitive to the variations in the energy decay factor. This paper then proposes an extended algorithm for [K. C. Ho and M. Sun, 2007] that takes the non- ideal energy decay factor into account. Simulations show that the proposed solution reaches the CRLB accuracy for Gaussian noise as the signal-to-noise ratio tends to infinity.