A Proposal of Location Estimation with Maximum likelihood Function using Joint PDF of Received Signals and prior Measured Signals

A novel location estimation with maximum log-likelihood function using joint probability function (PDF) of received signals and prior measured signals is proposed in order to improve the accuracy of the location estimation of mobile station (MS). We assume a spatial correlation between the received signals and the prior measured signals in the vicinity of the measured points. Using Bayesian theorem, a log-likelihood function is derived based on a new conditional PDF associated with a correlation. Computer simulation is carried out to clarify the improvement of the accuracy of the location estimation. It is shown that the estimation accuracy is improved by 25.4% with 16 prior measured points in 200 square meters as compared with that in case of conventional method