Analysis of downlink location methods for WCDMA and cdma2000

A simulation tool for studying the downlink trilateration method of a MS (mobile station) location in CDMA and TDMA systems has been developed. The primary function of this simulator is to determine the location accuracy in various situations (such as in urban, suburban and rural propagation environments) and to investigate various means of reducing the positioning errors. This tool simulates the signal received by the MS from the surrounding BSs (base stations), which is processed to obtain the TOA (time of arrival) or TDOA (time delay of arrival) estimate and then transmitted to the location estimator unit. The location estimator unit computes an estimate of the MS location. The simulator allows the testing of various methods and location estimators in several typical environments. We present the location accuracy and implementation complexity for WCDMA and cdma2000 systems. The WCDMA simulator is based on ARIB and ETSI WCDMA specifications and utilizes the IP-DL (idle period-downlink) algorithm. On the other hand, cdma2000 simulator is based on the TIA AFLT (advanced forward-link trilateration) specifications.