Hybrid TDOA/AOA mobile user location for wideband CDMA cellularsystems

摘要

This paper proposes a mobile user location scheme for widebandncode-division multiple-access (CDMA) wireless communication systems. Tonachieve high location accuracy and low cost of the mobile receiver, thenlocation scheme combines the time difference of arrival (TDOA)nmeasurements from the forward link pilot signals with the angle ofnarrival (AOA) measurement from the reverse link pilot signal. High chipnrates in wideband CDMA systems facilitate accurate TDOA measurements,nand a smart antenna used at the home base station (BS) can providenaccurate AOA measurement in a macrocell environment. A two-step leastnsquare location estimator is developed based on a linear form of the AOAnequation in the small error region. Numerical results demonstrate thatnthe proposed hybrid TDOA/AOA location scheme gives a much highernlocation accuracy than TDOA only location, when the number of basenstations is small and/or when the TDOA measurements have a relativelynpoor accuracy