K. Singh, M. Ismail, K. Jumari, M. Abdullah and K. Mat
Journal of Applied Sciences, 2008, 8(13), 2412-2419.
This study presents the development of techniques to estimate mobile user`s location (position) for Universal Intelligent Positioning System (UIPS) project. UIPS uses combination of available Location Determining Technologies (LDT) and newly developed techniques for UMTS (3G) or beyond networks. The usage of each LDT (technique) will determine Location Base Services QoS (accuracy of mobile user`s location). The new techniques developed are Close Circle Correlation (CCC) and Newton Raphsons 3 Circles (NR3C). Both techniques use time measurements observed from three Node B (base stations) in known Line of Sight (LOS) environment (multipath time delays are known). For unknown LOS environment, further enhancements on CCC technique and NR3C technique are developed, such as Averaging Estimator of CCC, First Mean Averaging Estimator of NR3C and Random Search Averaging Estimator of NR3C. The Cumulative Distribution Function of simulated results (simulation of actual data collected through drive test in UMTS network with known LOS) using NR3C technique produced 67% of the estimated user`s location error at 0 m and 95% of the estimated location error at 1.7 nm. Using CCC technique, produced 67% estimated location error at 2.04 m and 95% estimated location error at 3.2 m. NR3C produces better accuracy in known conditions of multipath delays. In unknown LOS conditions, Averaging Estimator of CCC produced 67% location error at 50.67 m and 95% error at 218 m, which is better than the other two enhanced (averaging) techniques of NR3C.
Information Technology Journal, 2012, 11(2), 283. DOI: 10.3923/itj.2012.283.288Location Determining Technique Using Signal Correlation Method in Suburban Environment
Journal of Applied Sciences, 2012, 12(1), 78. DOI: 10.3923/jas.2012.78.83