A study of ambiguity in hyperbolic mobile position location

The paper investigates the conditions in which the MS position estimation is subjected to ambiguous solutions when using the hyperbolic trilateration method in cellular systems. Given the BTSs positions, a mathematical framework based on the measurements of range differences is developed in order to map the ambiguity region. Evaluation of the size of this region with respect to the hearabilty area is performed, and under this viewpoint a comparison between different geometric arrangements of BTSs is made.