Hybrid location determination techniques in heterogeneous network
Heterogeneous networks are developed to allow communication devices to access the wireless network using different access technologies. In heterogeneous networks, group of networks can be used to provide particular services. Every service can be delivered to the user using the optimum network for that service. Mobile positioning is an important service that can be offered by heterogeneous networks by using the resources of the cellular system to determine the location of a mobile station. However, the accuracy of the localization is subjected to the Location Determination Techniques (LDT) adopted such as Time-of-Arrival (TOA), Time Difference-of-Arrival (TDOA) and Enhanced Observed-Time-Difference (E-OTD), and signal hearability. This work analyzes appropriate LDT and proposing a hybrid algorithm under low hearability condition for heterogeneous network. Two simulations have been implemented for these purposes, the first one is single layer cellular network system which is used to evaluate and compare various LDT techniques under different mobility models. The second simulation has been implemented to evaluate the proposed hybrid algorithm and compare it with several LDT techniques considering the accuracy of location measurements. The results show that the LDT error for hybrid technique is better as compare to TDOA and E-OTD at 67% and 95% of the cumulative density functions (CDF).