System-level simulation of a third generation WCDMA wireless geolocation network

Official URL: http://risc01.sabanciuniv.edu/record=b1063658 (Table of Contents)

A wireless geolocation system for use in a WCDMA network was simulated in Matlab. In such a system, the multipath delays have a significant effect on the mobile location estimate.Ü si ul nk end-to-end model was created according to WCDMA system specifications, where the pilot signal was spread using 28400-chip complex Gold spreading and passed through a shaping filter. The effects of multipath fading and noise was added. The received signal was passed through a receive filter and correlated with the mobile station's locally generated Gold code to find the multipath delay. The mobile location was estimated using a hyperbolic time-difference-of-arrival approach. The estimation error was calculated for various environments and channel models and found to be less than 20m for the suburban ATDMA model and less than 110m for the rural CODIT model, which is acceptable considering that one chip time corresponds to 78 m. For comparison, the former WCDMA specification of 40960-chip spreading was evaluated and an error of less than 100m was obtained for the COST-231 suburban model using the CODIT Macro Channel where one chip time corresponds to 73m. This asynchronous system was found to be a satisfactory geolocation system for WCDMA under the given conditions.