Enhancement of Hearability in Geolocation Using Mobile WiMAX Network with Interference Cancellation and Long Integration

Abstract

Abstract:Together with the GPS-based approach, geolocation through mobile communication networks is a key technology for location-based service. Since the Mobile WiMAX system is considered as a candidate for fourth-generation mobile systems, it is important to investigate its location capability. The geolocation of Mobile WiMAX can be realized when the preamble symbols in the down-link channel are appropriately used for a TDOA (Time-Difference-of-Arrival) approach. However, the cellular structure of Mobile WiMAX inevitably generates co-channel interference, and it is difficult for the mobile terminal to acquire distance measurements from multiple base stations. Therefore, for geolocation via multilateration using the Mobile WiMAX network, it is very important to increase hearability. This paper proposes a geolocation method for Mobile WiMAX which employs interference cancellation and preamble signal overlapping for the enhancement of hearability. A novel interference cancellation strategy for complex-valued Mobile WiMAX signals is presented which has an iterative structure. Simulation results show that the proposed geolocation method provides the user's position with an accuracy of less than 20 m through the Mobile WiMAX cellular network if there is no multi-path or NLOS (None-Line-of-Sight). Keywords: WiBro, geo-location, interference cancelation

Performance Analysis of Assisted-Galileo Signal Acquisition Under Weak Signal Environment

“…동기 누적 방식은 신호의 주기적 특성을 이용 하여 일정 개수의 주기 신호를 누적하여 수신감도를 향상시 키는 기법이나, 동기 누적 이득을 높이기 위하여 동기 누적 길이를 길게 하면 주파수 부정합 오차가 증가한다 [5]. 주파수 부정합 오차의 영향을 줄이기 위하여 주파수 탐색 간격을 줄 이면 신호 획득에 필요한 계산량이 증가하는 단점이 있다 [6] II.…”