Simulation and Implementation of an Integrated TDOA/AOA Monitoring System for Preventing Broadcast Interference

The rapid development of wireless broadband communication technology has degraded the location accuracy performance of radio monitoring stations worldwide that use signal angle of arrival (AOA) location technology, and the stations in Taiwan are no exception. In this study, a Federal Communications Commission F(50, 50) broadcast propagation prediction methodology was applied to determine the coverage area of installed TDOA-based monitoring stations in Tainan (i.e., southern Taiwan) metropolitan area. The simulation results indicated that 3 TDOA-based location stations are required to achieve a coverage diameter of 20~30 km. Subsequently, 3 TDOA-based radio monitoring stations [Luzhu, Tainan Gaote, and Tainan health stations (Jinkang)] were installed to locate the radio transmitter that was the source of broadcast interference in Taiwan by monitoring the frequency modulation of broadcast stations at 88.3, 91.5, 89.1, and 91.9 MHz in the Tainan metropolitan, rural, and urban areas, respectively. In this study, the proposed integrated TDOA/AOA location technology was implemented in Taiwan for the first time according to International Telecommunications Union requirements. The location accuracy was within 950 m (50% circular error probability) under multipath conditions in the metropolitan area.