The conventional global positioning system (GPS) can often fail to provide position determination for a mobile user\nin indoor and urban environments. To cope with GPS failure in such environments, a new navigation system which\nutilizes a terrestrial digital multimedia broadcasting (T-DMB) signal to obtain the mobile user's position is presented.\nSince the T-DMB transmitters in Korea construct a single frequency network (SFN), which forces the transmitters to\nbe synchronized, the mobile user can measure a time difference of arrival (TDOA) for all audible T-DMB transmitter\npairs. The time difference between T-DMB transmitters is converted to a distance difference by multiplying the time\ndifference by the speed of light. Using these measurements and a TDOA positioning method, the mobile user\nposition can be estimated. An experiment with a T-DMB receiver and a data acquisition (DAQ) board is performed\nin Seoul to analyze the error characteristic of TDOA measurements. It is certified that the measurement error is\nbounded under 300 m and can be used to determine the mobile user's position with a small standard deviation.
Loading....