Position determination using the DTV segment sync signal

As a supplement to the Global Positioning System (GPS) in an urban center and indoor environment, the digital television (DTV) segment sync signal can be employed to obtain a mobile user’s position. Two DTV receivers and a counter are integrated to measure the time difference of arrival (TDOA) for a pair of received signals from a transmitter and its corresponding repeater (DTVR). Using the measurements from a transmitter and its multiple corresponding DTVR pairs, the mobile user position can be estimated using the recursive least square method. An experiment done in Seoul using two low-grade high resolution digital television (HDTV) receivers and a two-channel universal counter demonstrates that the mean value of the mobile user position measurement is accurate to 42.58 meters circular error probability (CEP).