| 摘要 |
<p>A system for localizing laid cables (C) or pipes by means of a system of transmitters comprising one or more fixed or mobile base stations (HS). At least one of the stations are provided with an electronic data processor and a number of relay stations (RS 1, RS 2, RS 3), some of which or all are fixed with exactly known geographic placements. Besides there are one or more measuring stations (MS) which can communicate with the base station (HS) and receive positioning signals from the relay station (RS 1, RS 2, RS 3). By request from a measuring station (MS) the base station (HS) can activate positioning signals from a selected group of relay stations (RS 1, RS 2, RS 3). The measuring station (MS) is provided with means of measuring the differences between the times of arrival of the signals from the activated relay stations (RS 1, RS 2, RS 3) and to re-transmit the measuring results to the base station (HS) which by means of the computer's memory converts the geographic data of the measuring result. In case cables (C) or pipes are laid, these data are entered into the data store, and in case a cable or a pipe is recovered the data are retransmitted to the measuring station (MS) together with such geographic information which is necessary for a complete orientation.</p> |
