| 摘要 |
<P>PROBLEM TO BE SOLVED: To calculate a distance without causing large errors based on a free space propagation loss of received signal electric power even if under multi-path propagation surroundings. <P>SOLUTION: In a distance measuring device, a packet can be received by a receiver, a delay profile can be obtained using a correlation machine using a known reference signal of the packet. Only the direct wave electric power of its delay profile and predicted wave electric power are required. The distance can be obtained from the free space propagation loss using its direct wave electric power. Actually, when the sampling clock of the receiver is not so high, although delay waves are contained also in the direct wave and the predicted wave, since many of other delay waves are removed, accuracy can be enhanced. <P>COPYRIGHT: (C)2010,JPO&INPIT |
