| 摘要 |
<p>PURPOSE:To provide a signal processing device which receives the reflex echo generated when a target object reflects a transmitted wave from a transmission device and which measures with precision the time lag difference between the reflex echo signal and a synch. signal transmitted from the transmission device to a signal reception device. CONSTITUTION:Unnecessary direct waves 6b from a transmission device 1 may be included in a signal receiving means of a reception device 11 which is to receive the reflex echo 7 given by a target object 5, and reflex echo signals from the target object are extracted by an unnecessary signal suppressing means 15 which suppresses the signal components of the unnecessary direct waves 6b through utilization of the synch. signal transmitted from a transmission device 1 to the reception device via wire 8, and the delay time difference between the two signals is measured accurately by presuming the delay time with a time unit shorter than the sampling interval in A/D converter for the two signals the max. value of the absolute of the correlation function of the reflex echo signal and synch. signal.</p> |
