PURPOSE: To acquire simultaneously a video having good resolving power at a near range and a video having good sensitivity at a remote range by transmitting plural pulse radio waves different in widths one by one at every trigger, amplifying the received signals respectively in different band widths, selecting the signals by as much as for the respectively different specified periods within the trigger period, and outputting the same.

CONSTITUTION: The received signal reflecting from a target pass through a BPF8 in the trigger period when short pulses are transmitted by switch circuits 7, 10 and 12 and said signal is outputted to a terminal P6 only in the period O-T1 within said trigger period. The signal passes through a BPF9 in the trigger period when long pulses are transmitted and said signal is outputted to the terminal P6 only in the period T1-T2 within said trigger period. More specifically, the video signal for the transmission of the short pulse radio wave is obtd. at a near distance (in the range corresponding to the period O-T1) and the video signal for the transmission of the long pulse radio wave at a remote distance (the range corresponding to the period T1-T2) are respectively obtd. at every trigger.