The comparator which compares with

摘要

PROBLEM TO BE SOLVED: To provide a one-antenna milliwave radar equipment which can surely detect all targets at short distances.;SOLUTION: Radar equipment switches a single antenna 2 to the transmission side and reception side by means of a change-over switch 3. The equipment has a section in which the switch 3 is switched at a normal switching frequency and another section in which the switch 3 is switched at a higher switching frequency. The signal received by means of the antenna 2 is mixed with a transmitting signal f1 by means of a mixer 13 and with a transmission/reception switching signal fSW by means of another mixer 14 and only beat signal component fδ is fetched. A DSP 1 detects a target at a long distance when the normal switching frequency is used and detects the presence/absence of the target by extracting the beat signal component fδ by means of a comparator 21 when the higher switching frequency is used.;COPYRIGHT: (C)2000,JPO