PURPOSE: To provide a mobile object identification device of a simple constitution which can easily control the antenna directivity by providing a reflection/ shield plate to each interrogator.
CONSTITUTION: A case 10 of an interrogator main body contains an antenna, an oscillator means, etc., and a microstrip antenna 20 placed on a printed board is fixed at the upper inside of the case 10. The reflection/shield plates 31 and 31a made of a metal or dielectric mask the reflected radio waves and attached on both end faces of the case 10 with each spread of them. This spread angle B can be easily controlled by a control means 40. Thus it is possible to easily control the directivity of the antenna 20 by controlling the spread angles of both plates 31 and 31a.
NAGATA KAZUO
YOSHITAKE SATORU
TAKAI KIYOSHI
