(B2) ;SOKUDOKENSHUTSUKI

摘要

PURPOSE:To detect vehicle speed accurately through a simple ground facility. CONSTITUTION:Position signals having a predetermined frequency are transmitted from a loop antenna 4 comprising position signal transmitting sections and cancelling sections arranged repeatedly at a predetermined interval D. The position signals are detected, respectively, by a plurality(n) of receiving coils 12a-12c arranged on a vehicle at an interval of 2D/n and thus detected signals are delivered to a speed operating means 10 for every 2D/n distance. The speed operating means 10 operates a speed pulse based on the rising and falling of each received information for every D/n distance and then outputs thus detected speed pulse.