Apparatus and method for detecting decrease in tire air pressure and program for detecting decrease in tire air pressure

摘要

An apparatus for detecting a decrease in a tire air pressure includes: a rotation velocity information detection means for periodically detecting tire rotation velocity information for the respective wheels of a vehicle; a frequency characteristic estimate means for estimating, based on this rotation velocity information, a frequency characteristic of the rotation velocity information; and a judgment means for judging, based on the estimated frequency characteristic, a decrease in the air pressure of the tire.