Tire resonance frequency detecting apparatus

摘要

Tire vibration frequency components of a left-hand and a right-hand tires (1a SIMILAR 1d) are derived from wheel speed signals (3a SIMILAR 3d) while a vehicle is traveling. A noise frequency component is detected based on a correlation between the vibration frequency components of the left-hand and right-hand tires (1a SIMILAR 1d) and the noise frequency component is reduced from the vibration frequency component. Thereafter, resonance frequencies of each tire are detected with using the vibration frequency component from which the noise frequency component is reduced and tire air pressures are detected on the basis of the resonance frequencies. <MATH>