Disturbance protection for wave-based measurement equipment for bodies in movement

摘要

The disturbance protection is for wave-based measurement equipment used for time-taking in motor sport. An infrared measurement technique is involved with a transmitter fitted on the vehicle to be time measured. A receiver is fitted at a point alongside the track on which the vehicle passes at a given time point. The spread angle (alpha) of the transmitter waves and the transmitter angle (beta) in relation to the horizontal plane together with the receiver height (4) from the ground plane conductive to a strong interference redn. The receiver part is provided with interference protecting side casings (b) placed in other directions to protect against outer waves. In the interval (d) where the receiver registers the transmitter waves as few as possible details are applied. The transmitter has a separate code or frequency nuance to avoid mixing of signals.