Transmitting unit for anti-theft protection system for motor vehicle

摘要

The unit includes a transmitting antenna which emits HF oscillation, and a control unit which produces a periodical bipolar signal as a carrier oscillation, and which drives the transmitting antenna. The length of the pulse pauses is determined in the control unit in such way, that an amplitude of a fundamental oscillation of the emitted oscillation, as determined by Fourier analysis, is greater than 90 percent, and the amplitude of the third harmonic oscillation is less than 25 percent, compared with the amplitude of the fundamental oscillation of a rectangular oscillation without pulse pauses.