The magnetic anti-theft system is a single-bit radio frequency identification system, and the modulation method adopted is the digital modulation method of amplitude keying (ASK). The alternating magnetic field emitted by the antenna, where the modulation signal is a binary coded signal, composed of a single-bit sequence in two states of 0 and 1.
The pulse sustain time is, the pulse off time is, the pulse period is 20ms, and the required pulse amplitude is larger ; The carrier signal is a 58kHz (or 60kHz, 68kHz) low-frequency sinusoidal signal; the modulated signal is an ASK signal with an amplitude modulation coefficient of 100%.