How Acousto-Magnetic (AM) Technology Works

Acousto-Magnetic systems transmit a magnetic frequency signal at 58 kHz in a pulsed pattern. The transmit signal energizes an acousto-magnetic tag in the detection zone. When the transmit signal pulse ends, the tag responds, emitting a single very distinctive frequency signal. The tag signal is at the same frequency as the transmitter signal.                                        

While the transmitter is off between pulses, a narrow band receiver detects the tag signal. A microcomputer checks the tag signal detected by the receiver to ensure it is at the right frequency and defined characteristics, occurs at a precise point in time synchronized to the transmitter, at the proper level, and at the correct repetition rate. If all of these criteria are met several times in a row, an alarm occurs.

The advantage of AM: the unique tag signature and the large tag signal produce the Acousto-Magnetic technology's wide surveillance coverage, high tag detection rate, and immunity to false alarms.