FIELD: safety.
SUBSTANCE: invention relates to security alarm. Two-way radio-wave security alarm comprises transmitter, receiver, system of information collection and processing. Receiver comprises receiving antenna, detector, amplifier and control unit. Transmitter comprises heterodyne, modulator, pulse generator, control unit and transmitting antenna. Receiver additionally comprises mixer and heterodyne, wherein receiving antenna is connected to microwave amplifier, connected with mixer and then with detector and control unit of receiver, which is connected to heterodyne and then with mixer. Transmitter and receiver control units have feedback with system of information collection and processing. Security alarm operates as follows: transmitter emits electromagnetic waves in direction of receiver, which receives electromagnetic waves, converts them into electric signal and analyses this signal. Control unit of receiver sets microwave channel for heterodyne of transmitter, which is supplied to modulator; generator generates pulse sequence of certain ratio, specified by control unit of transmitter under action of pulses from controlled generator. Receiver control unit, which makes decision, determines state of output optoelectronic relay, as well as transmits data on current state over RS-485 bus or Ethernet interface to information collection and processing system.
EFFECT: technical result is simplification of operation, higher reliability and noise immunity, as well as higher probability of detecting intruder and reduced number of false alarms.
7 cl, 2 dwg
