(1) using the microphone to collect the voice and the camera to collect the image signal, and the analog signal is converted to digital signal. The main processor compresses and enhances the voice and digital image signals, and then emits the compressed signal through a wireless signal transmitter;
(2) The control signals, such as the doorbell button and so on, are emitted by a wireless signal transmitter;
(3) The wireless signal receiver receives the wireless voice signal transmitted by the indoor machine, the main processor will receive the speech signal to decompress the processing, then the analog signal is converted into a digital model, which is played by the loudspeaker;
(4) The wireless signal receiver receives the indoor machine to transmit the control signal, the main processor converts the receiving control signal into the lock control command, and launches the unlock controller through a short distance wireless transmitter (usually using the ZigBee protocol).