Monitoring front end (acquisition end) and notebook computer with CDMA network card. These terminals need to install special video decoding software to realize mobile monitoring function. The monitoring front-end system is mainly composed of signal acquisition equipment, general control action equipment, embedded digital hard disk video recorder, network video server and PC DVR with audio / video compression card. Signal acquisition equipment includes audio / visual signal, alarm signal acquisition equipment and other analog acquisition equipment, mainly composed of camera, sound pickup equipment, alarm, infrared probe, door magnet, smoke sensor, etc. its function is to provide various signal acquisition functions before monitoring, such as video, audio, dynamic, abnormal signal and related parameters; The action equipment that can be controlled includes electric zoom lens, motion, smoke, illegal intrusion and other outdoor electric control anti-theft devices Cover, spotlight switch and other controllable electromechanical equipment, which act according to the remote control command sent by the central control end; Embedded digital hard disk video recorder, network video server and PC DVR are the most important equipment in the whole system. They are responsible for encoding and compressing the collected analog signals such as audio / video and alarm into digital signals, and transmitting them to the computer room of the monitoring center through LAN, Internet or private network according to the standard network communication protocol. At the same time, it can also convert the digital control command sent by the computer room of the monitoring center into analog signal command and send it to electromechanical, alarm and other front-end equipment. The whole system can achieve unattended monitoring front-end and efficient monitoring operation.