AN UNIT, A MANAGING DEVICE AND A METHOD OF TRANSMITTING amp; RECEIVING VEDIO amp; CONTROL SIGNAL FOR CCTV

摘要

The present invention relates to a method for transmitting and receiving a CCTV image and a control signal. The method is performed in a system for transmitting and receiving a CCTV image and a control signal, wherein the system comprises: a CCTV camera relay unit having k number of CCTV image and control signal transmitting and receiving units dually connected to a sequential image cable and a control cable; and a CCTV image and control signal transmission and reception managing device dually connected with both side ends of the CCTV camera relay unit respectively by an image cable and a control cable, and controlling the CCTV camera relay unit. The method includes a forward direction step where an image signal of each CCTV camera and system state information are sequentially-addition-multiplexed and relayed in a first direction, and a control signal of each CCTV camera is sequentially relayed in a second direction which is an opposite direction of the first direction. During the forward direction step, N^th number of the CCTV image and control signal transmitting and receiving unit receives a backward direction mode conversion signal from an immediate-post-device, or the transmission and reception directions of the image signal or the control signal of the first to N^th number of CCTV image and control signal transmitting and receiving units are converted to the opposite, respectively, when the CCTV camera control signal is not received from the immediate-post-device.