Campus radio transmission method

transfer method

There are common campus broadcast transmission methods: audio cable fixed voltage (fixed resistance) transmission, wireless FM transmission, and cable FM transmission.

Pros and cons

â‘  The most commonly used cable is fixed-voltage audio twisted pair transmission: its advantages are cheap terminals and simple structure; the disadvantage is that every classroom needs wiring, the system is configured in strict accordance with the principles of power matching and impedance matching, and the scalability is poor, which cannot be achieved Stereo broadcasting, small program capacity (only one set of programs can be transmitted), it is impossible to broadcast different contents at the same time according to grade.

â‘¡Wireless FM transmission method: its advantages are simple construction, no wiring, low price, and multi-channel simultaneous broadcasting; the disadvantage is that it needs to occupy space frequency resources, in principle, it needs to be approved by the radio management department, which is susceptible to external interference and reliability Relatively poor.

â‘¢Wired coaxial coaxial cable FM transmission method: Cable FM is based on the transmission method of cable TV coaxial coaxial cable frequency division multiplexing technology. Its advantage is that it can realize multi-channel simultaneous transmission and strong scalability. As long as the terminal speaker meets the reception Just the level, not limited by quantity and power. Cable TV technology has experienced nearly 20 years of development history in China, and it is fully mature, with low-cost supporting products and stable performance. Cable FM broadcast can be transmitted together with closed-circuit VOD, dual control, closed-circuit TV, no wiring, simple construction, the number of transmission programs can be expanded, and intelligent broadcast addressable control functions can be realized; the disadvantage is that the cable FM transmission method is based on weak signals For transmission, the FM speaker needs an additional 220V AC power supply, and stable 220V AC power can be provided in each school classroom.

Based on the above several technologies, the general school should choose the cable FM transmission method. The cable FM broadcast has strong scalability, high cost performance, and can be combined with closed-circuit dual control, VOD on-demand teaching, campus multimedia and other "multi-network integration".