Wireless transmission goes through two stages: analog and digital transmission.  Analog image transmission has been basically eliminated in many industries due to its interference and co-channel interference and noise superposition, resulting in poor effect in practical applications.

With the maturity of OFDM technology and components, products using COFDM technology have become the most advanced wireless transmission equipment. Its advantages are as follows:

1、It is suitable for application in None-line-of-sight and obstructed environments such as urban areas, suburbs, and buildings, and shows excellent "diffraction and penetration" ability.

COFDM wireless image equipment has the advantages of "non-line-of-sight" and "diffraction" transmission due to its multi-carrier and other technical characteristics，In urban areas, mountains, inside and outside buildings and other environments that cannot be seen and obstructed, the device can achieve stable transmission of images with a high probability, and is not affected by the environment or is less affected by the environment.

Omnidirectional antennas are generally used at both ends of the transceiver and receiver, and the system deployment is simple, reliable, and flexible.

 

2、It is suitable for high-speed mobile transmission, and can be applied to vehicles, ships, helicopters/drones and other platforms.

Traditional microwave, wireless LAN and other devices cannot independently realize the mobile transmission of the transceiver end and can only realize the transmission of mobile point to fixed point under certain conditions. Its system has many technical links, complex engineering, reduced reliability, and extremely high cost.

However, for COFDM equipment, it does not require any additional devices, it can realize the use of fixed-mobile, mobile-mobile rooms, and is very suitable for installation on mobile platforms such as vehicles, ships, helicopters/drones, etc. The transmission has high reliability and high-cost performance.

 

3、It is suitable for high-speed data transmission, generally greater than 4Mbps, to meet the transmission of high-quality video and audio.

In addition to the requirements for cameras, high-quality video and audio have very high requirements for encoding streams and channel rates, and each subcarrier of COFDM technology can choose QPSK, 16QAM, 64QAM and other high-speed modulation, and the synthesized channel rate is generally greater than 4Mbps. Therefore, it can transmit 4:2:0, 4:2:2 and other high-quality codecs in MPEG2, and the image resolution of the receiving end can reach 1080P, which meets the requirements of post-analysis, storage, editing and so on.

 

4、In complex electromagnetic environments, COFDM has excellent immunity to interference.

In a single-carrier system, a single fading or interference can cause the entire communication link to fail, but in a multicarrier C O F D M system, only a small percentage of subcarriers are interfered with, and these subchannels can also be corrected with error-correcting codes to ensure a low bit error rate of transmission.

 

5、Channel utilization is high.

This is especially important in wireless environments with limited spectrum resources, where the spectrum utilization of the system tends to be 2Baud/Hz when the number of subcarriers is large.