What does cofdm mean?
What does cofdm mean? COFDM (coded thogonal frequency division multiplexing), short for coding orthogonal frequency division multiplexing, is the most advanced and most promising modulation technology in the world.
Principle of cofdm
The basic principle of cofdm is to pass high-speed data streams through serial-to-parallel conversion and distribute them to several sub-channels with low transmission rate for transmission. Coding (C) means that the channel coding adopts a convolutional coding method with variable coding rate to adapt to the protection requirements of different importance data; orthogonal frequency division (OFD) refers to the use of a large number of carriers (subcarriers), which are equal. The frequency interval is an integer multiple of a basic oscillation frequency; multiplexing (M) means that multiple data sources are interleaved and distributed on the above plurality of carriers to form one channel.
Detailed introduction of cofdm technology
COFDM, short for encoding orthogonal frequency division multiplexing, is the most advanced and most promising modulation technology in the world. Its practical value lies in supporting the application of breakthrough line of sight limitation. It is a technology that is fully utilized in radio spectrum resources. It can have good immunity to noise and interference. Diffraction and penetration obstruction are COFDM technologies. core. The basic principle is that the high-speed data stream is transmitted through serial-to-parallel conversion and distributed to several sub-channels with a low transmission rate for transmission.
COFDM is a special multi-carrier communication scheme in which a single user's information stream is serial/parallel converted into multiple low-rate code streams, each of which is transmitted with one sub-carrier. Instead of bandpass filters to separate subcarriers, COFDM uses Fast Fourier Transform (FFT) to select waveforms that remain orthogonal even if aliased.
COFDM technology can simultaneously separate multiple digital signals and operate safely around the interfering signals. It is precisely because of this special signal "penetration ability" that COFDM technology is deeply loved and welcomed by communication equipment vendors. COFDM technology continuously monitors sudden changes in communication characteristics on the transmission medium. The ability of the communication path to transmit data changes over time. COFDM can dynamically adapt to it, and the corresponding carrier is switched on and off to ensure continuous operation. Successful communication. COFDM technology is particularly well-suited for use in high-rise buildings, densely populated and geographically prominent places, and areas where signals are broadcast, where high-speed data is transmitted.
Summary: From the above content, I know what cofdm means, and also understand the principle of cofdm and the corresponding technical features. For more information on security monitoring technology, please continue to pay attention to the hot security investment network.
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