1. Meaning
In electronics, a multiplexer (multiplexer or mux) can select a signal from multiple analog or digital input signals and forward it, and output different selected signals to the same output line.
Multiplexing technology may follow one of the following principles, such as: TDM, FDM, CDM or WDM. Multiplexing technology is also applied to software operations, such as: simultaneous transmission of multi-threaded information streams to equipment or programs.
2. Meaning
The purpose of using a multiplexer is to make full use of the capacity of the communication channel and greatly reduce the cost of the system. For example, for a pair of telephone lines, its communication frequency band is generally above 100kHz, and the frequency band of each telephone signal is generally limited to below 4kHz. At this time, the capacity of the channel is far greater than the information transmission volume of a phone.
Using multiplexers, multiple channels of data information can share one channel. When the data stream on the multiplexed line is continuous, this sharing method can achieve good results. Obviously, this is more economical than using a communication line for each terminal. Multiplexers are always used in pairs. One continuous terminal, the other near the host, its function is to separate the received composite data stream according to the channel, and send them to the corresponding output line, so it is called a demultiplexer.