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Both signal and noise in communication can be regarded as random processes that change with time. Random process has the characteristics of random variable and time function, which can be described from two different but closely related perspectives: (1) Random process i...

The communication mode refers to the working mode or signal transmission mode between the two communication parties. 1. Simplex, half-duplex, and full-duplex communication For point-to-point communication, according to the direction and time of message transmission, the ...

In a digital communication system, what the receiver receives is the sum of the transmitted signal and the channel noise. The optimal reception of digital signals is based on the minimum error probability as the "best" criterion. Errors considered in this chapter are mai...

Figure 6-6 is a block diagram of a typical digital baseband signal transmission system. It is mainly composed of sending filter (channel signal generator), channel, receiving filter and sampling decision. In order to ensure the reliable and orderly work of the system, th...

When the transmission capacity of a physical channel is higher than the demand for one signal, the channel can be shared by multiple signals, for example, the trunk line of a telephone system often has thousands of signals transmitted in a single fiber. Multiplexing is a technology to solve how t...

(1) AMI code AMI(Alternative Mark Inversion) code is the full name of alternate mark inversion code, its encoding rule is to alternately transform the message code “1″ (mark) to “+1″ and “-1″, while the “0″ (empty sign) remains unchanged. For exampl...