Knowledge

The Best Reception of Digital Signals

In the digital communication system, the receiver receives sum of the transmitted signal and channel noise. The optimal reception of digital signals based on the “best” criterion with the smallest error probability. The errors considered in this chapter are mainly due to band-limited ... Read More

Composition of a Digital Baseband Signal Transmission System

Fig. 6-6 is a block diagram of a typical digital baseband signal transmission system. It is mainly composed of a transmission filter (channel signal generator), a channel, a reception filter, and a sampling decider. In order to ensure the reliable and orderly operation of the system, there should... Read More

Introduction to Digital Baseband Signal Waveforms

A digital baseband signal is an electrical waveform that represents digital information, which can be represented by different levels or pulses. There are many types of digital baseband signals (hereinafter referred to as baseband signals). Figure 6-1 shows a few basic baseband signal waveforms, ... Read More

Learning About The Signal

Acknowledgment signals can be divided into energy signals and power signals according to their strengths. Power signals can be divided into periodic signals and aperiodic signals according to whether they are periodic or not. The energy signal is finite in amplitude and duration, its energy is fi... Read More

Frequency Division Multiplexing

When the transmission capacity of a physical channel is higher than the demand of one signal, the channel can be shared by multiple signals. For example, the trunk line of a telephone system usually has thousands of signals transmitted on one optical fiber. Multiplexing is the technology that sol... Read More

Common Code Types for Baseband Transmission

1) The AMI code The full name of the AMI (Alternative Mark Inversion) code is the alternate mark inversion code. blank) remain unchanged. E.g: Message code: 0 1 1 0 0 0 0 0 0 0 1 1 0 0 1 1… AMI code: 0 -1 +1 0 0 0 0 0 0 0 -1 +1 0 0 -1 +1… The waveform corresponding to the AMI code is ... Read More