Encyclopedia of Wireless Networks

Living Edition
| Editors: Xuemin (Sherman) Shen, Xiaodong Lin, Kuan Zhang

Analog and Digital Communications

Living reference work entry
DOI: https://doi.org/10.1007/978-3-319-32903-1_82-1



The analog signal can be one of infinite number of values, while the digital signal can only be one of finite number of values. The analog signal transmission from one part to other parts is called analog communications, while the digital signal transmission from one part to other parts is called digital communications.

Historical Background

In practice, most signals that exist in the nature are analog signals, such as voice, image, video, temperature, pressure, and so on. There are infinite numbers of possible values for analog signal, which is continuous with time in most cases. According to the Nyquist theorem, the low-pass and band-pass analog signals can be converted into digital signals through sampling, quantization, and coding processes, which is known as analog-to-digital converting (ADC). During the ADC process, the error called quantization error is caused in the quantization process. After ADC process, the analog signal...

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Authors and Affiliations

  1. 1.Tongji UniversityShanghaiChina

Section editors and affiliations

  • Hsiao-hwa Chen

There are no affiliations available