What Is a Wireless Modem?
A modem is a word coined from the initial letters of modulator and demodulator and generally refers to a device that mutually converts analog signals on coaxial cables or telephone lines into digital signals for computers and smartphones.
A wireless modem is a device that uses wireless communication as the transmission path for the modem’s line, instead of wired lines such as optical or telephone lines.
Wireless modems have become popular in recent years because people who move frequently do not need to re-contract their Internet connection with each move.
Uses of Wireless Modems
Business people often use wireless modems to connect to their computers and access the Internet on business trips or at home. Among the most popular general-purpose wireless modems are recent small USB-type modems that can be connected to a PC and then used to wirelessly connect to broadband Internet with a base station.
Currently, Wi-Fi communication is the most common, as well as 4G (LTE), 5G, and other mobile terminal communication standards.
Principle of Wireless Modem
The operating principles of modulation and demodulation, which are the main roles of a modem, are explained below:
Modulation refers to the conversion of a digital signal into an analog signal. Specifically, this is the operation of putting digital information onto an analog signal by placing signal amplitude and phase information on a carrier wave (carrier).
Demodulation, conversely, is the process of extracting the desired digital information from the carrier.
The types of wireless communication used for carriers include 3G (WCDMA) and 4G (LTE), which are the communication standards for mobile terminals, and 5G, which is now becoming the mainstream communication standard.
Wi-Fi operates on carrier frequencies in the 2.4GHz and 5GHz bands, which are the main communication standards for wireless LAN. Although the 5GHz band offers the most stable communication, it is usually shared with the 2.4GHz band (which can fly farther due to its shorter range and susceptibility to obstacles).
There are also packet communications, specific amateur radio communications, and other low-power radios such as the ISM band (2.4GHz).