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List of contents of this article:

• 1,What is gsm?
• 2 、 What is a digital communication system and what are its types?

What is gsm?

Global Mobile Communications System, abbreviated as GSM, is a digital mobile communication standard formulated by ETSI, the European Telecommunication Standards Organization. Its air interface adopts time-time multi-address technology. Since it was put into commercial use in the mid-1990s, it has been adopted by more than 100 countries around the world.

gsm refers to the global mobile communication system. The Global Mobile Communication System, abbreviated as GSM, is a digital mobile communication standard formulated by ETSI, the European Telecommunications Standards Organization. Its air interface adopts time-time multi-address technology. Since it was put into commercial use in the mid-1990s, it has been adopted by more than 100 countries around the world.

Global System for Mobile CommunIcation is the well-known GSM, which is currently the most widely used mobile phone standard. More than 1 billion people in more than 200 countries and regions around the world are using GSM phones.

GSM's full name is Global System for Mobile Communications, which is a global mobile communication system in Chinese and a digital mobile phone network standard developed by Europe.

What is a communication system?

The communication system is roughly composed of three parts: the sender (send and sending device), the channel receiving device (the message and receiving device), and the noise source. The source is the source of information, and its function is to convert the original signal into the corresponding electrical signal, that is, the baseband signal.

Communication system A communication system or communication system is a separate collection of telecommunications networks, transmission systems, relay stations, tributaries and terminal equipment, which can usually be connected and operated with each other to form a whole.

Communication system refers to a system that uses electrical signals (or optical signals) to transmit information, also known as a telecommunications system.A system is usually an organic whole composed of several units with specific functions, interactions and interdependence to achieve a unified goal. The simplest communication system is for two-point users to send and receive information to each other.

Communication systems work in noisy environments. When designing an analog communication system, the minimum mean square error criterion is adopted, that is, the signal-to-noise ratio output by the receiver is the largest.

The communication system is developing in the direction of comprehensive anti-destruction, that is, to realize a confidential communication system that can resist interference, nuclear attack and electromagnetic pulses.

What is a digital communication system and what are its types?

1. Digital communication uses digital signals as a carrier to transmit messages, orThe communication method of digitally modulating and then transmitting carrier waves with digital signals can transmit digital signals such as telegrams and digital data, as well as analog signals such as digitally processed voice and images.

2. Digital communication systems can be further subdivided into digital frequency band transmission communication system, digital baseband transmission communication system, and analog signal digital transmission communication system. The basic feature of digital communication is that its messages or signals have "discrete" or "digital" characteristics, so that digital communication has many special problems.

3. The purpose of the basic model communication of the communication system is to deliver messages. Messages include symbols, text, speech, music, pictures, data, images and other forms. Basic point-to-point communication is to pass messages from the sender to the receiver through a certain channel.The basic model description of the communication system is shown in Figure 1.