What technologies does communication engineering include?

Digital communication is the communication of transmitting digital signals, which means that the analog signals sent by the source are encoded into digital signals by the source of the digital terminal, and the digital signals sent by the terminal are encoded into digital signals suitable for channel transmission, and then the signals are modulated by the modem to the digital channels used by the system, and finally transmitted to the destination through inverse transformation. Digital communication has become the most important communication technology foundation in modern communication network because of its strong anti-interference ability and convenient storage, processing and exchange, and is widely used in various communication systems of modern communication network.

(2) Program-controlled switching technology

Program-controlled switching technology means that people use special computers to store pre-programmed programs in computers according to their own needs, and then complete various exchanges in communication. The PBX developed by program-controlled switching technology has the advantages of fast processing speed, small size, large capacity, strong flexibility and many service functions. It is convenient to change the functions of switches, build intelligent networks, provide users with more and more convenient telephone services, and realize the exchange of fax, data and image communication. It is controlled by program, and it is a kind of telephone exchange equipment that carries out physical exchange through time division multiplexing network. Common structures are centralized control, decentralized control or a combination of the two. There are many technical indicators, mainly BHCA/ call loss connection rate, time between failures and so on.

(3) Information transmission technology (computer transmission)

Mainly refers to a computer sending a fax to another remote computer or fax machine, a computer receiving a fax sent by a remote computer or fax machine, a screen conversation between two computers and file transmission between two computers, that is, EDI (Electronic Data Interchange) technology.

(D) Communication network technology

A communication network is a communication system in which communication endpoints, nodes and transmission links are organically connected with each other to provide connected or unconnected transmission between two or more designated communication endpoints. According to different functions and uses, communication networks can generally be divided into physical networks, business networks and support management networks.

(5) Data communication and data network

Data communication is a new communication method combining communication technology and computer technology. To transmit information between the two places, there must be a transmission channel. According to different transmission media, wired and wireless are distinguished, but they all connect data terminals with computers through transmission channels, so that data terminals in different places can share software, hardware and information resources.

(6) Broadband IP technology

The basic principle of IP over ATM is to encapsulate all IP packets into ATM cells at ATM layer and transmit them in the form of ATM cells in the channel. When a switch in the network receives an IP packet, it first processes the routing address according to the IP address of the IP packet through some mechanism and forwards it according to the route. Then, according to the calculated route, a virtual circuit (VC) is established on the ATM network, and future IP packets will be transmitted on this virtual circuit VC in a shortcut way, thus effectively solving the bottleneck problem of IP routers and improving the forwarding speed of IP packets to the switching speed.

(7) Access network and access technology

The access network can be defined by three interfaces, namely, the network side is connected with the service node through SNI, the user side is connected with the user through UNI, and the management side is connected with the telecom management network (TMN) through Q3 interface. Traditional Ethernet technology belongs to CPN instead of access network. Broadband access network based on Ethernet technology consists of local equipment and user equipment. The office is located in the community and the client is located in the residential building. This technology has powerful network management function and is compatible with traditional Ethernet at low cost.