Radio Access Network (RAN) is a key component in wireless communication systems that connects user equipment to the core network. Its main function is to transmit data and voice through wireless signals to achieve effective communication between users and the network.

Types of Radio Access Networks

There are many types of wireless networks, mainly GRAN, GERAN, UTRAN, E-UTRAN, and some other types, such as CRAN, VRAN, and ORAN.

GRAN: Global System for Mobile Communications (GSM) is one of the earliest technologies in RAN, originally used for the second generation 2G cellular network protocol.

GERAN: GSMEDGE radio access network standard uses enhanced data rate GSM evolution (EDGE) cellular technology, which helps improve data transmission and serves as a supplement to standard GSM.

UTRAN: The terrestrial radio access network of UMTS is responsible for connecting user equipment (UE) to the core network.

E-UTRAN: LTEUMTS radio access network is the next version of UTRAN, which can provide higher data transmission rates, lower communication latency, and is optimized for packet data.

CRAN: Centralized RAN is known as Cloud-RAN, which uses cloud computing as the core of its network and cellular signal data processing. 

VRAN: Virtualized RAN further leverages virtualization in CRAN to support the development of cellular technology, especially 5G networks.

ORAN: Open Radio Access Network (OpenRAN) is an architecture that strives to optimize the RAN through the decomposition of the elements of the RAN and the instantiation of software based on open source technologies and open standards.

How does a Radio Access Network work?

The basic structure of RAN includes base stations, wireless access equipment and user equipment. The base station is the core of RAN and is responsible for receiving and sending wireless signals. Modern RAN usually adopts a combination of macro base stations and small base stations. Macro base stations have wide coverage, while small base stations are used to supplement the signal quality of specific areas and improve user experience. The wireless access equipment is responsible for converting the signal of the base station into a data format that can be used by the user equipment.

During the working process, RAN first establishes a wireless connection with the user equipment. When the user turns on the mobile phone or other wireless device, it scans the available networks around and selects a base station with suitable signal strength to connect. The device sends an access request through the control channel. After receiving the request, the base station performs identity authentication to confirm the legitimacy of the user. Once the connection is successful, the user equipment can start data transmission with the network.

During the transmission, the base station sends the signal to the user equipment and receives the return signal from the user equipment. After the signal transmission is completed, RAN manages the mobility of the user equipment through wireless control technology. When the user equipment moves between different base stations, RAN will automatically switch to ensure that the user will not be interrupted during the call.

Finally, RAN also interacts with the core network through the network management system. The core network is responsible for processing user requests, including Internet access, voice services, etc., while RAN is responsible for transmitting these requests to user devices wirelessly.

‍Advantages of Radio Access Network

In today's era of rapid development of wireless communications, RAN (Radio Access Network) as a key component of wireless communication systems has become increasingly advantageous. The main function of RAN is to connect user devices to the core network through radio waves to provide users with efficient and stable wireless services. With the gradual advancement of 5G and future 6G technologies, the application advantages of RAN are to support higher data transmission speeds, achieve lower network latency, high flexibility and scalability.

RAN can provide a solid wireless communication foundation for different fields such as industrial automation, intelligent transportation, and distance education, and help digital empowerment and innovative development in all walks of life.