Architecture of Mobile Networks (2G, 3G and 4G)
1. Architecture of Mobile Networks:
The network architecture is divided into two main components:
1.1. RAN:
The Radio Access Network comprises the physical infrastructure deployed in the field to transmit and receive wireless signals, providing coverage and connectivity to mobile devices.
1.2. CN:
The core network is the central part of the network located in data centres, responsible for managing and routing traffic between radio sites and external networks such as the internet, handling control and managing various network services.
At the moment, MCCI is working on deploying 2G, 3G, 4G and 5G networks. These generations of mobile network technologies have evolved over time, each with its unique architecture and capabilities, enabling diverse communication services. The following is an overview of these generations and their architecture:
1.3. GSM Architecture:
The Global System for Mobile Communications, commonly known as 2G, was introduced in the early 1990s. It offered digital voice transmission and data services such as SMS, picture messages, and MMS. GSM uses a circuit-switched network architecture, dividing the radio spectrum into several channels, in IRAN, 2G operates at either the 900 MHz or 1800 MHz frequency bands.
The 2G network architecture comprises:
MS: Mobile Station, the mobile phone.
1.3.1. Radio Network:
The radio part in GSM is the BSS that includes the BTS known as RBS at Ericsson, which communicates with the MS, and the BSC that Regulate multiple cell sites, managing resources and setting up connections.
1.3.2. Core Network:
It includes the MSC, which is responsible for setting up and releasing end-to-end connections, handling registration of mobile users, routing calls, and managing location and handovers. It interfaces with other networks, such as PSTN.
The 2.5G offered internet access by connecting the BSC to the SGSN, GGSN to the IP network.
1.4. WCDMA Architecture:
Wideband Code Division Multiple Access, commonly known as 3G, was introduced in the early 2000s. It offered high-speed data transmission alongside digital voice services. WCDMA uses a packet-switched network architecture that enables faster data transfer rates and supports multimedia applications. In Iran, 3G operates on the 2100 MHz and 900 MHz frequency bands.
The 3G network architecture comprises:
UE: User Equipment, any device that accesses the internet via SIM card.
1.4.1. Radio Network:
The RNS, which consists of the NodeB that communicates with the UE, and the RNC that supervises radio resource management, handovers, and mobility management.
1.4.2. Core Network:
Contains the SGSN that provides the packet-switched capability and manages the routing of data packets, and the GGSN, which is a gateway situated between the SGSN and external data networks such as the internet.
The voice network remains the same as GSM.
1.5. LTE Architecture:
Long-Term Evolution, commonly known as 4G, was introduced in the late 2000s. It offered higher data speeds and lower latency. LTE uses an all-IP network architecture that enables faster data transfer rates and supports high-bandwidth applications such as video streaming, online gaming. In Iran, 4G operates on the 2100 MHz, 1800 MHz frequency bands for FDD and 2300 MHz for TDD.
The 4G network architecture comprises:
UE: User Equipment, any device that accesses the internet via SIM card
1.5.1. Radio Network:
Only includes the eNodeB, which communicates directly with UE.
1.5.2. Core Network:
The EPC comprises the SGW, which handles routing data packets to and from the UE, managing mobility and handovers between different sites, the PGW, which provides access to the internet, the MME that handles signalling between the UE and the network, and it is responsible for controlling the mobility and handover of the UE.