Cellular networks began as a way to make mobile calling practical by dividing a city into small coverage areas, or cells, each served by its own radio equipment. The idea of cellular switching dates to the early concept work in the 1940s and 1960s, but real progress accelerated in the late 20th century as radio technology and switching systems improved.
The first widely deployed systems were analog networks, enabling basic voice service but with limited capacity and security. In the 1990s, digital technologies took over, improving audio quality, efficiency, and supporting more advanced features. This shift also paved the way for data services.
Next came the major generations of mobile networks. 2G focused on digital voice and texting using Circuit switching; 2.5G enabled extended this by introducting packet switching for Internet access. 3G improved the packet switching which enabled faster mobile internet; 4G emphasized high speed broadband and more reliable streaming. More recently, 5G has moved toward even higher speeds, lower latency, and greater capacity, supporting not only phones but also connected devices and emerging use cases like smart infrastructure and industrial automation.
The 3GPP cellular standards use many abbreviations, some are listed here; for more, visit 3gpp.guru.
- RAT: Radio Access Technologies
- (2G) GSM: Global System for Mobile Communications
- (2.5G) GRPS: General Packet Radio Service + EDGE: Enhanced Data Rates for GSM Evolution
- (3G) UMTS: Universal Mobile Telecommunications System + HSDPA / HSUPA / HSPA+: High Speed (Downlink/Uplink/) Packet Access
- (4G) LTE: Long Term Evolution
- (5G) NR: New Radio
A cellular network is split into two main parts:
- the core network (CN) and
- the radio access network (RAN), where the RAN includes the base stations that provide wireless connectivity for the mobile/user equipment (ME/UE).
Subscriber and Device Identifiers:
- IMEI: International Mobile Equipment Identity
- IMEISV: IMEI + software version (of baseband)
- IMSI: International Mobile Subscriber Identity
- ICCID: Integrated Circuit Card Identifier
Network and Location Identifiers:
-
MCC: Mobile Country Code
-
MNC: Mobile Network Code
-
TAI: Tracking Area Identity
-
AS: Access Stratum (Um) (wireless interface)
-
NAS: Non-Access Stratum (non wireless interfaces)