There are many mobile or cell phone systems that are in use all over the world and there is a considerable amount of equipment ranging from the cell phones themselves to cellular base stations, antennas and the network infrastructure. In addition to the basic equipment there is new cell phone technology to provide the many new services that are now available, enabling cell phone users to enjoy many new applications from games, and ringtone downloads to picture and video downloads. With technologies ranging from GSM, GPRS, EDGE to UMTS or W-CDMA and cdmaOne (IS-95) to CDMA2000 1X, EV-DO and EV-DV and mobile TV technologies such as MediaFLO, DMB, and DVB-H, there are plenty of technologies in use.

The technology behind cellular systems and cell phones has developed from the first generation (1G) systems to the second geenration (2G) systems and then to the third generation (3G) systems. At each stage the performance improved and further facilities were available, from SMS messaging to video downloads.
- Major Mobile Phone Systems (a tabular overview)
- The Route from Analogue to 3G.

Cellular telecommunications basics.
There are a number of basic concepts behind cellular telecommunications systems. These include the idea of cells themselves as well as how the networks are set up, what is in a mobile phone and how some of the transmission technologies such as CDMA, TDMA and the like operate.
- The basic concept of a cellular telecommunications system
- The multiple access schemes used by mobile phones
- The duplex schemes used by mobile phone networks - FDD and TDD
- The operation and electronics within a mobile phone
- The basics of a cellular network
- The way in which a mobile phone registers onto a network
- Handover or handoff, the way in which cellular calls are transferred from one cell to another
- Code Division Multiple Access (CDMA) What it is and how it works
- Orthogonal Frequency Division Multiplex (OFDM) What it is and how it works

Each of the mobile or cell phone systems operates in a different way. Here are summaries of some of the major systems and technologies in use today.

Global System for Mobile Communications (GSM).
GSM is the system that was developed in Europe and is now the most popular system in use around the globe.
- The development of the Global System for Mobile communications - GSM
- GSM technical overview (5 pages)
- General Packet Radio Service, GPRS, tutorial (5 pages)
- Enhanced Data for GSM Evolution (EDGE)

CDMA System including cdmaOne (IS-95) and CDMA2000 (IS-2000)
The CDMA family of technologies including cdmaOne (IS-95) to CDMA 2000 were the first technologies to use CDMA technology.
- What is CDMA - cdmaOne / CDMA2000? A Guide to the CDMA system and its evolution.
- IS-95 (cdmaOne)
- CDMA2000 1xEV-DO
- CDMA Band Classes and Frequency Allocations

Universal Mobile Telecommunications System (UMTS) / Wideband CDMA (W-CDMA)
- UMTS / W-CDMA Tutorial (5 pages)
- High Speed Downlink Packet Access (HSDPA)
- High Speed Uplink Packet Access (HSUPA) The companion to HSDPA.
- UMTS TDD The scheme being used for mobile broadband.

Miscellaneous sytems and features
- Pacific or Personal Digital Cellular (PDC)
- i-mode for e-mails and internet surfing
- TD-SCDMA the 3G system being developed in China
Location services:
- Assisted GPS
Mobile video:
- Mobile video broadcasting video to phones using T-DMB and DVB-H
- DVB-H Digital Video Broadcasting - Handheld
- DMB Digital Multimedia Broadcasting

Private Mobile Radio PMR
Private or Professional Mobile Radio (PMR), or Public Access Mobile Radio (PAMR) is used in many countries around the world, and new technology is being developed to ensure it keeps up with today's needs. It is widely used by the emergency services, and this is particularly true of the new Tetra system that is being widely deployed.
An overview of private mobile radio (PMR) - the various standards that are available to use.
An overview of the basic "local" PMR system
Trunking using the MPT1327 system
An Overview of TETRA private mobile radio (PMR)