Mobile telecommunication

The essentials

Mobile telecommunication lets people communicate while moving, using radio signals between mobile phones and nearby towers. Mobile technology has developed in generations, each adding speed and new services.

Key points

• 1G (first generation): analog technology used for voice calls only. Poor voice quality, low security and no data services.
• 2G: digital technology. Better voice quality and security; introduced text messages (SMS) and picture messages (MMS), and slow data. Standards such as GSM and CDMA.
• 3G: faster data, making mobile Internet, video calls and mobile TV practical.
• 4G: much higher speeds based fully on IP (Internet Protocol); supports high-definition video streaming, online gaming and video conferencing. LTE is a common 4G technology.
• 5G: very high speeds, very low latency (delay) and the ability to connect huge numbers of devices; supports the Internet of Things, smart cities and self-driving vehicles.
• Most phones can fall back to an older generation of network when a newer one is not available.
• The mobile network area is divided into small regions called cells, each served by a base station (tower); this is why mobile phones are called cellular phones.

Exam tips

• Remember the key jump in each generation: 1G analog voice, 2G digital and SMS, 3G mobile Internet and video calls, 4G all-IP high-speed broadband, 5G low latency and massive connectivity.

Common mistakes

• Saying SMS began with 1G; 1G was analog voice only.
• Treating 5G as only "faster 4G"; low latency and connecting many devices are equally important features.