Radio Bands What is GSM and CDMA?

[Guest awarner [MVP]]

What is GSM?

GSM (Global System for Mobile) communication is a European digital standard for mobile communication. This is the most widely used network standard worldwide.

The actual GSM bands are GSM 850, GSM 900, GSM 1800 and GSM 1900.

To make it look better, it started off being called GSM 800, GSM 900, GSM 1800 and GSM 1900 therefore GSM 800 and GSM 850 are the same thing (there is no GSM 800 in reality).

GSM 850 and GSM 1900 are used in the US.

GSM 900 and GSM 1800 are used everywhere else.

Tri band is either GSM 850/1800/1900 (US version) or GSM 900/1800/1900 (European version).

Quad band is GSM 850/900/1800/1900

[Guest awarner (MVP)]

What is CDMA?

CDMA (Code Division Multiple Access) is a military technology first used during World War II by English allies to foil German attempts at jamming transmissions. The allies decided to transmit over several frequencies, instead of one, making it difficult for the Germans to pick up the complete signal.

This enables multiple phone calls to be made at the same on the same frequency by using a voice-coding system.

The two main frequencies used with CDMA are 800, 1900 Mhz