CDMA and GSM are common words which anybody would have heard . Both are wireless technology standards , used in radio communications. CDMA and GSM both are multiple access technologies .
| CDMA(Code Division Multiple Access) | GSM(Global System for Mobile Communications ) |
|---|---|
| CDMA is an example of multiple access, where several transmitters can send information simultaneously over a single communication channel. This allows several users to share a band of frequencies . | GSM is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe protocols for second-generation (2G) digital cellular networks |
| Practically CDMA is a handset based standard . For CDMA , a CDMA handset is required . The phone number is bound to the handset. | In GSM , only SIM is bound to phone number . |
| Each CDMA phone has a specific code which identifies it . One CDMA network covers all CDMA devices within it's range . | In case of GSM , each SIM is served by a network tower in which the sim is currently present . As location changes , Network tower also changes . |
| In CDMA customer information is put in a phone . | In GSM customer information is put on a sim card. |
| In CDMA , each call-signal is encoded with a unique key and all the calls are transmitted at once .The combined signal is divided into corresponding individual calls at the receivers end using the unique key . | In GSM calls are converted into digital data and assigned a time slot on the signal . A buzzing sound is sometimes produced due to this pulsing division of the signal . |
| Frequency 850MHz | Frequency 850 MHz - 1900 MHz . |
| It consumes less power . | It consumes more power . |
| It has a market share of approx 80 % | It has a market share of approx 20%. |