The full form of CDMA is Code Division Multiple Access. This type of mobile phones already has a SIM card of same mobile company. For example – if you have a Reliance mobile, then only SIM of reliance will work in the mobile phone and rest of the other companies sim will not work. This means CDMA mobiles and SIMs should be of the same company, therefore today there are less CDMA mobile phones and GSM mobile users are increasing at a rapid pace.
CDMA is also known as a military technology, it was first used by the British against the Germans during the second World War. CDMA can be used to jam the transmission, by using it you can dismiss the signal.
Features Of CDMA Technology
- CDMA technology is used in the ultra-high-frequency cellular telephone system, where the band range is approximately 800MHz to 1.9GHz.
- CDMA technology is multiplexing, it enables multiple signals and can be used to capture a single transmission.
- The basic principle of CDMA is very different, CDMA codes are used to distinguish different users.
Usage Of CDMA Technology
- It is used in the Global Positioning System (GPS).
- It is used by several mobile phone companies (e.g. Qualcomm standard IS-2000 also known as CDMA2000)
- W-CDMA is used in UTMS 3G mobile phone standard.
- CDMA has been used in OmniTRACS satellite system for transportation.
Categories of CDMA
- Synchronous CDMA (orthogonal codes)
- Asynchronous CDMA (pseudorandom codes)