In the US, AT&T as well as T-Mobile phones use GSM – and most of the rest of the world uses GSM as well. CDMA in the US is Verizon, Sprint and US Cellular. You need to read up on the subject.
Read moreWhat US GSM phone?
The Global System for Mobile Communications (GSM) is a standard developed by the European Telecommunications Standards Institute (ETSI) to describe the protocols for second-generation (2G) digital cellular networks used by mobile devices such as mobile phones and tablets.
Read moreDoes the US use CDMA or GSM?
Of the two, GSM is more widely used around the globe, with availability in more than 200 countries. While CDMA is used widely in the U.S. , it is less common elsewhere — most estimates pin the portion of global wireless networks using CDMA at less than 20 percent. The Verizon network is a CDMA wireless network.
Read moreWhy CDMA Cannot be used for higher bit rates?
CDMA has a soft capacity. The greater the number of codes, the more number of users. However, many codes are used S/I drops and the BER (Bit Error Rate) will increase for all users. CDMA requires a tight power control as it suffers from near-far effect .
Read moreWhat is CDMA bandwidth?
The CDMA channel is nominally 1.23 MHz wide. CDMA networks use a scheme called soft handoff, which minimizes signal breakup as a handset passes from one cell to another. The combination of digital and spread spectrum modes supports several times as many signals per unit of bandwidth as analog modes.
Read moreWhat is CDMA capacity?
CDMA allows up to 61 concurrent users in a 1.2288 MHz channel by processing each voice packet with two PN codes.
Read moreWhy a given bandwidth is used most efficiently in CDMA?
CDMA technology claims that its bandwidth is thirteen times efficient than TDMA and forty times efficient than analog systems. CDMA also have better security and higher data and voice transmission quality because of the spread spectrum technology it uses, which has increased resistance to multipath distortion .
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