What are TRI-BAND technologies?

Many mobile phones use TRI-BAND technology, allowing them to communicate on multiple cell frequency belts. This allows them to use multiple frequencies if the waves are too busy and allow them to work in other parts of the world where different frequencies are used. TRI-BAND technology is generally used with the standard of the global mobile communication system (GSM), which uses AT&T and T-Mobile in the US. The GSM850, GSM900, GSM1800 and GSM1900 concern the approximate frequency of the Megahertz band (MHz), although the actual communication occurs at both ends of the above frequency. For example, the GSM850 includes a number of channels for both recording and downloading and in fact expanding 824.2 to 894.2 MHz. While the GSM1900 is predominant in most of the United States, regularly is also used, especially in remote areas. Other countries usually use the GSM900, which was the original GSM group, and have since expanded to the GSM1800. Many countries also use SteFrequency as the United States.

TRI-BAND telephone is able to communicate on three of the four GSM strips. Some TRI-MODE phones that are designed for the US work both on the GSM850 and GSM1900 bands, as well as support GSM1800 for international travel. A world traveler should look for a triple phone supporting GSM900, GSM1800 and GSM1900, which trade with some US abilities exchange for better international roaming coverage. The four -band phone will support each GSM group, eliminating the compromise between the US and the global performance that is necessary when selecting a three -band phone.

In addition to three-band phones, many manufacturers also produce three-red phones. These phones can only work in GSM, but also on multiple access networks (CDMA) such as Verizon and Sprint's power in the US, and on an analog advanced mobile systemphones (AMP). While some Tri-mode phones support GSM, CDMA and AMPS, others only support two network systems with double band support for one of them. These phones are technically dual mode, dual zone set. International travelers can be well served with one of these phones that support both the double GSM bands and amplifiers for countries with older mobile networks.