GSM technology works in the frequncy bands of 900 and 1800MHz in india and CDMA technology works in the frequncy band of 800MHz.no it is based on non line of sight communication(NLOS).
Posted: 03-07-2011 @ 23:02:50
Data rate - 144 Kbit/sec
Connection of up to 2000 subscribers to the system.
Connection of 6 tо 32 subscriber stations
Maximum communication range - 30 km.
GSM standard - 900/1800
Interfaces - RS-232, USB
Maximum number of subscribers to be served from one terminal - 4/8
Measurements - 40x225x165 mm
Posted: 03-07-2011 @ 14:22:55
Most phone networks across the world use a mix of four frequencies; 850 MHz, 900 MHz, 1800 MHz and 1900 MHz.
Access will be determined by the phone capability i.e. 3G, dual band, tri band or quad band.
dual band phones can use 900 MHz and 1800 MHz frequencies and work in most European countries
tri band phones are able to use 900 MHz, 1800 MHz and 1900 MHz and work on most European networks, as well as some networks in the USA, Canada, the Caribbean and South America
quad band phones are able to connect to all four frequencies – 850 MHz, 900 MHz, 1800 MHz, and 1900 MHz
3G handsets work in all countries where 2G roaming is currently available.
In addition to GSM bandwidths 3G handsets also use W-CDMA 2100 (Wideband Code Division Multiple Access) to provide the 3G features, such as video telephony, increased data speeds etc. This appears to give the handset an extra 'bandwidth' but it does not change a tri band handset to quad band, dual band to tri band etc.
An example of this is the Nokia 6630 handset, as it works on the GSM 900 / 1800 / 1900 bandwidths but also works on WCDMA 2100.
Although it has four bands it is classed as a tri band handset in terms of roaming.
Posted: 01-07-2011 @ 16:10:45