What Network band is your smartphone on?
1. CELLULAR FREQUECIES
A key part of any mobile phone specification is its operating frequency bands. The supported frequency bands determine whether a certain handset is compatible with a certain network carrier.
The cellular frequencies are the sets of frequency which ranges within the ultra high frequency band that have been allocated for cellular phone use. All cellular phone networks worldwide use a portion of the radio frequency spectrum designated as ultra high frequency, or "UHF", for the transmission and reception of their signals. The ultra high frequency band is also shared with television, and Bluetooth transmission
The first widespread automatic mobile
network was in the 450 MHz band (NMT-450). As mobile phones became more popular and
affordable, mobile providers encountered a problem because they couldn't
provide service to the increasing number of customers. They had to develop
their existing networks and eventually introduce new standards, often based on
other frequencies. The GSM standard, which appeared to replace
NMT-450 and other standards, initially used the 900 MHz band too. As
demand grew, carriers acquired licenses in the 1,800 MHz band.
Some NMT-450 analog networks have
been replaced with digital networks using the same frequency; however, some carriers
received licenses for 450 MHz frequency to provide CDMA mobile coverage
area.
Many GSM phones
support three bands (900/1,800/1,900 MHz or 850/1,800/1,900 MHz) or
four bands (850/900/1,800/1,900 MHz), and are usually referred to as tri-band and quad-band phones, or world phones; with such a phone one
can travel internationally and use the same handset.
The actual frequency used by a
particular phone can vary from place to place, depending on the settings of the
carrier's base station.
Generally speaking, lower frequencies allow carriers to provide coverage over a larger area, while higher frequencies allow carriers to provide service to more customers in a smaller area.
2. GSM FREQUENCY BANDS
2G bands (850MHz to 1,900 MHz)
2G, first introduced in 1992, is the second-generation of cellular telephone technology and the first to use digital encryption of conversations. 2G networks were the first to offer data services and SMS text messaging, but their data transfer rates are lower than those of their successors.
Under 2G Bands there is GPRS and EDGE.
GPRS
General Packet Radio Service is a
packet-switching technology that enables data transfers through cellular
networks. It is used for mobile internet, MMS and other data communications. In
theory the speed limit of GPRS is 115 kbps, but in most networks it is around
35 kbps. Informally, GPRS is also called 2.5G.
EDGE
Enhanced Data for Global Evolution (also known as Enhanced GPRS or EGPRS) is a data system used on top of GSM
networks. It provides nearly three times faster speeds than the outdated GPRS
system. The theoretical maximum speed is 473 kbps for 8 timeslots but it is
typically limited to 135 kbps in order to conserve spectrum resources. Both
phone and network must support EDGE, otherwise the phone will revert
automatically to GPRS.
EDGE
meets the requirements for a 3G network but is usually classified as 2.75G.
3G Bands (850MHz to 2,100 MHz)
3G networks succeeded 2G ones, offering faster data transfer rates and are the first to enable video calls. This makes them especially suitable for use in modern smartphones, which require constant high-speed internet connection for many of their applications.
3G is
loosely defined, but generally includes high data speeds, always-on data
access, and greater voice capacity.
The
high data speeds are possibly the most prominent feature, and certainly the
most hyped. They enable such advanced features as live streaming video.
There
are several different 3G technology standards. The most prevalent is UMTS,
which is based on WCDMA (the terms WCDMA and UMTS are often used
interchangeably).
UMTS
Universal Mobile Telecommunications System (UMTS) is a third generation
wireless network technology which allows speeds of up to 2Mbps.
UMTS
is based on the WCDMA technology, which is why these terms have become
interchangeable.
WCDMA
Wideband Code Division Multiple Access (WCDMA) is a third-generation (3G) wireless standard which allows the use of both
voice and data and offers data speeds of up to 384 Kbps.
WCDMA
is also called UMTS and the two terms have become interchangeable.
Some
parts of the WCDMA are based on GSM technology and the networks are designed to
integrate the GSM networks at some levels.
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