Cellular frequencies

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Cellular frequencies are the sets of frequency ranges within the ultra high frequency band that have been assignet for cellular phone use. Most cellular phone networks worldwide use portions of the radio frequency spectrum, allocated to the Mobile service, for the transmission and reception of their signals. The particular bands may also be shared with other radiocommunication services, e.g. Broadcasting service, and Fixed service operation.

Radio frequencies used for cellular networks differ in ITU Regions (Americas, Europe, Africa and Asia). The first commercial standard for mobile connection in the United States was AMPS, which was in the 800 MHz frequency band. In Nordic countries of Europe, the first widespread automatic mobile network was based on the NMT-450 standard, which was in the 450 MHz band. 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. Some European countries (and Japan) adopted TACS operating in 900 MHz. The GSM standard, which appeared in Europe 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. (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.)

In the U.S., the analog AMPS standard that used the cellular band (800 MHz) was replaced by a number of digital systems. Initially, systems based upon the AMPS mobile phone model were popular, including IS-95 (often known as "CDMA", the air interface technology it uses) and IS-136 (often known as D-AMPS, Digital AMPS, or "TDMA", the air interface technology it uses). Eventually, IS-136 on these frequencies was replaced by most operators with GSM. GSM had already been running for some time on US PCS (1,900 MHz) frequencies.

And, some NMT-450 analog networks have been replaced with digital networks using the same frequency. In Russia and some other countries, local 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. This portability is not as extensive with IS-95 phones, however, as IS-95 networks do not exist in most of Europe.

Mobile networks based on different standards may use the same frequency range; for example, AMPS, D-AMPS, N-AMPS and IS-95 all use the 800 MHz frequency band. Moreover, one can find both AMPS and IS-95 networks in use on the same frequency in the same area that do not interfere with each other. This is achieved by the use of different channels to carry data. The actual frequency used by a particular phone can vary from place to place, depending on the settings of the carrier's base station.

United States Carrier Frequency Use[edit]

Carrier UHF Voice Frequencies in MHz 3G UHF Frequency in MHz
Band name
4G UHF Frequency in MHz
Band number
800 850 1700
1900 850 1700
1900 700 750 800 850 1700
1900 2500 GSM
CLR AWS PCS 12,17 13 26 5 4 2,25 41
AT&T Mobility Red XN Green tickY Red XN Green tickY Green tickY Red XN Green tickY Green tickY Red XN Red XN Green tickY Green tickY Green tickY Red XN Green tickY Red XN Red XN Green tickY
T-Mobile US Red XN Red XN Green tickY Green tickY Red XN Green tickY Green tickY Green tickY Red XN Red XN Red XN Green tickY ClockC* Red XN Green tickY Red XN Red XN Green tickY
Sprint Corporation Green tickY Red XN Red XN Green tickY Red XN Red XN Green tickY Red XN Red XN Green tickY Red XN Red XN Green tickY Green tickY Red XN Green tickY Green tickY Green tickY§
Verizon Wireless Red XN Green tickY Red XN Green tickY Green tickY Red XN Green tickY Red XN Green tickY Red XN Red XN Green tickY ClockC* Red XN Red XN Green tickY Red XN Green tickY
U.S. Cellular Red XN Green tickY Red XN Green tickY Green tickY Red XN Green tickY Green tickY Red XN Red XN Green tickY Red XN Red XN Red XN Red XN Green tickY Red XN Green tickY
*Promised/in construction.
2010 - Current.
§ 2012 - Current.
Current / Planned Technologies Previous Technologies Band UHF Frequency (MHz)
3G, 4G, MediaFLO (defunct), DVB-H UHF TV 52-69 (698-806 MHz)* 700 698–806
SMR iDEN, ESMR CDMA (future), ESMR LTE (future) UHF TV 70-83 (806-890 MHz) 800 806–824 and 851–869
GSM, IS-95 (CDMA), 3G AMPS, IS-136 (D-AMPS) 850 824–849 and 869–894
Unknown 1400 1,392–1,395 and 1,432–1,435
GSM, IS-95 (CDMA), 3G, 4G IS-136 (D-AMPS) PCS 1,850–1,910 and 1,930–1,990
3G, 4G AWS 1,710–1,755 and 2,110–2,155
4G BRS/EBS 2,496–2,690
  • Professional wireless microphones used the 700 MHz band until 2010 when they were made illegal, but equipment still exists in use that may interfere with 3G and 4G technologies. [1]

The usage of frequencies within the United States is regulated by the Federal Communications Commission (FCC). The US is then divided geographically into a number of Trading Areas. A mobile operator (or other interested parties) must bid on each trading area individually. A bidder can use the frequency spectrum for whatever purpose they want.

The 869–894 MHz cellular band is divided into 2 frequency blocks (A and B). There are 306 Metropolitan Service Areas and 428 rural service areas. Each trading area consists of one or more counties.

The 1850–1990 MHz PCS band is divided into six frequency blocks (A through F). Each block is between 10 MHz and 30 MHz in bandwidth. License (A or B) is granted for Major Trading Areas (MTAs). License (C to F) is granted for Basic Trading Areas (BTAs). License (G), where issued, is granted for Economic Areas (EAs). There are 51 MTAs, 493 BTAs and 175 EAs in the United States.

  • A: 1850–1865 MHz and 1930–1945 MHz (30 MHz)
  • B: 1870–1885 MHz and 1950–1965 MHz (30 MHz)
  • C: 1895–1910 MHz and 1975–1990 MHz (30 MHz, 15 MHz or 10 MHz)
  • D: 1865–1870 MHz and 1945–1950 MHz (10 MHz)
  • E: 1885–1890 MHz and 1965–1970 MHz
  • F: 1890–1895 MHz and 1970–1975 MHz
  • G: 1910–1915 MHz and 1990–1995 MHz[2]

The Advanced Wireless Services (AWS) bands, auctioned in the summer of 2006, were for 1,710–1,755 MHz, and 2,110–2,155 MHz. The spectrum was divided into blocks: A blocks were for Cellular Market Areas, based on existing cellular (1G) licenses, and were 2 × 10 MHz. B and C blocks (2 × 10 MHz and 2 × 5 MHz respectively) were for Basic Economic Areas, larger than CMAs, usually comprising large portions of single states. D, E, and F blocks covered huge areas of the country, typically several states at a time, and covered 2 × 5 MHz for D and E blocks, 2 × 10 MHz for F.[3]

The 700 MHz band was auctioned in early 2008 using spectrum previously used by television stations' analog broadcasts, with Verizon Wireless and AT&T Mobility winning the majority of available spectrum. Qualcomm and Echostar were winners of a significant amount of broadcast-oriented spectrum. Verizon Wireless will use the upper band of the 700 MHz spectrum to deploy their LTE network starting on Dec 5, 2010.

The SMR 800 MHz band was used exclusively for iDEN technology, however, Sprint Corporation is deploying CDMA and LTE technology on this band. As of 2 September 2011, the FCC has approved several CDMA devices for use on the SMR band.

More bands are under consideration for auction by the FCC. These are currently used by DoD, NASA, and other government agencies.

Cellular and PCS bands are also used in other countries in the Americas.

See also[edit]

Detailed lists:

Other articles:


External links[edit]