Cellular frequencies

Cellular frequencies are the sets of frequency ranges within the ultra high frequency band that have been assigned for cellular phone use.[1] 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

Carrier UHF Voice Frequencies in MHz 3G UHF Frequency in MHz
Band name		 4G UHF Frequency in MHz
Band number		 3G
Technology		 4G
Technology
800 850 1700
2100		 1900 850 1700
2100		 1900 700 750 800 850 1700
2100		 1900 2500 GSM
HSPA+		 CDMA
EVDO		 WiMax LTE
CLR AWS PCS 12,17 13 26 5 4 2,25 41
AT&T Mobility Red X Green tick Red X Green tick Green tick Red X Green tick Green tick Red X Red X Green tick Green tick Green tick Red X Green tick Red X Red X Green tick
T-Mobile US Red X Red X Green tick Green tick Red X Green tick Green tick Green tick Red X Red X Red X Green tick Clock* Red X Green tick Red X Red X Green tick
Sprint Corporation Green tick Red X Red X Green tick Red X Red X Green tick Red X Red X Green tick Red X Red X Green tick Green tick Red X Green tick Green tick† Green tick§
Verizon Wireless Red X Green tick Red X Green tick Green tick Red X Green tick Red X Green tick Red X Red X Green tick Clock* Red X Red X Green tick Red X Green tick
U.S. Cellular Red X Green tick Red X Green tick Green tick Red X Green tick Green tick Red X Red X Green tick Red X Red X Red X Red X Green tick Red X Green tick
*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

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.

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.[4]

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

Detailed lists:

Other articles:

References

  1. ↑ G. Miao, J. Zander, K-W Sung, and B. Slimane, Fundamentals of Mobile Data Networks, Cambridge University Press, ISBN 1107143217, 2016.
  2. ↑ https://www.fcc.gov/encyclopedia/wireless-microphones
  3. ↑ http://www.fcc.gov/encyclopedia/broadband-personal-communications-service-pcs
  4. ↑ AWS References

External links

This article is issued from Wikipedia - version of the Tuesday, April 26, 2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.