• Cell phone RF specifications are determined by the International Telecommunications Union.cell phone image by Alexey Klementiev from Fotolia.com
  
  Cell phone radio frequency, or RF, specifications are set forth by the International Telecommunications Union, or ITU, which designates what portion of the RF spectrum is to be used by a particular type of wireless data transmission technology. Most modern cell phones use the Global System for Mobile Communications, or GSM, or Personal Communications Service, or PCS, technologies for data transmission. GSM is the most common standard for mobile phones and is further specified by the ITU as GSM-850, GSM-900, GSM-1800 and GSM-1900, based on the radio frequencies allocated for use.
  
  

PCS

• Cell phone RF specifications for phones using PCS technology indicate that data transmission must use the 1900MHz radio band frequency. PCS RF transmission at the 1900MHz frequency is commonly used in Canada, the United States and Mexico. PCS is primarily a 2G network technology, whereas GSM technology can be used on 2G, 3G or 4G wireless networks.
  
  

GSM-850

• Cell phones utilizing GSM-850 technology use the RF band from 824MHz to 849MHz for data transmission. GSM-850 cell phone networks are used in Canada, the United States and many countries in South and Central America.
  
  

GSM-900

• Cell phones that use GSM-900 technology must transmit on channels located in the 890MHz to 915MHz RF band. GSM-900 cell phone transmission is used in Australia, Africa, the Middle East, Europe, El Salvador, Guatemala and Brazil.
  
  

GSM-1800

• GSM-1800 cell phone networks utilize one frequency range to transmit data from the cell phone and another frequency range when receiving data on the phone. GSM-1800 transmits from a cell phone to the base transceiver station, or cell phone tower, using the 1710MHz to 1785MHz RF band and receives data from the cell phone tower using the 1805MHz to 1880MHz range of the RF spectrum. GSM-1800 technology is used in Africa, Australia, Europe, the Middle East and most of Asia.
  
  

GSM-1900

• GSM-1900 networks also use one frequency range to transmit data from the cell phone to the base transceiver station and a second frequency range to receive data on the cell phone. GSM-1900 transmits data from the cell phone to the network using the RF range of 1850MHz to 1910MHz. Data is transmitted to and received by the cell phone using the RF spectrum from 1930MHz to 1990MHz. GSM-1900 cell phone networks are used the United States, Canada, Mexico, South America and Central America. GSM-1900 can operate and coexist with PCS network data transmission that also occurs at 1900MHz.