2013年1月4日星期五

UHF Radio Explained

Two Way UHF
UHF 2 way radio systems are used for short-range communications by businesses and public safety officials. Civilian two-way UHF applications include UHF citizen band radio and the popular 802.11b WiFi wireless computer networks. For longer range two-way systems, a repeater can help propagate the signal. Amateur radio operators (HAM’s) operate on several UHF bands as well.
Telephones
Cell phones and cordless telephones also use UHF frequencies carrying both analog and digital signals. The signals are limited to virtual line of sight, so they don’t travel so far that they interfere with each other. Cell tower repeaters help expand the range of cellular telephones without overloading the airwaves. Cell phones use a limited range in the UHF band from the 316 megahertz to 3.16 gigahertz portion of the UHF spectrum.
Global Positioning
Global positioning satellite systems use UHF wavelengths to help users navigate or find their way around town.
Commercial Application
Radio frequency identification (RFID) technologies use UHF and Ultra UHF frequencies to tag and track everything from shipping crates and store inventory to lions, tigers and bears.

没有评论:

发表评论