Super high frequency
Super high frequency (SHF) is the ITU designation for radio frequencies (RF) in the range between 3 and 30 gigahertz (GHz). This band of frequencies is also known as the centimetre band or centimetre wave as the wavelengths range from one to ten centimetres. These frequencies fall within the microwave band, so radio waves with these frequencies are called microwaves. The small wavelength of microwaves allows them to be directed in narrow beams by aperture antennas such as parabolic dishes and horn antennas, so they are used for point-to-point communication and data links[1] and for radar. This frequency range is used for most radar transmitters, wireless LANs, satellite communication, microwave radio relay links, satellite phones (S band), and numerous short range terrestrial data links. They are also used for heating in industrial microwave heating, medical diathermy, microwave hyperthermy to treat cancer, and to cook food in microwave ovens.
$_$_$DEEZ_NUTS#0__titleDEEZ_NUTS$_$_$
$_$_$DEEZ_NUTS#0__subtitleDEEZ_NUTS$_$_$
$_$_$DEEZ_NUTS#0__call_to_action.textDEEZ_NUTS$_$_$Advantages[edit]
SHF frequencies occupy a "sweet spot" in the radio spectrum which is currently being exploited by many new radio services.[3] They are the lowest frequency band where radio waves can be directed in narrow beams by conveniently sized antennas so they do not interfere with nearby transmitters on the same frequency, allowing frequency reuse. On the other hand, they are the highest frequencies which can be used for long distance terrestrial communication; higher frequencies in the EHF (millimeter wave) band are highly absorbed by the atmosphere, limiting practical propagation distances to one kilometer or less. The high frequency gives microwave communication links a very large information-carrying capacity (bandwidth). In recent decades many new solid state sources of microwave energy have been developed, and microwave integrated circuits for the first time allow significant signal processing to be done at these frequencies. Sources of EHF energy are much more limited and in an earlier state of development.
$_$_$DEEZ_NUTS#1__titleDEEZ_NUTS$_$_$
$_$_$DEEZ_NUTS#1__descriptionDEEZ_NUTS$_$_$
$_$_$DEEZ_NUTS#2__titleDEEZ_NUTS$_$_$
$_$_$DEEZ_NUTS#2__subtextDEEZ_NUTS$_$_$
$_$_$DEEZ_NUTS#3__titleDEEZ_NUTS$_$_$
$_$_$DEEZ_NUTS#3__subtextDEEZ_NUTS$_$_$