Introduction to Hertz Gigahertz and Megahertz
Hertz is a measurement of the transmission frequency of radio signals in a second. Named after the scientist Hein rich hertz, a single MHz (megahertz) is equivalent to a million cycles/sec.
A single GHz (gigahertz) is equivalent to a thousand MHz (which would be one billion cycles).
The range for most wireless networks fall in the radio frequency of 2.4-5 GHz. WiMax is capable of a much greater range, but networks like WiMax hence need more power to function well as the larger a frequency range gets (for instance 5 or higher GHz) it needs more and more power to overcome the effects of barriers and other interferences.