Definition
A unit of frequency equal to one billion (1,000,000,000) cycles per second. Used to measure the frequency of radio waves, microwaves, and electronic signals operating in very high frequency ranges.
Plain English
A way of measuring how fast a wave or signal repeats — one gigahertz means the signal completes a billion full cycles every second.
Context Anchor
Seen in aircraft electronics, antenna, radar, and communication system information where signal frequency is listed.
Derivation
‘Giga-’ comes from the Greek ‘gigas,’ meaning ‘giant,’ and is used in the metric system to mean one billion. ‘Hertz’ is named after Heinrich Hertz, the German physicist who first proved the existence of radio waves. So gigahertz literally means ‘a billion hertz’ — a billion cycles per second.
Why Pilots Care
Many systems pilots and technicians work with — GPS, radar altimeters, weather radar, satellite communications — operate in the gigahertz range. Knowing the frequency band helps when troubleshooting interference, antenna issues, or system specifications.
Intuition Check
GHz is a measure of how often a signal repeats, not how strong the signal is or how far it will travel.
Example Sentence 1
GPS satellites transmit navigation signals to aircraft receivers at frequencies near 1.5 GHz.
Example Sentence 2
The technician checked the GPS unit output in GHz during the preflight inspection.