Most wireless applications frequencies 1GHz > 30GHz are used
Microwaves closer to 15GHz - satellite TV eg. Foxtel 12.4GHz.
Mobile phones 1GHz > 2GHz
Bluetooth + current 802.11g WLANs 2.4GHz.
GPS 1GHz > 1.5GHz.
Infrared waves occur above microwaves and below visible light. For communication
systems, frequencies just above microwaves are used. Infrared waves travel in straight
lines hence a direct line of sight is required between source and destination. Currently
infrared is only used over short distances.
taken from Sam Davis' Information Processes and Technology – The HSC Course