Microwaves and Infrared Radiation

Microwaves

• Frequency range: roughly 10^9 Hz (1 GHz) to 3 \times 10^{11} Hz.
• Wavelength range: approximately 30 cm to 1.0 mm.
• Wavelengths from less than 1 cm to about 30 cm can penetrate Earth's atmosphere.
• Key uses: Space-vehicle communications, radio astronomy, satellite communication (telephone/cell phone), airplane communication, television station communication.

Infrared Radiation

• Frequency range: merges with microwaves at around 300 GHz (1.0 mm wavelength) and extends to about 385 THz (780 mm wavelength).
• Nature: Heat radiation.
• Key uses: Television remote control units, motion detectors (security devices).