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The short wavelengths of microwaves allow omnidirectional antennas for portable devices to be made very small, from 1 to 20 centimeters long, so microwave frequencies are widely used for wireless devices such as cell phones, cordless phones, and wireless LANs (Wi-Fi) access for laptops, and Bluetooth earphones.
Wavelengths of electromagnetic radiation, whatever medium they are traveling through, are usually quoted in terms of the vacuum wavelength, although this is not always explicitly stated. Generally, electromagnetic radiation is classified by wavelength into radio wave, microwave, infrared, visible light, ultraviolet, X-rays and gamma rays. The ...
A microwave oven or simply microwave is an electric oven that heats and cooks food by exposing it to electromagnetic radiation in the microwave frequency range. [1] This induces polar molecules in the food to rotate and produce thermal energy in a process known as dielectric heating .
Microwave transmission is the transmission of information by electromagnetic waves with wavelengths in the microwave frequency range of 300 MHz to 300 GHz (1 m - 1 mm wavelength) of the electromagnetic spectrum.
Electromagnetic radiation phenomena with wavelengths ranging from one meter to one millimeter are called microwaves; with frequencies between 300 MHz (0.3 GHz) and 300 GHz. At radio and microwave frequencies, EMR interacts with matter largely as a bulk collection of charges which are spread out over large numbers of affected atoms.
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 [2] and for radar.
The absorption (equivalent to dielectric loss) is used in microwave ovens to heat food that contains water molecules. A frequency of 2.45 GHz, wavelength 122 mm, is commonly used. Radiocommunication at GHz frequencies is very difficult in fresh waters and even more so in salt waters. [11]
A microwave radiometer (MWR) is a radiometer that measures energy emitted at one millimeter-to-metre wavelengths (frequencies of 0.3–300 GHz) known as microwaves. Microwave radiometers are very sensitive receivers designed to measure thermally-emitted electromagnetic radiation. They are usually equipped with multiple receiving channels to ...