Microwaves
The micro in microwave, simply suggests that these waves are of a small or narrow magnitude. The length of theses waves can be measured in centimeters. One invention that has been with us for sometime now is the microwave oven; this is perhaps the first thing that springs to people's minds when microwaves are mentioned. Microwave ovens waves close to a foot in length, which is at the large scale in the spectrum of microwaves (N.D. Nasa.gov: Microwaves).
Microwaves are electromagnetic waves with wavelengths longer than those of infrared light, but shorter than those of radio waves (2006. Microwave From Wikipedia, the free encyclopedia).
Unlike most definitions, that use centimeters, we will use millimeters to describe wavelengths; this is just a personal preference.
Centimeters are used by dressmakers - in engineering we use either feet and inches or millimeters.
The last sentences was spouted out quite a few years ago in an introductory lecture in engineering, and for some reason it stuck; although now we should probably eliminate the feet and inches part! With that one out of the way here goes with some definitions:
| Wavelength | Frequency |
| 300mm | 1 GHZ |
| 1mm | 300 GHZ |
Table illustrating the range of microwaves (although this is debatable - see below)
Boundaries between far infrared light, microwaves, and ultra-high-frequency radio waves are fairly arbitrary and are used variously between different fields of study. The microwave range includes:
Above 300 GHz, the absorption of electromagnetic radiation by Earth's atmosphere is so great that it is effectively opaque , until the atmosphere becomes transparent again in the so-called infrared and optical window frequency ranges.
Microwave energy can penetrate haze, light rain and snow, clouds, and smoke making them an effective means of transmission.
Thus far we've described where microwaves fit in the spectrum of waves, and had a look at one application of microwaves. So what are the others?
Applications of microwave technology: