The kind of electric wave.
An electric wave is a kind of electromagnetic waves.Electromagnetic waves have many classifications.
Please also look at the frequency explained in another section.
| Frequency | Wavelength | Use |
| 〜300GHz | 0~1mm | X-rays, ultraviolet rays, infrared rays, etc. These are used for laser beams or the laser for processing. |
| 〜30GHz | 〜1cm | It is called a millimeter wave (EHF) and used for space communication. |
| 〜3GHz | 〜10cm | It is called microwave (SHF) and used for space communication or weather aviation. It is an electric wave used also for wireless electric supply. |
| 〜300MHz | 〜1m | It is the electric wave which is called ultrahigh frequency (UHF) and used for familiar portions, such as television and a mobile phone. Although the antenna installed in order to see ground digital broadcasting is called a UHF antenna, this is an antenna which receives UHF. |
| 〜30MHz | 〜10m | It is an electric wave which is called ultrashort waves (VHF) and used by television, an FM broadcast, etc. The VHF aerial which can receive VHF was used in the analog broadcasting of television. |
| 〜3MHz | 〜100m | It is called shortwave (HF) and used for the use of international telecommunications or others many. It is a standard frequency broadcast. |
| 〜300kHz | 〜1km | It is called a medium wave (MF) and used by a radio broadcast, traffic information, etc. |
| 〜30kHz | 〜10km | It is called a long wave (LF) and used for an airplane cruise. It is a standard frequency broadcast. |
| 30kHz〜 | 10km~ | They are a VLF wave (VLF) and the electromagnetic waves of a longer wavelength. |
Then,let`s study!
〜Hz
k, M, and G may follow this.We explain k, M, and G.
These are the same meanings as "MB" and "GB" seen in the unit of data.
1kHz(kilohertz)=1000Hz、1Hz×1000。
1MHz(megahertz)=1000kHz、1Hz×1000000。
1GHz(gigahertz)=1000MHz、1Hz×10000000000。
Example: 1 Hz vibrates once in 1 second.
1 kHz vibrates 1000 times in 1 second.
Wavelength.
wavelength is the distance which a wave follows in one cycle. Let's see a figure.
The portion of a red line is one wavelength.
The long wave shows that this wavelength also amounts to 10 km.
It is also the feature of electromagnetic waves that these length differs greatly, respectively.
図：excel
A atandard frequency broadcast
A standard frequency broadcast is a kind of a very high-precision electric wave.This unites the frequency of a radio-controlled clock or radio, and is used at the spot where an exact value is calculated.
a standard frequency broadcast is emitted in Japan
はがね山： http://goo.gl/maps/752Ju
おおたかど山： http://goo.gl/maps/bkckl
Microwave
It is also a certain electric wave that microwave is used for wireless electric supply.A wavelength is short and the feature which goes straight on is strong.
It is fit for emitting towards a specific direction.
It is used for weather radar and a marine radar.
Moreover, in a communicative field, since many information can be sent, it is used for wireless LAN, satellite broadcasting, etc., and the demand to next-generation electric wave use is high.
The difference in the feature of frequency or a wavelength is the feature of an electric wave.?? Please have a look.
【Reference】
総務省電波利用ページ
http://www.tele.soumu.go.jp/j/adm/freq/search/myuse /summary/
