Basic concepts of microwave
When the electric charge or current system is constantly changing over time , the system generates the electric and magnetic field changes with time . Since the electric field changes the magnetic field around it stirred , AIDS field also changes in the electric field around it stirred , this change of the electric field and the magnetic field surrounding space to spread out the system . This movement of the electromagnetic field is called electromagnetic waves. Any electromagnetic oscillations radiated electromagnetic wave source systems are .
Electromagnetic fields are a form of energy , the propagation of electromagnetic waves must be accompanied by the energy transmission.
Microwave is an electromagnetic be . Radio communications technology continues to evolve and increase in capacity , in the radio communication waves with a wavelength shorter and shorter , and gradually by the long wave, medium wave, shortwave, FM waves to the microwave as well as development . Of course , usually including the wavelength range microwave no clear boundaries acres , generally refers to decimeter , centimeter and millimeter wave three bands. That is, wavelengths from about 1mm to about 1M of electromagnetic waves, visible , low-frequency end of the microwave band and general ultrashort high-frequency radio waves in the end ( wavelength of 1M. Frequency 300GLHz) adjacent to the high frequency end to the low-frequency and infrared side ( wavelength of 1mm, a frequency of 300GHz,; or wavelength of 0.1mM, a frequency of 300GHz) convergence. Because microwave frequency is high, it is sometimes also called microwave called UHF electromagnetic waves.
As the microwave wavelength and frequency ranges wide , resulting in a different range of its park has many unique properties , the use of these properties , the microwave in the different areas of application have been excellent . Which is the use of a microwave band to achieve special properties .
It is understood , has been used only pan- 915MHz and 2450M team two microwave frequencies. No two bands at higher power industrial equipment .
    Unlike ordinary microwave radio technology , in a small microwave systems , components, electrical properties can be considered to be lumped order , capacitive and inductive concept is no longer applicable , or even " current" , "Voltage " concept has lost its exact sense ; in the microwave field , usually used so-called " field " concept to analyze the structure of the electromagnetic wave within the system . And the use of power, frequency impedance , VSWR , etc., as the basic amount of microwave measurements .