The relationship between wavelength and frequency is that they are inversely proportional, wave velocity = wavelength × Therefore, electromagnetic waves with different frequencies have different wavelengths in the air. the propagation speed of electromagnetic waves with different frequencies (or different wavelengths) is the same. the propagation speed in the air is about 3x10e8 m/s. the higher the frequency of electromagnetic waves, the shorter the corresponding wavelength. the electromagnetic wave having a larger frequency has a shorter wavelength. radio waves have the longest wavelength (lowest frequency), while rays have the shortest wavelength (highest frequency)
Generally, radio waves refer to the peak 30GHz (Giga Hertz) from the extremely low frequency 10KHz to the extremely high frequency. because the radio spectrum beyond this range has very different characteristics, such as light and X-rays. however, the above-mentioned 10KHz to 30GHz is usually divided into seven areas, of which the high frequency 3-30MHz is what we usually call short wave
VLF, Very Low Frequency, 10KHz - 30KHz
LF, Low Frequency, 30KHz - 300KHz
MF, Medium Frequency, 30KHz - 3000KHz
HF or SW, High Frequency, 3MHz - 30MHz
VHF, Very High Frequency, 30MHz - 300MHz
UHF, Ultra High Frequency, 300MHz - 3000MHz
SHF, Super High Frequency, 3GHz – 30GHz |