Megahertz (Mega Hertz, MHz) is one of the fluctuation frequency units. The basic unit of the fluctuating frequency is Hertz, which is adopted in the thousands system; 1 MHz is equivalent to 1000 kHz (KHz), which is 10^6 Hz. It is worth noting that megahertz is just a definitional noun, with 1 million solutions in units of measurement.
In the radio frequency allocation defined by the International Telecommunication Union:
Very low frequency (ULF): 3~30 kilohertz (KHz)
Low frequency (LF): 30~300 kilohertz (KHz)
Intermediate frequency (MF): 300~3000 kilohertz (KHz)
High frequency (HF): 3~30 megahertz (MHz)
Very high frequency (VHF): 30~300 megahertz (MHz)
Ultra High Frequency (UHF): 300~3000 MHz
Ultra High Frequency (SHF): 3~30 Hz
Extremely high frequency (EHF): 30~300 Hz (GHz)
Electricity (voltage or current) is divided into DC and AC. In communication applications, AC is generally used for signal transmission. The alternating current signal that changes sinusoidally changes with time, and its amplitude is positive and negative when it propagates forward with a certain energy and speed.
In general, we call the number of repeated changes of the above sine wave amplitude in 1 second as the "frequency" of the signal, expressed by f; and the time required for the signal waveform to change once is called "period", expressed by T, in order to The unit is seconds. The distance traveled by a wave in one cycle is called "wavelength", which is denoted by λ and measured in meters. F (frequency), T (period) and λ (wavelength) have the following relationship:
Among them, c is the propagation speed of electromagnetic waves, which is equal to 3x10^8 meters/second.
The unit of frequency is Hertz, abbreviated as Hertz, which is represented by the symbol Hz. H. Hertz is a famous German physicist. In 1887, he confirmed the existence of electromagnetic waves through experiments. To commemorate him, future generations set "Hertz" as the unit of frequency.
Commonly used frequency units are kilohertz (KHz), megahertz (MHz), and gigahertz (GHz).
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