Gigahertz is generally known as GHz in it?s abbreviated form. Hertz is the standard unit of measuring frequency and Giga is it?s multiplier of 1 billion times. So Gigahertz means one billions of cycles/ periods per second.
Hertz is generally used in measuring frequency while GHz is commonly used in measuring computer performance or radio frequencies. In terms of computer, GHz mostly refers to the clock speed of the CPU (Central Processing Unit) while in Radio it is used to define the bands of electromagnetic spectrum.
When CPU clock tick faster, the manipulates of data and instructions also becomes higher. So the processing of CPU is directly proportional to manipulating the data. The faster processor has faster speed and measured as in greater Gigahertz. Intel and advanced processor introduced 1Hz processor in year 2000. At present the general processor is available till 4 GHz.
In radio GHz refers to measured different bands that have different sorts of function and name. For example S-Band has a band of spectrum between 2 and 4 GHz whereas L-band have 1 and 2 GHz. S-band is used in common technologies such as Bluetooth, wireless internet (WiFi) and cordless telephones while L-Band is used for satellite communications and Global Positioning Systems (GPS). Besides these some other bands come in the GHz range are Ku and Ka that are used by satellites and by police radar guns.
The invention and uses of semiconductor makes it possible to generate such a high range of frequencies. These semiconductors are boon for the electronics world and these have created revolution in the electronic world.
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