# Frequency Calculator-How to calculate frequency?

The frequency of a radio wave is the number of wave cycles it generates in one second. It is calculated by dividing the velocity of the radio wave (speed of light, c =299 792 458 m/s) by wavelength (λ). Wavelength is the length of one full wave in metres. Mathematically, Frequency = f = c/λ. The frequency is expressed in “per second” or “Hertz”, abbreviated as Hz. In real life networks, the frequency is expressed in Megahertz (MHz) or Gigahertz (GHz).

Mobile cellular networks communicate with mobile phones through radio waves. Irrespective of which technology is being used, e.g. 4G LTE (Long Term Evolution) or 5G NR (New Radio), once the mobile signal is ready to be sent from the antennas of a mobile network to the mobile phones, it is transmitted in the air interface in the form of electromagnetic radiations. These radiations are sent at specific frequencies in a highly controlled way to ensure that they do not interfere with other radio waves that may be operating at similar frequencies.

Mobile cellular networks communicate with mobile phones through radio waves. Irrespective of which technology is being used, e.g. 4G LTE (Long Term Evolution) or 5G NR (New Radio), once the mobile signal is ready to be sent from the antennas of a mobile network to the mobile phones, it is transmitted in the air interface in the form of electromagnetic radiations. These radiations are sent at very specific frequencies in a highly controlled way to ensure that they do not interfere with other radio waves that may be operating at similar frequencies. If you look at the highly simplified diagram below, you may note that there is a link between the base station of a 4G LTE network and a mobile phone that is receiving the 4G signal. This link is the radio wave that operates between the network and the mobile phone at certain frequencies. The frequencies employed by GSM networks were in the order of 890 MHz and upwards. The latest 5G networks use frequencies in different bands, including the sub 1G Hz band as well as high bands like 6 GHz+.

Radio waves travel through the air at the speed of light, which is 3 x 108 metres per second or 299 792 458 meters per second, to be exact. It means that a radio wave can cover almost 300 million meters or 300 thousand kilometres in one second, which is quick. However, when radio waves are deployed in mobile networks, the coverage range of a regular radio base station, called a macro base station, is in tens of kilometres. The range of a radio wave depends on many factors, including transmission power.

The formula for calculating the frequency of a radio wave:

Frequency = f = c/λ;

where λ is the wavelength in metres and c = 299792458 m/s.

Wavelength (λ) is the length of one complete wave cycle from start to finish. It is the distance between the start and end of the cycle and is expressed in metres. If you are using our frequency calculator above, you can enter a value in metres, e.g. 2m and the calculator will give you a value in Hertz (cycles per second) for theoretical reasons and in megahertz (MHz) for more real-life situations.