Difference between Radio Waves and Microwaves

The electromagnetic wave spectrum is a very wide theory that covers all types of sound waves in different frequencies and ranges. One of the most widely used waves is radio waves and microwaves. They both sound similar, but they have a good amount of differences between them.

In this post, we will learn the difference between radio frequency and microwave frequency.

What is Transmission Media?

To transmit any data, a medium is required. This medium is nothing but a way to communicate data from one end to another. So, based on this, two types of media are used – guided and unguided.

Guided media means anything that you can see and will properly terminate from one end to another in a fixed way (like wires and cables).

Unguided media means anything that you cannot see and has no termination (electromagnetic waves).

So, in this article, as we are studying the difference between radio and microwaves, we will thus see the concept of unguided media further.

What is the Electromagnetic Spectrum?

Before we start this post, let us first understand the basics. We all live in a world that is surrounded fully by a wide variety of electromagnetic waves. Some are visible and some are not. This range of frequencies is nothing but an electromagnetic spectrum. These waves are of different wavelengths and frequencies. It starts from 1 Hz and can go up to 10²⁵ Hz.

Generally, it can be represented by a scale where a certain set of frequencies come in one particular type. As the frequency increases, wavelength decreases.

This spectrum has the following order –

Gamma rays (nuclear theory)
X-rays (medical appliances)
Ultraviolet (sun)
Visible (tube lights, bulbs, and other visible sources of light)
Infrared (night vision rays)
Microwaves (microwave ovens, structure of galaxies and stars)
Radio waves (TV, mobile communication).

The order starts with high-frequency low-wavelength waves and ends with low-frequency high-wavelength waves. In the whole range comprising seven types of waves, every type has its particular set of frequencies.

So, in short, this whole scale of waves is defined as the electromagnetic spectrum. It is important to study this spectrum because then only, we can decide what frequencies we need to work on for a particular application.

What is a Radio Wave?

Radio waves have the lowest frequency range. Radio waves come in the range below 3 x 10¹¹ Hz. Radio waves have a wavelength of more than 1mm. This frequency is not practically used, so in general terms, a radio wave starts from 3 kHz to 300 GHz. These waves are generated in the conducting wires with the help of accelerated movement of charges.

The main application of radio waves is radio and television communication systems. They are easy to generate, can penetrate objects (that is why it is used majorly for communication because data can travel anywhere) and also, is omnidirectional (can travel in all four directions at a time).

What is a Microwave?

Microwaves have a frequency range higher than radio waves. Microwaves come in the range of 3 x 1011 – 1013 Hz. Microwaves have a wavelength between 1 mm – 25 μm. This frequency is not practically used, so in general terms, a microwave starts from 300 kHz to 300 GHz. The frequency is generated through specific vacuum tubes like klystrons and magnetrons.

The main application of microwaves is military aircraft radar and antenna systems. Similar to radio waves, microwaves too can penetrate but is unidirectional in nature. It requires a fixed antenna set to divert the waves in a proper channel.