Electromagnetic Waves

Radio Waves

Do you ever wonder about the working mechanism behind commonly used home devices like TV, cellular phones, or radios? We often regard it as the building block of any communication device. Further, radio waves are the key role player that helps in producing the images as seen in televisions or the sound as heard in Cellular phones. However, Radio waves are actually a type of Electromagnetic waves. Thus, they produce when fast-paced moving electrons are suddenly forced to stop at their spot due to the presence of a metal-containing high atomic number.

Moreover, a major question one may ask is what is the Electromagnetic Wave? These are waves varying in space and time where the electrical and magnetic vectors change sinusoidally to place themselves at a right angle to the direction of the propagating waves. Further, interestingly Electromagnetic waves travel at the speed of light and since they are neutral. Thus, the electrical or magnetic fields do not hinder their movement.

Further, electromagnetic Spectrum is a combination of regions of several electromagnetic waves of different frequencies and wavelengths. Thus, the seven primary regions of the Electromagnetic Spectrum include Microwave, Visible Light, Infrared, Ultraviolet rays, X-rays, Gamma Rays, and Radio Waves.

Radio Waves

Radio Waves

Introduction to Radio Waves

Radio waves are electromagnetic waves which produce due to the accelerated motion of charges in radio transmitters. Further, these electromagnetic waves have a wide range of frequencies that can go as high as 300 GigaHertz. On the other hand, they can also go as low as 3 kiloHertz. Thus, this makes them most suitably usable in Communication devices across all platforms.

Mechanism of Generation of Radio Waves

Radio Waves ideally generate using a transmitter and a receiver detects them. Further, the entire process of generating usable electromagnetic waves is done by using an Antenna to transmit energy into space. In addition, from where a receiver picks up the energy and converts it into mechanical vibrations that are heard as Sound waves.

However, the transmitter and the receiver both work at a specific frequency. Thus, the frequency can range between 3 kiloHertz to 300 GigaHertz. Since radio waves have one of the longest possible wavelengths in the entire electromagnetic spectrum. In addition, the range of reachability and transmission can be anywhere from a few miles to a few hundred thousand miles into space as well.

Radio Wave Communication System

The Radio Wave communication System primarily consists of 3 functional components. These are:

  1. Transmitter – the processing and encoding of the signal to be transmitted for communication is done using a Transmitter. Two distinct types of signals are transmitted known as Analog and Digital signals. Both have a distinctive character pattern that can be converted to the other.
  2. Communication Channel – The medium used for the transference of the signals from the transmitter to the receiver without distorting it is called as Communication Channel
  3. Receiver – The receiver receives the signal and decodes it into an understandable sound wave

Types of Radio Waves Signal

There are two types of radio wave signals which transmit, we call them Analog Signal And Digital Signal.

  • Analog Signal – The time-based signal transmission where the current or voltage change initiates the magnitude of frequency transfer. Earthquake magnitude, speed of lightning, winds, etc are calculated using Analog Signal
  • Digital Signal – Digital Signal decodes data as sequences of specific values at a constant or prefixed time value. Computers and Cellular Phones work using Digital Signal

The Importance of Radio Wave Band

Radio Wave Spectrum have been divided broadly into 9 specific frequency levels to help in utilizing the waves for specific purpose and intention. Thus, these include:

Band Frequency Range Wavelength Range
Extremely Low <3kHz >100 km
Very Low 3kHz to 30 kHz 10 to 100 km
Low 30 to 300 kHz 1 km to 10 km
Medium 300 to 3MHz 100 meter to 1 km
High 3 MHz to 30 Mhz 10 to 10 meter
Very High 30 MHz to 300 MHz 1 to 10 cm
Ultra High 300 MHz to 3 GHz 1 cm to 1 m
Super High 3 GHz to 30 GHz 1cm to 10 cm
Extremely High 30 GHz to 300 GHz 1mm to 1 cm
  • Low to Medium Frequency Radio Waves 

These low-frequency waves have a very long range and are transmissible through water and rocky surfaces easily. Therefore, we generally use them in radio communication for Submarine, Deep site mines, and Caves. Interestingly enough one of the most powerful Low-Frequency radio waves is Lightning strikes. Further, these electromagnetic frequencies transmit back and forth between the Ionosphere and Earth often resulting in distortion of satellite or airline radio signals.

  • Shortwave Frequency Radio Waves 

These are High-Frequency bandwidth radio waves that range between 1.7 MHz to 29.8 MHz with dedicated segmented slots for various Broadcast Mediums like British Broadcast Communications, Voice of America, Voice of Russia, etc. Moreover, reachable to a distance of over thousands of miles, several channels broadcast worldwide using these frequencies

  • High-Frequency Radio Waves 

Used in the Marine and Aviation satellite communication system, and as well as Amplitude Modulation (AM), these long-range radio frequency works best during night time as the ionosphere is free to easily refract the waves. Communication at this bandwidth slightly deteriorates as the penetrability of these waves hinders when metallic structures like buildings and skyscrapers create blockades.

  • Highest Frequency Radio Waves 

High-Frequency Very High Frequency and Ultra High-Frequency radio waves generally have a short-range. Further, we commonly use them in GPS navigation systems, FM Radios, Television broadcasts, Cellular Phones, etc. In addition, the reason why we regard FM sound quality as much better than AM frequency is environmental discrepancies and metal blockades in form of buildings and structures. They do not hinder the sound quality which produces. In fact, FM bandwidth ranges from 88MHz to 108 MHz.

  • Extremely High Frequency 

Also referred to as Microwaves, these short-range high bandwidth radio waves are best usable in Bluetooth devices, Wi-Fi routers, USB drives, etc. Thus, they work within a very short range and do not respond well to obstructions.

FAQ on Radio Waves

Question: What are the uses of Radio Waves

Answer 1: Radio waves have a wide range of usability. It ranges from Satellite communication to Bluetooth Application. Moreover, it is one of the primary modes of Signal transmission.

Question 2: What is the difference between digital and analog signals?

Answer 2: Analog signals are represented by continuous electrical pulse transmission while Digital Signals have noncontinuous electrical signal transmission.

Share with friends

Customize your course in 30 seconds

Which class are you in?
Get ready for all-new Live Classes!
Now learn Live with India's best teachers. Join courses with the best schedule and enjoy fun and interactive classes.
Ashhar Firdausi
IIT Roorkee
Dr. Nazma Shaik
Gaurav Tiwari
Get Started

Leave a Reply

Your email address will not be published. Required fields are marked *

Download the App

Watch lectures, practise questions and take tests on the go.

Customize your course in 30 seconds

No thanks.