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Radio Waves

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Last updated date: 17th Apr 2024
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What are Radio Waves?

Radio waves are the waves that are a sort of electromagnetic radiation and have a recurrence with the longest frequency of radio waves from high 300 GHz to low as 3 kHz; however, someplace it is characterized as over 3 GHz as microwaves. At 300 GHz, the frequency of radio waves is 1 mm, and at 3 kHz is 100 km. They travel at the speed of light simply like all other electromagnetic speeds of radio waves do. Astronomical objects make all the waves that have normally happened. Falsely shaped radio waves are utilized in radio correspondence, radar, computer systems, broadcasting, diverse route frameworks, and various applications of radio waves.


An Introduction to Radio Waves

Radio waves are a kind of electromagnetic wave whose wavelength falls in the electromagnetic spectrum. The radio waves have the longest wavelengths among electromagnetic waves. As like all other electromagnetic waves the radio waves also travel at the speed of light. Radio waves are usually generated by charged particles while accelerating. 

Radio waves are generated artificially by transmitters and received by the antennas or radio receivers. Radio waves are usually used for fixed or mobile radio communication, broadcasting, radar, communication satellites.


Discovery

The radio wave's concept was first predicted by James Maxwell by predicting the behavior of electromagnetic waves from the Maxwell equation. The concept was later demonstrated by Heinrich Hertz. But the first-ever successful practical implementation was created by Guglielmo Marconi for which he was awarded the Nobel prize. The radio waves were used commercially for the first time in 1900 which was called Hertzian waves and later renamed as Radio waves.

There are two types of radio waves. Long waves can go around obstacles and propagate long ranges like mountains and follow the earth's contours. Since the ground is not a perfect conductor the signal gets annulated as they follow the earth's surface. The shorter waves get reflected from Earth's ionosphere and travel in a straight line and usually have a range of visible horizons. The short waves are called sky waves and the long waves are called the ground waves.

All the objects in space emit some amount of radio waves. The sun constantly emits radio waves which can be captured by Radio telescopes installed in space. These help us in planning the solar flare which may cause disruption in our communication network.

All the communications we use on earth are part of Radio waves from the mobile network to old Radio channels, from Tv to military communications. 

In space, the radio waves travel at the speed of light. But in the material medium, the speed of the Radio waves obeys the inverse square law. The main issue with the propagation of radio waves is diffraction and deflection. With the increase in the length of propagation, the loss due to transmission becomes huge and the signal might suffer data loss. To overcome this issue the concept of relay transmission is used. The relay transmission sites are also called the amplifier which receives the signal, amplifies it, and re-transmits it to the atmosphere.


Radio Waves Definition

Radio waves are typically created by radio transmitters and can be gotten by radio recipients. Radio waves having various frequencies contain different qualities of propagation in the Earth's environment. The long waves get diffracted around various impediments and follow the outline though the short waves reflect the ionosphere and get back into the great beyond of sky waves.


Frequency Range of Radio Waves

Band

Frequency of Radio Waves 

Radio Waves Wavelength 

ELF (Extremely Low Frequency)

<3kHz

>100 km

VLF (Very Low Frequency)

3 to 30 kHz

10 to 100 km

LF (Low Frequency)

30 to 300 kHz

1m to 10 km

MF (Medium Frequency)

300 kHz to 3 MHz

100 m to 1 km

HF (High Frequency)

3 to 30 MHz

10 to 100m

VHF (Very High Frequency)

30 to 300 MHz

1 to 10 m

UHF (Ultra High Frequency)

300 MHz to 3 GHz

10 cm to 1 m

SHF (Super High Frequency)

3 to 30 GHz

1 to 1 cm

EHF (Extremely High Frequency)

30 to 300 GHz

1mm to 1 cm


Types of Radio Waves

  • Low to Medium Frequency Range of Radio Waves

ELF radio waves, the least of every frequency of radio waves, have a long-range and are valuable in entering water and rock for correspondence with submarines and inside mines and caves. The most remarkable common wellspring of ELF/VLF waves is lightning. LF and MF radio groups incorporate marine and aviation radio, just as commercial AM radio.AM radio recurrence groups fall between 535 kilohertz to 1.7 megahertz. AM radio has a long-range, especially around night.

  • The Higher Frequency Range of Radio Waves

HF, VHF, and UHF are the radio waves use FM radio, communicate TV sound, public radio service, cellphones, and GPS. These groups regularly use "frequency modulation" (FM) to encode, or dazzle, a sound, or information signal onto the transporter wave.

FM brings about excellent sign quality over AM because ecological components don't influence the recurrence of how they influence adequacy. The recipient ignores varieties in amplitude.

  • The Shortwave Frequency Range of Radio Waves

Short radio waves use frequencies in the HF band, from about 1.7 megahertz to 30 megahertz. Inside that extend, the shortwave range is isolated into a few fragments, some of which are devoted to ordinary telecom stations.

  • The Highest Frequency Range of Radio Waves

SHF and EHF speak to the most elevated frequencies in the radio band and are some of the time viewed as a feature of the microwave band. Molecules noticeable all around will, in general, assimilate these frequencies, which restrains their range and applications.


Radio Waves Uses

Radio waves uses are explained in correspondence than other electromagnetic waves primarily in light of their attractive proliferation properties, coming from their enormous radio waves wavelength. Radio waves wavelength can go through the atmosphere, foliage, and most structure materials, and by diffraction can twist around blocks, and not at all like other electromagnetic waves, they will, in general, be dissipated instead of consumed by objects bigger than their frequency of radio waves. Radio waves use are found in standard communicate radio and TV, shortwave radio, route and airport regulation, cell communication, and even remote-controlled toys.


Solved Questions

1. What is The Speed of Radio Waves?

In free space (vacuum), the speed of radio waves is the quickest, the "speed of light." how quick radio waves wavelength travel is that it depends what they are traveling through, most extreme for space, slower for matter contingent upon the kind of matter and the recurrence of the waves.


Fun Facts

  1. Clerk Maxwell in the 1860s, initially anticipated that radio waves existed. His hypothesis is called Maxwell's hypothesis, portraying radio, and light waves.

  2. Heinrich Hertz exhibited radio waves in his lab in 1887. A Hertz is a radio wave unit of estimation, as is named after Heinrich Hertz.

  3. During the 1890s, Guglielmo Marconi made the main reasonable and usable radio transmitter and beneficiary

FAQs on Radio Waves

1. What are FM and AM in radio waves?

When the carrier waves (radio waves) are amplitude modulated meaning the amplitude will remain constant then those waves are called AM radio waves. When the carrier waves are frequency modulated meaning it will have a constant frequency then it is called Frequency modulated radio waves. AM are cheaper and can be transmitted to a long-range but have lower signal quality whereas the FM has great quality but faces huge transmission loss when transmitted to long distances.

2. What kind of signals are used in mobile phones?

Mobile phones and other wireless devices use the waves called Radiofrequency (RF) or non-ionizing radiation. This helps us to send and receive speech text messages, pictures and also enables us to use the internet. We are at all times surrounded by the radio waves throughout our life. In recent years there has been growing concern about the bad effects of mobile towers and the radiation it emits on the birds, animals, and other small and big organisms on earth including humans.

3. What is the difference between radio waves and radioactive waves?

Radio waves are a type of electromagnetic wave which is used in a lot of areas mostly in communication by humans. These are of non-ionizing type and are considered as the most safe waves for animals and plants. But radioactive waves are ionizing waves which are generally emitted by Radioactive Materials. The most common radioactive waves are gamma rays. These types of waves are usually harmful to living beings. But some types of radioactive waves are used in controlled conditions in medical science to cure acute diseases like cancer.

4. Where can I find detailed knowledge about radio waves?

We have curated complete materials about radio waves for the students. This material is created by the best teachers with references from advanced science journals. It is a complete cheat sheet where you will find all about the radio waves, its usage properties, their creation transmission, and all other facts. With the age called the information age, the radio waves have a very big contribution to our society and its growth. With growing technology, we are yet to see the full potential of the radio waves, which makes radio waves one of the most important topics to be thorough with.

5. What is the working principle of radar?

Radar stands for radio detection and ranging. This is a detection system which determines the size, position, and velocity of any object in a given area. It works on the principle that every object will reflect the radio waves hitting it. So if we fire radio waves towards an object and verify the time taken by the waves to reach back then we can find the distance of the object. With accurate calculation, we can also predict the size of the object. This technology is mostly used in the military to detect enemy vehicles, planes, missiles, etc.

6. How are radio waves produced?

Radio waves are created whenever electric charges quicken. Since electric charges in materials are continually accelerating as they knock around because of their warm movement, all items and materials are continually emitting radio waves wavelength as a feature of their thermal radiation. They are produced by electric charges experiencing the speed of radio waves rising, such as time differing electric flows. Radio waves are transmitted by lightning and astronomical articles.


Radio waves are produced artificially by transmitters and got by radio collectors. Radio waves are generally utilized in present-day innovation for fixed and portable radio correspondence, broadcasting, radar and radio route frameworks, communications satellites, remote computer systems, and numerous applications.

7. Explain the radio wave transmission.

The radio wave that leaves a transmitting reception apparatus begins as a sound verbally expressed into a microphone. A microphone is a gadget for changing over sound vitality into electrical energy. A microphone achieves this change by any of the various systems. For instance, in a carbon amplifier, sound waves entering the gadget cause a case containing carbon granules to vibrate. Thus, the vibrating carbon granules cause a change in electrical obstruction inside the carbon box to differ, bringing about the creation of an electrical flow of fluctuating strength.


The electric flow delivered inside the microphone goes into a speaker where the flow quality is enormously expanded.

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