Radio Frequency or RF Frequency refers to the type of electromagnetic radiation used mostly in the communications industry. In this blog post, you will learn more about the uses of radio waves, the radio frequency applications and the radio waves frequency range.
How Did Radio Frequency Waves Come About?
The concept of radio frequency can be dated back to the 1870s when a Scottish physicist, James Clerk Maxwell embarked on research called the unified theory of electromagnetism.
Among many things, it proved the following:
- It predicted the possibility of a coupled magnetic field and electric field to travel as an electromagnetic wave, through space.
- The theory, now known as Maxwell’s Equation, proposed the possibility of light to comprise short wavelengths of electromagnetic waves.
It is based on the premise of this theory that Heinrich Hertz, a German physicist, in 1887, put Maxwell’s theory to test. The demonstration involved the generation of radio waves in the lab, and the outcome showed that the waves possessed some similar properties as light. These properties include but are not limited to: polarization, standing waves, diffraction and refraction.
What is RF Frequency in the Modern World?
The experiments by both Maxwell and Heinrich helped lay the framework for what we have today. Now, Radio Frequency (RF), according to Wikipedia, is the “oscillation rate of an alternating electric current or voltage.”
It can also be used to describe the following:
- The oscillation rate of a mechanical system in a frequency.
- The oscillation rate of a magnetic.
- The oscillation rate of an electromagnetic field.
Going by these definitions, the radio waves wavelength, in addition to being the longest, typically range between 20 kHz and 300 GHz. The usage in Radio Frequency (RF) technologies and or applications is due to the frequencies from where the energy coming from an oscillating current are radiated off into the space, in the form of radio waves.
Contrasting between RF Frequency and Radio Waves
A slight difference exists between Radio Frequency (RF) and radio waves, even though they are sometimes regarded as one.
Here are some of the differences:
- The wavelength in radio waves is inversely proportion to the radio frequency.
- Charged particles, which have been accelerated, lead to the radiation of radio waves, while the electric currents that oscillate at Radio Frequencies (RF) do not have the properties shared by lower audio frequency alternating current or direct current.
Radio Waves’ Generation
The waves are generated in a wide range of ways, including via a time-varying electric currents, and radio noise produced by lighting and other forms of naturalized processes.
The simplest explanation is that radio waves are generated by a transmitter and a receiver detects it. The next processes include the passage of the radio transmitter through the antenna. This enables the transmitter to send energy into space and for the receiver to receive or pick up the sent energy from the space.
The Types of Radio Waves
Different kinds of radio waves exist and choosing the one to work with depends on the typical applications.
Here are some quick facts about the types of radio waves:
- They are labelled or categorized into bands or ranges, such as: Low Frequency (LF), Medium Frequency (MF) and High Frequency (HF).
- Each of the ranges or bands tend to have an increase of frequency that corresponds to the power of 10 (or the order of magnitude).
With that being said, here are some of the options:
a. Low-to-Medium Frequencies
These are the lowest in the “waves chain.” Out of these, the Extremely Low Frequency (ELF) stands out. It refers to the radio wave with less than 3kHz of frequency and up to 100 km of radio waves wavelength.
The benefits of the ELF include:
- These waves are naturally-generated, usually through lightning.
- The waves can be used for a variety of purposes, including entering rocks and water for an onward communication with caves, submarines and mines.
- Extremely Low Frequencies (ELFs) are relied on due to the longer ranges.
On the flipside, you may want to distance yourself from using the ELF due to these reasons:
- The waves can “bounce back and forth” between the ionosphere and the earth.
- The disturbances created by the lightning tend to disrupt the transmission of radio signals.
The Low Frequency (LW) and Medium Frequency (MF) ranges tend to incorporate both aviation and marine radio. They also support the Amplitude Modulation (AM) radio, typically the one that falls between 535 kHz and 1.7 MHz
One of the selling points of the Amplitude Modulation (AM) is the long-range, especially at night. On the downside, the long-range is often susceptible to interferences that tend to negatively affect the sound quality.
b. Higher Frequency Ranges
These are the radio waves with a higher frequency range. They often use a power of 10 or the order of magnitude.
Examples of the radiofrequency waves that fall into the higher frequency ranges are:
- Very High Frequency (VHF)
- Ultra High Frequency (UHF) and;
- High Frequency (HF)
These ranges or bands often use Frequency Modulation (FM) bands for the communications. The benefits of FM over AM include:
- The radio frequencies are anywhere between 88 MHz and 108 MHz.
- Frequency Modulation (FM) bands are not often constrained by the ecological components, which is the reason why they hardly experience lower signal quality.
c. Highest Frequency Ranges
As the name suggests, these are the radio waves with the highest frequency ranges. Some of the attributes include:
- These ranges are often regarded as a feature of the microwave band and;
- They are the most-elevated frequencies in the radio band.
The Super High Frequency (SHF) and the Extremely High Frequency (EHF) are the most-prioritized here.
SHF vs. EHF
Despite being the most-elevated of frequencies in the radio band, the SHF and the EHF also differ. For example, the SHF is commonly used for applications requiring shorter ranges of connections. Examples are Universal Serial Bus (USB), Wi-Fi and Bluetooth.
The Super High Frequency (SHF) is preferred over the Extremely High Frequency (EHF), due to the less susceptibility to damage or interference by air.
Generally, the highest frequencies, such as EHF and SHF have shorter wavelengths that support the direction of signals to satellite dish antennas.
However, one challenge with these frequency ranges is the assimilation or absorption of the frequencies by the molecules in the air. This is one of the reasons why these frequency ranges don’t always go beyond certain applications and ranges.
d. Short Radio Waves
These refer to the radio frequency (RF) waves that use the frequencies in the High Frequency (HF) band. These frequencies range anywhere from 1.7 MHz and 30 MHz.
Attributes of the short radio waves include:
- Bouncing off of the signals from the ionosphere and the rebounding of the same hundreds of miles from the origin.
- Short radio waves can also be isolated into different fragments and segments and used for dedicated telecommunication stations, such as Voice of Russia and the Voice of America.
Radio Frequency Applications
Several frequencies of radio waves are used for different purposes, but the common ones are mobile phones, transmitters, computers, televisions and receivers. These frequencies, depending on the ranges, can also be used in the following applications:
- Remote-controlled toys
- Control circuits
- Wireless computer networks
- Ham radios
- Military communication devices and;
- Telephones
The applications of radio frequency waves wouldn’t be completed, without highlighting some of the industries benefiting from it. Examples are:
- Wireless Devices: examples are Bluetooth, Cellphones, Wi-Fi, television broadcast stations and satellite communication systems.
- Medical Applications/Devices: radio frequency waves are also relevant in the medical industry. In this case, they are used either in the forms of electrical currents or radio waves (electromagnetic waves).
Today, the usages of radio frequency for medical applications have transcended the above and now include:
- The use of radio frequency fields in Magnetic Resonance Imaging (MRI). This aids in the generation of the images of the human body.
- Diathermy
- Electrosurgery scalpels, which are used for cutting and cauterizing, during laboratory operations.
- Cancer treatment and;
- Hyperthermy
Radio Waves Uses
Radio frequency waves are commonly used in the medical and communications industries. However, the use cases are much more than those.
Today, you can find these ranges of frequencies applied to different places. For example, they are now used standardizing the communications via radios and TVs, as well as enabling remote-controlled toys.
Worthy of mentioning is that the RF field usages in the several types of wireless communications is enhanced by the use of transmitters and antennas.
Beyond wireless communication applications, Radio Frequency (RF) fields have now been used in the following:
- Garage door openers
- Microwave ovens and;
- Wireless devices, such as computer mice, TV remote controls and computer keyboards.
Conclusion
The use of Radio Frequency (RF) waves aids in the electromagnetic radiation that has been useful in different key industries. From enabling wireless communications to boosting communications in the home and office, the use of RF waves goes a long way.
Of course, the capabilities tend to differ by the frequency ranges. For the best results, choose from the higher frequency ranges and the highest frequency ranges.
