Examples of radio waves in science and technology are; telecommunication signals, digitalized audio broadcasting waves, electromagnetic radiation from hydrogen nuclei in the body, radiant emissions from planetesimals, and GPS signals for navigation.
This article discusses examples of radio waves in science and technology, as follows;
1). Telecommunication Signals (as one of the Examples of Radio Waves)
Radio waves are an ideal option for transmission of signals in telecommunication systems. This is because of their characteristics that include long wavelength and low frequency; which reduce the dangers associated with exposure.
Radio waves carry various types of signals in telecommunication, including analog, digital and hybrid (analog-digital) signals. These three categories can also be referred to as the types of radio waves, when classified on the basis of transmission-mode.
The basic concept behind radio wave signals is telecommunication involves electromagnetic activation of a transmitter, which emits radio waves (by radiation) into the atmosphere/surroundings, so that a receiver may detect and decode these wave-signals .
A common instance of the transmission and reception of radio waves in telecommunication is wireless transfer of information with smart devices like mobile phones and digital repeaters . In most cases, the information is transmitted and received in form of electromagnetic radio waves that have been ‘encoded’ with this information through processes like modulation and digitalization.
Modulation and digitalization serve the purpose of encapsulating information within a definite range of radio wave-streams. For modulation, this is done by modifying the frequency and/or amplitude of the waves to produce Amplitude-Modulated (AM) and Frequency-Modulated (FM) waves that can easily be decoded by a receiver that is tuned to the same amplitude or frequency range.
Digitalization is the conversion of audio and visual information into numerical strings before they are transmitted as radio waves. This mode of transmission is more modern and efficient for high-quality decoding.
It must be noted that the concept of radio wave propagation in small-scale telecommunication systems like cellphones, is very similar to other radio wave concepts like broadcasting and navigation.
2). Digitalized Waves in Audio Broadcasting
The digitalization of broadcasting is a concept that describes the transition from earlier-used analog methods to modern, digital methods, for publishing information. We use the term ‘digital audio broadcasting’ when the signals being transmitted are predominantly in audio format.
A digital radio wave is a stream of electromagnetic signals that have been encoded into strings of numbers which can be decoded easily by a digital receiver.
Digital audio broadcasting (DAB, DAB+) works by encoding and decoding; where sound information that passes through an electronic system, is converted into digital format, so that it becomes enclosed in a series of numbers before being transmitted .
This is different from analog broadcasting, which encloses information in a definite range of wave-frequencies or amplitudes.
With digital audio broadcasting, it is easier for a receiver to decode information which it has detected, because digital signals are definite, and do not vary in strength across a range of frequencies . This also means that digital radio waves can be decoded with more clarity and quality, than analog waves.
3). Electromagnetic Radiation from Hydrogen Nuclei in the Body (as one of the Examples of Radio Waves)
Hydrogen is significant in Magnetic Resonance Imaging (MRI), due to its widespread distribution in the body, and its susceptibility to magnetic field-alignment. These attributes make it possible to detect the electromagnetic pulses from hydrogen atoms, and use this detection to derive information about the internal components of the body.
It is possible to obtain signals from the nuclei of hydrogen atoms in the body, when a magnetic field is imposed on these nuclei, as it causes the protons to align with the magnetic field poles . Since these nuclei are widely distributed in the body’s water and fat reserves, the signals detected can easily be used to visualize organs, tissues and bones.
Radio waves are the main form of electromagnetic radiation used in magnetic resonance imaging, because they pose less harm to the body than other EM waves.
It must be noted that an MRI system does not necessarily produce radio waves, but rather provides a magnetic field which interacts with the radio waves in the electromagnetic spectrum emanating from hydrogen atoms in the body.
Radio wave usage in MRI represents an important aspect of biomedical technology, and is useful for diagnostic and treatment purposes.
4). Radiant Emissions from Planetesimals
Astronomical objects emit radio waves among other forms of radiation, as a result of the presence of electromagnetic fields around these objects.
These fields are in turn produced by metallic and non-metallic elements that constitute planetesimals.
Hydrogen is an example of an abundant element that contributes to the electromagnetic field of planetesimals, alongside metals like iron and magnesium.
Radio waves emitted in space form the basis of practical radio-astronomy; which involves the use of telescopes and space-based satellites to study the characteristics of planetesimals through their electromagnetic emissions .
5). GPS Signals for Navigation (as one of the Examples of Radio Waves)
GPS receivers decode both microwaves and radio waves transmitted and relayed by satellites.
The radio waves used in global positioning systems are usually complex and modulated due to the distance of transmission, to enable them yield high-quality information when decoded by Earth-based receivers .
In navigation, radio waves are effective for providing signals on geographic coordinates, using real-time data collected by satellites . The use of radio navigation is common in air and maritime systems.
Examples of radio waves are;
1. Telecommunication Signals
2. Digitalized Waves in Audio Broadcasting
3. Electromagnetic Radiation from Hydrogen Nuclei in the Body
4. Radiant Emissions from Planetesimals
5. GPS Signals for Navigation
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