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Wave Theory
What is it?
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A wave is a pattern of a signal, such as that generated by sound and light, that changes at regular intervals.
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Radio waves are part of a larger group of waves classified all together as electromagnetic radiation.
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This large group of waves is broken down into smaller groups based on their frequencies and wavelengths.
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Frequency describes the number of waves that pass a fixed place in a given amount of time.
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So if the time it takes for a wave to pass is in 1/2 second, the frequency is 2 per second.
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Frequency is measured in Hz (hertz).
Frequency (f):


1 wave
1 wave
2 wave
3 wave
4 wave
Amplitude
1 cycle
1 oscillation
Low frequency radio wave
1 frequency per second.
High frequency radio wave
4 frequencies per second.
Wavelength: (λ)
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the distance between successive crests of a wave especially points in a sound wave or electromagnetic wave.
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A repeating pattern of traveling energy like light or sound.
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Wavelengths are measured in:
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kilometers
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meters
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millimeters
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micrometers
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nanometers
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picometers
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femtometers
Wavelength (λ)
Wavelength
A wavelength is a measure of distance between two identical peaks (high points) or troughs (low points) in a wave.

Frequency & Wavelength Relation:
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Electromagnetic waves always travel at the same speed (299,792 km per second).
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In the electromagnetic spectrum, there are many different types of waves with varying frequencies and wavelengths.
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They are all related by one important equation: Any electromagnetic wave's frequency multiplied by its wavelength equals the speed of light.
FREQUENCY OF OSCILLATION x WAVELENGTH = SPEED OF LIGHT
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We can use this relationship to figure out the wavelength or frequency of any electromagnetic wave if we have the other measurement.
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Just divide the speed of light by whichever measurement you have and then you've got the other.
10^5
f
10^9
10^12
10^14
10^15
10^16
10^19
λ
10^3
Radio
10^-1
10^-3.5
10^-6
10^-6.5
10^-8
10^-11
Microwave
Infrared
Visible light
Ultraviolet
X-ray
Gamma rays
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Radio waves are electromagnetic waves with the longest wavelength and lowest frequencies.
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A radio receiver converts radio waves into sound waves that you can hear.
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The radio spectrum is the part of the electromagnetic spectrum from 3 Hz to 3000 GHz.
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The bandwidth of a radio signal is the difference between the upper and lower frequencies of the signal.

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Below is an illustration of how electromagnetic radiation is broken down into groups.
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The electromagnetic (EM) spectrum is the range of all types of EM radiation.
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Higher frequencies have shorter wavelengths, and signals with shorter wavelengths have more trouble penetrating obstacles like walls and floors.
FREQUENCY OF OSCILLATION
=
SPEED OF LIGHT
WAVELENGTH
SPEED OF LIGHT
WAVELENGTH
=
FREQUENCY OF OSCILLATION
A wavelength is a measure of distance between two identical peaks (high points) or troughs (low points) in a wave.
Spectrum
Radio Spectrum
f
3 kHz
30 kHz
300 kHz
3 MHz
30 MHz
300 MHz
3 GHz
30 GHz
VLF
LF
MF
HF
VHF
UHF
SHF
EHF
100 km
λ
10 km
1 km
100 m
10 m
1 m
10 cm
1 cm
Mobile phone, Bluethooth, wireless LAN, GPS
1 mm
300 GHz
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To prevent interference between different users, the generation and transmission of radio waves are strictly regulated by national laws, coordinated by an international body, the International Telecommunication Union (ITU).
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Below is the mobile revolution in wireless telecommunication.
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All of them refer to the technology used by the mobile carrier and device itself; they have different speeds and features that improve on the generation prior to it.
Wireless mobile telecommunications technology timeline
AMPS
GSM
GPRS
EDGE
UMTS
LTE
1985
Bell Labs
1992
ETSI
1995
ETIS
2003
3GPP
2004
3GPP
2013
3GPP
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Each of those generation here are have different modulation scheme, different technology.
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1G (1st Generation): (voice)
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This did not have data.
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Only voice.
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Developed by AMPS
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2G (2nd Generation): (digital voice + data)
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GSM (Global System for Mobile), CDMA.
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Developed by ETSI
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2.5G added dedicated digital data called GPRS (General Packet Radio Services ).
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Data rate 54 kbps.
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2.75G EDGE(Enhanced Data rates for GSM Evolution).
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Introduces 8PSK.
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Datarate 170 kbps.
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3G (3rd Generation): (voice + data + video call )
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UMTS (Universal Mobile Telecommunications System).
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Developed by 3rd Generation Partnership Project(3GPP).
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3.5G, HSPA (High-Speed Packet Access), data rate 2mbps.
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3.75G, (HSPA+).
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4G (4th Generation): (digital + data + video call)
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LTE (Long-Term Evolution).
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Video conferencing.
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1Gbps for stationary.
Audible Frequency
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A range of frequencies, characteristic of signals audible to the normal human ear.
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The SI unit of audio frequency is the hertz (Hz).
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The generally accepted standard range of audible frequencies is 20 to 20,000 Hz.
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Here are some notable voice produced:
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8.18 Frequency - Lowest organ note.
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32.70 Frequency - Lowest C on piano.
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85-180 Frequency - Average Male voice.
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165 to 255 Frequency - Typical adult Female voice.
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2093 - Highest note for flute.
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