Microwave communication



Microwave Communication 2944
Photo by: febris

A microwave is an electromagnetic wave with a very short wavelength, between .039 inches (1 millimeter) and 1 foot (30 centimeters). Within the electromagnetic spectrum, microwaves can be found between radio waves and shorter infrared waves. Their short wavelengths make microwaves ideal for use in radio and television broadcasting. They can transmit along a vast range of frequencies without causing signal interference or overlap.

Microwave technology was developed during World War II (1939–45) in connection with secret military radar research. Today, microwaves are used primarily in microwave ovens and communications. A microwave communications circuit can transmit any type of information as efficiently as telephone wires.

The most popular devices for generating microwaves are magnetrons and klystrons. They produce microwaves of low power and require the use of an amplification device, such as a maser (microwave amplification by stimulated emission of radiation). Like radio waves, microwaves can be modulated for communication purposes. However, they offer 100 times more useful frequencies than radio.

Microwaves can be easily broadcast and received via aerial antennas. Unlike radio waves, microwave signals can be focused by antennas just as a searchlight concentrates light into a narrow beam. Signals are transmitted directly from a source to a receiver site. Reliable microwave signal range does not extend very far beyond the visible horizon.

It is standard practice to locate microwave receivers and transmitters atop high buildings when hilltops or mountain peaks are not available. The higher the antenna, the farther the signal can be broadcast. It takes many ground-based relay "hops" to carry a microwave signal across a continent. Since the 1960s, the United States has been spanned by a network of microwave relay stations.

Words to Know

Electromagnetic radiation: Radiation that transmits energy through the interaction of electricity and magnetism.

Electromagnetic spectrum: The complete array of electromagnetic radiation, including radio waves (at the longest-wavelength end), microwaves, infrared radiation, visible light, ultraviolet radiation, X rays, and gamma rays (at the shortest-wavelength end).

A more common method of microwave transmission is the waveguide. Waveguides are hollow pipes that conduct microwaves along their inner walls. They are constructed from materials of very high electric conductivity and must be of precise design. Waveguides operate only at very high frequencies, so they are ideal microwave conductors.

Satellites and microwaves

Earth satellites relaying microwave signals from the ground have increased the distance that can be covered in one hop. Microwave repeaters in a satellite in a stationary orbit 22,300 miles (35,880 kilometers) above Earth can reach one-third of Earth's surface. More than one-half of the long-distance phone calls made in the United States are routed through satellites via microwaves.

A microwave communications tower in Munich, Germany. (Reproduced by permission of Photo Researchers, Inc.)
A microwave communications tower in Munich, Germany. (Reproduced by permission of
Photo Researchers, Inc.
)

The weather and microwave communication

Raindrops and hailstones are similar in size to the wavelength of higher-frequency microwaves. A rainstorm can block microwave communication, producing a condition called rain fade. To locate incoming storms, weather radar deliberately uses shorter-wavelength microwaves to increase interaction with rain.

Microwave communication is nearly 100 percent reliable. The reason is that microwave communication circuits have been engineered to minimize fading, and computer-controlled networks often reroute signals through a different path before a fade becomes noticeable.

[ See also Antenna ]



User Contributions:

1
Pam
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Sep 28, 2007 @ 7:07 am
Intresting information
I need more for some reason
2
Iddi
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Aug 30, 2008 @ 6:06 am
The article is really nice,I am a microwave engineer,the article explains brief.I have gained somthing from this article,keep it up guys and demploy another article that give detailed information of problems,challenges and solutions that are encoutered in the Digital microwave communications.
cheers all...
with regards,
Iddi Mziray
3
g.venmnanivanan
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Aug 24, 2009 @ 6:06 am
EXCELLENT.thank you for this and i need more information like this.
4
RIS Student
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Nov 17, 2009 @ 7:07 am
Very good article, thank you for putting it up, I can now do my reports : )
5
your mom!!!
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Jan 23, 2010 @ 11:23 pm
good article(: im doing a report on the microwave oven for some weird national history day project that is required and confusing.

but the microwave oven uses microwaves of radiation to cook food and this article helped explain what exactley what the micro-waves are(:
6
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Nov 26, 2010 @ 8:08 am
this information is very helpfull if i could rate is it would be 5 stars
7
Sheen
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Mar 2, 2012 @ 6:06 am
Excellent,..Thanks for sharing, I need more information.
8
ambika
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Dec 31, 2013 @ 9:09 am
It,s realy veary useful.i need more details about this.
9
jose e. rosa
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Feb 8, 2015 @ 2:14 pm
i love it all thank you bless you and your family (73 )
10
liia
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Mar 26, 2015 @ 9:21 pm
thanks much.. this was really helpful... i am honestly grateful
11
Jescelmae Acaso
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Jul 12, 2015 @ 12:00 am
what are the filters necessary to counter high level of noises and EMC?
12
John
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Aug 22, 2015 @ 12:00 am
Great article. Help me with my inquiry. My hope is that was is posted is accurate and informative.
13
Takura Maposa
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Nov 10, 2016 @ 4:04 am
This is a helpful article, thank you so much. I'm looking foward to read other articles from you focusing on Electronic Communication System. Moreover you should put some more equations
14
slimy
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Nov 21, 2017 @ 5:17 pm
What frequency band does this cover?
From 1 GHz ( 30 cm) to 300 GHz (1mm)?
15
Wamala B. Emmanuel
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Oct 5, 2018 @ 2:02 am
Thanks for sharing with us may the almighty bless you abundantly

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