Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space:...
-
Upload
joella-wells -
Category
Documents
-
view
232 -
download
1
Transcript of Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space:...
![Page 1: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/1.jpg)
Parabolic Dish Antennas
![Page 2: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/2.jpg)
An Antenna is :An Antenna is :
An An effective interface between the radio and free space:
Radio Antenna
Free space
For Terrestrial Communications, a antennas must be directional:
Radio
![Page 3: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/3.jpg)
Terrestrial Microwave Antennas for Point-To-Point Communication • Terrestrial antennas generate a beam of RF signal to
communicate between two locations.• Point-To-Point communication depends upon a clear line of sight
between two antennas. • Obstructions, such as buildings, trees or terrain interfere with the
signal.• Depending upon the location, usage and frequency, different
types can be utilized.• We will address the basic characteristics of these various
types…
![Page 4: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/4.jpg)
Basic Parabolic Antenna TypesBasic Parabolic Antenna Types
Standard Standard Parabolic Parabolic AntennaAntenna
Shielded Shielded (Radomes) (Radomes)
AntennaAntenna
GRIDPAKGRIDPAK®® AntennaAntenna
Focal Plane Focal Plane AntennaAntenna
![Page 5: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/5.jpg)
Standard Parabolic AntennaStandard Parabolic Antenna
• Basic Antenna
• Comprised of
– Reflector
– Feed Assembly
– Mount
![Page 6: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/6.jpg)
Shielded AntennaShielded Antenna
• Absorber-Lined Shield
• Improved Feed System
• Protection Against Ice, Snow and Dirt
• Better against the wind
![Page 7: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/7.jpg)
Focal Plane AntennaFocal Plane Antenna
• Deeper Reflector
• Edge Geometry
• Slightly Lower Gain
![Page 8: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/8.jpg)
GRIDPAKGRIDPAK®® Antenna Antenna
• Grid Reflector
• Low Wind load
• Below 2.7GHz
![Page 9: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/9.jpg)
Antenna EfficiencyAntenna Efficiency
Well-designed antennas have efficiency ratings of 45 - 65%
Efficiency Factor Affected By :
• Signal Strength,
• Blockage & Obstructions
• Reflector Surface
Efficiency can never be 100%
![Page 10: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/10.jpg)
Calculating the Focal Point
• In order to determine the optimal location for the antenna feed, or receiver, you must calculate the focal point.
• Using the following formula:» F= D2 / 16d
– Where • F = focal point• D = Diameter of the dish• d = depth of dish
![Page 11: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/11.jpg)
Focal Point
The point at which the RF signals meet after reflecting off of the parabolic curve of the antenna.
![Page 12: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/12.jpg)
Calculating the Focal Point
• If you have a Parabolic Dish antenna that is 12” in diameter and 3” deep where would the focal point be located?
• Use the formula: F= D2 / 16d• 12” squared = 144”,• 144” divided by (16 x 3”) or 48”• 144/48”=3”• The focal point is 3”.
![Page 13: Parabolic Dish Antennas. An Antenna is : An An effective interface between the radio and free space: Radio Antenna Free space a For Terrestrial Communications,](https://reader035.fdocuments.us/reader035/viewer/2022062304/56649d0e5503460f949e4260/html5/thumbnails/13.jpg)
Calculation Worksheet
• Go to the “Handouts” tab on the classroom website dashboard,
• Open the “Parabolic Dish Calculations Worksheet”,
• Work the problems on the worksheet and upload the completed worksheet to the classroom website.