Post on 30-Dec-2015
description
transcript
Pg 1 of xxAGI www.agi.com
STK 3D Electronically Steerable Phased Array Antenna Plugin
Trey Spetch, Jerry Odhner, and Kristen Jones
Pg 2 of 15AGI www.agi.com
What is a 3D Steerable Phased Array Antenna?
• Flat Panel Array of Elements
• Beam Electronically Steered by Varying Phase Across Elements
• Steerable in Both Azimuth and Elevation
Pg 3 of 15AGI www.agi.com
Applications of Electronically Steerable Flat Panel Arrays
• Over the Horizon Radar
• Missile Searching and Tracking (Patriot Missile)
• Ship-Borne Radar
• Aircraft Antennas– Must be conformal with aircraft– No dishes allowed– Large apertures achievable
Pg 4 of 15AGI www.agi.com
STK Static Antenna Patterns Not Suitable to Model Phased Array Beam
90 Degree Elevation Beams 45 Degree Elevation Beams
1 GHz, 1m Aperture 1 GHz, 1m Aperture
Array Antenna Dish Antenna Array Antenna Dish Antenna
Pg 5 of 15AGI www.agi.com
Antenna Notional Model
m = 4
n = 3
/2
Crossed-Dipole Element
Pg 6 of 15AGI www.agi.com
Dihedral Angles to Boresight and ToObject
• Dihedral Angles for Boresight and ToObject (
Pg 7 of 15AGI www.agi.com
Plugin Model
ToObjectAzToObjectAz
ToObjectElToObjectEl
m, n, m, n,
CoordXform
G(m, n, )
BoresightVertBoresightVert
BoresightHorizBoresightHoriz
GainToObjectGainToObject
Pg 8 of 15AGI www.agi.com
Beam Steered to Invisible Vehicle
Pg 9 of 15AGI www.agi.com
Creating and Attaching Plugin Scripts
There are several kinds of plugins (constraints, transmitter and receiver models, custom antenna gain, etc)
For a custom antenna gain plugin, select the plugin file on the receiver properties panel under Antenna… Details…
Languages: Matlab, Perl, and VBScript.
The examples scripts that AGI provides are a good place to start. You can then add any additional input variables as needed and write functions to do custom calculations.
Pg 10 of 15AGI www.agi.com
Plugin Code
• AntennaGainPlugin.vbs.doc
Pg 11 of 15AGI www.agi.com
Directivity Visualization Using STK Coverage
Pg 12 of 15AGI www.agi.com
5 x 5 Array, 1 GHz
Effect of Changing Array Dimensions
Increasing the number of elements along one axis of the antenna decreases the beamwidth in that direction
5 x 10 Array, 1 GHz
10 x 10 Array, 1 GHz
Pg 13 of 15AGI www.agi.com
Effects of WavelengthFor a given panel aperture size, the beamwidth decreases with wavelength
1 meter array (2x2), 500 MHz
1 meter array (7x7), 1 GHz
1 meter array (33x33), 5 GHz
Pg 14 of 15AGI www.agi.com
Conclusion
• STK Plugins allow dynamic beam shaping for antennas based on custom equations
• Any geometric variable or scalar value can be input to the plugin
• Allows extremely accurate modeling of link margins for phased arrays and other custom antennas
Pg 15 of 15AGI www.agi.com
Questions?