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NeoScan for Antenna Characterization

52 bytes added, 16:07, 2 October 2016
/* A Perfect Solution for Characterizing High-Power Antenna Systems */
== A Perfect Solution for Characterizing High-Power Antenna Systems ==
{{#ev:youtube|https://www.youtube.com/watch?v=oAa-XqE9H1g|380|right|<b>VIDEO</b>: Characterizing an X-band slotted waveguide array.| frame}}
Test and evaluation of high-power antenna systems or active phased arrays is a daunting process. Special considerations must be taken into account when measuring high-power radiating systems in an anechoic chamber including operator's safety and fire hazards. The problems are multiplied when using a near-field scanning system whose metallic receiver probe has to be positioned at a far enough distance from the transmitting antenna under test. In contrast, [[NeoScan]] probes can handle field intensities as large as 2MV/m and can even withstand higher radiated power levels. The non-invasive EO probes can be placed very close to the surface of the high-power radiating aperture, while the optical mainframe and RF processing back end reside much farther at a reliable distance from the aperture.
EMAG's unique probe and optical processing technology utilizing polarization maintaining (PM) optical fibers allows standoff distances as long as 50 meters between the probe location at the aperture of the high-power array and the optical mainframe. This enables you to readily characterize very high-power antenna systems very accurately in a totally non-invasive manner without any serious safety or logistic concerns. In other words, you don't need to attenuate or lower the transmitted power levels of your antenna system to meet safety requirements or make it possible for the conventional metallic probes to operate in the proximity of the antenna aperture without interfering with it. With [[NeoScan]], you can characterize your high-power antennas or active phased arrays under their true or nominal operating conditions.
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{{#ev:youtube|https://www.youtube.com/watch?v=oAa-XqE9H1g|480|left|<b>VIDEO</b>: Characterizing an X-band slotted waveguide array.| frame}}
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You can use [[NeoScan]] for measurement of different types of antenna structures and array topologies. In certain cases, prior physical knowledge of field distributions may facilitate and expedite the scanning process. For example, the figure below shows an X-band slotted waveguide array operating at 9.4GHz. From the physics of such structures, you know that the fields are highly localized close to the centerline of the waveguide array. In addition, the tangential field component parallel to the direction of the slots is zero. Therefore, if the goal of near-field scanning is to compute the far-field radiation patterns, only one tangential field component needs to be mapped. For a complete near-field characterization, however, you may want to measure the normal field maps, too.
 
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[[Image:NEOWEB15.png|thumb|left|550px|Measuring the fields at the aperture of an X-band slotted waveguide antenna array at 9.4GHz.]]
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[[Image:NEOWEB8.png|thumb|left|240px|The aperture field distribution of the slotted waveguide array.]]
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[[Image:NEOWEB16.png|thumb|left|240px|The far-field radiation pattern of the slotted waveguide array.]]
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