== From Near Fields to Far Fields ==
[[Image:NEOWEB11.png|thumb|450px420px|NeoScan field probe scanning the surface of a microstrip patch antenna at 2.4GHz.]]
[[NeoScan]] systems can be used as an essential tool for characterization, test and evaluation of antennas and phased array systems. It is a well-established fact that once you have an accurate estimate of the aperture fields, you can compute the far-field radiation patterns of an antenna with reasonable accuracy. This fact is based on the equivalence principle and the Huygens theory in electromagnetics. Time domain electromagnetic simulation tools such as [[EM.Tempo]] use a near-to-far-field transformation based on this principle to compute the far-zone fields of any radiating structure. In general, by far fields we mean the electric fields evaluated in the far zone of a physical structure, which satisfies the following condition:
== NeoScan vs. Conventional Near-Field Scanning Systems ==
{{#ev:youtube|https://www.youtube.com/watch?v=sjG2aua-4mk|450500|right|<b>VIDEO</b>: Characterizing an S-band microstrip-fed patch antenna using NeoScan.|frame}}
[[NeoScan]] provides a unique and highly superior alternative to the conventional near-field scanning systems. The [[NeoScan]] probes are optical and have absolutely non-metallic compositions. They are extremely small, can get very close to the surface of the radiating aperture, and provide ultra-wideband operation. Due to their non-invasive nature, [[NeoScan]] probes can generate ultra-near-field scans of the AUT. These can be used as an invaluable tool for diagnostic purposes. For instance, you can examine the inter-element coupling effects in passive and active phased arrays.