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Near-field Scanner
Electromagnetic near-field scanner (NFS) is a measurement system to determine a spatial distribution of an electrical quantity provided by a single or multiple field probes acquired in the near-field region of a device under test possibly accompanied by the associated numerical post-processing methods enabling a conversion of the measured quantity into electromagnetic field. Depending on a signal receiver detecting the probe signal, voltage as a function of time or frequency is a typical measured quantity. It should be underlined that as the DUT may be considered any object ''radiating or storing'' electromagnetic field energy intentionally or unintentionally, e.g. the antenna radiation excited beyond its resonance frequency. The voltage pattern is usually mapped on planar, cylindrical or spherical A sphere () is a geometrical object that is a three-dimensional analogue to a two-dimensional circle. A sphere is the set of points that are all at the same distance from a gi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Measurement System
A system of measurement is a collection of units of measurement and rules relating them to each other. Systems of measurement have historically been important, regulated and defined for the purposes of science and commerce. Systems of measurement in use include the International System of Units or (the modern form of the metric system), the British imperial system, and the United States customary system. History The French Revolution gave rise to the metric system, and this has spread around the world, replacing most customary units of measure. In most systems, length (distance), mass, and time are ''base quantities''. Later science developments showed that an electromagnetic quantity such as electric charge or electric current could be added to extend the set of base quantities. Gaussian units have only length, mass, and time as base quantities, with no separate electromagnetic dimension. Other quantities, such as power and speed, are derived from the base set: for example, spe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
