The parameter most commonly measured by a slotted line is SWR . This serves as a measure of the accuracy of the impedance match to the item under test.
12.
Slotted lines can measure standing waves, wavelength, and, with some calculation or plotting on Smith charts, a number of other parameters including reflection coefficient and electrical impedance.
13.
A slotted line involves a waveguide ( or air-filled coaxial line ) in which a small sensing antenna measures the electric field along the transmission line " directly ".
14.
This is done on a slotted line by measuring the distance of the first minimum from the DUT . Moving the probe right up to the DUT is not practicable so a different approach is usually adopted.
15.
The most intuitive method uses a slotted line which is a section of transmission line with an open slot which allows a probe to detect the actual voltage at various points along the line . Thus the maximum and minimum values can be compared directly.
