A High-Resolution Swept-Frequency Reflectometer

A simple swept-frequency reflectometer is described that is capable of measuring reflection coefficients as low as 0.001 and is particularly suitable for precise impedance matching. With the exception of a length of accurate plain waveguide, used as a standard, the instrument contains no critical components and requires no tuning adjustments. The reflection coefficient is displayed on an oscilloscope or X-Y recorder on an almost linear scale that is only slightly affected by departures from square-law detection.