A new interferometric sensor for scanning near-field microwave microscopy

Abstract

A new microstrip sensor using the transmission interferometric measurement principle for scanning near-field microwave microscopy is presented. The structure originates from a Wilkinson power divider but has a resistor removed. The wideband design was verified by simulation using AWR Microwave Office and experimentally in frequency band of 45 MHz to 20 GHz. Ten times suppression of measurement uncertainties due to noise of a vector network analyzer was achieved. The structure is simple, cheap and mechanically stable with no moveable part.