60-GHz Near-Field Six-Port Microscope Using a Scanning Slit Probe for Subsurface Sensing

A new six-port based near-field millimeter-wave microscope using a scanning slit probe is proposed for subsurface sensing applications. The combination of a six-port reflectometer and a slit probe presents a viable and promising alternative to the costly heterodyne principle. The system presents advantages such as compactness, robustness, and low cost. To evaluate its performance, the spatial resolution is experimentally verified.