Improved design of an ultra-broadband probe for multiprobe reflectometers

A novel design of the probe intended for application in multiprobe reflectometer is proposed. It is realized as a connection of short weakly-coupled-line sections and a lumped resistor and provides flat coupling characteristics over a very wide frequency range. The developed probe has been utilized in the design of a multiprobe reflectometer operating within the bandwidth 0.15-8 GHz. The measurements of reflection coefficients of exemplary reflective elements performed with the use of the developed measuring system confirm the improved performance of the proposed solution.