Novel broadband coupler for detection of RF signals in microwave systems

This paper reports the results of a novel miniature broadband resistive coupler for detecting RF signals. The design presented here is a unique implementation of a resistive (Wheatstone type) bridge coupler operating over a frequency range of 2 to 18 GHz. The coupler was integrated with diode detectors and used in an extended range digital log video amplifier to provide excellent performance. When fabricated in standard MIC technology it occupies an area of less than 1.6 mm₂. The couplers design is also suitable for realization using MMIC technology.