A Ka-Band GaN-on-Si MMIC Analog Vectorial Modulator and Its Broadband Calibration Procedure

This letter introduces for the first time a fully integrated analog vectorial modulator (VM) in gallium nitride on silicon (GaN-on-Si) monolithic microwave-integrated circuit (MMIC) technology, operating in $Ka$ -band, and an analytical calibration technique suitable for VM. An extensive characterization of the prototype, with both static and dynamic modulating signals, validates both the design and the calibration technique. The VM is capable to produce corrected constellations with accuracy of 0.06 dB and 0.28° root mean square, respectively, for amplitude and phase, across the 35–40 GHz bandwidth. Furthermore, it is capable to generate single-side modulated signal with undesired sideband suppression in excess of 47 dBc.