A k-band broadband monolithic distributed frequency multiplier based on nonlinear transmission line

A fabrication technology of GaAs planar Schottky varactor diode (PSVD) is successfully developed and used to design and manufacture GaAs-based monolithic frequency multiplication based on 23-section nonlinear transmission lines (NLTLs) consisting of a coplanar waveguide transmission line and periodically distributed PSVDs. The throughout design and optimization procedure of 23-section monolithic NLTLs for frequency multiplication in the k-band range is based on a large signal equivalent model of PSVD extracted from small-signal S-parameter measurements. This paper reports that the distributed SPVD exhibits a capacitance ratio of 5.4, a normalized capacitance of 0.86 fF/μ² and a breakdown voltage in excess of 22 V. The integrated 23-section NLTLs fed by 20-dBm input power demonstrates a 26-GHz peak second harmonic output power of 14-dBm with 25.3% conversion efficiency in the second harmonic output frequency range of 6 GHz-26 GHz.