Wide Bandwidth Frequency Tripler Based on Composite Right/Left-Handed Transmission Lines with Embedded Back-to-Back Schottky Diodes

This work presents a high-performance W-band (75-110 GHz) frequency tripler, featuring a combination of back-to-back Schottky diodes and composite right/left-handed transmission lines (CRLH TLs). The tripler was monolithically fabricated on GaAs substrate for the first time. The back-to-back Schottky diodes, which are designed only to generate odd harmonics, simplify the design of the tripler. The CRLH TLs have a balanced structure and a high-pass frequency response. The fabricated tripler has a maximum output power of 9.8 mW at the third harmonic of 99 GHz, a corresponding conversion loss of 15 dB, and a maximum 3-dB bandwidth of 20.2%.