Dual-Channel Frequency Source With Distributable Channel Power Based on Mode Control

Traditional frequency multipliers typically feature single-channel input and output designs, primarily serving as local oscillators in mixers or signal sources in point-to-point transmission systems. However, these designs offer limited versatility, particularly in applications requiring dynamic power distribution across multiple directions. To address this limitation, we introduce a novel dual-channel frequency doubler based on GaAs monolithic integrated technology that allows for adjustable power distribution between two output channels. The design incorporates a vertically aligned, multistage waveguide that couples power into two parallel rows of diodes. By exploiting the nonlinear characteristics of these diodes, the device efficiently generates second harmonics across both channels. Moreover, the coupling ratio of input power between the two channels can be dynamically controlled by adjusting the bias applied to the diodes. Across 155–170 GHz frequency range, the device achieved a maximum output power of 69.9 mW and a peak conversion efficiency of 29% with both channels active. With only one channel active, the maximum output power reached 71.7 mW, and the peak conversion efficiency was 23.8%. This prototype effectively demonstrates the feasibility of our approach and establishes a solid foundation for future expansion into the terahertz frequency range.

I. Introduction

Frequency multipliers, as an essential component in terahertz application systems, contribute significantly to earth atmospheric sensing, radio astronomy, space astrophysics, imaging, and high-speed communication. It has been the focus of research worldwide, with a quest for high power, wide bandwidth, and high conversion efficiency [1], [2], [3], [4], [5], [6].