학술논문

Coherent Power Combination in a Resonant-Tunneling-Diode Arrayed Oscillator With Simplified Structure
Document Type
Periodical
Source
IEEE Transactions on Terahertz Science and Technology IEEE Trans. THz Sci. Technol. Terahertz Science and Technology, IEEE Transactions on. 13(4):405-414 Jul, 2023
Subject
Fields, Waves and Electromagnetics
Oscillators
Antenna arrays
Power generation
Resistors
Slot antennas
Eigenvalues and eigenfunctions
Voltage
Arrayed oscillator
power combination
resonant tunneling diode (RTD)
Language
ISSN
2156-342X
2156-3446
Abstract
Coherent resonant-tunneling-diode (RTD) oscillator array is promising for high-power terahertz sources. However, it is complicated to identify the proper operation mode in an arrayed RTD oscillator. Here, we established a simple and general analytical method for operation modes in RTD arrayed oscillators. We also proposed and fabricated a terahertz slot antenna integrated RTD oscillator array coupled by a resistor for stable operation and coherent power combining. From the analysis for the resistor-coupled oscillator array, we found that the odd-mode operation, where adjacent oscillators operate in antiphase condition, is stable. Hence, we proposed an arrayed structure with a right-angle connection between adjacent oscillators for coherent power combination and validation of operation mode. In preliminary experiments, we successfully fabricated two-element resistor-coupled arrayed oscillators. Output power and oscillation spectrum measurements showed that coherent power combination was achieved in arrayed oscillators. The odd-mode operation was validated by polarization measurements. Relatively high output powers of ∼770 μW were obtained at 530 GHz in two-element arrayed oscillators with offset-fed slot antennas.