Theoretical Investigation of Harmonic Gyrotron Traveling Wave Tube Amplifier with High Efficiency, Power, Gain, and Broadband Capabilities

• Main Authors: Shun-Chiao Chang, 張舜喬
• Other Authors: Kwo-Ray Chu
• Format: Others
• Language: en_US
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/93298456062534524967

碩士 === 國立臺灣大學 === 物理研究所 === 100 === High power and broad-band gyrotron traveling wave tube amplifier (gyro-TWT) is employed in satellite communication and millimeter-wave radar which provides higher resolution and penetrates deeper under foggy and smoky conditions in Ka-band that covers the frequency of 26.5-40 GHz. As is well known, the efficiency so as to power capability of gyro-TWT in second harmonic operation was significantly restricted by harmonic cyclotron interaction strength and inherent nonlinear effect. Beginning from the study of convective instability, TE11 mode, distributed-loss gyro-TWT which features the ultra-high gain and broad-band operation, the high efficiency as well as high power second harmonic gyro-TWT could be achieved by enhancement of harmonic cyclotron interaction. The simulation work indicate that the method profoundly strengthen the performance of saturated efficiency as well as saturated power for second harmonic gyro-TWT. The results provide a remedy of efficiency for second harmonic operation which favors less magnetic-field requirement.