On the Physics of Harmonic Injection in a Traveling Wave Tube

Experimental verification of the mechanisms for nonlinear harmonic growth and suppression by harmonic injection in a traveling wave tube.

Understanding the generation and growth of nonlinear harmonic (and intermodulation) distortion in microwave amplifiers such as traveling wave tubes (TWTs), free electron lasers (FELs), and klystrons is of current research interest. Similar to FELs, the nonlinear harmonic growth rate scales with the harmonic number in TWTs. In klystrons, the wave number scaling applies to the nonlinear harmonic ...

Second Harmonic Reduction of Traveling Wave Tube Amplifier Using Ferrite Material

Traveling Wave Tubes (TWTs) consist of different elements. The most important element of TWT is the RF circuit. RF circuits in helix TWTs need a dielectric support to hold the helix; this support also has an effect in electromagnetic properties of RF circuits. A novel dielectric support is proposed to reduce the second harmonic of helix TWTs. The dielectric support in this structure consists of...

Multi-megawatt Relativistic Harmonic Gyrotron Traveling-Wave Tube Amplifier Experiments

Operation of a Large-Orbit High-Harmonic Gyro-Traveling-Wave Tube Amplifier

Absfracf-The high-harmonic gyro-traveling wave tube (gyro-TWT) is a high-power ( 2 1 kW) millimeter wave amplifier based on the synchronous interaction of a beam of lafge-orbit axis-encircling electrons with a high-order cylindrical waveguide mode. Since the interaction occurs at a high harmonic of the cyclotron frequency, the intense magnetic fields required for the conventional fundamental-mo...

focus on communication in iranian high school language classes: a study of the role of teaching materials in changing the focus onto communication in language classes

چکیده ارتباط در کلاس به عوامل زیادی از جمله معلمان، دانش آموزان، برنامه های درسی و از همه مهم تر، مواد آموزشی وابسته است. در تدریس ارتباطی زبان که تاکید زیادی بر توانش ارتباطی دارد، کتاب درسی به عنوان عامل موثر بر پویایی کلاس محسوب میگردد که درس ها را از طریق فراهم آوردن متن ارتباط کلاسی و هم چنین نوع تمرین زبانی که دانش آموزان در طول فعالیت های کلاسی به آن مشغول اند، کنترل می کند. این حقیقت ک...