Traveling wave tube-based linc transmitters

Adaptive Imbalances Correction in LINC Transmitters

Abstract: The LInear amplification using Nonlinear Components (LINC) technique is a wellknown power amplifier linearization method to reduce adjacent channel interference in a nonconstant envelope modulation system. Its major drawback is the inherited sensitivity to gain and phase imbalances between the two amplifier branches. In this paper two novel adaptive fulldigital base band methods are d...

Gain/Phase Imbalance-Minimization Techniques for LINC Transmitters

Two simple calibration schemes for the correction of the path imbalance in a linear amplification with nonlinear components (LINC) transmitter have been demonstrated. In the foreground algorithm, a baseband digital signal processor (DSP) evaluates the gain and phase imbalance with a set of calibration signals, while in the background algorithm, the imbalance is characterized by exchanging the t...

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...

Analysis of a traveling wave tube tuned by a cavity

We present a theoretical analysis of a system composed of two periodic structures separated by a uniform waveguide section, taking into consideration the impedance mismatch at both ends of the system. First we examine the effect of the reflections on.the output gain for a single stage system, i.e., when the uniform waveguide is not present. It is shown that if the product of the gain and the re...

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