Development of a Double Octave Bandwidth Traveling-Wave Tube Amplifier

摘要

The purpose of this program is the attainment of lownoise amplification over two octaves in a single traveling-wave tube. Noise figure is to be less than 6 db from 2.0 to 8.0 Gc, with a minimum of ten milliwatts saturated power output. The work described in this report has been directed primarily at reducing noise figure to the 6 db specification, and at maintaining gain variation within the required = 3 db. The dependence of these performance characteristics on helix voltage has necessitated that effort be placed on design and fabrication of a glass support tubing for the helix, using low-loss type 7070 glass. The purpose is to render synchronous helix voltage essentially constant over the entire twooctave band. In the experimental tubes evaluated, the importance of cathode geometry in the achievement of broadband low-noise operation is demonstrated. (Author)