Compression of Frequency-Modulated Pulses using Helically Corrugated Waveguides and Its Potential for Generating Multigigawatt rf Radiation

A new method to generate ultrahigh-power microwave pulses compatible with mildly relativistic electron sources is proposed. This method involves a novel microwave compressor in the form of a metal helically corrugated waveguide, which can enhance the power of frequency-modulated nanosecond pulses up to the multigigawatt level. The results of the proof-of-principle experiments at kilowatt power levels are in good agreement with theory.

Figure 1

Contours of maximum power compression ratio (solid lines) and optimum length (dashed lines) for a circular copper waveguide 19.2 mm in diameter.

Figure 2

(a) Dispersion diagram for the operating helically corrugated waveguide (b) group velocity derived from the curves in (a) and losses (in dB) for a 2.08 m long waveguide as functions of frequency.

Figure 3

Experimental setup.

Figure 4

Pulse compression in the circular waveguide: (a) experimental results; (b) simulation results.

Figure 5

Pulse compression in the helically corrugated waveguide: (a) experimental results; (b) simulation results.