This paper presents the experimental study of microwave pulse compression using a five-fold helically corrugated waveguide. In the experiment, the maximum power compression ratio of 25.2 was achieved by compressing an input microwave pulse of 80-ns duration and 9.65-9.05-GHz frequency swept range into a 1.6-ns Gaussian-envelope pulse. For an average input power of 5.8 kW generated by a conventional traveling-wave tube, a peak pulse output power of 144.8 kW was measured corresponding to an energy efficiency of 66.3%.

The phenomenon of passive compression of frequency-modulated (FM) pulses in a dispersive media (DM) was used to increase the peak microwave power up to the multigigawatt level A helically corrugated waveguide was used as the DM, while a relativistic X-band backward-wave oscillator (RBWO) with a descending-during-the-pulse accelerating voltage served as a source of FM pulses Compression of pulses down to a halfwidth of 2 2 ns accompanied by a 4 5-fold power increase up to a value of about 3 2 GW has been demonstrated

The paper presents new results on the development of a method to generate ultrahigh-power short-microwave pulses by using a known principle of compression (reduction in pulse duration accompanying with increase in pulse amplitude) of a frequency-swept wave packet propagating through a dispersive medium. An oversized circular waveguide with helical-corrugations of its inner surface ensures an eigenwave with strongly frequency dependent group velocity far from cutoff. These dispersive properties in conjunction with high rf breakdown strength and low Ohmic losses make a helically corrugated waveguide attractive for increasing microwave peak power. The experiments performed at kilowatt power levels, demonstrate that an X-band microwave pulse of 80 ns duration with a 5% frequency sweep can be compressed into a 1.5 ns pulse having 25 times higher peak power by optimizing the frequency modulation of the input wave packet

Microwave pulse compression results from a five-fold helically corrugated waveguide are presented. In these experiments an X-band microwave pulse of duration 80 ns and a 6% frequency sweep was compressed from 5.8 kW to 128kW into a 1.6 ns pulse with a compression factor of 22 in the peak power