Scanning a Linearly Polarized Wave Beam by Two Interacting Modes in a Multiwave Cherenkov Generator

Abstract

The possibility of producing a scanned linearly polarized wave beam by using a multiwave Cherenkov generator was studied theoretically and experimentally. As shown theoretically, two periodically alternating transverse modes with the same carrier frequency (9 GHz) can be generated by using azimuthally inhomogeneous periodic slow-wave structures. In the output waveguide, the mode field is essentially linearly polarized. Its transverse distribution is identical to the field distribution of the ТЕМ00 and ТЕМ10 modes in a confocal resonator. Theoretical calculations have shown that the angular position of the maximum in the radiation intensity distribution at a fixed distance from such a source varies from –9° to +9° with a period of 17–20 ns. The results of the experiment are in agreement with the theoretical predictions.