The concepts of in-phase multichannel Ka-band HPM oscillators

Summary form only given. The prospects of development of in-phase Ka-band HPM oscillators based on relativistic BWOs without electrodynamic coupling are considered. Efficient RF power summation is possible if the phase spread in each channel will be at least ten times less than the period of carrier microwave frequency. Two approaches on construction of parallel, in-phased relativistic BWOs are compared. The system involving two independent high voltage PDFL generators with a gas discharge switches triggered by splitting electron beam appears to be not profitable energetically as compare to the version where electron injectors of two BWOs are supplied by splitting pulse from a single, more powerful high-voltage generator. For the last option it has been demonstrated already that mutual stability of current fronts of parallel e-beams attains units of picoseconds. This fact we used earlier in the experiments with two X-band BWOs where phasing spread of microwave pulses did not exceed 2 ps. Report presents future options of similar experimental Ka-band devices being under development now. In capacity of high-voltage sources, the RADAN-type generators with integrated stabilized gas spark gap and SOS modulator added with semiconductor-diode-based or gas discharge pulse sharpener will be applied. We plan to demonstrate a deterioration of accelerating pulses delivered to the e-beam diodes, stability of the microwave power envelop of a single-channel multi-megawatt Ka-band BWO, and results of other preparatory test and calibration measurements.