Abstract:
A coupled cavity circuit for a microwave electron tube comprises at least two resonant cavities adjacent to each other. An electron beam tunnel passes through the coupled cavity circuit to allow a beam of electrons to pass through and interact with the electromagnetic energy in the cavities. An iris connecting the adjacent cavities allows electromagnetic energy to flow from one cavity to the next. The iris is shaped to cause the iris mode passband to be lower in frequency than the cavity mode passband while still providing broadband frequency response. In addition, the present coupled cavity circuit operates on an electron beam to interact with the third space harmonic of the second passband (the cavity passband) of the electromagnetic signal. Preferably, this interaction occurs on the second passband as this operational design provides output with higher frequencies without decreasing the cavity size. Furthermore, this operational design provides more frequencies with no increase to the iris size. This results in allowing higher power to be provided to the circuit without thermal degradation of the circuit. Also, because the interaction occurs on the third space harmonic of the second passband, the present operational design results in providing flatter frequency responses.
Abstract:
The thickness of the fingers of the line is modified, while the pitch of the fingers is kept constant, so that the capacitance between two successive fingers varies substantially proportionally to the product P.sub.HF .times.dI/dx, in which P.sub.HF represents the microwave power at any point x in the line and dI/dx the gradient, as a function of the position x on the line, of the current I delivered by the voltage supply creating a continuous electrical field E.sub.o between the electrodes of the tube. The values of P.sub.HF and of I are measured on the tube having a constant coupling resistance or are calculated by a computer program.
Abstract:
A microwave oscillator is provided having electron emissive means and a first surrounding resonant structure. The first structure is fabricated of a material capable of emitting secondary electrons. A second resonant structure surrounds the secondary electron emitter and microwave energy is generated by the interaction between the electrons and currents induced in the structure. The high degree of isolation between the first oscillator section and the second amplifying section results in the generation of stable oscillations relatively free of effects of load variations.