Abstract: A cavity oscillator comprising: an amplifier operable to provide energy to a local oscillating signal; a superconducting resonant cavity arranged to receive the local oscillating signal and being operable to reflect a portion of the local oscillating signal for use in a feedback circuit, to support an electromagnetic wave related to the local oscillating signal in a desired TM mode, and to output a filtered signal of a desired frequency or frequencies based on the geometry of the cavity; a feedback circuit operable to generate an error signal based on the local oscillating signal and the reflected signal; and a phase shifter arranged operable to adjust the filtered signal based on the error signal to generate an adjusted filtered signal. The amplifier can amplify the adjusted filtered signal.

Abstract: A reduced profile leaky-wave antenna and methods for manufacture therefor can include an inner conductor and an outer conductor. The outer conductor can be arranged in a coaxial relationship around the inner conductor to define an annular waveguide. A helical aperture can be formed in the outer conductor, to establish a leaky-wave antenna configuration. The helical aperture can have a helical pitch, which can be chosen according to the desired physical length of the antenna. For monopole reduced profile leaky-wave antennas, a metallic disk can optionally be placed the distal end of the antenna. For dipole reduced profile leaky-wave antenna embodiments, a metallic disk can be place at both ends of the antenna. The devices and methods of the present invention have the added advantage of allowing for the same feed structure to be used for both monopole antennas and dipole antennas.