Abstract: A radio repeater wherein a reflective negative resistance amplifier, using the negative resistance of a Gunn diode, is applied at one side of a dielectric waveguide, enabling signals to be inputted through the input terminal dielectric waveguide, circulated in the circulator and enter the Gunn diode. Reflected waves amplified in the Gu diode exit the output terminal dielectric waveguide. A radio repeater is provided on the non-radiative dielectric waveguides using the multi-space non-radiative dielectric waveguides, which receives a frequency, amplifies it, and retransmits the amplified signals to any direction. With a dielectric band inserted in the radio repeater, directions for reception and transmission can be freely changed. Using the radio repeater, a small size radio repeater of low power consumption may be made.

Abstract: A circuit with non-radiative dielectric waveguides held between two parallel metal plates which are multi-layered. Since the circuit has different heights of spacers between the plates owing to multiple layers, different sizes of non-radiative dielectric waveguides that are designed according to their using frequencies, are all inserted into a single circuit. By use of the present invention, we are capable of constructing a super-heterodyne receiver, which has the characteristic of mixing received waves through a local oscillator to produce an intermediate frequency. With the intermediate frequency, it is a lot easier to enhance amplitude and consequently reception sensitivity is improved.

Abstract: A high frequency amplifier with the multi-space structure, amplifying various frequencies by a Gunn diode in the multi-space structure, composed of non-radiative dielectric waveguides of various different sizes. An amplifier circuit includes a Gunn diode inserted in a space between two metal plates of a certain distance from each other, a circulator which revolves input waves and determines transmission direction, a first non-radiative dielectric waveguide, which is connected to the circulator, sending the input waves from the input terminal to the circulator, a second non-radiative dielectric waveguide, which is connected to the circulator, sending the input signals from the circulator to the Gunn diode and sends the amplified signals from the Gunn diode back to the circulator; and a third non-radiative dielectric waveguide, which is connected to the circulator, sending the amplified signals, which come into the circulator through the second non-radiative dielectric waveguide, to the output terminal.

Abstract: The present invention relates to an oscillator with the multi-layer non-radiative dielectric waveguide structure, which is able to generate various frequencies through oscillator elements and resonators, built in a multi-space structure with non-radiative dielectric waveguides of different sizes. Because it would not be necessary to construct many different packages in order to generate various frequencies, the present invention has an economical advantage.