Abstract: An isolated dual-mode converter includes a TE01 mode converter including a circular waveguide, and a plurality of rectangular waveguides connected to the circumference of the circular waveguide; and a TM01 mode converter including a coaxial waveguide, formed by coaxial outer and inner conductors, and the circular waveguide connected and aligned axially with the coaxial waveguide, wherein a symmetrical axis of an opening at the end of the rectangular waveguides connected to the circular waveguide is parallel to the axis of the circular waveguide, thereby avoiding interfering with the propagation of TM01 mode. In an application, the isolated dual-mode converter outputs TE01 mode and TM01 mode at the same port, thereby achieving more uniform microwave heating. In another application, two isolated dual-mode converters are aligned face-to-face, forming a dual-channel joint with high channel isolation and low transmission loss, which may be used for a rotary joint of a radar system.

Abstract: A microwave rotary joint comprises a mode converter for converting microwave signals of a TE01 circular symmetric mode, and the mode converter comprises: two circular waveguides, one end of each of the waveguides has a circular input/output port; and two power dividing structures, each of the power dividing structure has an input/output port and four connecting ports, the four connecting ports are separated and surround each of the circular waveguides and connected to the inside of each of the circular waveguides, the two circular waveguides are integrated as one member through rotating a bearing.

Abstract: The invention discloses a microwave supplying apparatus including a microwave generator, a first power divider, a second power divider, a first waveguide, and a second wave guide. The first waveguide is connected to the microwave generator and has a first output terminal and a second output terminal to divide a microwave generated by the microwave generator along a first direction. The second power divider is connected to the first output terminal and has a third output terminal and a fourth output terminal to divide the microwave along a second direction. The first waveguide and the second waveguide are connected to the third output terminal and the fourth terminal respectively and receive the microwave through the first power divider and the second power divider to respectively output the microwave fields with approximate intensity distributions.

Abstract: A mode-selective interactive structure for gyrotrons includes a plurality of metal tubes, wherein an inner wall of each metal tube forms a waveguide; and between each adjacent pair of the metal tubes exists a slice with a first interface and a second interface and when an electromagnetic wave comprising an operating mode and a competing mode propagates through the slice, the competing mode is partially reflected upon, partially transmitted through and/or absorbed at the first interface and the second interface of the slice so that the power loss of the competing mode is larger than the operating mode and the production of the competing modes is suppressed progressively thereby achieving mode selection.

Abstract: A microwave rotary joint comprises a mode converter for converting microwave signals of a TE01 circular symmetric mode, and the mode converter comprises: two circular waveguides, one end of each of the waveguides has a circular input/output port; and two power dividing structures, each of the power dividing structure has an input/output port and four connecting ports, the four connecting ports are separated and surround each of the circular waveguides and connected to the inside of each of the circular waveguides, the two circular waveguides are integrated as one member through rotating a bearing.

Abstract: The a polarized high-order mode electromagnetic wave converter and its coupling method, uses bifurcate structure to divide the input wave into two signals with the same amplitude but opposition phases, which are then inputted into a circular main waveguide through waveguide so that the input wave could convert into linearly polarized high-order mode in the main waveguide, and then undergo the polarization change conversion stage to convert the polarized wave into circularly polarized wave. The coupling method includes the electromagnetic wave bifurcate stage, mode conversion stage, and may combine with a polarization conversion stage. The TE21 coupler is tested with simulation computation and fabricated, and proved to product consistent results with the computer simulation. The coupler has features of high conversion efficiency, high mode purity, wide bandwidth, polarity control, and convenience in processing.

Abstract: A quasi-optical material treatment apparatus includes a first mirror and a second mirror. The first mirror is arched, and has a focal point in a chamber distance, and a coupling port to receive a high power microwave from an external microwave source that travels along the chamber distance to output a strong field microwave beam. The second mirror and the first mirror jointly form a quasi-optical action chamber and are movable relative to each other to adjust the total chamber distance between the two. A material to be treated may be moved through a focusing zone (about one wavelength of the strong field microwave beam) of the strong field microwave beam to be treated rapidly and evenly.

Abstract: The high order mode electromagnetic wave coupler and coupling method uses one or more Y-shaped bifurcated waveguides to divide the wave to one or more order, so as to divide the target electromagnetic wave proportionally into equal shares. The waveguide is used to inject the electromagnetic wave to a main waveguide, so that the electromagnetic wave is converted into high order mode in the main waveguide. For example, a rectangular waveguide TE10 mode can be converted to a circular TE01 mode, wherein this conversion can also be applied to higher order modes and microwave guide-shaped modes. The coupling method includes a electromagnetic wave power dividing section and mode converting section, of which the power divider and dividing method can divide the electromagnetic wave proportionally. The coupler and coupling method feature high converting efficiency, high mode purity, high bandwidth, and convenient operation.

Abstract: The high order mode electromagnetic wave coupler and coupling method uses one or more Y-shaped bifurcated waveguides to divide the wave to one or more order, so as to divide the target electromagnetic wave proportionally into equal shares. The waveguide is used to inject the electromagnetic wave to a main waveguide, so that the electromagnetic wave is converted into high order mode in the main waveguide. For example, a rectangular waveguide TE10 mode can be converted to a circular TE01 mode, wherein this conversion can also be applied to higher order modes and microwave guide-shaped modes. The coupling method includes a electromagnetic wave power dividing section and mode converting section, of which the power divider and dividing method can divide the electromagnetic wave proportionally. The coupler and coupling method feature high converting efficiency, high mode purity, high bandwidth, and convenient operation.

Abstract: The a polarized high-order mode electromagnetic wave converter and its coupling method uses bifurcate structure to divide the input wave into two signals with the same amplitude but opposition phases, which are then inputted into a circular main waveguide through waveguide so that the input wave could convert into linearly polarized high-order mode in the main waveguide, and then undergo the polarization change conversion stage to convert the polarized wave into circularly polarized wave. The coupling method includes the electromagnetic wave bifurcate stage, mode conversion stage, and may combine with a polarization conversion stage. The TE21 coupler is tested with simulation computation and fabricated, and proved to produce consistent results with the computer simulation. The coupler has features of high conversion efficiency, high mode purity, wide bandwidth, polarity control, and convenience in processing.

Abstract: Voltage fluctuations, especially due to a resonant effect of a power distribution system, result in serious timing skews in a high-speed digital system. Adding extra resistive loadings for coupling out the noise into external terminations will reduce a quality factor of the power distribution system, which will effectively minimize the noise accumulation. The external coupled resistive terminators are preferably formed on positions of a microstrip resonator where relatively high noise fluctuations occur. Each of the external coupled resistive terminators may be formed of a resistor, a transmission line with a resistor at one end, a lossy transmission line with an open circuit at one end, or a quarter-wavelength lossy transmission line. Simulation results indicate that the maximum voltage fluctuations are suppressed from 750 mV to 150 mV at a resonant frequency and about 50% for an overall range of the operating frequencies.

Abstract: A quasi-optical material treatment apparatus includes a first mirror and a second mirror. The first mirror is arched, and has a focal point in a chamber distance, and a coupling port to receive a high power microwave from an external microwave source that travels along the chamber distance to output a strong field microwave beam. The second mirror and the first mirror jointly form a quasi-optical action chamber and are movable relative to each other to adjust the total chamber distance between the two. A material to be treated may be moved through a focusing zone (about one wavelength of the strong field microwave beam) of the strong field microwave beam to be treated rapidly and evenly.

Abstract: An approach to enhance the noise immunity of high-speed digital signals by means of a resonance-free environment is developed. Resonance detuning is achieved by appropriately reshaping the layout of the power/ground planes. Resonant properties of the power distribution system, including resonant frequencies and field distribution profiles, were characterized with frequency-domain simulations. Analysis of the resonant field profiles reveals that the electric field distribution of the dominant mode normally concentrates in the vicinity of the plane edge. Therefore, resonance can be effectively tuned out of the operating frequency range through boundary configuring. In addition, it is shown that variation of the quality factor with the external probe position provides a means to monitor and construct the resonant field distribution. Physical mechanism responsible for this unique property is clarified from the perspective of probe coupling.

Abstract: Voltage fluctuations, especially due to a resonant effect of a power distribution system, result in serious timing skews in a high-speed digital system. Adding extra resistive loadings for coupling out the noise into external terminations will reduce a quality factor of the power distribution system, which will effectively minimize the noise accumulation. The external coupled resistive terminators are preferably formed on positions of a microstrip resonator where relatively high noise fluctuations occur. Each of the external coupled resistive terminators may be formed of a resistor, a transmission line with a resistor at one end, a lossy transmission line with an open circuit at one end, or a quarter-wavelength lossy transmission line. Simulation results indicate that the maximum voltage fluctuations are suppressed from 750 mV to 150 mV at a resonant frequency and about 50% for an overall range of the operating frequencies.

Abstract: An approach to enhance the noise immunity of high-speed digital signals by means of a resonance-free environment is developed. Resonance detuning is achieved by appropriately reshaping the layout of the power/ground planes. Resonant properties of the power distribution system, including resonant frequencies and field distribution profiles, were characterized with frequency-domain simulations. Analysis of the resonant field profiles reveals that the electric field distribution of the dominant mode normally concentrates in the vicinity of the plane edge. Therefore, resonance can be effectively tuned out of the operating frequency range through boundary configuring. In addition, it is shown that variation of the quality factor with the external probe position provides a means to monitor and construct the resonant field distribution. Physical mechanism responsible for this unique property is clarified from the perspective of probe coupling.