40 results about "Microwave propagation" patented technology

Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Particular embodiments include clusters of small vias that effectively function as one large via, thereby increasing stop band bandwidth and maximizing parallel plate capacitance. Cluster vias can be configured to additionally provide a shielded and impedance matched route within the interior area of the cluster through which signal vias can connect transmission lines disposed in planes lying above and below the PPW. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.

A radar level gauge system comprising a transceiver for generating, transmitting and receiving electromagnetic signals; an antenna arranged to direct transmitted electromagnetic signals towards a surface of the product contained in the tank, and to return reflected electromagnetic signals resulting from reflections at impedance transitions encountered by the transmitted electromagnetic signals back to the transceiver; and a hollow waveguide connecting the transceiver and the antenna for guiding the electromagnetic signals therebetween. The radar level gauge system further comprises a leak indication member being movably arranged inside the hollow waveguide in such a way that a force resulting from leakage of the fluid at the sealing member causes a movement of the leak indication member which causes a change in at least one microwave propagation characteristic of the hollow waveguide.

A transmission line microwave apparatus includes at least one nonreciprocal transmission line part, which includes a series branch circuit equivalently including a capacitive element and a shunt branch circuit equivalently including an inductive element. The nonreciprocal transmission line part has gyrotropic characteristic by being magnetized in a magnetization direction different from the propagation direction of a microwave, and has an asymmetric structure to a plane formed by the propagation direction and the magnetization direction. The nonreciprocal transmission line part has a propagation constant and an operating frequency set in a dispersion curve that represents a relation between the propagation constant and the operating frequency so that the propagation constant in the forward direction and the propagation constant in the backward direction have nonreciprocal phase characteristics different from each other. A microwave transmission line is constituted by cascade-connecting at least one non-reciprocal transmission line part between first and second ports.

A novel method of fabrication of periodic dielectric composites involving a flexible computer design stage, rapid growth of a second dielectric component. Laser stereolithography is used to form the polymer material layer by layer by photopolymerisation of a liquid. Certain materials constructed in this fashion exhibit a complete loss-free barrier to microwave propagation through the material for a desired band of frequencies and are commonly known as photonic band gap crystals. Such materials could provide a novel medium for all-angle wide- and narrow-band blocking filters, narrow-band transmission filters, reflective and loss-free substrates for planar antennas, and novel loss-free media for oscillator cavities and waveguides. In addition a novel crystal structure, particularly suited to the fabrication method mentioned above and consisting of concatenated polyhedrons, is revealed.

Systems and methods are taught for blocking the propagation of electromagnetic waves in parallel-plate waveguide (PPW) structures. Periodic arrays of resonant vias are used to create broadband high frequency stop bands in the PPW, while permitting DC and low frequency waves to propagate. Some embodiments of resonant via arrays are mechanically balanced, which promotes improved manufacturability. Important applications include electromagnetic noise reduction in layered electronic devices such as circuit boards, ceramic modules, and semiconductor chips.

A plasma processing apparatus and a processing apparatus having a widened process condition range allowing plasma generation are obtained by increasing microwave propagation efficiency. The plasma processing apparatus includes a processing chamber where plasma processing is performed, and microwave introducer for introducing microwaves into the processing chamber. The microwave introducer includes a dielectric member transmitting the microwaves. The dielectric member has a shape in cross section in a direction approximately perpendicular to a transmitting direction of the microwaves through the dielectric member that allows transmission of the microwaves of substantially a single mode. The dielectric member has a thickness T in the transmitting direction that satisfies a condition of (λ×(2m+0.7) / 4)≦T≦(λ×(2m+1.3) / 4), where λ is a wavelength of the microwaves of the single mode transmitted through the dielectric member and m is an arbitrary integer.

The present invention relates to the field of propagation technology for microwave anechoic chamber isolation from the external environment, and in particular to a method for improving the performance of the quiet zone of the microwave anechoic chamber and a modular dielectric barrier. It is connected with a rectangular base, the acute angle of the right-angled triangle is 20-30°, the right-angled surface of the modular dielectric fence faces the electromagnetic radiation source, and the slope of the modular dielectric fence faces the center of the quiet zone; and the slope of the right-angled triangle is set There is a wave-absorbing material layer, and the wave-absorbing material layer is respectively arranged on the right-angled surface of the vertical surface of the right-angled triangle and the shielding body of the ground plane of the microwave anechoic chamber; the modularized dielectric barrier is fixed or movable. The invention uses multiple dielectric barriers to suppress ground reflection or wall reflection of the microwave anechoic chamber, which can reduce the size of the microwave anechoic chamber, directly reduce the construction cost of the microwave anechoic chamber, and further improve the quiet zone performance of the microwave anechoic chamber.

The invention relates to a liquid crystal microwave modulation device and a modulation method thereof. The device consists of n liquid crystal cells with the same structure and n channels of driving voltage signal sources A, n=2~10; the structure of the liquid crystal cell is as follows from top to bottom: the first glass substrate, the first ITO electrode, the first An alignment layer, a liquid crystal layer, a second alignment layer, a second ITO electrode, and a second glass substrate; wherein, spherical resin spacers are placed in the liquid crystal layer, and the n liquid crystal cells with the same structure are stacked sequentially from top to bottom , the n-channel drive voltage signal source A is composed of n mutually independent waveform signal generators, and each waveform signal generator is correspondingly connected to a liquid crystal cell. In the present invention, the dielectric constant of each layer of liquid crystal in the direction of microwave propagation can be changed according to the multi-channel driving voltage signals set by the user, and the results of outgoing microwave interference and diffraction can be adjusted.

A pipeline inner wall detection system and method provided in embodiments of the present invention relate to the technical field of pipeline inner wall detection. The method comprises that the vector network analyzer device outputs microwaves and transmits the microwaves to the coaxial feeding end cover device; the coaxial feeding end cover device transmits the received microwaves into the pipeline to be tested, and when there is a When thinning, receive the echo signal reflected back by the thinning part of the inner wall of the pipe to be tested in the microwave; then the coaxial feeding end cover device will also transmit the received echo signal to the vector network analyzer device; the vector network The analyzer device also processes the echo signals to obtain thinning information at the thinning of the inner wall of the pipe under test. The wave impedance changes at the thinned part of the inner wall of the pipeline to be tested through microwaves, resulting in impedance mismatch, which causes the microwave to reflect at the thinned part in the time domain, and then processes the reflected echo signal to obtain the measured Thinning information at the thinning of the inner wall of the pipe. Improve detection accuracy.

A fill-level measuring device for ascertaining and monitoring fill level of a medium located in the process space of a container by means of a microwave travel time measuring method. The device comprises a measurement transmitter and an antenna unit, which is constructed at least of a hollow conductor and a radiating element A microwave transmissive, process isolating element is inserted for process isolation into the hollow conductor between the measurement transmitter and the horn shaped radiating element contacting the process space. The process isolating element is embodied as a hollow body having at least one tubular hollow body region matched to the shape of the hollow conductor, and a pointed hollow body region neighboring the hollow body region in the direction of the radiating element and having a wall thickness selected based on reflection, or lack thereof, of the microwave signals.

The microwave plasma generator is applied to transmission of electromagnetic field into plasma. The invention consists of the fact that the guiding part (3) has two outputs (4, 4′) between which an input (2) of microwave is placed generated from the microwave power source (5). The input (2) is in the distance (A) from the separation (10) of the first output (4) and in the distance (B) from the separation (10′) of the second output (4′) while the absolute value of the difference of the distances A-B or B-A equals λ / 2 where λ is the wave length of the microwave and distances A and B correspond to the trajectory of microwave propagation. A microwave plasma generator including microwave power source (magnetron) (5) is connected to the input (2) of the guiding part (3) of the applicator (1).