9 results about "Surface wave excitation" patented technology

A dual-resonant antenna device is provided, exhibiting improved impedance bandwidth, cross-polarization, and isolation, and is less susceptible to spurious surface wave excitation. More specifically, at least one antenna element and a resonant structure are provided on a non-conductive substrate, such that at least one continuous conductive sidewall of the resonant structure surrounds the one or more antenna elements, forming a resonant cavity filled with a dielectric material covering the one or more antenna elements. Each antenna element is used to excite a TM mode, while the dielectric material and size of the resonant cavity are selected such that the resonant structure is used to excite a TE mode. In a preferred embodiment, the TM mode is a TM 01 mode, and the TE mode is a TE 111 mode.

The invention provides a surface acoustic wave structure, a surface acoustic wave filter and communication equipment, and is characterized in that the lengths of at least part of first interdigital electrodes are set to be sequentially increased in the surface acoustic wave propagation direction, the increasing amplitudes are sequentially reduced, and the lengths of second interdigital electrodes are set to be sequentially reduced in the surface acoustic wave propagation direction; and the reduction amplitude is sequentially reduced, so that the excitation intensity of the surface acoustic waves of the interdigital transducer in each region in the surface acoustic wave propagation direction is non-linearly changed, and the excitation intensity is weakened in the region where a part of first interdigital electrodes arranged at the rear part in the surface acoustic wave propagation direction are located. The weakening can improve the near-band suppression capability of the surface acoustic wave filter, so that the resonant frequency burr phenomenon caused by transverse sound waves can be reduced or suppressed, namely, the resonant frequency splitting phenomenon is not easily caused. In addition, the surface acoustic wave structure provided by the invention does not need to be additionally provided with a structure for inhibiting a transverse mode, and is simple in preparation process, low in preparation cost and small in occupied area.

The invention discloses a nanopore transistor biomolecular sensor based on surface acoustic wave constraint and a preparation method thereof. The sensor comprises a substrate, a silicon nitride thin film layer, a detection layer, a first passivation layer covering the detection layer, a surface acoustic wave excitation structure arranged on the first passivation layer, a second passivation layer covering the surface acoustic wave excitation structure, a nanopore penetrating through the sensor, and a hydrophilic gate dielectric oxide layer covering the inner circumferential surface of the nanopore, which are stacked in sequence. The surface wave excitation structure is used for exciting a surface acoustic wave which is focused in a nanopore and generates a blocking effect on biomolecules, and comprises a piezoelectric film and an interdigital electrode layer arranged on the piezoelectric film. According to the invention, through the acoustic streaming effect of the acoustic surface wave, the charge induction of the transistor and the confinement effect of the nanopore, the broad-spectrum detection of various biomolecules can be realized without modifying a specific biological capture layer.

The invention discloses an electromagnetic ultrasonic surface wave multi-parameter synchronous detection sensor and a detection method, and the sensor comprises an electromagnetic ultrasonic surface wave excitation unit which is composed of a magnet group and a fold-back line type excitation ring. The two-dimensional component electromagnetic ultrasonic surface wave receiving unit consists of a magnet group, a vertical rectangular receiving coil and a horizontal runway type coil; the detection method comprises the following steps: the electromagnetic ultrasonic surface wave excitation unit excites an ultrasonic surface wave on the near surface of a detected object, and the ultrasonic surface wave generates an elliptically polarized wave with two-dimensional components of out-of-plane displacement and in-plane displacement and transmits the elliptically polarized wave forwards; a horizontal magnetic field and a vertical magnetic field are respectively cut below the two-dimensional component electromagnetic ultrasonic surface wave receiving unit and are respectively received by two coils of the receiving unit to form receiving signals of an out-of-plane component and an in-plane component; and the polarization coefficient, the wave velocity and the surface wave coefficient of the surface wave can be respectively obtained according to the two component signals and the distance between the excitation unit and the receiving unit, so that multi-parameter synchronous detection is realized.

The embodiment of the invention provides an excitation structure and a microwave oven, the excitation structure comprises a waveguide horn antenna and a surface wave generation assembly, and the waveguide horn antenna comprises a microwave transmission channel with a transmission inlet. The surface wave generation assembly comprises a seat body and a plurality of surface wave excitation structures, the seat body is provided with a surface wave generation cavity, the surface wave excitation structures are arranged in the surface wave generation cavity at intervals in the first direction, the two opposite ends of the surface wave generation cavity in the first direction are provided with a first communication port and a second communication port respectively, and the first communication port is communicated with the second communication port. And the microwave transmission channel is respectively communicated with the first communication port and the second communication port. The excitation structure provided by the embodiment of the invention can improve the heating uniformity.

The present invention discloses a method for modeling the path loss of indoor wireless channels based on surface wave excitation. First, a measurement scenario is set up, and according to the propagation characteristics of indoor high-frequency channels, an initial model of wireless channel path loss based on surface waves is constructed; the path loss exponent is extracted from the measurement data according to the initial model of wireless channel path loss, and the path loss exponent formula and the surface wave path loss attenuation formula are constructed by parameter extraction using the least squares method. Finally, an indoor high-frequency channel path loss model is constructed; the accuracy of the fitting curve and fitting parameters is verified by judging whether the coefficient of determination is greater than a preset threshold, and the mean and variance of the difference between the predicted value and the measured value are obtained using the statistical law of the cumulative distribution function of the shadow factor, and compared with the traditional path loss model to verify the accuracy of the model. Through this method, the characteristics of indoor channels can be understood more comprehensively and accurately, thereby improving the accuracy of channel measurement.

The application discloses a surface acoustic wave microfluidic acoustic tweezers device and method, and belongs to the technical field of microfluidics. Mainly includes: surface acoustic wave excitation module, application function module, impedance matching module, coupling agent. The surface acoustic wave excitation module is composed of an interdigital transducer and a piezoelectric wafer, and the application function module is composed of a separate working substrate or a working substrate with a microfluidic channel. The surface acoustic wave excitation module excites surface acoustic waves on the piezoelectric wafer, and excites Lamb waves in the application function module through the coupling agent, thereby realizing the arrangement, manipulation, sorting or mixing, centrifugation and other operations of microparticles or cells. In view of the problems that the existing surface acoustic wave microfluidic acoustic tweezers needs complex setting and is difficult to be reused, the device can use different module combinations according to different microfluidic application requirements, realize efficient excitation of surface acoustic waves in any direction in the microfluidic working area, and realize multifunctional and modular microfluidic acoustic tweezers application.

The invention discloses an optical fiber type laser ultrasonic measuring device and method suitable for a seawater high-pressure environment, and the device comprises a deep sea pressure tank part, and is characterized in that an optical fiber type laser ultrasonic system is arranged, a compression-resistant optical fiber is arranged in the optical fiber type laser ultrasonic system, and the compression-resistant optical fiber is located in the deep sea pressure tank part; an integrated receiving head is arranged at one end of the compression-resistant optical fiber and installed on a tank body of the deep sea pressure tank component to receive incident light, an ultrasonic surface wave excitation module of the laser ultrasonic system excites surface waves in a target area of a to-be-detected sample, and an ultrasonic detection module detects the excited surface waves. And processing the signal carrying the surface wave information to obtain the material property of the sample to be detected. The device realizes laser ultrasonic in-situ detection in the deep sea pressure ground simulation environment, and has the advantages of high time resolution, external vibration resistance, suitability for rough surfaces, suitability for the deep sea pressure environment and the like.

This invention discloses a surface wave antenna system integrated into a tilted vehicle windshield, comprising a stacked glass substrate, a parallel plate waveguide, a TEM surface wave excitation structure, a TM0 mode conversion and radiation structure, and a TE0 mode excitation and radiation structure. The TEM mode surface wave is shaped and propagated using a gradient-profile parallel plate waveguide, and TM0 mode conversion and leakage radiation are achieved at a single-sided ground interface. Simultaneously, the reverse current coupling between the upper and lower metal conductors excites large-angle TE0 mode surface wave propagation and radiation in the azimuth plane. This invention achieves wide-angle radiation coverage in both the elevation and azimuth planes, and requires no interconnecting vias, making it suitable for integration into vehicle windshields and application in high-frequency communication scenarios such as V2X.