9 results about "Notch band" patented technology

Techniques for improving acoustic wave device structures are disclosed, including filters and systems that may include such devices. An apparatus may comprise a first electrical filter including an acoustic wave device. The first electrical may having a first filter band in a Super High Frequency (SHF) band or an Extremely High Frequency (EHF) band to facilitate compliance with a regulatory requirement or a standards setting organization specification. For example, the first electrical filter may comprise a notch filter having a notch band overlapping at least a portion of an Earth Exploration Satellite Service (EESS) band to facilitate compliance with a regulatory requirement or the standards setting organization specification for the Earth Exploration Satellite Service (EESS) band.

This application discloses a grid-connected inverter control method based on a notch filter phase-locked loop (PLL) for weak grid conditions. The method first designs a notch filter with adjustable notch depth and bandwidth, setting its notch frequency to the grid power frequency. It then acquires the three-phase voltage at the grid connection point, subtracts the voltage after notching, and extracts the power frequency component of the three-phase voltage. The power frequency component is phase-locked in a synchronous reference frame to obtain the modulation wave phase signal. The inverter output voltage and current are acquired, and active and reactive power are calculated. A dual closed-loop control circuit with an outer power loop and an inner current loop is constructed, outputting the modulation wave voltage amplitude signal. Finally, the modulation wave phase signal and amplitude signal are combined to generate a pulse modulation wave signal. Thus, this invention can accurately lock the grid phase when the weak grid voltage contains harmonics and DC components, effectively improving the stable grid-connected operation capability of the grid-connected inverter under large disturbances.

This application relates to the field of electronic manufacturing technology, specifically to a method and system for detecting alignment errors in a film coating process. The method includes: acquiring a grayscale image of a coated substrate and a local film thickness gradient along the substrate transport direction; determining the center frequency and notch bandwidth of interference fringes in the image frequency domain based on the local film thickness gradient, and filtering the spectrum of the grayscale image of the coated substrate according to the center frequency and the notch bandwidth to obtain a cleaned image; extracting the gradient amplitude of the cleaned image within the region of interest of a marked point, and determining a calculation window based on the statistical characteristics of the gradient amplitude, calculating the sub-pixel center coordinates of the marked point within the calculation window; performing error calculation based on the sub-pixel center coordinates, and verifying the result by combining a preset alignment tolerance, thereby obtaining the alignment error detection result. This application can adaptively separate interference frequency components and achieve accurate detection and correction of alignment errors.

A light-filtering layer is provided that comprises a polymer substrate and at least three absorbing compounds combined with the polymer substrate, wherein the absorbing compounds each absorb light in a notch band having a full-width half maximum of no more than 40 nm. In some examples, the absorbing compounds can be provided in combination so that, for light produced by a display screen that is transmitted through the light-filtering layer, the correlated color temperature is within 1000 Kelvin of the correlated color temperature for light produced by the display screen that is not transmitted through the light-filtering layer. Peak absorptions for the first, second, and third absorbing compounds can be between 436 nm and 522 nm, 548 nm and 616 nm, and 643 nm and 730 nm, respectively. In some embodiments, a fourth absorbing compound can be provided in combination with the polymer substrate and absorbing compounds and can have peak absorption between 417 nm and 465 nm.

The present invention is a multi-absorption band ultra-wideband non-reflection notch antenna, the antenna comprising a dielectric substrate (1), a microstrip line (2), a transition structure (3), a resistor-inductor branch (4), a Vivaldi antenna (5) and a folded dipole (6); the transition structure realizes broadband matching from the microstrip line to the Vivaldi antenna; the resistor-inductor branch connected in parallel realizes absorption of low-frequency echo reflection of the antenna to form a low-frequency absorption band; the folded dipole is distributed between two antenna arms of the Vivaldi antenna to realize an absorption band without reflection notch within the working frequency band. The ultra-wideband end-fire antenna has multiple absorption bands, absorbs notch frequency bands and low-frequency echo reflections, reduces the influence of echo reflections on the overall performance of the system, such as reducing the nonlinear distortion caused by echo reflections, and reducing the influence of reflections on the stability of the pre-amplifier.

A light-filtering layer is provided that comprises a polymer substrate and at least three absorbing compounds combined with the polymer substrate, wherein the absorbing compounds each absorb light in a notch band having a full-width half maximum of no more than 40nm. In some examples, the absorbing compounds can be provided in combination so that, for light produced by a display screen that is transmitted through the light-filtering layer, the correlated color temperature is within 1000 Kelvin of the correlated color temperature for light produced by the display screen that is not transmitted through the light-filtering layer. Peak absorptions for the first, second, and third absorbing compounds can be between 436nm and 522nm, 548nm and 616nm, and 643nm and 730nm, respectively. In some embodiments, a fourth absorbing compound can be provided in combination with the polymer substrate and absorbing compounds and can have peak absorption between 417nm and 465nm.

The present invention relates to a three-radiation zero-point coplanar waveguide dual-polarization notch cross-dipole antenna, comprising a dielectric substrate, a metal reflector and two coaxial cables, wherein the cross-dipole antenna is printed on the upper and lower layers of the substrate and fed by the two coaxial cables, and the metal reflector is located below the dielectric substrate. The present invention firstly designs a broadband dual-polarization cross-dipole antenna covering 1.7-3.6GHz using a coplanar waveguide feeding structure, and then designs a coplanar waveguide DMS-DGS hybrid third-order band-stop filter, and prints a miniaturized and highly selective coplanar waveguide filter and antenna on the same dielectric substrate, thereby achieving a stop band covering 2.9-3.1GHz. Under the condition of VSWR<2, compared with the original broadband antenna covering the 1.7‑3.6 GHz frequency band, the proposed notch antenna operates in two operating frequency bands, 1.7‑2.7 GHz and 3.4‑3.6 GHz, and introduces a notch frequency band covering 2.9‑3.1 GHz. The notch antenna can be used for 2G / 3G / 4G / 5G base station applications that require notch function.

The topological structure comprises a third microstrip line, one end of the third microstrip line is symmetrically connected with one end of a first parallel line and one end of a second parallel line, and the other end of the first parallel line is connected with an input end and one end of a first microstrip line. The other end of the second parallel line is connected with an output end and a second open-circuit branch knot, the other end of the first microstrip line is connected with one end of a second microstrip line, the other end of the second microstrip line is connected with a first open-circuit branch knot, and the other end of the third microstrip line is symmetrically connected with one end of a fourth microstrip line and one end of a sixth microstrip line. The other end of the fourth microstrip line is connected with one end of a fifth microstrip line, the other end of the fifth microstrip line is connected with a third open-circuit branch knot, and the other end of the sixth microstrip line is connected with one end of a seventh microstrip line. The broadband dual-notch band-pass filter solves the problems that an existing broadband dual-notch band-pass filter is poor in selectivity and large in size.

Light-filtering eyewear is provided that comprises a polymer substrate, at least three absorbing compounds combined with the polymer substrate, and a lens material combined with the polymer substrate and absorbing compounds, wherein the absorbing compounds each absorb light in a notch band having a full-width half maximum of no more than 40 nm. The absorbing compounds can be provided in combination so that, for light produced by a display screen that is transmitted through the light-filtering eyewear, the correlated color temperature is within 1000 Kelvin of the correlated color temperature for light produced by the display screen that is not transmitted through the light-filtering eyewear. Peak absorptions for the first, second, and third absorbing compounds can be between 436 nm-522 nm, 548 nm-616 nm, and 643 nm-730 nm, respectively. In some embodiments, a fourth absorbing compound can be provided in combination with the polymer substrate and absorbing compounds having peak absorption between 417 nm-465 nm.