34results about How to "Good out-of-band suppression" patented technology

The present invention provides an optical filter and an optical device using same, the optical filter comprising: a cladding layer; a plurality of metallic patterns regularly patterned on the claddinglayer; and an optical waveguide layer formed over the plurality of metallic patterns, wherein light proceeds from the optical waveguide layer to the cladding layer.

The invention discloses a tunable filter, which comprises a cavity and a tuning mechanism. At least three waveguide resonant cavities are arranged in the cavity, direct coupling is realized between adjacent waveguide resonant cavities through a direct coupling window, cross coupling is realized between non-adjacent waveguide resonant cavities through a cross coupling structure, at least one slit is arranged on the cavity wall at the same side of each waveguide resonant cavity, and the electrical length of each slit is less than the half-wavelength of the highest working frequency of the tunable filter; the tuning mechanism comprises a group of dielectric sheets and a driving mechanism, wherein the dielectric sheets are in one-to-one correspondence with the slits, and all the dielectric sheets can be simultaneously inserted into the corresponding waveguide resonant cavities at the same depth without friction through the corresponding slits under the driving of the driving mechanism. Theinvention also discloses a tunable duplexer. The tunable filter and the tunable duplexer have good out-of-band rejection characteristic, and in the whole tuning range, the relative position of the transmission zero and the bandwidth of the pass band is basically kept unchanged, and the echo of the filter is kept at a better level.

The invention discloses a three-pass band power dividing filter based on a multi-mode fork resonator, which comprises a dielectric substrate, a metal grounding plate is provided on the bottom surface of the dielectric substrate, and an input port feeder, a first output feeder and a second feeder are provided on the top surface. The output feeder, the input port feeder is located in the middle of the dielectric substrate, the first output feeder and the second output feeder are symmetrically arranged on both sides of the input port feeder; the input port feeder and the first output feeder are respectively provided with a first fork A three-mode fork resonator and a second fork-shaped three-mode resonator; a third fork-shaped three-mode resonator and a fourth fork-shaped three-mode resonator are respectively arranged between the input port feeder and the second output feeder.

A wideband piezoelectric filter with a ladder-type is provided, which is composed of a plurality of first resonators connected in series, a plurality of second resonators connected in parallel, an impedance matching device disposed near the input terminal or the output terminal of the filter, and at least one special parallel ground path led out from serial nodes. The special parallel ground path at least comprises one inductor having a larger inductance value, and a resonator having the same resonant frequency as a serial branch or a capacitor, wherein the larger inductor is connected to the resonator or capacitor in series in the parallel path. The ladder filter according to the invention can have a bandwidth which is more than twice that of the conventional ladder filter, and also has excellent out-of-band rejection characteristics.

The present invention provides a microstrip antenna with a filtering feature and a design method thereof. The microstrip antenna comprises a circular microstrip antenna, a T-shaped resonator and a microstrip rectangular snap ring resonator, the circular microstrip antenna is provided with a rectangular notch, a vertical arm, distributed along a y shaft, of the T-shaped resonator is inserted into the rectangular notch of the circular microstrip antenna, and a horizontal arm, distributed along an x shaft, of the T-shaped resonator is arranged close to the microstrip rectangular snap ring resonator. The design method comprises the steps of: designing resonant frequency meeting the three-order Chebyshev coupling band-pass filter demand, designing a coupling coefficient between the T-shaped resonator and the microstrip rectangular snap ring resonator, and designing that the demand of the filter to the quality factor of the circular microstrip antenna is met. The microstrip antenna is compact in structure, has frequency filter features being similar to a traditional band-pass filter, the antenna gain is flat in the passband, and the radiation feature is good; and moreover, the microstripantenna has a good out-of-band rejection feature out of the frequency band and can effectively isolate the out-of-band interference signals.

The invention discloses a three-passband power dividing filter with high frequency selectivity. The three-passband power dividing filter comprises a dielectric substrate, a metal grounding plate is arranged on the lower surface of the dielectric substrate, and an input port feeder line, a first output feeder line and a second output feeder line are arranged on the upper surface of the dielectric substrate. The input port feeder line, the first output feeder line and the second output feeder line are all located on the same side of the central axis of the dielectric substrate, and one end of the first output feeder line is connected with one end of the second output feeder line; a first resonance unit, a second resonance unit, a third resonance unit and a fourth resonance unit are sequentially coupled and connected between the input port feeder line and the first output feeder line as well as between the input port feeder line and the second output feeder line, and the four resonance units have the same structure and respectively comprise a band-pass resonator and two band-stop resonators with different sizes; and a port isolation resistor is arranged between the first output feeder line and the second output feeder line. The three-passband power dividing filter has high frequency selectivity, out-of-band harmonic suppression, power distribution characteristics and filtering characteristics.

The invention discloses a double-end constant-resistance filtering assembly, which comprises an input terminal 1, an output terminal 2, inductors L1, L2, L3, L4 and L5, and resistors R1 and R2. The input terminal 1 is connected with the input end of the inductor L1. The output end of the inductor L1 is connected with the input end of the inductor L2, the output end of the inductor L2 is connectedwith the input end of the inductor L3, and the output end of the inductor L3 is connected with the output terminal 2; the input ends of the inductors L1 and L4 are connected with a capacitor C1 in parallel, the output ends of the inductors L1 and L4 are connected with a capacitor C2 in parallel, the input ends of the inductors L3 and L5 are connected with a capacitor C3 in parallel, and the outputends of the inductors L3 and L5 are connected with a capacitor C4 in parallel. The resistor R1 and the capacitor C5 are connected in series and then connected to the two ends of the inductor L4 in parallel, and the resistor R2 and the capacitor C6 are connected in series and then connected to the two ends of the inductor L5 in parallel. The invention provides a double-end constant-resistance filtering assembly with an ultra-wideband response working frequency band, a good out-of-band rejection characteristic and any cut-off frequency filtering design.

The invention discloses a bandpass filter based on a fan-shaped microstrip resonator, which includes a fan-shaped microstrip resonator, input and output feeders, and metallized through holes. The metallized through holes serve as a disturbance structure to make the first two The resonant frequency of the resonant mode is close to form a passband. At the same time, using the signal phase theory, a transmission zero is introduced in the stopband without changing the size and structure of the original resonant cavity, achieving better out-of-band suppression characteristics. The invention can be used in microwave and millimeter wave communication and radar systems with higher requirements for out-of-band suppression performance. At the same time, the invention also has the advantages of miniaturization, light weight, easy integration and low cost, and can better adapt to the requirements of modern communication and radar systems.

The invention discloses a four-pass band power dividing filter based on a four-mode resonator, which includes a dielectric substrate, a metal grounding plate is provided on the bottom surface of the dielectric substrate, and an input port feeder, a first output feeder and a second output feeder are provided on the top surface , the input port feeder is located in the middle of the dielectric substrate, the first output feeder and the second output feeder are symmetrically arranged on both sides of the input port feeder; the input port feeder and the first output feeder are respectively provided with a first four-mode resonance and a second four-mode resonator; a third four-mode resonator and a fourth four-mode resonator are respectively arranged between the input port feeder and the second output feeder.

The invention discloses an improved microwave electric coupling structure and an implementation method therefor. According to the microwave electric coupling structure, electric coupling between substrate integrated waveguides with open boundaries can be implemented; and a microwave device with a high performance index can be implemented when the microwave electric coupling structure is applied tothe devices, such as a filter, an oscillator, an antenna and a coupler.

The invention relates to a novel double-frequency narrow-band bandpass filter. The novel double-frequency narrow-band bandpass filter comprises a metal microstrip line on the front surface, a medium plate layer, an input port and an output port on the middle part, and a metal plating layer on the rear side of a medium plate, wherein in the metal microstrip line, a resonator consisting of a section of low impedance line and a stepped impedance line connected with the low impedance line, and a novel resonator formed by connecting a quarter wavelength uniform impedance line and a feeder with a rectangular short microstrip line. The resonator structure is symmetrical, so that an odd-even mode theory can be used for analyzing the resonator structure; and the input port and the output port of the feeder are in the same level line. A transmission zero is inserted into a stop band between two pass bands, a zero position in a transmission characteristic curve can be flexibly adjusted, the stop band characteristics are improved, and a transmission zero is inserted outside two center frequencies respectively to improve out-of-band rejection characteristics. The novel double-frequency narrow-band bandpass filter has a simple structure and extremely high frequency selectivity and meets the requirements on miniaturization.

The invention discloses a harmonic inhibition coaxial chamber filter. The harmonic inhibition coaxial chamber filter comprises two mirror image symmetric coaxial resonant chambers, wherein a couplingresonant window is arranged between the two coaxial resonant chambers, the coaxial resonant chambers are internally provided with main resonance metal columns, primary harmonic auxiliary resonance metal columns, secondary harmonic auxiliary resonance metal columns and feed units, a top portion of the coaxial resonant chambers is equipped with a fine tuning metal screw in a coaxial relationship with the main resonance metal columns, the main resonance metal columns, the primary harmonic auxiliary resonance metal columns and the secondary harmonic auxiliary resonance metal columns are respectively perpendicularly mounted at a bottom portion of the coaxial resonant chambers, the main resonance metal columns and the coaxial resonant chambers are coaxially arranged, the feed units comprise input output ports and coupling feed metal columns, the input output ports are coaxial feed wires, a top portion of the coupling feed metal columns is connected with the top portion of the coaxial resonant chambers, a bottom portion of the coupling feed metal columns is connected with inner conductors of the coaxial feed wires. The harmonic inhibition coaxial chamber filter is advantaged in that in-band filtering characteristics and out-band primary harmonic and secondary harmonic inhibition characteristics can be excellently realized.

The invention discloses a three-pass band power dividing filter with high frequency selectivity, which comprises a dielectric substrate, a metal grounding plate is arranged on the lower surface of the dielectric substrate, and an input port feeder, a first output feeder and a second feeder are arranged on the upper surface of the dielectric substrate. Two output feeders, the input port feeder, the first output feeder and the second output feeder are all located on the same side of the central axis of the dielectric substrate, one end of the first output feeder is connected to one end of the second output feeder; the input port feeder and the first output feeder , The connection between the second output feeder line is sequentially coupled with the first resonant unit, the second resonant unit, the third resonant unit and the fourth resonant unit. The four resonant units have the same structure, and each includes a bandpass resonator and two Band-stop resonators with different sizes; port isolation resistors are provided between the first output feeder and the second output feeder. The three-pass band power dividing filter has good frequency selectivity, out-of-band harmonic suppression, power distribution characteristics and filtering characteristics.

The present invention provides a dual-pass band-pass filter based on asymmetric coupled lines, which includes a dielectric substrate, a filter located on the upper surface of the dielectric substrate, and a metal ground plate located on the lower surface of the dielectric substrate. The filter includes an improved H-type multimode resonator, asymmetric parallel coupling lines loaded on the left and right sides of the multimode resonator, stepped impedance branches loaded on the upper and lower sides of the multimode resonator, parallel three-wire coupling composed of high impedance lines and parallel coupling lines Line, open stub loaded on the underside of the left port feeder. The invention adopts the multi-mode resonator loaded with stepped impedance branches and the strong coupling of the asymmetric coupling line structure, which not only improves the selectivity of the pass band, but also reduces the size of the filter. The insertion loss in the two passbands is low and adjustable, the out-of-band characteristics are good, the structure is compact, the cost is low, the processing is convenient, and it is easy to integrate with other circuits.

The invention discloses an octagonal ultra-wideband microstrip filter based on a defected ground structure. The ultra-wideband filter comprises an upper signal layer, a middle metal grounding layer and a bottom signal layer which are successively arranged. The upper signal layer comprises a medium substrate, a first input / output port, a second input / output port, a first octagon transmission unit and a second octagon transmission unit. The middle metal grounding layer comprises a first octagon defect unit and a second octagon defect unit. The bottom signal layer comprises the medium substrate,a third octagon transmission unit, a fourth octagon transmission unit, a uniform microstrip transmission line and an open circuit stub line. In the invention, the strong coupling effect of an octagonal defected-ground coupled transmission line is used to realize a ultra wide band, an open circuit branch knot is used to realize ultra wide out-of-band harmonic wave suppression, the design is simple,processing is convenient and cost is low.

The invention discloses a high-selectivity three-pass band power dividing filter, which comprises a rectangular dielectric substrate, a metal grounding plate is provided on the lower surface, and an input port feeder, a first output port feeder and a second output port feeder are provided on the upper surface , a first coupled microstrip strip is provided between the first output port feeder and the input port feeder, and a second coupled microstrip strip is provided between the second output port feeder and the input port feeder. The first coupled microstrip strip connects the first half-wavelength open line and the third coupled microstrip strip; the second coupled microstrip strip connects the second half-wavelength open line and the fourth coupled microstrip line strip; the fifth coupled microstrip line strip is shorted to the metal ground plate and connected to the front end of the first terminal open stub, and the sixth coupled microstrip line strip is shorted to the metal ground plate and connected to the front end of the second terminal open stub. The invention discloses a high-selectivity three-pass band power dividing filter, which has the advantages of compact structure, low loss, high selectivity, good isolation, and good out-of-band suppression performance.