69 results about "Microstrip bandpass filter" patented technology

A solid-state microwave generator for applying energy to a load disposed in a cavity is provided. The microwave generator comprises an oscillator, a preamplifier coupled to the oscillator, a power amplifier coupled to the preamplifier; a radiating element coupled to the power amplifier and in communication with the cavity; and a passive, microstrip bandpass filter with a predetermined passband in the microwave region of the electromagnetic spectrum connected in a line between the oscillator and the power amplifier. The output of the passive, microstrip bandpass filter is connected to an input of the power amplifier to limit the energy transmitted by the radiating element into the cavity at frequencies outside of the passband.

The invention relates to a microstrip bandpass filter with a sector open-circuit structure, belonging to the technical field of microwave/millimeter wave devices and relating to a microwave/millimeter wave integrated circuit. Based on a traditional parallel coupling microstrip line filter, the microstrip bandpass filter with the sector open-circuit structure adds two sections of sector open-circuit shunts; either sector open-circuited shunt is a one-fourth wavelength terminal open-circuit line with a sector-structure end terminal; and the start terminals of the two sections of sector open-circuit shunts are perpendicularly connected with a center point of an auxiliary microstrip line. The invention has the advantages of simple form, compact structure and high beyond-strip attenuation, not only can be used in a microwave/millimeter wave integrated circuit, but also can be used in a submillimeter wave band with higher frequency. Meanwhile, an input microstrip line and an output microstrip line of the microstrip bandpass filter with the sector open-circuit structure are on the same straight line, thereby facilitating the application in practical projects.

The invention provides a double-frequency band-pass filter, which belongs to the design field of microwave and millimeter wave devices. The filter comprises a first metal patch, a second metal patch and a medium substrate, wherein the two metal patches are respectively wrapped on the upper surface and the lower surface of the medium substrate; the first metal patch consists of an input feeder line, an output feeder line and two three-mode stepped impedance resonators; the two resonators are respectively provided with three metallized through holes; and three metallized through holes corresponding to the first metal patch are arranged on the second metal patch. The double-frequency band-pass filter is designed by using two three-mode stepped impedance resonators which are loaded by stub lines; each resonator can generate and independently control a pass band; the bandwidths of the two pass bands are respectively 15.4 % and 10.2 %; four transmission zero points are generated, so that the band-pass filter has the characteristics of high frequency selection performance, independent pass band control, low cost, high performance, small size and adjustable pass band widths.

The invention discloses a multi-band tunable microstrip band-pass filter which comprises a three-layer structure: a front metal microstrip line, a middle dielectric plate layer, input and output ports and an earthing metal through hole, and a metal coating at the back of a dielectric plate, wherein the metal microstrip line is a symmetric resonator consisting of a half-wavelength uniform impedance line resonator and an open-loop dual-mode resonator; the two resonators share input and output coupling lines; and a variable capacitance diode is loaded between the tail end of the open-loop dual-mode resonator and the earthing metal through hole to form a tunable structure. The filter is compact in structure, low in passband insertion loss, steep in passband edge and high in selectivity, and meets a development trend of filter miniaturization.

The invention discloses an adjustable microstrip band-pass filter with an adjustable center frequency and an invariable absolute bandwidth. The adjustable microstrip band-pass filter comprises a microstrip structure, a dielectric substrate, and grounding metal. The microstrip structure comprises an input port, an input feed circuit, an input coupling matching circuit, an E-type dual-mode adjustable resonator, an output coupling matching circuit, an output feed circuit, and an output port. Microstrip line branches on both sides of the E-type dual-mode adjustable resonator are connected with variodes respectively. A middle microstrip line branch is connected with a variode through a capacitor. The input feed circuit comprises a horizontal microstrip line and a vertical microstrip line. The horizontal microstrip line extends to a position right between the two adjacent microstrip line branches of the E-type dual-mode adjustable resonator. The input coupling matching circuit comprises two coupled capacitors connecting the vertical microstrip lines with the microstrip line branches at both sides. The whole adjustable microstrip band-pass filter has structure of mirror symmetry, an adjustable center frequency, and an invariable absolute bandwidth, and can be used in a reconfigurable radiofrequency front-end system.

The invention discloses a micro-strip dual-mode filter with intensified coupling and harmonic suppression characteristics, which is a microwave band-pass filter with high performance. A microwave dielectric substrate comprises a square ring resonator (1), an L-shaped coupling structure, a perturbation element (3) and a 50-ohm incoming and outgoing feeder, wherein, the L-shaped coupling structure at the input end (21) and the L-shaped coupling structure at the output end (22) are symmetrically distributed corresponding to a diagonal of the square ring resonator (1); the L-shaped coupling structure at the input end (21) is connected with the 50-ohm incoming feeder (41); the L-shaped coupling structure at the output end (22) is connected with the 50-ohm outgoing feeder (42); the perturbation element (3) is positioned on a corner of the square ring resonator (1) and is connected with the square ring resonator (1). The dual-mode micro-strip band-pass filter is applicable to the design of mobile communication radio frequency (RF) front end, can obtain greater port coupling quantity than traditional micro strip, thereby reducing the insertion loss, and very effectively suppressing the higher harmonic response simultaneously.

The invention provides an X-band broadband micro-strip band-pass filter comprising an input micro-strip line part, an output micro-strip line part, and a plurality of micro-strip line structures. The micro-strip line structures are arranged in an up-and-down alternating way to form a structure of bilateral symmetry, and the parallel cross parts of all the micro-strip line structures are of the same length. The X-band broadband micro-strip band-pass filter of the invention is designed on the basis of a parallel coupled micro-strip band-pass filter, and part of parallel coupled resonance is overturned to make the micro-strip line structures arranged in an up-and-down alternating way to form a structure of bilateral symmetry. Under the same index, the design size of the X-band broadband micro-strip band-pass filter is greatly reduced compared with a traditional parallel coupled line filter, and the volume is about one third that of the traditional model.

Methods and systems for a programmable coplanar or microstrip bandpass filter for undersampling in a receiver are disclosed and may include band-limiting a received wireless signal utilizing one or both of a programmable microstrip bandpass filter and a coplanar waveguide bandpass filter and undersampling the band-limited received wireless signal. A center frequency of the programmable microstrip bandpass filter may be tuned by adjusting a capacitance or an inductance of the programmable microstrip bandpass filter. The bandwidth of the programmable microstrip bandpass filter may be also be adjusted. A center frequency of the programmable coplanar waveguide bandpass filter may be tuned by adjusting a capacitance or an inductance of the programmable coplanar waveguide bandpass filter. The bandwidth of the programmable coplanar waveguide bandpass filter may also be adjusted. The band-limited, received wireless signal may be undersampled utilizing a sample and hold circuit.

The invention relates to a T-shaped grooved triangular patch dual-mode micro-strip band pass filter. The filter is characterized by comprising a triangular patch (1), wherein the triangular patch (1) is of an isosceles triangle; the middle part of the triangular patch (1) is provided with an inverse 'T'-shaped groove (2); the bottom edge of the triangular patch (1) is symmetrically provided with two rectangular grooves (3); and feeder lines (4) connected with the triangular patch (1) are arranged in the two rectangular grooves (3). The T-shaped grooved triangular patch dual-mode micro-strip band pass filter provided by the invention changes the conventional equilateral triangle into the isosceles triangle and is provided with the 'T'-shaped groove, so the performance of the micro-strip band pass filter is superior to that of the band pass filters of other shapes.

The invention discloses a microwave low-band ultra-micro micro-strip diplexer. A circuit composition of the microwave low-band ultra-micro micro-strip diplexer comprises three micro-strip band-pass filters and two 3dB quadrature bridges, one end of a first filter is connected with an input/output interface of a first bridge, the pass-band frequency of the first filter is different from those of a second filter and a third filter, the pass-band frequencies of the second filter and the third filter are same, and the second filter and the third filter are parallelly connected between coupling ends and straight-through ends of the first bridge and a second bridge. The micro-strip diplexer is formed by the micro-strip band-pass filters with good selectivity and the 3dB quadrature bridges with functions of signal decomposition, synthesis and reflection. The micro-strip diplexer has good input/output standing wave ratio, circuits are easy to be in cascade connection with pre-stage and post-stage circuits, ultra-fine micro-strip thin-film technology is adopted, and the circuits have good consistency, compact structure and small volume, thereby ensuring that the microwave low-band ultra-micro micro-strip diplexer has high selectivity and high integration level and is widely applied to the technical field of communication.

The invention belongs to the technical field of communication, and provides a microstrip bandpass filter in order to overcome the disadvantages of poor frequency selectivity, large size and the like of existing microstrip bandpass filters. A physical mechanism is analyzed deeply, and the design process is elaborated. Final simulation results and test results show that the microstrip bandpass filter has transmission zero points on each side of a passband, which can effectively improve the frequency selectivity; a third transmission zero point is generated at a specified frequency position to enhance an out-of-band inhibiting capability, and the method has high performance, small size, easy design and the like.

The invention discloses a T-shaped micro-strip dual-mode band-pass filter. The T-shaped micro-strip dual-mode band-pass filter is characterized by comprising a T-shaped patch, wherein two sides of one end of the T-shaped patch are respectively connected with a feeder line in a slot coupling mode; an opening is formed at a joint of the feeder line and the T-shaped patch; and two side ends of the T-shaped patch extend into the opening, and slots are reserved. With the T-shaped patch, the T-shaped micro-strip dual-mode band-pass filter is superior to band-pass filters in other shapes in terms of performance.

The invention discloses a high-working-frequency ceramic-base micro-band band-pass filter. The high-working-frequency ceramic-base micro-band band-pass filter comprises a MgTiO3 ceramic substrate (9),and a metal grounding plate (8) is arranged on the back face of the MgTiO3 ceramic substrate (9); an input feeder (1) is arranged at the upper left portion of the front face of the MgTiO3 ceramic substrate (9), and an input parallel coupling line (3) and an input parallel coupling line (4) are arranged on one inward side of the input feeder (1); an output feeder (2) is arranged at the lower rightportion of the front face of the MgTiO3 ceramic substrate (9), and an output parallel coupling line (5) and an output parallel coupling line (6) are arranged on one inward side of the output feeder (2); an output parallel coupling line (7) is arranged in the middle of a connecting line between the input feeder (1) and the output feeder (2); the input feeder (1) and the output feeder (2) are micro-band lines with the characteristic impedance of 50 ohm, and are of parallel coupling feeding structures. According to the high-working-frequency ceramic-base micro-band band-pass filter, the size ofthe filter is decreased, insertion loss in a passband is reduced, higher harmonics can be effectively controlled, the center frequency of the pass band is easily controlled, the structure is simple, and processing is easy.

The invention discloses a micro-strip double-mode band-pass filter, comprising a round chip, wherein the round chip is connected with two feeder lines which are vertical mutually; the round chip is provided with a slotted hole; and two notches are arranged at two sides of each feeder line symmetrically. In the micro-strip double-mode band-pass filter, the round chip is slotted so as to realize a double-mode band-pass filter. The performances of the micro-strip double-mode band-pass filter are superior to those of other shaped band-pass filters.

The invention discloses a broadband single-ended microstrip short-line band-pass filter, which comprises a first feeder line, a second feeder line, a 1/8 wavelength coupling microstrip line, first tofourth chip capacitors, a first metallized through hole and a second metallized through hole. One end of the 1/8 wavelength coupling microstrip line is connected with the first feeder line, the second feeder line, the first chip capacitor, the third chip capacitor and the fourth chip capacitor, and the other end of the one-eighth wavelength coupling microstrip line is grounded through the first metallized through hole. The first chip capacitor is loaded on the inner side of one end of the coupling microstrip line in series, the third chip capacitor and the fourth chip capacitor are loaded onthe outer side of one end of the coupling microstrip line in parallel, and the other end of the third chip capacitor and the other end of the fourth chip capacitor are grounded through the second metallized through hole. And the second chip capacitor is loaded on the inner side of the middle part of the coupling microstrip line in series. Compared with an existing broadband single-ended microstripband-pass filter, the broadband filter response is obtained, meanwhile, the circuit size is greatly reduced, the loss is extremely low, and the structure is simple.

The invention discloses a four-band microstrip band-pass filter with notch characteristics and a design method thereof. The four-band microstrip band-pass filter with notch characteristics includes aconductor band, a dielectric substrate, and a circuit board of a grounding board. The circuit board is provided with a short-hole perforation. The conductor band includes an input port, an output port, a feeder line, two first stepped impedance resonators, two second stepped impedance resonators, and two F-type open-circuit branches, wherein the feeder line is connected between the input port andthe output port; the two first stepped impedance resonators are connected to the upper end portion of the feeder line; the two second stepped impedance resonators are connected to the lower end portion of the feeder line; the two F-type open-circuit branches are connected to the upper end portion of the feeder line; and the first stepped impedance resonator is located between the two F-type open-circuit branches. The four-band microstrip band-pass filter has notch characteristics, can realize band-pass filtering of four frequency bands simultaneously, and has a simple structure, small size, high integration, excellent performance, and good compatibility.

The invention relates to an adjustable microstrip band-pass filter with an adjustable center frequency and unchanged absolute bandwidth, and the filter comprises a metal rectangular cavity which comprises a cavity upper cover and a cavity pedestal, wherein the cavity upper cover and the cavity pedestal are fixedly connected through cavity fixing screws at four corners to form a resonant cavity. The cavity pedestal is provided with a cavity groove for realizing cavity resonance. The filter also comprises a microstrip line plate which is fixed inside the metal rectangular cavity through a cavityfixing screw, and is opposite to the cavity groove. The adjustment of the center frequency is achieved by a variable-capacity third-order LC resonant structure. Compared with the prior art, the filter has tunable center frequency, and facilitates the debugging.

The disclosed embodiments provide an absorptive coupled-line bandpass filter. This bandpass filter includes a first port, which is coupled to a first absorptive stub, and a second port, which is coupled to a second absorptive stub. The bandpass filter also includes a coupled-line bandpass section coupled between the first and second ports, wherein the coupled-line bandpass section comprises a set of one or more parallel strip line resonators, which are coupled together in series and are coupled to the first and second ports through overlapping coupled-line sections, wherein at a center frequency of a passband for the absorptive coupled-line bandpass filter, the first and second absorptive stubs appear as open circuits, and outside of the passband, the first and second absorptive stubs appear as matched loads to ground and contribute to absorption of out-of-band signals.

The invention belongs to the technical field of microwaves, and particularly relates to a four-order microstrip band-pass filter with a diagonal coupling box type topological structure. The filter comprises three isosceles right triangle patch resonators, a stepped impedance microstrip line resonator and input and output feeder lines, wherein the three isosceles right triangle patch resonators arearranged side by side in a stepped shape and have short-circuited right-angle ends; the stepped impedance microstrip line resonator is positioned above the three isosceles right triangle patch resonators with short-circuited right-angle ends; and gaps exist among the three isosceles right triangle patch resonators with the short-circuited right-angle ends, and gaps exist between the stepped impedance microstrip line resonator and the three isosceles right triangle patch resonators with the short-circuited right-angle ends. The filter not only can realize the characteristics of on-demand configuration of two limited transmission zeros, including asymmetric frequency response, approximate elliptical response and linear phase response, but also can realize product miniaturization.

The invention relates to a micro wave and micro band band-pass filter for a miniature large double-frequency ratio wide band. The band-pass filter is characterized in that one end of an open-circuit branching line is connected with the center of a high-resisting line, and two ends of the high-resisting line are respectively connected with a short circuit branching line; a symmetrical center on the high-resisting line is connected with two outer stepping impedance lines and two inner stepping impedance lines, the two inner stepping impedance lines are connected onto the high-resisting line on one side of the open-circuit branching line, and the two outer stepping impedance lines and the two inner stepping impedance lines are symmetrical with the open-circuit branching line; two short circuit branching lines are respectively connected with an SMA (small-motion accelerator) through a feed line of 50ohm; and the end of each short circuit branching line is provided with a grounding hole. The band-pass filter has the following advantages that a size of the filter is small, band pass is realized through a double-frequency wide band, isolation between passing bands is high, and a double-frequency ratio is large. By the adoption of the band-pass filter, the requirement on processing precision is low, the realization is simple, the cost of construction is low, and the production is convenient.