CN102646140A

CN102646140A - Public-terminal impedance matching structure and public-port impedance matching method of combiner

Info

Publication number: CN102646140A
Application number: CN2011100720193A
Authority: CN
Inventors: 杨波; 王刚; 方建云
Original assignee: CHANGSHU DONGFANG POST AND TELECOMMUNICATION FACTORY
Current assignee: CHANGSHU DONGFANG POST AND TELECOMMUNICATION FACTORY
Priority date: 2011-03-24
Filing date: 2011-03-24
Publication date: 2012-08-22

Abstract

The invention discloses a public-terminal impedance matching structure and a public-port impedance matching method of a combiner. The structure is connected with a resonator in each channel through conducting materials, and then connected with the public port of the combiner through a small hole between upper and lower baffles. The method comprises the following steps: firstly, carrying out optimized de-gardening on a multiple-port network coupled matrix of the combiner so as to obtain a coupled matrix representing coupling coefficients among the resonators and a coupling relation between ports and resonators, wherein coupling coefficients m0, 1-m0 and i of a public port and each resonator adjacent to the public port can be obtained through the coupled matrix; and obtaining a relation among an external Q value of a filter and the coupling coefficients according to a filter network integrated design formula, and establishing a relation between a reflection group delay and the external Q value. Compared with the prior art, the method disclosed by the invention are easy to operate; and because the reflection group delay of a port can be obtained through electromagnetic simulation, the implementation mode and position of public-port impedance matching of the combiner can be accurately predicted through computing simulation.

Description

Combiner common port impedance matching structure and public port impedance matching methods thereof

Technical field

The present invention relates to the method and the structure thereof of the impedance matching of a kind of combiner public port; Specifically be a kind of about being applied to the method for base station cavity combiner public port impedance matching; Whether the common port impedance that can judge combiner through this method rapidly matees, and has avoided unnecessary repetitive operation.

Background technology

Combiner is claimed frequency demultiplexer again, is mainly used in the separation that realizes unlike signal and perhaps synthesizes.Combiner can be regarded as a plurality of parallel connection or series connection with wave filter of specific passband, but it absolutely not simply connects again.One group of wave filter directly links to each other, and owing to effect each other, with the performance that has a strong impact on them, even can not work, and is as shown in Figure 1.Its reason just is that common port input impedance becomes and has not matched.

The method for designing of combiner comprises that mainly the use power splitter connects at present; Circulator connects, perhaps connects with the certain-length transmission line, but no matter be which kind of method; Realize the impedance matching of public port; All need be in practice process through a large amount of trials, at this moment, can not ignore because each interchannel at combiner public port place influences each other greatlyyer.

Summary of the invention

The object of the present invention is to provide a kind of public port of combiner fast and effectively impedance matching methods, be convenient to instruct the actual production debugging.A kind of combiner public port matching structure of making according to preceding method that is easy to realize is provided simultaneously.

The technical scheme that adopts of the present invention is: a kind of combiner public port impedance matching methods; It is characterized in that: at first; Through the optimization garden that disappears to combiner multiport network coupled matrix; Obtain representing the coupled matrix of the coupled relation of coupling coefficient and port and resonator between each resonator, from this coupled matrix, can draw the coupling coefficient m of public port and adjacent each resonator _0,1– m _{0, i}Secondly, according to FL-network comprehensive Design formula:

Obtain the outside Q value of wave filter and the relation between the coupling coefficient, and set up the relation of reflection group time delay and outside Q value;

Further; The relation of said reflection group time delay and outside Q value is established as: the value that calculates the reflection group time delay under the impedance matching state of realizing ideal through

; Through the concrete implementation optimization Simulation of electromagnetic field simulation software to the impedance matching of combiner public port, the reflection group time delay value that emulation is obtained goes to approach and calculated value.

The present invention also provides a kind of combiner common port impedance matching structure, it is characterized in that: be to be linked to each other with the resonator of each passage by conductive material, link to each other with the public port of combiner through the aperture between last lower baffle plate.

The invention has the advantages that: compared with prior art; This combiner public port impedance matching methods clear principle; Simple to operate; And obtain because the reflection group time delay of port can be passed through Electromagnetic Simulation, thereby set up Theoretical Calculation and put into practice the direct relation of producing, so can make prediction more accurately to the implementation and the position of the impedance matching of combiner public port through calculating emulation.

Description of drawings

Below in conjunction with accompanying drawing the present invention is further specified.

Fig. 1 is the family curve after the wave filter simple combination.

Fig. 2 is a cross-couplings circuit equivalent circuit model.

Fig. 3 is the unit's order that disappears of coupled matrix.

Fig. 4 is the topological structure of multiport coupling network.

Fig. 5 is the coupled matrix of multiport network.

Fig. 6 is the family curve after Fig. 1 optimizes.

Fig. 7 closes terminal public port matching structure.

Fig. 8 is the tri-frequency combiner family curve that adopts the common port impedance matching methods to realize.

Embodiment

According to the circuit model of A. E. Atia at the cross-couplings wave filter of proposition in 1972; As shown in Figure 2; Can know; For electric coupling, magnetic coupling and electromagnetism hybrid coupled, all can obtain unified coupled matrix form:

.Wherein the element among the coupled matrix M has been represented the coupling coefficient between each resonator, and coupled matrix finally can obtain the coupled matrix that needs again through the rotary process unit that disappears.Its rotary process disappear the unit concrete steps following:

With one be example with 8 rank wave filters, the structure that provides its coupled matrix and the unit's order that disappears, as shown in Figure 3.Coupled matrix has symmetry, so only provided the element of the first half, remaining can obtain according to symmetry.S representes the skew of resonance frequency among the figure, and m is an adjacent coupled between the chamber, and c is a cross-couplings.The unit's order that disappears of representing matrix.Disappear unit order always along the right of row to the left side, the top of row is to following, ranks are staggered to carry out.

And for combiner, can regard it as the network topology structure of a multiport, as shown in Figure 4, wherein on behalf of port node, square frame, circle represent the resonator node, electric wire representative coupling.Obtain corresponding coupled matrix through the structure above the analogy; It is as shown in Figure 4 that (wherein

is the matrix of

, the coupling between each port of its element representation and each resonator;

is the matrix of , the coupling between each resonator of its element representation.); Fig. 5 is different with the coupled matrix that the front is carried; Not only comprised the coupled relation between each resonator among the coupled matrix M of this moment; And because the existence of

matrix makes the coupled relation of port and resonator also be incorporated in the matrix M.The purpose of doing like this is to have avoided uncared-for factor in the former design, thereby guaranteed the accuracy of later stage emulation making Unified Treatment in each interchannel introducing band coupled matrix that influences each other of public port place.After having set up the coupled relation of port and resonator,, can obtain the coupling coefficient m of public port and adjacent each resonator through the disappear mode of unit of rotation _0,1– m _{0, i}, the coupling coefficient of this moment since through optimize and the unit that disappears after obtain, so offset the influence of reactance, so the wave filter that is connected in parallel can both be operated in desirable duty, as shown in Figure 6.

According to FL-network comprehensive Design formula: (wherein,, is respectively high-frequency cut-off frequency, low-frequency cut-off frequency, the passband central frequency of BPF.; ) can obtain the outside Q value of wave filter and the relation between the coupling coefficient.And the reflection group time delay has comprised the full detail that designs and debug wave filter in the coupling resonance wave filter; It can be used for judging the level of impedance match of public port; So the relation of reflection group time delay and outside Q value of only need setting up gets final product, (be coupling coefficient port resonator between through

this moment.) value that calculates, be the reflection group time delay value under the impedance matching state of realizing ideal.Through electromagnetic field simulation software the concrete implementation of combiner public port impedance matching is optimized emulation at last, the reflection group time delay value that emulation is obtained goes to approach with calculated value and gets final product.

As with the corresponding combiner port match of preceding method structure; Then be to link to each other with the resonator 3 of each passage 2 by conductive material 1; Again through overhead gage 4, down between the aperture 6 of baffle plate 5 link to each other with the public port 7 of combiner and realize that its structure can be consulted shown in Figure 7.

With a tri-frequency combiner is example, and passband covers 1.785 ~ 1.805GHz, 2010 ~ 2025GHz, 2400 ~ 2483GHz.The topological structure of each passage is as shown in Figure 4.After extracting coupled matrix it is rotated the unit that disappears, nonzero element is in this coupled matrix:

The characteristic of the combiner after the impedance matching of completion common port is as shown in Figure 8.

Claims

1. combiner public port impedance matching methods; It is characterized in that: earlier through the optimization garden that disappears combiner multiport network coupled matrix; Obtain representing the coupled matrix of the coupled relation of coupling coefficient and port and resonator between each resonator, from this coupled matrix, can draw the coupling coefficient m of public port and adjacent each resonator _0,1– m _{0, i}Again according to FL-network comprehensive Design formula: Obtain the outside Q value of wave filter and the relation between the coupling coefficient, set up the relation of reflection group time delay and outside Q value.

2. a kind of combiner public port impedance matching methods according to claim 1; It is characterized in that: the relation of said reflection group time delay and outside Q value is established as: the value that calculates the reflection group time delay under the impedance matching state of realizing ideal through

; With the concrete implementation optimization Simulation of electromagnetic field simulation software to the impedance matching of combiner public port, the reflection group time delay value that emulation is obtained goes to approach and calculated value.

3. a combiner common port impedance matching structure is characterized in that: be to be linked to each other with the resonator of each passage by conductive material, link to each other with the public port of combiner through the aperture between last lower baffle plate.