A kind of substrate integrated form low passive intermodulation waveguide flange gasket
Technical field
The present invention relates to a kind of waveguide flange gaskets, belong to microwave technical field.
Background technique
Passive intermodulation (Passive Intermodulation, PIM) effect is the important interference of one of communication system
Phenomenon is widely present in various HIGH-POWERED MICROWAVES passive components and connection structure.In order to guarantee the normal work of communication system,
Effective passive intermodulation braking measure need to be taken.Generate passive intermodulation dominant mechanism be contact nonlinear and material nonlinearity,
Wherein material nonlinearity can by select suitable material avoid, and contact nonlinear be then prevalent in various microwaves without
In source structure.Waveguiding structure is one of structure type most widely used in various HIGH-POWERED MICROWAVES systems, and waveguide flange connects
Connecing is the primary factor that passive intermodulation is generated in waveguiding structure, and currently used standard waveguide flange uses physical connection mode,
The coupling part of flange can cause to contact due to the presence of many factors such as plating, roughness, dirty and material interface transition
It is non-linear, to generate passive intermodulation effect.
The current existing passive intermodulation braking measure for waveguide flange mainly has high pressure flange and deielectric-coating isolation side
Formula.High pressure flange is other than increasing press platform structure, it is also necessary to guarantee the sufficiently high finish of contact surface and the fastening of accurate torque, it is right
There is very high requirement in processing and assembling, and since there is contacts, contact nonlinear can not be inherently eliminated, existed
Long-term reliability problems.Deielectric-coating isolation method is not possible at present due to integrity problem in actual product.
In addition, presently, there are chokes (choke) formula flange, although avoiding a part of electrical contact, due to its master
Wanting structure is quarter-wave choke groove, cannot achieve broadband performance, bandwidth of operation is relatively narrow, is also restricted in practical application.
Patent " a kind of low passive intermodulation waveguide flange and design method " proposes the low passive intermodulation based on non-contact electromagnetic bandgap structure
Waveguide flange can effectively inhibit contact nonlinear, and bandwidth of operation is very wide.But the mentioned structure of the patent and method need
Change original waveguide flange structure, versatility is poor in practical applications, can correspondingly generate relatively high cost.Patent
" a kind of low passive intermodulation waveguide flange conversion equipment " is proposed low passive mutual based on metal double-side non-contact electromagnetic bandgap structure
Waveguide flange conversion equipment is adjusted, without changing original waveguide flange structure, the design of low passive intermodulation transition and conversion, tool can be realized
There is certain versatility.But the mentioned device of the patent is limited in low frequency applications, because with the reduction of frequency, it is periodically golden
The size for belonging to convex body structure is increase accordingly, and conventional criteria waveguide flange limited area can not arrange sufficient amount of metal convex body
Unit cannot achieve expected electromagnetic forbidden band characteristic, influence the normal transmission of electromagnetic wave.And the patent structure be difficult to realize it is small-sized
Lightweight.
Summary of the invention
Technical problem solved by the present invention is overcome the deficiencies in the prior art, proposes that a kind of substrate integrated form is low passive mutual
Adjust waveguide flange gasket, the transition connecting structure as conventional waveguide flange.Determine that critical feature size is joined by particular step
Number obtains suitable electromagnetic forbidden band characteristic, guarantees that electromagnetic field along waveguide normal transmission, can not be let out from air or dielectric gap
Dew, and then the metal face contact of conventional waveguide flanged joint is replaced, metal contact nonlinear is substantially eliminated, is realized low passive mutual
Tonality energy.Without changing former waveguide flange structure, the low passive intermodulation transition that conventional waveguide flange can be realized connects the present invention,
And small and light and high flexibility may be implemented by substrate integration mode, in low frequency to high-frequency range can be achieved with
The size of standard waveguide flange face matches.Low cost, general mass may be implemented, can be applied to various low passive intermodulation demands
HIGH-POWERED MICROWAVES component, in system and test macro.
The technical solution of the invention is as follows: a kind of substrate integrated form low passive intermodulation waveguide flange gasket, including two-sided
Periodical metal unit, dielectric substrate and plated-through hole;Waveguide transmission mouth and fixed hole, size are reserved on dielectric substrate
And position is consistent with corresponding standard waveguide flange;The two-sided periodical metal unit is plane patch structure, according to setting
Rule be arranged successively, be printed on the tow sides of dielectric substrate respectively using PCB printed circuit board technology;The front and back sides of dielectric substrate
It is connected between the corresponding two two-sided periodical metal units in upper position by plated-through hole.
The two-sided periodical metal unit is any regular shape, shape, size and arrangement side in the same plane
Formula is identical.
A kind of substrate integrated form low passive intermodulation waveguide flange gasket further includes that front outer media and reverse side outer layer are situated between
Matter, front outer media and reverse side outer media are adhered to the tow sides of dielectric substrate using multi-layer PCB technique respectively;Front
It is reserved with waveguide transmission mouth and fixed hole on outer media, reverse side outer media, size and location and corresponding standard waveguide
Flange is consistent.
The two-sided periodical size of metal unit, the thickness of dielectric substrate, the diameter of plated-through hole, front outer layer
The thickness of medium, the thickness of reverse side outer media are obtained by following steps:
Step 1: establishing single two-sided periodical metal unit simulation model in Electromagnetic Simulation program, two-sided week is set
Phase property metal unit, dielectric substrate, plated-through hole, front outer media, reverse side outer media material and dimensional parameters at the beginning of
Value is arranged periodic boundary condition, intrinsic Solution model is arranged;
Dispersion characteristics are obtained as a result, each size parameter values are adjusted, so that in dispersion characteristics Step 2: solving by characteristic value
Frequency forbidden band covering needed for working band range;
Step 3: establishing waveguide and the substrate integrated form in Electromagnetic Simulation program according to the size parameter values of acquisition
Whole simulation model after the connection of low passive intermodulation waveguide flange gasket construction;
Step 4: setting transimission power, according to the two-sided periodical metal unit quantity of transimission power size selection, to guarantee
Enough electromagnetic transmission rejections;
Step 5: emulation obtains insertion loss and stationary wave characteristic, dimensional parameters are adjusted, the Insertion Loss met the requirements is obtained and stays
Wave performance.
The dimensional parameters include the thickness of dielectric substrate, the size of two-sided periodical metal unit, adjacent two two-sided week
The spacing of phase property metal unit, the diameter of plated-through hole, the thickness of front outer media, reverse side outer media thickness.
A kind of substrate integrated form low passive intermodulation waveguide flange gasket, further includes lip block, dielectric substrate is arranged in
On tow sides, it is higher by dielectric substrate surface, forms the air gap, supporting pad between flange face when being mounted between waveguide flange
The installation site of block and the matching of corresponding standard waveguide flange face.
The two-sided periodical size of metal unit, the thickness of dielectric substrate, plated-through hole diameter and supporting pad
The thickness of block is obtained by following steps:
Step 1: establishing single two-sided periodical metal unit simulation model in Electromagnetic Simulation program, two-sided week is set
Periodic boundary is arranged in phase property metal unit, dielectric substrate, plated-through hole, the material of lip block and dimensional parameters initial value
Intrinsic Solution model is arranged in condition;
Dispersion characteristics are obtained as a result, each size parameter values are adjusted, so that in dispersion characteristics Step 2: solving by characteristic value
Frequency forbidden band covering needed for working band range;
Step 3: establishing waveguide and the substrate integrated form in Electromagnetic Simulation program according to the size parameter values of acquisition
Whole simulation model after the connection of low passive intermodulation waveguide flange gasket construction;
Step 4: setting transimission power, according to the two-sided periodical metal unit quantity of transimission power size selection, to guarantee
Enough electromagnetic transmission rejections;
Step 5: emulation obtains insertion loss and stationary wave characteristic, dimensional parameters are adjusted, the Insertion Loss met the requirements is obtained and stays
Wave performance.
The dimensional parameters include the thickness of dielectric substrate, the size of two-sided periodical metal unit, adjacent two two-sided week
The spacing of phase property metal unit, the diameter of plated-through hole, lip block thickness.
The advantages of the present invention over the prior art are that:
(1) present invention is by the two-sided periodical metal unit array of construction substrate integrated form, in conjunction with outer layer support construction,
Two-sided air or dielectric gap are constituted between conventional waveguide flange contacts transition connecting structure without metal, passes through electromagnetic forbidden band
Characteristic hinders electromagnetic field leakage, and instead of the metal face contact of conventional waveguide flanged joint, it is non-substantially to eliminate metal contact
Linearly, low passive intermodulation performance is realized.
(2) compared with prior art, have no need to change conventional waveguide flange arrangement can be realized low passive intermodulation mistake to the present invention
Connection is crossed, the requirement to conventional waveguide flange surface treatment process and assembly technology is reduced, there is preferable versatility, and have
There is the wide working characteristics of all-wave conduction band.
(3) compared with prior art, small and light and high flexibility may be implemented by substrate integration mode in the present invention,
It can be achieved to match with the size of standard waveguide flange face in low frequency to high-frequency range.Low cost, general batch may be implemented
Change.
Detailed description of the invention
Fig. 1 a is the STRUCTURE DECOMPOSITION of the dielectric gap structure of substrate integrated form low passive intermodulation waveguide flange gasket of the present invention
Schematic diagram;
Fig. 1 b is the overall structure of the dielectric gap structure of substrate integrated form low passive intermodulation waveguide flange gasket of the present invention
Schematic diagram and side view;
Fig. 1 c is the overall structure of the air gap structure of substrate integrated form low passive intermodulation waveguide flange gasket of the present invention
Schematic diagram;
Fig. 1 d is the overall structure of the air gap structure of substrate integrated form low passive intermodulation waveguide flange gasket of the present invention
Side view;
Fig. 2 is that the individual unit of two-sided periodical metal unit array in substrate integrated form flange gasket of the present invention emulates meter
Calculate model schematic;
Fig. 3 is substrate integrated form low passive intermodulation waveguide flange gasket of the present invention to match Ku frequency range BJ120 (WR75)
Standard waveguide flange, using in implementation process for the identical dielectric gap structure of front and back sides outer media thickness, square is double
The dispersion characteristics simulation curve figure of face periodicity metal unit;
Fig. 4 is the flange gasket for designing matching Ku frequency range BJ120 (WR75) standard waveguide flange of realization according to the present invention
Actual measurement standing wave and insertion loss performance map;
Fig. 5 is the flange gasket for designing matching Ku frequency range BJ120 (WR75) standard waveguide flange of realization according to the present invention
Actual measurement passive intermodulation result figure.
Specific embodiment
A specific embodiment of the invention is further described in detail with reference to the accompanying drawing:
The present invention proposes a kind of substrate integrated form low passive intermodulation waveguide flange gasket, passes through the double of construction substrate integrated form
Face periodicity metal unit array is constituted between two-sided air or medium in conjunction with outer layer support construction between conventional waveguide flange
Gap contacts transition connecting structure without metal.Critical feature size parameter is determined by particular step, is obtained suitable electromagnetism and is prohibited
Band characteristic guarantees that electromagnetic field along waveguide normal transmission, can not be revealed from air or dielectric gap, and then replaces conventional wave inducing defecation by enema and suppository
The metal face contact of orchid connection, substantially eliminates metal contact nonlinear, realizes low passive intermodulation performance.The mentioned gasket of the present invention
Without changing former waveguide flange structure the low passive intermodulation transition connection of conventional waveguide flange can be realized, and pass through base in structure
Small and light and high flexibility may be implemented in piece integration mode, the achievable and standard waveguide in low frequency to high-frequency range
The size of flange face matches.Low cost, general mass may be implemented, can be applied to the high-power of various low passive intermodulation demands
In microwave component, system and test macro.
As shown in figs. la-ld, a kind of substrate integrated form low passive intermodulation waveguide flange gasket, main structure includes two-sided
Periodical metal unit 1, dielectric substrate 2 and plated-through hole 3.Waveguide transmission mouth and fixed hole, size are reserved on gasket
And position is consistent with corresponding standard waveguide flange.
Two-sided periodicity metal unit 1 is plane patch structure, and thickness is unlimited, according to certain regularly arranged, using PCB
Printed circuit board technology is printed on the tow sides of dielectric substrate 2 respectively.Two-sided periodicity metal unit 1 passes through 3 phase of plated-through hole
Connection.
Two-sided periodicity 1 shape of metal unit is not fixed, and can be square, any regulars shape such as rectangle, circle,
Shape, size and arrangement mode in same plane is identical.
The material of dielectric substrate 2 is unlimited.
A kind of preferred mode is dielectric gap structure, further includes front outer media 4 and reverse side outer media 5, can adopt
It is adhered to the tow sides of dielectric substrate 2 respectively with multi-layer PCB technique, constitutes the substrate integrated form low passive intermodulation of dielectric gap
Waveguide flange gasket.The material of front outer media 4 and reverse side outer media 5 is unlimited.
Another preferred mode is air gap structure, further includes lip block 6, and the substrate for constituting the air gap is integrated
Formula low passive intermodulation waveguide flange gasket.
The material and shape of lip block 6 do not limit, and installation site needs and the matching of corresponding standard waveguide flange face.
Two-sided the periodicity size of metal unit 1, the thickness of dielectric substrate 2, the diameter of plated-through hole 3, front outer layer
The parameters such as the thickness of the thickness of medium 4, the thickness of reverse side outer media 5 and lip block 6 do not have unique value, pass through following steps
Obtain suitably sized value:
(1) two-sided periodical metal unit battle array in substrate integrated form flange gasket of the present invention is established in Electromagnetic Simulation program
Each section material and dimensional parameters initial value is arranged in the individual unit simulation model of column, and periodic boundary condition is arranged, and is arranged intrinsic
Solution model.
(2) it is solved by characteristic value and obtains dispersion characteristics as a result, each size parameter values are adjusted, so that the frequency in dispersion characteristics
Working band range needed for the covering of rate forbidden band.
(3) according to the size parameter values of acquisition, common waveguide and flange gasket of the present invention are established in Electromagnetic Simulation program
Whole simulation model after structure connection.
(4) transimission power is set, it is enough to guarantee according to the two-sided periodical metal unit quantity of transimission power size selection
Electromagnetic transmission rejection.
(5) emulation obtains insertion loss and stationary wave characteristic, inching parameter, obtains the Insertion Loss and standing wave performance of satisfaction.
To match Ku frequency range BJ120 (WR75) standard waveguide flange (9.84~15GHz of bandwidth of operation), front and back sides outer layer is situated between
Matter thickness is identical, for the dielectric gap structure flanges gasket of the two-sided periodical metal unit of square, illustrates tool of the invention
Body implementation process:
(1) list of two-sided periodicity metal unit array in substrate integrated form flange gasket is established in Electromagnetic Simulation program
A unit simulation model, as shown in Fig. 2, dielectric substrate 2 is with a thickness of hp, two-sided periodicity 1 width of metal unit is w, periodically
1 two-dimensional directional spacing of metal unit is g, and 3 diameter of plated-through hole is d, front outer media 4,5 thickness of reverse side outer media
It is ha.Dielectric substrate 2 and front and back sides outer media select FR4 dielectric substrate material.Each dimensional parameters initial value is set, is arranged
Intrinsic Solution model is arranged in periodic boundary condition, solves dispersion characteristics.
(2) dimensional parameters are adjusted, suitable dispersion characteristics figure is obtained.Work as hp=1.5mm, ha=0.2mm, w=1.9mm, g
When=0.1mm, d=0.4mm, dispersion characteristics as shown in figure 3, electromagnetic forbidden band covering BJ120 waveguide needed for working frequency range range,
It meets the requirements.
(3) entirety that standard BJ120 waveguide is connected with the present embodiment gasket construction is established according to the dimensional parameters of acquisition to imitate
True mode selects 7 row's periodicity metal unit 1 of the face E direction, 4 row's periodicity metal unit 1 of the face H direction.
(4) setting port power is 100W, simulated electric field distribution character.Electromagnetic field be tied to inside structure of the invention and
It will not reveal, therefore periodical metal unit quantity selection is suitable.
(5) emulation obtains S parameter, according to practical PCB parameter, inching parameter, the size after fine tuning are as follows: hp=
1.53mm,ha=0.2mm, w=1.9mm, g=0.1mm, d=0.4mm.The S parameter characteristic met is obtained, the S ginseng of satisfaction is obtained
Number characteristic, it is desirable that in entire waveguide work bandwidth, standing wave and insertion loss performance are able to satisfy engineering application requirement.
(6) processing is in kind, tests its standing wave and insertion loss performance, as shown in Figure 4.
In the microwave component and test macro required present invention can apply to various high-power low passive intermodulations, without changing
Original waveguide flange structure can be realized low passive intermodulation transition under conditions of not influencing electromagnetic transmission performance and connect
It connects, and there is stable low passive intermodulation performance and very wide bandwidth of operation.It may be implemented simultaneously by substrate integration mode small
Type is lightening and high flexibility, can be achieved to match with the size of standard waveguide flange face in low frequency to high-frequency range.It can
To realize low cost, general mass, it is widely used value in microwave high power technology field.
The mentioned method of the present invention realizes the flange gasket of matching Ku frequency range BJ120 (WR75) standard waveguide flange by design
Realize verifying.3 ranks have been carried out to the low passive intermodulation waveguide flange gasket realized according to the present invention and 5 ranks are reflective passive
Intermodulation testing experiment, tests 3 ranks, and carrier frequency is 11.4GHz and 12.75GHz, and passive intermodulation frequency is 14.1GHz.It is right
It is tested in 5 ranks, carrier frequency is 12GHz and 12.75GHz, and passive intermodulation frequency is 14.25GHz.It carries out under different measured powers
PIM test, 5~100W of single-path testing carrier power.The measurement result of practical passive intermodulation is as shown in figure 5, work as common waveguide
After increasing gasket construction of the present invention between flange, passive intermodulation level is greatly reduced, close to the remaining intermodulation level of system, to nothing
The average degree of suppression of source intermodulation has reached 20dB or more, and maximum inhibition degree is more than 40dB.Test result shows the mentioned base of the present invention
Piece integrated form low passive intermodulation waveguide flange gasket can effectively realize the low passive intermodulation transition between conventional waveguide flange
Connection.
The content that description in the present invention is not described in detail belongs to the well-known technique of professional and technical personnel in the field.