CN108933320A - A kind of coupler circuit - Google Patents
A kind of coupler circuit Download PDFInfo
- Publication number
- CN108933320A CN108933320A CN201710386869.8A CN201710386869A CN108933320A CN 108933320 A CN108933320 A CN 108933320A CN 201710386869 A CN201710386869 A CN 201710386869A CN 108933320 A CN108933320 A CN 108933320A
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- China
- Prior art keywords
- bypass
- admittance
- line
- network
- microstrip line
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
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Classifications
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P5/00—Coupling devices of the waveguide type
- H01P5/12—Coupling devices having more than two ports
- H01P5/16—Conjugate devices, i.e. devices having at least one port decoupled from one other port
- H01P5/18—Conjugate devices, i.e. devices having at least one port decoupled from one other port consisting of two coupled guides, e.g. directional couplers
- H01P5/184—Conjugate devices, i.e. devices having at least one port decoupled from one other port consisting of two coupled guides, e.g. directional couplers the guides being strip lines or microstrips
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- Cable Transmission Systems, Equalization Of Radio And Reduction Of Echo (AREA)
Abstract
The present invention provides a kind of coupler circuits, the circuit includes signal end, transmission line and bypass admittance network, wherein, it bypasses admittance network and transmission line forms local unit, the electrical parameter of local unit and the target electrical parameter of coupler circuit are equivalent, which is compared with only providing transmission line and reaching the mode of identical electrical parameter, transmission line area (being mainly reflected in length) will greatly reduce, and then the integral layout area of coupler circuit can be reduced, solve the problems, such as that layout area existing for existing coupler circuit is larger.
Description
Technical field
The present invention relates to the communications field more particularly to a kind of coupler circuits.
Background technique
With the development of communication technology, the miniaturization of wireless product becomes trend, and cost factor also becomes product competitiveness
Be primarily upon factor.Microstrip directional coupler in cost compared to lead at this stage ceramic component to be used have it is absolute at
This advantage, indicator consilience is good, and still, existing microstrip directional coupler at least has the disadvantage that:Directional coupler bandwidth
Relatively narrow, for high-frequency circuit, the length of this frequency range quatrter-wavelength line is too long, leads to coupler integral layout occupied area
It is too big.
Summary of the invention
The embodiment of the invention provides a kind of coupler circuits, at least to solve range of distribution existing for existing coupler circuit
The larger problem of product.
To solve the above-mentioned problems, the present invention provides a kind of coupler circuits, including:It is used to form a plurality of biography of loop
Defeated line, the signal end connecting with transmission line and the bypass admittance network connecting with transmission line bypass admittance network and transmission line
Local unit is formed, the electrical parameter of local unit and the target electrical parameter of coupler circuit are equivalent.
The beneficial effect of the embodiment of the present invention:
The embodiment of the invention provides a kind of coupler circuit, which includes signal end, transmission line and bypass admittance net
Network, wherein bypass admittance network and transmission line form local unit, the electrical parameter of local unit and the target electricity of coupler circuit
Parameter equivalent, for which compared with only providing transmission line and reaching the mode of identical electrical parameter, transmission line area (is mainly reflected in length
On degree) it will greatly reduce, and then the integral layout area of coupler circuit can be reduced, it solves existing coupler circuit and deposits
The larger problem of layout area.
Detailed description of the invention
Fig. 1 is the structural schematic diagram for the coupler circuit that first embodiment of the invention provides;
Fig. 2 is the circuit diagram for the existing coupler circuit that second embodiment of the invention is related to;
Fig. 3 is the first circuit diagram for the coupler circuit that second embodiment of the invention provides;
Fig. 4 is second of circuit diagram of the coupler circuit that second embodiment of the invention provides;
Fig. 5 is the coupler circuit of the present invention layout and existing coupler circuit layout that second embodiment of the invention is related to
Contrast schematic diagram.
Specific embodiment
Following will be combined with the drawings in the embodiments of the present invention, and technical solution in the embodiment of the present invention carries out clear, complete
Site preparation description, it is clear that described embodiment is a part of the embodiment in the present invention, instead of all the embodiments.It is based on
Embodiment in the present invention, it is obtained by those of ordinary skill in the art without making creative efforts every other
Embodiment shall fall within the protection scope of the present invention.
Further annotation explanation now is made to the present invention by way of specific embodiment combination attached drawing.
First embodiment:
Fig. 1 is the structural schematic diagram for the coupler circuit that first embodiment of the invention provides, as shown in Figure 1, the present embodiment
The coupler circuit of offer includes:The plurality of transmission lines 11 for being used to form loop, signal end 12, the Yi Jiyu being connect with transmission line
The bypass admittance network 13 of transmission line connection, bypass admittance network 13 and transmission line 11 form local unit, the electricity of local unit
Parameter and the target electrical parameter of coupler circuit 1 are equivalent.
In practical applications, transmission line can be realized using various ways, it is preferred that as shown in figure 3, in some implementations
In example, the transmission line 11 in above-described embodiment is microstrip line.
In some embodiments, the signal end in above-described embodiment is connected in the connecting node of adjacent transmission lines.
As shown in figure 4, in some embodiments, the transmission line in above-described embodiment is impedance transformation line.
In some embodiments, the signal end in above-described embodiment connects on the transmission line.
As shown in Fig. 3 or Fig. 4, in some embodiments, the bypass admittance network in above-described embodiment is arranged in loop
In the interior zone of formation.
As shown in figure 5, in some embodiments, the coupler circuit setting in above-described embodiment is transmitted on circuit boards
Line, signal end, bypass admittance network, are arranged in the cabling face of circuit board, the ground plane of circuit board in such a way that cabling is realized
The region of corresponding bypass admittance network is arranged for defect, and other positions are ground connection setting.
As shown in figure 5, in some embodiments, the bypass admittance network in above-described embodiment includes micro-strip sector minor matters,
The center of circle fixed point of micro-strip sector minor matters is connect with transmission line, arc-shaped side and straight line open circuit.
In practical applications, electrical parameter includes admittance, and target electrical parameter includes main line admittance and branch line admittance;Such as Fig. 3 or
Shown in person Fig. 4, in some embodiments, the microstrip line in above-described embodiment is micro- including the first microstrip line, the second microstrip line, third
Band line, the 4th microstrip line, the first microstrip line and the second microstrip line are as main line, and third microstrip line, the 4th microstrip line are as branch line;
First microstrip line, the second microstrip line, third microstrip line, the 4th microstrip line form first partial list with bypass admittance network respectively
Member, the second local unit, third local unit, the 4th local unit, the admittance of first partial unit, the second local unit are led
Receive equivalent with main line admittance, the admittance of third local unit, the admittance of the 4th local unit and branch line admittance are equivalent.
As shown in Fig. 3 or Fig. 4, in some embodiments, the bypass admittance network in above-described embodiment includes by the of first
Road admittance network, the second bypass admittance network, third bypass admittance network, the 4th bypass admittance network, the first bypass admittance net
Network is connect with the first microstrip line with the connecting node of third microstrip line, and the second bypass admittance network and the first microstrip line and the 4th are micro-
Connecting node connection with line, third bypass admittance network are connect with the second microstrip line with the connecting node of third microstrip line, the
Four bypass admittance networks are connect with the second microstrip line with the connecting node of the 4th microstrip line;First microstrip line, the first bypass admittance
Network and the second bypass admittance network form first partial unit;Second microstrip line, third bypass admittance network and the 4th bypass
Admittance network forms the second local unit;Third microstrip line, the first bypass admittance network and third bypass admittance network form the
Three local units;4th microstrip line, the second bypass admittance network and the 4th bypass admittance network form the 4th local unit.
Present embodiments provide a kind of coupler circuit, the circuit include signal end, transmission line and bypass admittance network,
In, bypass admittance network and transmission line form local unit, the electrical parameter of local unit and the target electrical parameter of coupler circuit
Equivalent, for which compared with only providing transmission line and reaching the mode of identical electrical parameter, transmission line area (is mainly reflected in length
On) will greatly reduce, and then the integral layout area of coupler circuit can be reduced, it solves existing coupler circuit and exists
The larger problem of layout area.
Further annotation explanation is done to the present invention now in conjunction with concrete application scene.
Second embodiment:
The present embodiment provides a kind of novel coupler circuits for having bypass admittance network loading structure, to realize micro-strip
The miniaturization of directional coupler and performance optimization.
Existing coupler circuit is as shown in Fig. 2, 50 Europe of main line impedance, 35.35 Europe of branch line impedence.When signal is defeated from port 1
Fashionable, signal is exported from 2,3 port constant powers, is isolation end without output on 4 port theories.Main line, leg length are all λ/4
(λ is center phase wavelength).It is assumed that signal is inputted from port 1, the signal voltage to port 4 is just made of two components, a routing A
To C, a routing A is by B, D to C, and two-way phase difference is 180 degree, as long as requiring the amplitude of two voltages is equal to ensure that end
Mouth 4 is without output power.And two component of voltage of port 3 then pass through A and reach through B to D and A through two paths of C to D, two paths
Equal length, component of voltage are superimposed output in the same direction.
But with the development of communication technology, the broadband of wireless product, miniaturization become trend, and cost factor also becomes
Product competitiveness is primarily upon factor.Microstrip directional coupler is in cost compared to leading ceramic component to be used at this stage
There is absolute cost advantage, indicator consilience is good, therefore other than bandwidth broadning, index optimization etc., Miniaturization Design becomes master
Want focus.
A kind of Miniaturization Design scheme of microstrip directional coupler is present embodiments provided, and can be promoted on its basis
Coupler bandwidth and high-frequency suppressing performance.
When the transmission line of coupler circuit provided in this embodiment is realized using microstrip line, as shown in Figure 3:
Admittance network loaded microstrip directional coupler design scheme is bypassed, is realized using the π type loading structure of deformation any
50 ohmage lines of phase shift.It is loaded with inside coupler by setting on the basis of conventional microstrip directional coupler framework
Four bypass admittance networks of meter compared with the existing branch line directional coupler circuit structure shown in Fig. 2, are realized in new structure
?:
The local unit that optimization main line 05 and bypass admittance network 01, bypass admittance network 02 form is equivalent to prototype structure
In main line 01;
The local unit that optimization main line 06 and bypass admittance network 03, bypass admittance network 04 form is equivalent to prototype structure
In main line 02;
The local unit that optimization branch line 07 and bypass admittance network 01, bypass admittance network 03 form is equivalent to prototype structure
In branch line 03;
The local unit that optimization branch line 08 and bypass admittance network 02, bypass admittance network 04 form is equivalent to prototype structure
In branch line 04;
In practical layout, each interstructural connection type is:
Optimization main line 05, optimization branch line 08, optimization main line 06, the optimization first place clockwise of branch line 07 connect and compose closure knot
Structure;
Bypass admittance network 01 is connected to optimization main line 05, optimization 07 intersection of branch line;
Bypass admittance network 02 is connected to optimization main line 05, optimization 08 intersection of branch line;
Bypass admittance network 03 is connected to optimization main line 06, optimization 07 intersection of branch line;
Bypass admittance network 04 is connected to optimization main line 06, optimization 08 intersection of branch line;
The length for optimizing main line 05,06 and optimizing the realization of branch line 07,08 is corresponding much smaller than in conventional coupler structure
Main line 01,02 and branch line 03,04.Coupler integral layout area is greatly reduced based on this, realizes its miniaturization.Together
When, since novel directional coupler structure has broken the limitation of main line and the electrical length of branch line λ/4, it can be achieved that orienting compared to tradition
The more excellent broadband character of coupler.And high-frequency harmonic is provided and is effectively inhibited.
When the transmission line of coupler circuit provided in this embodiment is realized using impedance transformation line, as shown in Figure 4:
Admittance network loaded microstrip directional coupler design scheme is bypassed, is realized using the π type loading structure of deformation any
50 ohmage lines of phase shift.It is loaded with inside coupler by setting on the basis of conventional microstrip directional coupler framework
Four bypass admittance networks of meter compared with the existing branch line directional coupler circuit structure shown in Fig. 2, are realized in new structure
?:
The local unit that optimization main line 05 and bypass admittance network 01, bypass admittance network 02 form is equivalent to prototype structure
In main line 01;
The local unit that optimization main line 06 and bypass admittance network 03, bypass admittance network 04 form is equivalent to prototype structure
In main line 02;
The local unit that optimization branch line 07 and bypass admittance network 01, bypass admittance network 03 form is equivalent to prototype structure
In branch line 03;
The local unit that optimization branch line 08 and bypass admittance network 02, bypass admittance network 04 form is equivalent to prototype structure
In branch line 04;
In practical layout, each interstructural connection type is:
Optimization main line 05, optimization branch line 08, optimization main line 06, the optimization first place clockwise of branch line 07 connect and compose closure knot
Structure;
Bypass admittance network 01 is connected to optimization main line 05, optimization 07 intersection of branch line;
Bypass admittance network 02 is connected to optimization main line 05, optimization 08 intersection of branch line;
Bypass admittance network 03 is connected to optimization main line 06, optimization 07 intersection of branch line;
Bypass admittance network 04 is connected to optimization main line 06, optimization 08 intersection of branch line;
The length for optimizing main line 05,06 and optimizing the realization of branch line 07,08 is corresponding much smaller than in conventional coupler structure
Main line 01,02 and branch line 03,04.Coupler integral layout area is greatly reduced based on this, realizes its miniaturization.Together
When, since novel directional coupler structure has broken the limitation of main line and the electrical length of branch line λ/4, it can be achieved that orienting compared to tradition
The more excellent broadband character of coupler.And high-frequency harmonic is provided and is effectively inhibited.
In practical applications, bypass admittance load networks way of realization include but is not limited to abnormity open circuit minor matters load,
The forms such as defect ground structure load, as shown in Figure 5.
Fig. 5 illustrates coupler circuit provided by the invention and existing coupler electricity by taking 2G frequency range directional coupler as an example
Layout designs contrast schematic diagram of the road on pcb board.For 50 Ohms systems, the minor matters in parallel equivalent 50 of major-minor line and its two sides
The quarter-wave transmission line of ohm, branch line and equivalent 35.35 ohm of the quarter-wave of the minor matters in parallel of its two sides
Transmission line, the minor matters in parallel of two neighboring transmission line use the special fan-shaped minor matters with new admittance value to replace, and admittance value is equivalent
In the sum of former two minor matters admittance, a kind of final microstrip directional coupler based on bypass admittance network, the sector minor matters are realized
Lower section use defect ground structure, micro-strip sector minor matters, PCB medium and the entire bypass admittance network of defect ground structure composition.
As shown in Figure 5, directional coupler provided by the invention, which designs, can be achieved small form factor requirements, and emulation shows realizing one
On the basis of determining high-frequency suppressing, bandwidth optimization, coupler circuit provided by the invention is than existing coupler circuit in design layout
Optimization is more than 40% in size;Meanwhile broadband performance is improved to a certain extent, and the design is compared with traditional directional couple
Device has better high-frequency suppressing.
Coupler circuit provided in this embodiment is low in cost, and relative to conventional microstrip coupler scheme, cost is hardly
Become;And cost is well below same index ceramic component;Framework is simple, it can be achieved that directional couple function in frequency range, expands passband
Bandwidth;It may be implemented greatly to reduce coupler layout area on the basis of band characteristic, realize its miniaturization;Relative to existing micro-
Band coupler scheme, there is better high-frequency suppressing characteristic.
In summary, at least there is following beneficial effect in implementation through the embodiment of the present invention:
The embodiment of the invention provides a kind of coupler circuit, which includes signal end, transmission line and bypass admittance net
Network, wherein bypass admittance network and transmission line form local unit, the electrical parameter of local unit and the target electricity of coupler circuit
Parameter equivalent, for which compared with only providing transmission line and reaching the mode of identical electrical parameter, transmission line area (is mainly reflected in length
On degree) it will greatly reduce, and then the integral layout area of coupler circuit can be reduced, it solves existing coupler circuit and deposits
The larger problem of layout area.
The above is only a specific embodiment of the invention, not do limitation in any form to the present invention, all
Any simple modification, equivalent variations, combination or the modification that embodiment of above is made according to the technical essence of the invention, still
Belong to the protection scope of technical solution of the present invention.
Claims (10)
1. a kind of coupler circuit, including:The plurality of transmission lines for being used to form loop, the signal end being connect with the transmission line,
And the bypass admittance network connecting with the transmission line, the bypass admittance network and the transmission line form local unit,
The electrical parameter of the local unit and the target electrical parameter of the coupler circuit are equivalent.
2. coupler circuit as described in claim 1, which is characterized in that the transmission line is microstrip line.
3. coupler circuit as claimed in claim 2, which is characterized in that the signal end is connected to the connection of adjacent transmission lines
On node.
4. coupler circuit as described in claim 1, which is characterized in that the transmission line is impedance transformation line.
5. coupler circuit as claimed in claim 4, which is characterized in that the signal end connection is on the transmission line.
6. coupler circuit as described in claim 1, which is characterized in that the bypass admittance network is arranged in the loop shape
At interior zone in.
7. coupler circuit as described in claim 1, which is characterized in that the coupler circuit is arranged on circuit boards, institute
Transmission line, signal end, bypass admittance network are stated, the cabling face of the circuit board is set in such a way that cabling is realized, it is described
The region that the ground plane of circuit board corresponds to the bypass admittance network is arranged for defect, and other positions are ground connection setting.
8. coupler circuit as described in claim 1, which is characterized in that the bypass admittance network includes micro-strip sector branch
The center of circle fixed point of section, the micro-strip sector minor matters is connect with the transmission line, arc-shaped side and straight line open circuit.
9. coupler circuit as claimed in any one of claims 1 to 8, which is characterized in that the electrical parameter includes admittance, described
Target electrical parameter includes main line admittance and branch line admittance;The microstrip line includes the first microstrip line, the second microstrip line, third micro-strip
Line, the 4th microstrip line, first microstrip line and the second microstrip line are made as main line, the third microstrip line, the 4th microstrip line
For branch line;First microstrip line, the second microstrip line, third microstrip line, the 4th microstrip line respectively with the bypass admittance network
First partial unit, the second local unit, third local unit, the 4th local unit are formed, the first partial unit is led
Receive, the admittance of the second local unit and the main line admittance it is equivalent, the admittance of the third local unit, the 4th local unit
Admittance and the branch line admittance are equivalent.
10. coupler circuit as claimed in claim 9, which is characterized in that the bypass admittance network includes that the first bypass is led
Receive network, second bypass admittance network, third bypass admittance network, the 4th bypass admittance network, it is described first bypass admittance net
Network is connect with first microstrip line with the connecting node of third microstrip line, the second bypass admittance network and described first micro-
It is connect with line with the connecting node of the 4th microstrip line, the third bypass admittance network and second microstrip line and third micro-strip
The connecting node of line connects, the connecting node company of the 4th bypass admittance network and second microstrip line and the 4th microstrip line
It connects;First microstrip line, the first bypass admittance network and the second bypass admittance network form the first partial
Unit;Second microstrip line, third bypass admittance network and the 4th bypass admittance network form the second game
Portion's unit;The third microstrip line, the first bypass admittance network and third bypass admittance network form the third
Local unit;4th microstrip line, the second bypass admittance network and the 4th bypass admittance network form described the
Four local units.
Priority Applications (1)
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CN201710386869.8A CN108933320A (en) | 2017-05-26 | 2017-05-26 | A kind of coupler circuit |
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CN201710386869.8A CN108933320A (en) | 2017-05-26 | 2017-05-26 | A kind of coupler circuit |
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Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN201134494Y (en) * | 2007-12-27 | 2008-10-15 | 奥雷通光通讯设备(上海)有限公司 | Strong coupling device with defect structure |
CN202662766U (en) * | 2012-04-26 | 2013-01-09 | 安徽科瑞达通信科技有限公司 | Novel high-isolation low-intermodulation co-frequent combiner |
KR20130064600A (en) * | 2011-12-08 | 2013-06-18 | 한국전자통신연구원 | Miniature band pass filter of channels of ultra-wideband using multiple rings generating phase differences |
CN104091992A (en) * | 2014-07-17 | 2014-10-08 | 东南大学 | Compact type double-frequency stub coupler based on substrate integrated coaxial line technology |
-
2017
- 2017-05-26 CN CN201710386869.8A patent/CN108933320A/en not_active Withdrawn
Patent Citations (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN201134494Y (en) * | 2007-12-27 | 2008-10-15 | 奥雷通光通讯设备(上海)有限公司 | Strong coupling device with defect structure |
KR20130064600A (en) * | 2011-12-08 | 2013-06-18 | 한국전자통신연구원 | Miniature band pass filter of channels of ultra-wideband using multiple rings generating phase differences |
CN202662766U (en) * | 2012-04-26 | 2013-01-09 | 安徽科瑞达通信科技有限公司 | Novel high-isolation low-intermodulation co-frequent combiner |
CN104091992A (en) * | 2014-07-17 | 2014-10-08 | 东南大学 | Compact type double-frequency stub coupler based on substrate integrated coaxial line technology |
Non-Patent Citations (1)
Title |
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CHON CHIO LEONG等: ""A tunable dual-band DGS stub tapped branch-line coupler"", 《2010 ASIA-PACIFIC MICROWAVE CONFERENCE》 * |
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Application publication date: 20181204 |