CN204205018U - A kind of electric adjusting power distributor with filter function - Google Patents
A kind of electric adjusting power distributor with filter function Download PDFInfo
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- CN204205018U CN204205018U CN201420740449.7U CN201420740449U CN204205018U CN 204205018 U CN204205018 U CN 204205018U CN 201420740449 U CN201420740449 U CN 201420740449U CN 204205018 U CN204205018 U CN 204205018U
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- microstrip line
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Abstract
The utility model proposes a kind of electric adjusting power distributor with filter function, its whole circuit structure is symmetrical, and achieving power-division ratios is 1:1; Two pairs of quarter-wave resonance devices intercoupled define two filter networks, achieve the characteristic of bandpass filtering; Resistance achieves the coupling of 3 ports of circuit and the isolation of two output ports; The variable capacitance diode loaded, adopts the on-load voltage changing di-cap to regulate the electrical length of resonator and feed line, achieves regulable center frequency; In addition, the source load coupling of utilization introduces three transmission zeros, and make the utility model not only have very high selectivity, stopband inhibition is also fine.
Description
Technical field
The utility model relates to a kind of electric adjusting power distributor with filter function, and the electricity being integrated with band-pass filtering function that particularly can be applicable to radio-frequency (RF) front-end circuit adjusts equal power.
Background technology
In mobile communication, satellite communication, wireless sensing net node and wearable wireless device, need reduce equipment volume or in the confined space, hold more functional module, therefore miniaturization is the inexorable trend of development.Volume due to radio-frequency front-end occupies a part very large in wireless device, carries out further investigation to its miniaturization, has important theory significance and using value.
The Miniaturization Research of past radio frequency device is with the performance boost of single components and parts and small-sizedly turn to master.Through research and probe in recent years, the degree that current device volume reduces has been difficult to continue to improve, and enters bottleneck.For overcoming this problem, adopting the mode of many devices collaborative design that multiple device is integrated into a device, making a device have several functions, thus it is miniaturized to reduce number of devices realization.
Power divider has the function of distribution/composite signal, all will use in a lot of aerial array and balancing circuitry, is a basic microwave circuit.And bandwidth-limited circuit can isolate the function of required frequency band, it is also another kind of indispensable assembly in wireless communication system.These two kinds of elements often coexist in system, are therefore subject to the extensive concern of scholars.In filter and power divider Integration Design, integrate and mainly contain following methods: 1) filter circuit and merit parallel circuit are merged and make it have two kinds of functions; 2) quarter-wave transmission line in power divider is replaced with filter circuit.Designed circuit has filtered power distributor, filter couplers and filtering hybrid ring etc., not only obtain good electrical properties, and volume is little.
Although Chinese scholars starts to pay attention to this direction and done some to explore, this direction is just in the starting stage at present, faces the challenge.And in adjustable filter circuit, Normal practice the non-adjustable assembly in many pass-bands system is changed into adjustable component, existing a lot of achievement in research, but the open source literature with the adjustable power distributor of filter function is also fewer.At document " S. Kim, and J. Jeong, " Reconfigurable 1:3 power divider using coupled lines, "
electron. Lett., vol. 45, no. 22, pp. 1141 – 1143, Oct. 2009. ", " H.-S. Tae, K.-S. Oh, H.-L. Lee, W.-I. Son, and J.-W. Yu, " Reconfigurable 1 × 4 power divider with switched impedance matching circuits, "
iEEE Microw. Wireless. Compon. Lett., vol. 22, no. 2, pp. 64 – 66, Feb. 2012. " and " E. Lourandakis, M. Schmidt, S. Seitz, and R. Weigel, " Reduced size frequency agile microwave circuits using ferroelectric thin-film varactors, "
iEEE Trans. Microw. Theory Tech., vol. 56, no. 12, pp. 3093 – 3099, June. 2008. ", adopt switch and variable capacitance diode to carry out the equiva lent impedance of controls transfer line, to obtain different merit proportion by subtraction, realize the output port number of adjustable switch, to adopt variable capacitance diode to realize frequency-adjustable, adjustable component only has power dividing function.According to investigation, also there is not the open report of the adjustable power distributor aspect of band filter function at present, therefore, the utility model proposes a kind of electricity being integrated with band-pass filtering function and adjust equal power.
Utility model content
The purpose of this utility model is to overcome prior art above shortcomings, proposes a kind of adjustable equal power being integrated with band-pass filtering function.In the utility model, whole circuit structure is symmetrical, and achieving power-division ratios is 1:1; Two pairs of quarter-wave resonance devices intercoupled define two filter networks, achieve the characteristic of bandpass filtering; Resistance achieves the coupling of 3 ports of circuit and the isolation of two output ports; The variable capacitance diode loaded, adopts the on-load voltage changing di-cap to regulate the electrical length of resonator and feed line, achieves regulable center frequency; In addition, the source load coupling of utilization introduces three transmission zeros, and make the utility model not only have very high selectivity, stopband inhibition is also fine.
The purpose of this utility model realizes one of at least by following technical solution.
A kind of electric adjusting power distributor with filter function, comprise upper-layer micro-strip structure, isolation resistance, loading capacitance, loading variable capacitance diode, intermediate medium substrate and underlying metal floor, upper-layer micro-strip structure is attached to the upper surface of intermediate medium substrate, and intermediate medium base lower surface is underlying metal floor; It is characterized in that: described upper-layer micro-strip structure comprises four resonators, three feed lines and three ports, and be arranged into laterally zygomorphic two bandwidth-limited circuits; The bandwidth-limited circuit being arranged in top is made up of the first half of described three feed line first feed lines and the second feed line and described four resonator first resonators and the second resonator; Wherein the first half of the first feed line is the microstrip line that the first microstrip line, the second microstrip line, the 3rd microstrip line and the 4th microstrip line connected successively is formed; Second feed line is the microstrip line that the 5th microstrip line, the 6th microstrip line, the 7th microstrip line, the 8th microstrip line and the 9th microstrip line connected successively is formed; First resonator comprises the tenth microstrip line, the 11 microstrip line, the 12 microstrip line and the 13 microstrip line that connect successively; Second resonator comprises the 14 microstrip line, the 15 microstrip line, the 16 microstrip line and the 17 microstrip line that connect successively; First resonator and the second resonator share a ground short circuit end; Input port in described three ports is positioned at the middle part of the first feed line, and the first output port is drawn from the end of the 9th microstrip line, and the second output port is being arranged in the bandwidth-limited circuit of below and with the first output port in up and down symmetrical.
Further optimization, four resonators are arranged into the structure in specular and are trapped among the outside of the first feed line and the second feed line, first feed line is all bent into rectangle with the second feed line and two ends are not directly connected, and the upper part of the first feed line and the second feed line and lower part are all in specular, the first described microstrip line and the 11 microstrip line are parallel to each other near forming coupling, second microstrip line and the 12 microstrip line are parallel to each other near forming coupling, 3rd microstrip line and the 13 microstrip line are parallel to each other near forming coupling, 6th microstrip line and the 14 microstrip line are parallel to each other near forming coupling, 7th microstrip line and the 15 microstrip line are parallel to each other near forming coupling, 8th microstrip line and the 16 microstrip line are parallel to each other near forming coupling, 9th microstrip line and the 17 microstrip line are parallel to each other near forming coupling, 13 microstrip line and the 14 microstrip line are parallel to each other near forming coupling.
Further optimization, isolation resistance is added in two open ends of the first feed line, enhances the isolation effect of two output ports of circuit.
Further optimization, described loading capacitance and loading variable capacitance diode all have eight, a loading capacitance and one load variable capacitance diode and are connected into one group, and eight groups of circuit after series connection all have one end ground connection, the other end of eight groups of circuit after series connection is correspondingly carried on eight open ends that four resonators and the first feed line, the second feed line formed, namely eight groups of upper and lower symmetry arrangement of circuit after described series connection, the Four composition of the first half not with the tenth microstrip line, 4th microstrip line, the 5th microstrip line is connected with the 9th microstrip line; The two ends of loading variable capacitance diode add voltage source, the structure that the capacitance loading capacitance that the magnitude of voltage changing voltage source just can change loading variable capacitance diode forms with loading variable capacitance diode.
Further optimization, the length of four described resonators is 1/4th of wavelength corresponding to the operating frequency of described bandwidth-limited circuit.
Further optimization, three transmission zeros in this electric adjusting power distributor transmission characteristic are produced with the second feed line and the 3rd feed line source load coupling that formed close to each other respectively by the first feed line.
Further optimization, identical with the path of the second output port (O/P2) to the first output port (O/P1) from input port (I/P), achieve the power-division ratios of 1:1.
Further, frequency divider input and output impedance is 50 ohm, realizes coupling by regulating the coupling between the value of isolation resistance and each microstrip line.
Compared with prior art, the utility model tool has the following advantages and technique effect:
(1) in traditional power divider, band-pass filtering function is integrated with, power division and filter effect can be realized simultaneously, relative to the filter circuit of cascade and power divider, there is less size and less loss, be more conducive to the integra-tion application of radio-frequency (RF) front-end circuit.
(2) the utility model is loaded with variable capacitance diode on the power divider with filter function, achieves operating frequency adjustable.
Accompanying drawing explanation
Fig. 1 is a kind of structure chart with the electric adjusting power distributor of filter function in example.
Fig. 2 is a kind of size marking figure with the electric adjusting power distributor of filter function in example.
Fig. 3 is S
11parameter and S
23the measured result of parameter.
Fig. 4 is S
22parameter and S
33the measured result of parameter.
Fig. 5 is S
21parameter and S
31the measured result of parameter.
Embodiment
Below in conjunction with embodiment and accompanying drawing, enforcement of the present utility model is described in further detail, but execution mode of the present utility model is not limited thereto.
As shown in Figure 1, a kind of electric adjusting power distributor with filter function, comprise upper-layer micro-strip structure, isolation resistance, loading capacitance, loading variable capacitance diode, intermediate medium substrate and underlying metal floor, upper-layer micro-strip structure is attached to the upper surface of intermediate medium substrate, and intermediate medium base lower surface is underlying metal floor; Upper-layer micro-strip structure comprises four resonators, three feed lines and three ports, is arranged into laterally zygomorphic two bandwidth-limited circuits; The bandwidth-limited circuit being arranged in top is made up of the first half 1 of described three feed line first feed lines and the second feed line 4 and described four resonator first resonators 2 and the second resonator 3.
As Fig. 1, the first half 1 of the first feed line is the microstrip line that the first microstrip line 5, second microstrip line 6, the 3rd microstrip line 7 and the 4th microstrip line 8 connected successively is formed; Second feed line 4 is the microstrip line that the 5th microstrip line 9, the 6th microstrip line 10, the 7th microstrip line 11, the 8th microstrip line 12 and the 9th microstrip line 13 connected successively is formed; First resonator 2 comprises the tenth microstrip line the 14, the 11 microstrip line the 15, the 12 microstrip line the 16 and the 13 microstrip line 17 connected successively; Second resonator 3 comprises the 14 microstrip line the 18, the 15 microstrip line the 19, the 16 microstrip line the 20 and the 17 microstrip line 21 connected successively; First resonator 2 and the second resonator 3 share a ground short circuit end 18; Input port I/P in described three ports is positioned at the middle part of the first feed line, first output port O/P1 draws from the end of the 9th microstrip line 13, and the second output port O/P2 is being arranged in the bandwidth-limited circuit of below and with the first output port O/P1 in up and down symmetrical; Described four resonators are bent into two class " several " fonts of upper and lower specular.First feed line is bent into rectangle, the first described microstrip line the 5 and the 11 microstrip line 15 is parallel to each other near forming coupling, second microstrip line the 6 and the 12 microstrip line 16 is parallel to each other near forming coupling, 3rd microstrip line the 7 and the 13 microstrip line 17 is parallel to each other near forming coupling, 6th microstrip line the 10 and the 14 microstrip line 18 is parallel to each other near forming coupling, 7th microstrip line the 11 and the 15 microstrip line 19 is parallel to each other near forming coupling, 8th microstrip line the 12 and the 16 microstrip line 20 is parallel to each other near forming coupling, 9th microstrip line the 13 and the 17 microstrip line 21 is parallel to each other near forming coupling, 13 microstrip line the 17 and the 14 microstrip line 18 is parallel to each other near forming coupling, isolation resistance 26 is added in the two ends of the first feed line, enhances the isolation effect of two output ports of circuit, loading capacitance 22 connect with loading variable capacitance diode 24 after ground connection 25, add voltage source 23 loading the two ends of variable capacitance diode 24, the magnitude of voltage changing voltage source 23 just can change the capacitance of loading variable capacitance diode, the electric adjusting power distributor of described a kind of filter function has eight loading capacitances and the structure loading variable capacitance diode and form, upper and lower symmetry arrangement, four of the first half are connected with the 9th microstrip line 13 with the tenth microstrip line the 14, four microstrip line the 8, five microstrip line 9 respectively.
The length of four described resonators is 1/4th of wavelength corresponding to the operating frequency of described bandwidth-limited circuit; First feed line respectively with the second feed line and the 3rd feed line formation source close to each other load coupling, three transmission zeros in the transmission characteristic of the electric adjusting power distributor of described a kind of filter function; Input and output impedance is 50 ohm, by regulating the coupling between the value of isolation resistance (26) and each microstrip line.
Embodiment
As shown in Figure 2, as an example, have the design of the electric adjusting power distributor of filter function, physical circuit size Selection is as follows:
w 1=2.33mm,
w 2=0.5mm,
w 3=1.4mm,
w 4=0.5mm,
w 5=1.3mm,
l 1=2mm,
l 2=9.7mm,
l 3=12.9mm,
l 4=10.1mm,
l 5=3mm,
l 6=8.5mm,
l 7=1.2mm,
l 8=1.2mm,
l 9=6.7mm,
l 10=7mm,
l 11=9.4mm,
g 1=0.2mm,
g 2=0.3mm,
g 3=0.15mm,
g 4=1.2mm,
g 5=0.3mm,
d=0.8mm,
r=150 Ω,
c 1=2pF; That select variable capacitance diode in the design is the 1sv277 of Toshiba.Overall dimensions is 34mm × 23.6mm.
Be illustrated in figure 3 S
11and S
23measured result, known, return loss is greater than 20dB, isolation be better than 18dB.
Be illustrated in figure 4 S
22and S
33measured result, be under any circumstance all better than 15dB, achieve good coupling.
Be illustrated in figure 5 S
21and S
31measured result, under any circumstance, Out-of-band rejection is all better than 28dB, suppress level high; Produce transmission zero near pass-band synchronously to change along with source load coupling, realize high selectivity; In addition, circuit is adjustable in centre frequency (0.83GHz-1.13GHz) scope, and adjustable extent is 30.6%; Meanwhile, when after frequency shift, the property indices of circuit keeps good, demonstrates the correctness of the utility model design theory well.
To sum up, the utility model provides a kind of electric adjusting power distributor with filter function, has volume little, good wave filtering effect, the excellent properties of regulable center frequency, is applicable to being applied in the radio-frequency front-end of wireless communication system.
Embodiment described above is an embodiment of having taught in the utility model, not in order to limit the utility model.Based on embodiment of the present utility model; those of ordinary skill in the art, under the prerequisite not making creative work, based on any amendment that the utility model makes, are equal to and replace; improve other embodiments obtained, all belong to the protection range of the utility model embodiment.
Claims (8)
1. one kind has the electric adjusting power distributor of filter function, comprise upper-layer micro-strip structure, isolation resistance (26), loading capacitance (22), load variable capacitance diode (24), intermediate medium substrate and underlying metal floor, upper-layer micro-strip structure is attached to the upper surface of intermediate medium substrate, and intermediate medium base lower surface is underlying metal floor; It is characterized in that: described upper-layer micro-strip structure comprises four resonators, three feed lines and three ports, and be arranged into laterally zygomorphic two bandwidth-limited circuits; The bandwidth-limited circuit being arranged in top is made up of with the second resonator (3) with the second feed line (4) and described four resonator first resonators (2) the first half (1) of described three feed line first feed lines; Wherein the first half (1) of the first feed line is the microstrip line that the first microstrip line (5), the second microstrip line (6), the 3rd microstrip line (7) and the 4th microstrip line (8) connected successively is formed; Second feed line (4) is the microstrip line that the 5th microstrip line (9), the 6th microstrip line (10), the 7th microstrip line (11), the 8th microstrip line (12) and the 9th microstrip line (13) connected successively is formed; First resonator (2) comprises the tenth microstrip line (14), the 11 microstrip line (15), the 12 microstrip line (16) and the 13 microstrip line (17) that connect successively; Second resonator (3) comprises the 14 microstrip line (18), the 15 microstrip line (19), the 16 microstrip line (20) and the 17 microstrip line (21) that connect successively; First resonator (2) and the second resonator (3) share a ground short circuit end; Input port (I/P) in described three ports is positioned at the middle part of the first feed line, first output port (O/P1) is drawn from the end of the 9th microstrip line (13), and the second output port (O/P2) is being arranged in the bandwidth-limited circuit of below and with the first output port (O/P1) in up and down symmetrical.
2. a kind of electric adjusting power distributor with filter function according to claim 1, is characterized in that four resonators are arranged into the structure in specular and are trapped among the outside of the first feed line and the second feed line, first feed line is all bent into rectangle with the second feed line and two ends are not directly connected, and the upper part of the first feed line and the second feed line and lower part are all in specular, described the first microstrip line (5) and the 11 microstrip line (15) are parallel to each other near forming coupling, second microstrip line (6) and the 12 microstrip line (16) are parallel to each other near forming coupling, 3rd microstrip line (7) and the 13 microstrip line (17) are parallel to each other near forming coupling, 6th microstrip line (10) and the 14 microstrip line (18) are parallel to each other near forming coupling, 7th microstrip line (11) and the 15 microstrip line (19) are parallel to each other near forming coupling, 8th microstrip line (12) and the 16 microstrip line (20) are parallel to each other near forming coupling, 9th microstrip line (13) and the 17 microstrip line (21) are parallel to each other near forming coupling, 13 microstrip line (17) and the 14 microstrip line (18) are parallel to each other near forming coupling.
3. a kind of electric adjusting power distributor with filter function according to claim 1, is characterized in that isolation resistance (26) is added in two open ends of the first feed line.
4. a kind of electric adjusting power distributor with filter function according to claim 1, it is characterized in that described loading capacitance and load variable capacitance diode all having eight, loading capacitance (22) loads variable capacitance diode (24) be connected into one group with one, and eight groups of circuit after series connection all have one end ground connection (25), the other end of eight groups of circuit after series connection is correspondingly carried in four resonators and the first feed line, on eight open ends that second feed line is formed, namely eight groups of upper and lower symmetry arrangement of circuit after described series connection, the Four composition of the first half not with the tenth microstrip line (14), 4th microstrip line (8), 5th microstrip line (9) is connected with the 9th microstrip line (13), the two ends of loading variable capacitance diode (24) add voltage source (23), the structure that the capacitance loading capacitance that the magnitude of voltage changing voltage source (23) just can change loading variable capacitance diode forms with loading variable capacitance diode.
5. a kind of electric adjusting power distributor with filter function according to claim 1, is characterized in that the length of four described resonators is 1/4th of wavelength corresponding to the operating frequency of described bandwidth-limited circuit.
6. a kind of electric adjusting power distributor with filter function according to claim 1, is characterized in that three transmission zeros in this electric adjusting power distributor transmission characteristic are produced with the second feed line and the 3rd feed line source load coupling that formed close to each other respectively by the first feed line.
7. a kind of electric adjusting power distributor with filter function according to claim 2, it is characterized in that from input port (I/P) identical with the path of the second output port (O/P2) to the first output port (O/P1), achieve the power-division ratios of 1:1.
8. a kind of electric adjusting power distributor with filter function according to any one of claim 1 ~ 7, is characterized in that frequency divider input and output impedance is 50 ohm, realizes coupling by regulating the coupling between the value of isolation resistance (26) and each microstrip line.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201420740449.7U CN204205018U (en) | 2014-11-29 | 2014-11-29 | A kind of electric adjusting power distributor with filter function |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201420740449.7U CN204205018U (en) | 2014-11-29 | 2014-11-29 | A kind of electric adjusting power distributor with filter function |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104466335A (en) * | 2014-11-29 | 2015-03-25 | 华南理工大学 | Electric adjusting power divider with filter function |
| CN104701591A (en) * | 2015-03-19 | 2015-06-10 | 华南理工大学 | Electrically adjusting common mode rejection filter based on selective frequency coupling |
| CN109473756A (en) * | 2018-11-16 | 2019-03-15 | 西安电子科技大学 | A kind of complete restructural difference filter |
-
2014
- 2014-11-29 CN CN201420740449.7U patent/CN204205018U/en not_active Withdrawn - After Issue
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104466335A (en) * | 2014-11-29 | 2015-03-25 | 华南理工大学 | Electric adjusting power divider with filter function |
| CN104466335B (en) * | 2014-11-29 | 2017-06-06 | 华南理工大学 | A kind of electric adjusting power distributor with filter function |
| CN104701591A (en) * | 2015-03-19 | 2015-06-10 | 华南理工大学 | Electrically adjusting common mode rejection filter based on selective frequency coupling |
| CN104701591B (en) * | 2015-03-19 | 2017-04-19 | 华南理工大学 | Electrically adjusting common mode rejection filter based on selective frequency coupling |
| CN109473756A (en) * | 2018-11-16 | 2019-03-15 | 西安电子科技大学 | A kind of complete restructural difference filter |
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| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
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| AV01 | Patent right actively abandoned |
Granted publication date: 20150311 Effective date of abandoning: 20170606 |