CN118156760A - Power divider, phase shifter and base station antenna - Google Patents
Power divider, phase shifter and base station antenna Download PDFInfo
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- CN118156760A CN118156760A CN202410434865.2A CN202410434865A CN118156760A CN 118156760 A CN118156760 A CN 118156760A CN 202410434865 A CN202410434865 A CN 202410434865A CN 118156760 A CN118156760 A CN 118156760A
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- transmission line
- power divider
- output ports
- isolation resistor
- phase shifter
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- 230000005540 biological transmission Effects 0.000 claims abstract description 81
- 238000002955 isolation Methods 0.000 claims abstract description 58
- 238000001914 filtration Methods 0.000 abstract description 5
- 230000000694 effects Effects 0.000 description 7
- 238000010586 diagram Methods 0.000 description 4
- 238000000034 method Methods 0.000 description 4
- 238000004512 die casting Methods 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 238000004458 analytical method Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 230000005855 radiation Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- 230000001629 suppression Effects 0.000 description 2
- 238000003491 array Methods 0.000 description 1
- 238000004891 communication Methods 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 230000010354 integration Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
- 230000003071 parasitic effect Effects 0.000 description 1
- 230000010363 phase shift Effects 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 230000008054 signal transmission Effects 0.000 description 1
- 230000009466 transformation Effects 0.000 description 1
Classifications
-
- 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
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q1/00—Details of, or arrangements associated with, antennas
- H01Q1/12—Supports; Mounting means
- H01Q1/22—Supports; Mounting means by structural association with other equipment or articles
- H01Q1/24—Supports; Mounting means by structural association with other equipment or articles with receiving set
- H01Q1/241—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM
- H01Q1/246—Supports; Mounting means by structural association with other equipment or articles with receiving set used in mobile communications, e.g. GSM specially adapted for base stations
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q3/00—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system
- H01Q3/26—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture
- H01Q3/30—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array
- H01Q3/34—Arrangements for changing or varying the orientation or the shape of the directional pattern of the waves radiated from an antenna or antenna system varying the relative phase or relative amplitude of energisation between two or more active radiating elements; varying the distribution of energy across a radiating aperture varying the relative phase between the radiating elements of an array by electrical means
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- Engineering & Computer Science (AREA)
- Computer Networks & Wireless Communication (AREA)
- Transmitters (AREA)
Abstract
The application provides a power divider, a phase shifter and a base station antenna. The power divider includes an input port, a plurality of output ports, at least one isolation resistor, and a plurality of transmission lines. The input port is used for accessing an input signal. And a preset interval is arranged between the adjacent output ports. An isolation resistor is arranged between two adjacent output ports. Each transmission line is arranged between the adjacent input port and the isolation resistor; the length of each transmission line is 4 lambda/9-5 lambda/9; and lambda is the wavelength of the central frequency point of the input signal. The application can flexibly set the positions of a plurality of output ports and isolation resistors by arranging the transmission line with a certain length, so that the circuit design is flexible, and the adjacent output ports can have larger preset interval, thereby improving the isolation degree of the adjacent output ports. By setting the length of the transmission line to be 4 lambda/9-5 lambda/9, the input signals of corresponding frequency points can be inhibited, and the filtering function is realized.
Description
Technical Field
The present application relates to the field of power splitters, and in particular, to a power splitter, a phase shifter, and a base station antenna.
Background
With the increasing shortage of base station resources, base station antennas are rapidly developing toward multi-frequency and multi-port directions. Due to the limitation of the iron tower to the windward area of the base station antenna, the multi-frequency multi-port base station antenna with higher integration level is more densely distributed, so that the isolation of the radiating arrays between different frequency bands is deteriorated, and the communication quality is affected. The situation of poor separation degree between different frequency bands mainly occurs in a multi-frequency multi-port base station antenna with a 2-frequency multiplication relation. For example, in a base station antenna including the 820-960MHz and 1710-2170MHz bands, since the low frequency element has a parasitic passband around its 2 times the center frequency, a part of the high frequency signal may flow through the low frequency circuit, causing signal interference.
At present, two methods for optimizing the isolation degree of different frequencies are mainly adopted, one method is to make a band-stop filter structure on the radiation surface of a low-frequency oscillator to inhibit high-frequency signals, the method is generally applicable to oscillators in a PCB (Printed Circuit Board ) form, but the structural reliability of the PCB oscillator is inferior to that of a die-casting oscillator, and most base station antennas of mainstream factories in industry use the die-casting oscillator; the other is to add a filter in the feed network to suppress the pilot frequency signal, and the method is applicable to both die-casting vibrators and PCB vibrators, but the newly introduced filter brings extra circuit loss and reduces the radiation efficiency of the base station antenna.
Disclosure of Invention
In order to solve the problems in the prior art, the application provides a power divider, a phase shifter and a base station antenna, so as to improve the isolation performance of the power divider and realize the filtering effect of the power divider.
The application provides a power divider, which comprises:
an input port for accessing an input signal;
The plurality of output ports are provided with preset intervals between adjacent output ports;
At least one isolation resistor, wherein an isolation resistor is arranged between two adjacent output ports;
A plurality of transmission lines, each of which is arranged between an adjacent input port and an isolation resistor; the length of each transmission line is 4 lambda/9-5 lambda/9; and lambda is the wavelength of the central frequency point of the input signal.
In an embodiment, the power divider further comprises an impedance transformer; the impedance transformer is disposed between the input port and a plurality of the output ports.
In one embodiment, the impedance transformer has a length of λ/8 to λ/4.
In one embodiment, each of the transmission lines has a length λ/2.
In one embodiment, the impedance of the transmission line is determined based on the power ratio of two output ports adjacent to the transmission line and the characteristic impedance; the impedance of the isolation resistor is determined according to the power ratio of two output ports adjacent to the isolation resistor and the characteristic impedance.
In one embodiment, the power divider comprises a first output port, a second output port, a first isolation resistor, a first transmission line and a second transmission line;
A first end of the first transmission line is electrically connected with the first output port, and a second end of the first transmission line is electrically connected with a first end of the first isolation resistor; the first end of the second transmission line is electrically connected with the second output port, and the second end of the second transmission line is electrically connected with the second end of the first isolation resistor.
The application also provides a phase shifter, which comprises the power divider.
In one embodiment, the number of the power splitters is a plurality.
The application also provides a base station antenna, which comprises the phase shifter.
In an embodiment, the base station antenna further comprises a plurality of elements.
The application can flexibly set the positions of a plurality of output ports and isolation resistors by arranging the transmission line with a certain length, so that the circuit design is flexible, and the adjacent output ports can have larger preset interval, thereby improving the isolation degree of the adjacent output ports. By setting the length of the transmission line to be 4 lambda/9-5 lambda/9, the input signals of corresponding frequency points can be inhibited, and the filtering function is realized.
Drawings
FIG. 1 is a block diagram of an embodiment of a power divider of the present application.
Fig. 2 is a block diagram of another embodiment of a power divider assembly according to the present application.
Fig. 3 is an S-parameter graph of an embodiment of the power divider of the present application.
Fig. 4 is a block diagram of an embodiment of a phase shifter according to the present application.
FIG. 5 is a graph showing the reflection coefficient of an embodiment of the phase shifter of the present application.
Fig. 6 is a block diagram of a base station antenna according to an embodiment of the present application.
Description of the main reference signs
Input port 110 of power divider 100
Output port 120 isolation resistor R
Impedance transformer 140 for transmission line 130
First output port 121 and second output port 122
First isolation resistor R1 first transmission line 131
Second transmission line 132 third output port 123
Second isolation resistor R2 third transmission line 133
Fourth transmission line 134 phase shifter 10
Base station antenna 1 vibrator 20
The application will be further described in the following detailed description in conjunction with the above-described figures.
Detailed Description
The following description will make reference to the accompanying drawings to more fully describe the application. Exemplary embodiments of the present application are illustrated in the accompanying drawings. This application may, however, be embodied in many different forms and should not be construed as limited to the exemplary embodiments set forth herein. These exemplary embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the application to those skilled in the art. Like reference numerals designate identical or similar components.
At present, a wilkinson power divider is used in a phase shifter to realize multi-port power distribution. However, the conventional wilkinson power divider does not have a filter characteristic, and the ends of the impedance transformers at the two power dividing ends are close to each other, and the isolation resistors are disposed at the ends of the impedance transformers. This circuit layout structure results in that the circuit layout of the phase shifter cannot achieve a compact effect when it is applied to the phase shifter, and additionally increases the size of the phase shifter.
Referring to fig. 1 and 2, the present application proposes a power divider 100, the power divider 100 including an input port 110, a plurality of output ports 120, at least one isolation resistor R, and a plurality of transmission lines 130. The input port 110 is used to access an input signal. The plurality of output ports 120 are adjacent to the output ports 120 with a predetermined interval therebetween. An isolation resistor R is disposed between two adjacent output ports 120. Each transmission line 130 is disposed between the adjacent input port 110 and the isolation resistor R; the length of each transmission line 130 is 4 lambda/9-5 lambda/9; and lambda is the wavelength of the central frequency point of the input signal.
In this embodiment, the power divider 100 may be disposed on a dielectric circuit board. The transmission line 130 may be implemented as a microstrip line. By connecting the output ports 120 with the isolation resistors R through the transmission line 130 having a certain length, the positions of the adjacent two output ports 120 and the isolation resistors R can be flexibly set, so that the circuit design is more flexible. The preset interval between the adjacent output ports 120 may be set according to practical applications, for example, according to the width or length of the circuit board. Since the transmission line 130 has a certain length, the preset interval between the adjacent output ports 120 can also be increased along with the increase of the length of the transmission line 130 under the condition of meeting the size requirement, so as to improve the isolation between the output ports 120.
The length of the transmission line 130 is set to be 4λ/9-5λ/9, which can play a role in suppressing f/2±10% f/2 frequency bands, where f is the center frequency point of the input signal. For example, the length of the transmission line 130 is set to λ/2, and λ/4 for the f/2 frequency point. As can be seen from the odd-mode analysis, the f/2 input signal has an impedance transformation effect through the lambda/4 transmission line 130, and is represented by Z2/50 (Z is the characteristic impedance), which is considered to be still high-impedance, so that the reflection coefficient is about 1. As can be seen from even mode analysis, the f/2 input signal is transformed to a short circuit via the lambda/4 transmission line 130, where the reflection coefficient is about-1. The gain of the f/2 input signal should be shown here as 1+ (-1)/2, i.e. 0, when analyzed in the odd and even modes of the sum. I.e., lambda/2 transmission line 130 exhibits a suppressing effect on the input signal of f/2. Fig. 3 shows S parameters of the power divider 100 at a center frequency of 1940 MHz. It can be seen that the isolation between the two output ports 120 is greater than 18dB, while the power divider 100 has a suppression effect on the vicinity of the 970MHz frequency point. In addition, the length of the transmission line 130 may be set to be any value between 4λ/9, 5λ/9, or 4λ/9-5λ/9 according to actual requirements, so as to inhibit corresponding frequency points and achieve a filtering effect.
In one embodiment, the power divider 100 further includes an impedance transformer 140; the impedance transformer 140 is disposed between the input port 110 and the plurality of output ports 120.
In this embodiment, the impedance transformer 140 may be used to adjust the impedance match between the input port 110 and the output port 120. The length of the impedance transformer 140 may be set according to practical requirements, for example, to λ/8 to λ/4. The width of the impedance transformer 140 can also be adjusted according to the actual impedance requirement to achieve impedance matching between the input port 110 and the output port 120.
In one embodiment, the impedance of the transmission line 130 is determined based on the power ratio and the characteristic impedance of two output ports 120 adjacent to the transmission line 130; the impedance of the isolation resistor R is determined based on the power ratio of the two output ports 120 adjacent to the isolation resistor R and the characteristic impedance.
For example, the two adjacent output ports 120 are the mth output port 120 and the nth output port 120, respectively. The impedance of the transmission line 130 is (kmn+1/Kmn) Z, kmn 2=pm/Pn. Where Pm is the power of the mth output port 120, pn is the power of the nth output port 120, and Z is the characteristic impedance between the mth output port 120 and the nth output port 120. Similarly, the impedance of the isolation resistor R provided between the mth output port 120 and the nth output port 120 is the same as the impedance of the transmission line 130 provided between the mth output port 120 and the nth output port 120. In this way, impedance matching between the mth output port 120 and the nth output port 120 can be achieved. Meanwhile, the isolation resistor R has higher impedance, so that signals between two adjacent output ports 120 can be isolated, signal interference is avoided, and isolation between the two adjacent output ports 120 is improved.
In one embodiment, the power divider 100 includes a first output port 121, a second output port 122, a first isolation resistor R1, a first transmission line 131, and a second transmission line 132. A first end of the first transmission line 131 is electrically connected to the first output port 121, and a second end of the first transmission line 131 is electrically connected to a first end of the first isolation resistor R1; a first end of the second transmission line 132 is electrically connected to the second output port 122, and a second end of the second transmission line 132 is electrically connected to a second end of the first isolation resistor R1.
In the present embodiment, the impedance of the first transmission line 131 is (k12+1/k12) ×z, k12++2=p1/p2. The impedance of the second transmission line 132 and the impedance of the first isolation resistor R1 coincide with the impedance of the first transmission line 131.
Referring to fig. 2, in an embodiment, the power divider 100 includes a first output port 121, a second output port 122, a third output port 123, a first isolation resistor R1, a second isolation resistor R2, a first transmission line 131, a second transmission line 132, a third transmission line 133, and a fourth transmission line 134. A first end of the first transmission line 131 is electrically connected to the first output port 121, and a second end of the first transmission line 131 is electrically connected to a first end of the first isolation resistor R1; a first end of the second transmission line 132 is electrically connected to the second output port 122, and a second end of the second transmission line 132 is electrically connected to a second end of the first isolation resistor R1. A first end of the third transmission line 133 is electrically connected to the second output port 122, and a second end of the third transmission line 133 is electrically connected to a first end of the second isolation resistor R2; a first end of the fourth transmission line 134 is electrically connected to the third output port 123, and a second end of the fourth transmission line 134 is electrically connected to a second end of the second isolation resistor R2.
In the present embodiment, the impedance of the first transmission line 131 is (k12+1/k12) ×z, k12++2=p1/p2. The impedance of the second transmission line 132 and the impedance of the first isolation resistor R1 coincide with the impedance of the first transmission line 131. The impedance of the third transmission line 133 is (k23+1/k23) Z, k23++2=p2/P3. The impedance of the fourth transmission line 134 and the impedance of the second isolation resistor R2 coincide with the impedance of the third transmission line 133.
The application can flexibly set the positions of a plurality of output ports 120 and isolation resistors R by arranging the transmission line 130 with a certain length, so that the circuit design is flexible, and the adjacent output ports 120 can have larger preset interval, thereby improving the isolation of the adjacent output ports 120. By setting the length of the transmission line 130 to 4λ/9 to 5λ/9, the input signal of the corresponding frequency point can be suppressed, and the filtering function can be realized.
Referring to fig. 4, the present application also proposes a phase shifter 10, where the phase shifter 10 includes the aforementioned power divider 100.
The detailed structure of the power divider 100 can refer to the above embodiments, and will not be described herein again; it can be understood that, since the aforementioned power divider 100 is used in the phase shifter 10 of the present invention, the embodiments of the phase shifter 10 of the present invention include all the technical solutions of all the embodiments of the aforementioned power divider 100, and the achieved technical effects are identical, and are not repeated herein.
Fig. 5 shows a reflection coefficient curve of the input port 110 of the phase shifter 10 according to the present application, which can effectively inhibit 820-960MHz signal transmission and reduce signal interference between different frequency bands while realizing good transmission of 1700-2100MHz electromagnetic wave by the phase shifter 10.
In one embodiment, the number of the power splitters 100 is plural.
In this embodiment, the power divider 100 may be disposed at the end of the phase shifter 10. Multiple power splitters 100 may be cascaded. For example, the phase shifter 10 includes a first power divider 100, a second power divider 100, and a third power divider 100, each power divider 100 having one input port 110 and two output ports 120. The input end of the first power divider 100 is used for accessing an input signal, and two output ends of the first power divider 100 are respectively and electrically connected with the input end of the second power divider 100 and the input end of the third power divider 100. In this manner, power distribution to the plurality of output ports 120 is achieved through multi-stage power splitting.
Referring to fig. 6, the present application also proposes a base station antenna 1, said base station antenna 1 comprising the phase shifter 10 described above.
The detailed structure of the phase shifter 10 can be referred to the above embodiments, and will not be described herein; it can be understood that, since the above-mentioned phase shifter 10 is used in the base station antenna 1 of the present invention, the embodiments of the base station antenna 1 of the present invention include all the technical solutions of all the embodiments of the above-mentioned phase shifter 10, and the achieved technical effects are also identical, and are not described herein again.
In an embodiment, the base station antenna 1 further comprises a plurality of elements 20.
In this embodiment, the number of vibrator 20 components corresponds to the number of output ports 120 of the phase shifter 10. The input signal is subjected to power division and phase shift by the phase shifter 10 and then is output to the vibrator 20 assembly to excite the vibrator 20 assembly to work. Because the plurality of output ports 120 of the power divider 100 of the phase shifter 10 have higher isolation, mutual coupling between adjacent units of the oscillator 20 can be effectively reduced, upper sidelobe suppression on a vertical plane of the base station antenna 1 is optimized, and the directivity of the base station antenna 1 is improved. Meanwhile, the isolation between different frequencies is optimized without introducing a filter.
Hereinabove, the specific embodiments of the present application are described with reference to the accompanying drawings. Those skilled in the art will appreciate that various modifications and substitutions can be made to the application in its specific embodiments without departing from the spirit and scope of the application. Such modifications and substitutions are intended to be included within the scope of the present application.
Claims (10)
1. A power divider, the power divider comprising:
an input port for accessing an input signal;
The plurality of output ports are provided with preset intervals between adjacent output ports;
At least one isolation resistor, wherein an isolation resistor is arranged between two adjacent output ports;
A plurality of transmission lines, each of which is arranged between an adjacent input port and an isolation resistor; the length of each transmission line is 4 lambda/9-5 lambda/9; and lambda is the wavelength of the central frequency point of the input signal.
2. The power divider of claim 1, further comprising an impedance transformer; the impedance transformer is disposed between the input port and a plurality of the output ports.
3. The power divider of claim 2, wherein the impedance transformer has a length of λ/8 to λ/4.
4. The power divider of claim 1, wherein each of said transmission lines has a length λ/2.
5. The power divider of claim 1, wherein the impedance of the transmission line is determined based on a power ratio of two output ports adjacent to the transmission line and a characteristic impedance; the impedance of the isolation resistor is determined according to the power ratio of two output ports adjacent to the isolation resistor and the characteristic impedance.
6. The power divider of claim 1, wherein the power divider comprises a first output port, a second output port, a first isolation resistor, a first transmission line, and a second transmission line;
A first end of the first transmission line is electrically connected with the first output port, and a second end of the first transmission line is electrically connected with a first end of the first isolation resistor; the first end of the second transmission line is electrically connected with the second output port, and the second end of the second transmission line is electrically connected with the second end of the first isolation resistor.
7. A phase shifter, characterized in that the phase shifter comprises a power divider according to any one of claims 1 to 6.
8. The phase shifter of claim 7, wherein the number of power splitters is a plurality.
9. A base station antenna, characterized in that it comprises a phase shifter according to claim 7 or 8.
10. The base station antenna of claim 9, wherein the base station antenna further comprises a plurality of elements.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410434865.2A CN118156760A (en) | 2024-04-10 | 2024-04-10 | Power divider, phase shifter and base station antenna |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202410434865.2A CN118156760A (en) | 2024-04-10 | 2024-04-10 | Power divider, phase shifter and base station antenna |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN118156760A true CN118156760A (en) | 2024-06-07 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202410434865.2A Pending CN118156760A (en) | 2024-04-10 | 2024-04-10 | Power divider, phase shifter and base station antenna |
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| Country | Link |
|---|---|
| CN (1) | CN118156760A (en) |
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2024
- 2024-04-10 CN CN202410434865.2A patent/CN118156760A/en active Pending
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