CN114978251A

CN114978251A - Phase shifter and base station test system

Info

Publication number: CN114978251A
Application number: CN202110201729.5A
Authority: CN
Inventors: 李敬华; 王世华; 屈红亮; 高军
Original assignee: Datang Mobile Communications Equipment Co Ltd
Current assignee: Datang Mobile Communications Equipment Co Ltd
Priority date: 2021-02-23
Filing date: 2021-02-23
Publication date: 2022-08-30
Anticipated expiration: 2041-02-23
Also published as: CN114978251B

Abstract

The embodiment of the invention provides a phase shifter and a base station test system, and relates to the technical field of communication. The phase shifter includes: the phase-shifting circuit comprises M signal input circuits, N signal output circuits and a phase-shifting network circuit arranged between the signal input circuits and the signal output circuits; m and N are integer multiples of 2; the phase-shifting network circuit comprises M power dividers, N combiners and M multiplied by N strip lines between the M power dividers and the N combiners, wherein the length of each strip line included in the phase-shifting network circuit is determined based on a plurality of different beam forming angles included by test requirements, and the strip lines correspond to the beam forming angles one to one; each signal input circuit is respectively connected with the input of one power divider; the output of each power divider is respectively connected with the input of one combiner; the output of each combiner is respectively connected with a signal output circuit. The structure of the phase shifter can be simplified on the basis of saving cost.

Description

Phase shifter and base station test system

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a phase shifter and a base station test system.

Background

Mobile communication systems have been developed to 5 th generation, 5G communication systems. The 5G communication system uses an array antenna to implement beamforming and Multiple Input Multiple Output (MIMO) modes. The parallel sending of the multi-channel data streams can be realized through a large-scale MIMO mode, the spatial multiplexing gain is obtained, and the transmission effectiveness is improved. And the combination of a plurality of sub-channel signals can be realized, the space diversity gain is obtained, and the transmission reliability is improved.

In order to verify the performance of the 5G communication system adopting beamforming and MIMO mode, the MIMO base station system may be tested in a laboratory by adopting a conduction test method. The transmission path between a base station and a terminal in the MIMO base station system is simulated through a phase shifter, and the base station communicates with the terminal through the phase shifter to further obtain test data.

At present, the transmission path of the MIMO base station system can be simulated through an active phase shifter, but the active phase shifter comprises an attenuator, a phase shifting device and the like, and has a complex structure and high required cost.

Disclosure of Invention

Embodiments of the present invention provide a phase shifter and a base station testing system, so as to simplify the structure of the phase shifter on the basis of saving cost. The specific technical scheme is as follows:

in a first aspect, an embodiment of the present application provides a phase shifter, including: the phase-shifting circuit comprises M signal input circuits, N signal output circuits and a phase-shifting network circuit arranged between the signal input circuits and the signal output circuits; m and N are integer multiples of 2;

the phase-shifting network circuit comprises M power dividers, N combiners and M multiplied by N strip lines between the M power dividers and the N combiners, wherein the length of each strip line included in the phase-shifting network circuit is determined based on a plurality of different beam forming angles included by test requirements, and the strip lines are in one-to-one correspondence with the beam forming angles; the power divider is a 1-to-N power divider, and the combiner is an M-to-1 combiner;

each signal input circuit is respectively connected with the input of one power divider; the output of each power divider is respectively connected with the input of one combiner; the output of each combiner is respectively connected with a signal output circuit.

In one possible implementation manner, the M signal input circuits, the N signal output circuits, the M power dividers, and the N combiners are all located on a first metal wiring layer of a printed circuit board PCB;

the strip line is located on the first metal wiring layer and the second metal wiring layer of the PCB, a through hole is formed in the first metal wiring layer, and the through hole is used for communicating the same strip line on the first metal wiring layer and the second metal wiring layer.

In a possible implementation manner, the M power splitters are sequentially arranged on one side of the first metal wiring layer, the N combiners are sequentially arranged on the other side of the first metal wiring layer, and the M power splitters are opposite to the N combiners.

In a possible implementation manner, the via holes on the side close to the power dividers and the via holes on the side close to the combiners on the first metal wiring layer are symmetrically arranged with respect to a first central line, and the first central line is a central line between a column where the M power dividers are located and a column where the N combiners are located on the first metal wiring layer.

In a possible implementation manner, the phase shift network circuit includes M/2 power dividers sequentially arranged on one side of the first metal wiring layer, and the other M/2 power dividers sequentially arranged on the other side of the first metal wiring layer;

the N combiners are sequentially arranged between the two rows of power dividers, half input ports of each combiner face to the power divider on one side, and the other half input ports face to the power dividers on the other side.

In a possible implementation manner, the N combiners are sequentially arranged on the second central lines of the two columns of power dividers; or, the N combiners are staggered with respect to the second center line.

In one possible implementation manner, the vias on both sides of each combiner on the first metal wiring layer are symmetrically arranged with respect to the second central line.

In a second aspect, an embodiment of the present application provides a phase shifter, including: the phase-shifting network circuit comprises M first duplexers, N second duplexers, an uplink phase-shifting network circuit and a downlink phase-shifting network circuit, wherein the uplink phase-shifting network circuit and the downlink phase-shifting network circuit are arranged between the M first duplexers and the N second duplexers, and both M and N are integer multiples of 2;

the uplink phase-shifting network circuit comprises M combiners, N power dividers and M multiplied by N strip lines between the M combiners and the N power dividers, wherein the length of each strip line included by the uplink phase-shifting network circuit is determined based on a plurality of different beam forming angles included by test requirements, and the strip lines included by the uplink phase-shifting network circuit correspond to the beam forming angles one to one; the combiner included in the uplink phase-shifting network circuit is an N-in-1 combiner, and the power divider included in the uplink phase-shifting network circuit is a 1-divider-M power divider;

the downlink phase shift network circuit comprises M power dividers, N combiners and M multiplied by N strip lines between the M power dividers and the N combiners, wherein the length of each strip line included by the downlink phase shift network circuit is determined based on a plurality of different beam forming angles included by test requirements, and the strip lines included by the downlink phase shift network are in one-to-one correspondence with the beam forming angles; the power divider included in the downlink phase-shifting network circuit is a 1-to-N power divider, and the combiner included in the downlink phase-shifting network circuit is an M-to-1 combiner;

each first duplexer is connected to the input of one power divider in the uplink phase-shifting network circuit, the output of each power divider in the uplink phase-shifting network circuit is connected to the input of one combiner, and the output of each combiner is connected to one second duplexer;

each second duplexer is respectively connected to the input of one power divider in the downlink phase-shifting network circuit, the output of each power divider in the downlink phase-shifting network circuit is respectively connected to the input of one combiner, and the output of each combiner is respectively connected to one first duplexer.

In a possible implementation manner, the M first duplexers, the N second duplexers, the M combiners and the N power dividers included in the uplink phase-shift network circuit, and the M power dividers and the N combiners included in the downlink phase-shift network circuit are all located in a first metal wiring layer of a printed circuit board PCB;

In a possible implementation manner, in the uplink phase shift network circuit, the M combiners are sequentially arranged on one side of the first metal wiring layer, and the N power dividers are sequentially arranged on the other side of the first metal wiring layer; or, M/2 combiners are sequentially arranged on one side of the first metal wiring layer, the other M/2 combiners are sequentially arranged on the other side of the first metal wiring layer, and the N power dividers are sequentially arranged on the central lines of the two columns of combiners or are staggered relative to the central lines of the two columns of combiners;

in the downlink phase shift network circuit, the M power dividers are sequentially arranged on one side of the first metal wiring layer, and the N combiners are sequentially arranged on the other side of the first metal wiring layer; or, M/2 power dividers are sequentially arranged on one side of the first metal wiring layer, the other M/2 power dividers are sequentially arranged on the other side of the first metal wiring layer, and the N combiners are sequentially arranged on the central lines of the two rows of power dividers, or are staggered relative to the central lines of the two rows of power dividers.

In a third aspect, an embodiment of the present application provides a base station test system, where the system includes a test base station, a plurality of test terminals, and the phase shifter according to the second aspect;

the M radio frequency channels of the test base station are connected with the M first duplexers of the phase shifter one by one, and the radio frequency channels of the plurality of test terminals are connected with the N second duplexers of the phase shifter one by one.

By adopting the technical scheme, the phase shifter comprises M signal input circuits, N signal output circuits and a phase shifting network circuit, wherein the phase shifting network circuit comprises M power dividers, N combiners and M multiplied by N strip lines between the M power dividers and the N combiners. It can be seen that the phase shifter in the embodiment of the present application includes a simple circuit, and the length of the strip line is set based on the test requirement, so that a plurality of beam forming angles required by the test can be realized, no complex structural design is required, no devices such as an attenuator are required, the structure is simple, and the cost is low.

Of course, not all of the advantages described above need to be achieved at the same time in the practice of any one product or method of the invention.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are only some embodiments of the present invention, and it is obvious for those skilled in the art that other embodiments can be obtained by using the drawings without creative efforts.

Fig. 1 is a schematic diagram of a beam forming principle of an array antenna according to an embodiment of the present application;

fig. 2 is a schematic diagram of a MIMO mode according to an embodiment of the present application;

fig. 3 is a schematic structural diagram of a phase shifter according to an embodiment of the present disclosure;

FIG. 4 is an exemplary schematic diagram of a phase shifting network circuit provided in an embodiment of the present application;

FIG. 5 is a schematic diagram of a phase shifting network circuit according to an embodiment of the present disclosure;

FIG. 6 is a schematic diagram of another phase shifting network circuit according to an embodiment of the present disclosure;

FIG. 7 is a schematic diagram of another phase shifting network circuit according to an embodiment of the present disclosure;

FIG. 8 is a schematic diagram of another phase shifting network circuit according to an embodiment of the present disclosure;

fig. 9 is a schematic structural diagram of another phase shifter according to an embodiment of the present application;

fig. 10 is an exemplary schematic diagram of a structure of a phase shifter according to an embodiment of the present disclosure.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all of the embodiments. All other embodiments obtained by a person of ordinary skill in the art based on the embodiments in the present application without making any creative effort belong to the protection scope of the present application.

In the embodiments of the present application, the term "plurality" means two or more, and other terms are similar thereto.

In the prior art, in order to verify the performance of a 5G communication system adopting beamforming and MIMO mode, a test may be performed by a conduction test method. The existing conduction testing method is to use an active phase shifter to simulate the transmission multipath of the MIMO, and beam forming at any angle can be realized through the active phase shifter, but the active phase shifter has a complex structure and higher cost, and needs to be calibrated before use, so that the use is more complex. Therefore, the embodiment of the application provides a phase shifter and a base station test system, the phase shifter is a passive fixed phase shifter, the structure is simple, the cost is low, and calibration is not needed before use.

The 5G system implements an MIMO mode by using an array antenna of a Frequency Division Duplex (FDD) base station, and a beam forming principle of the array antenna is shown in fig. 1. Taking a linear array as an example, an array antenna includes n antenna elements, and the distance between adjacent antenna elements is d. In order to make the array antenna generate the shaped beam pointing at the angle θ, the phase difference between the radio frequency signals of each antenna unit needs to be φ, φ is 2 π d sin θ/λ. Where λ is the wavelength.

Based on the principles illustrated in fig. 1, an array antenna pattern test may be performed. The array antenna directional diagram test is that radio frequency signals with different amplitudes and phases are input into different antenna units, so that the array antenna generates beams in different directions, signal intensity in each direction of a space can be obtained through antenna directional diagram measurement, a relation diagram of two-dimensional or three-dimensional radiation signal intensity and direction is drawn, and the performance of the 5G communication system can be determined by comparing the relation diagram with a simulation result.

The MIMO mode is based on the principle shown in fig. 2, taking a 2x2 multi-user MIMO system as an example, where the number of antenna output ports on the base station side is 2, the number of antenna input ports of the terminal is 2, and the number of transmission multipaths between the base station and the terminal is the product of the number of antenna output ports of the base station and the number of antenna input ports of the terminal, i.e., 2x 2.

Let the received signal vector be y, the transmitted signal vector be x, and the spatial transfer function of the MIMO system be h, then y ═ h × x, and properly design the transmitted signal vector, so that terminal 1 can only receive the signals that the base station needs to send to terminal 1, and terminal 2 can only receive the signals that the base station needs to send to terminal 2. The specific implementation principle can refer to the description in the related art.

In the embodiment of the present application, the phase shifter may simulate multipath transmission between the base station and the terminal, and the phase shifter provided in the embodiment of the present application is described in detail below.

As shown in fig. 3, an embodiment of the present application provides a phase shifter, including: the phase-shifting circuit comprises M signal input circuits, N signal output circuits and a phase-shifting network circuit arranged between the signal input circuits and the signal output circuits; wherein M and N are integer multiples of 2.

As an example, M may be the same number of antenna interfaces of the base station, and N may be the same number of antenna interfaces of the terminal.

The phase-shifting network circuit comprises M power dividers, N combiners and M multiplied by N strip lines between the M power dividers and the N combiners, wherein the length of each strip line included in the phase-shifting network circuit is determined based on a plurality of different beam forming angles included by test requirements, and the strip lines correspond to the beam forming angles one to one.

The power divider is a 1-dividing N power divider, and the combiner is an M-in-1 combiner. The 1-division-N power divider may be formed by combining a plurality of 1-division-2 power dividers, and the M-in-1 combiner may be formed by combining a plurality of 2-in-1 combiners.

Taking the values of M and N as 4 as an example, the phase shift network circuit in fig. 3 is shown in fig. 4, and the phase shift network circuit includes 4 1-to-4 power splitters, 4-to-1 combiners, and 4 × 4 strip lines.

By adopting the technical scheme, the phase shifter comprises M signal input circuits, N signal output circuits and a phase shifting network circuit, wherein the phase shifting network circuit comprises M power dividers, N combiners and M multiplied by N strip lines between the M power dividers and the N combiners. It can be seen that the phase shifter in the embodiment of the present application includes a simple circuit, and the length of the strip line is set based on the test requirement, so that a plurality of beam forming angles required by the test can be realized, a complex structural design is not required, devices such as an attenuator are not required, the structure is simple, and the cost is low.

In one embodiment of the present application, the phase shifter is embodied as a Printed Circuit Board (PCB). The M signal input circuits, the N signal output circuits, the M power dividers and the N combiners are all positioned on a first metal wiring layer of the PCB;

the strip line is located on a first metal wiring layer and a second metal wiring layer of the PCB, the first metal wiring layer is provided with a via hole, and the via hole is used for communicating the same strip line on the first metal wiring layer and the second metal wiring layer.

The PCB is a 4-layer board, wherein the top layer and the bottom layer are reference layers, the middle two layers are metal wiring layers, one of the middle two layers is the first metal wiring layer, and the other layer is the second metal wiring layer.

The embodiments of the present application provide two types of M power dividers, N combiners, and two types of M × N strip lines between the M power dividers and the N combiners, which are respectively described below.

In the first distribution scheme, as shown in fig. 5, M power dividers are sequentially arranged on one side of the first metal wiring layer, N combiners are sequentially arranged on the other side of the first metal wiring layer, and the M power dividers are opposite to the N combiners. For example, M power splitters are sequentially arranged on the left side of the first metal wiring layer, and accordingly, N power combiners are sequentially arranged on the right side of the first metal wiring layer.

In fig. 5, taking M and N as 4 as examples, fig. 5 includes 4 1-division-4 power dividers and 4-in-1 combiners, each 1-division-4 power divider includes 3 1-division-2 power dividers, and each 4-in-1 combiner includes 3 2-in-1 combiners.

All the horizontal lines shown in fig. 5 are located on the first metal wiring layer, the vertical lines are located on the second metal wiring layer, and the turning points between the horizontal lines and the vertical lines are vias on the first metal wiring layer.

In this embodiment of the application, the via hole on the side close to the power divider and the via hole on the side close to the combiner on the first metal wiring layer are symmetrically arranged with respect to the first central line. The first central line is a central line between a column where the M power dividers are located on the first metal wiring layer and a column where the N combiners are located.

Referring to fig. 5, the first center line is a center line between a column in which 4 power dividers on the left side are located and a column in which 4 power dividers on the right side are located.

In a conventional routing manner, a complete stripline between two rf ports is in the same metal layer of the PCB, and for the ports of 4 × 4, as shown in fig. 6, if a conventional routing scheme is adopted, 4 metal wiring layers are required, and the striplines connected to each combiner are respectively located on 1 metal wiring layer, for example, in fig. 6, 4 striplines connected to a first combiner are in the first metal wiring layer, 4 striplines connected to a second combiner are in the second metal wiring layer, 4 striplines connected to a third combiner are in the third metal wiring layer, and 4 striplines connected to a fourth combiner are in the fourth metal wiring layer. For a PCB comprising 4 metal routing layers, 5 reference layers are usually also included, i.e. it needs to be implemented by a 9-layer PCB. In the embodiment of the application, a complete strip line is connected through the via hole, and only 2 layers of metal wiring layers and 2 layers of reference layers are needed, so that the implementation can be realized through 4 layers of PCBs, and the cost is saved compared with 9 layers of PCBs.

In addition, in the technical scheme, the via hole on the side close to the power divider and the via hole on the side close to the combiner on the first metal wiring layer are symmetrically arranged relative to the first central line, so that insertion loss and phase shift caused by the via holes can be offset, and the influence of the via holes on the performance of the phase shifter is avoided.

In a second distribution manner, as shown in fig. 7 and 8, M/2 power dividers included in the phase shift network circuit are sequentially arranged on one side of the first metal wiring layer, and M/2 power dividers are sequentially arranged on the other side of the first metal wiring layer; the N combiners are sequentially arranged between the two rows of power dividers, half input ports of each combiner face to the power divider on one side, and the other half input ports face to the power dividers on the other side.

The N combiners are sequentially arranged on the second central lines of the two rows of power dividers; or the N combiners are staggered relative to the second central line. The via holes on two sides of each combiner on the first metal wiring layer are symmetrically arranged relative to the second central line.

Referring to fig. 7, in fig. 7, taking M and N as 4 as an example, the left side in fig. 7 includes two 1-division-4 power dividers, the right side in fig. 7 includes two 1-division-4 power dividers, and the second center lines of the two rows of power dividers include 4 combiners 4-to-1.

In the actual PCB, the length relationship of each strip line is not limited to the length relationship shown in fig. 7, and each strip line is not limited to a straight line, for example, the length of the strip line may meet the test requirement by bending or the like.

Referring to fig. 8, taking both M and N as 4 in fig. 8 as an example, the left side in fig. 8 includes two 1-division-4 power splitters, the right side includes two 1-division-4 power splitters, and the 4-to-1 combiners are staggered with respect to the second center lines of the two columns of power splitters.

The connection lines shown in fig. 8 are strip lines between the power divider and the combiner, fig. 8 is only a schematic diagram, and in an actual PCB, the length relationship of the strip lines is not limited to the length relationship shown in fig. 8. The test requirements can be met by adjusting the distance of each combiner from the second centerline in fig. 8.

In this application embodiment, through making N combiners arrange in order between two merit branches, and half input port of every combiner divide the ware towards the merit of one side, and half input port divides the ware towards the merit of opposite side in addition, can reduce the horizontal line between merit branch ware and the combiner and erect the line turn, reduces via hole quantity, and can reduce the wiring degree of difficulty, save the PCB area, further reduce cost.

In addition, the length of each strip line meets the test requirement by the mode that each combiner is staggered relative to the second central line, the bending of the strip line can be reduced, and the wiring difficulty is reduced.

In the above embodiments of the present application, the combiner and the power divider are relative concepts, and if the input of the power divider is used as the output and the output of the power divider is used as the input, the power divider can be used as the combiner.

The phase shift network circuit may be an uplink phase shift network circuit or a downlink phase shift network circuit, for example, the phase shift network circuits shown in fig. 5 to 8 may be all downlink phase shift network circuits, and if the combiner in fig. 5 to 8 is used as a power divider and the power divider in fig. 5 to 8 is used as a combiner, the phase shift network circuit may be an uplink phase shift network circuit.

The phase shifter comprising the uplink phase shifting network circuit can realize the measurement of an uplink from the test terminal to the test base station, and the phase shifter comprising the downlink phase shifting network circuit can realize the measurement of a downlink from the test base station to the test terminal.

In the above fig. 5 to 8, the channels a1, a2, A3 and a4 are four radio frequency channels of the test base station, and the channels B1, B2, B3 and B4 are four radio frequency channels of the test terminal.

In another embodiment of the present application, a base station test system is further provided, where the base station test system includes a test base station, a plurality of test terminals, and the phase shifter.

The M radio frequency channels of the test base station are connected with the M signal input circuits of the phase shifter one by one, and the radio frequency channels of the plurality of test terminals are connected with the N signal output circuits of the phase shifter one by one.

In order to perform measurements on the uplink and the downlink simultaneously, another phase shifter is provided in the embodiments of the present application, as shown in fig. 9, the phase shifter includes M first duplexers, N second duplexers, and an uplink phase shifting network circuit and a downlink phase shifting network circuit disposed between the M first duplexers and the N second duplexers. M and N are integer multiples of 2.

In the embodiment of the present application, each of the first duplexer and the second duplexer may be a stripline duplexer.

The uplink phase-shifting network circuit comprises M combiners, N power dividers and M multiplied by N strip lines between the M combiners and the N power dividers, wherein the length of each strip line included by the uplink phase-shifting network circuit is determined based on a plurality of different beam forming angles included by test requirements, and the strip lines included by the uplink phase-shifting network circuit correspond to the beam forming angles one to one; the combiner of the uplink phase-shifting network circuit is an N-in-1 combiner, and the power divider of the uplink phase-shifting network circuit is a 1-division-M power divider;

the downlink phase shift network circuit comprises M power dividers, N combiners and M multiplied by N strip lines between the M power dividers and the N combiners, wherein the length of each strip line included in the downlink phase shift network circuit is determined based on a plurality of different beam forming angles included by test requirements, and the strip lines included in the downlink phase shift network correspond to the beam forming angles one to one; the power divider included in the downlink phase-shifting network circuit is a 1-to-N power divider, and the combiner included in the downlink phase-shifting network circuit is an M-to-1 combiner;

each first duplexer is respectively connected to the input of one power divider in the uplink phase-shifting network circuit, the output of each power divider in the uplink phase-shifting network circuit is respectively connected to the input of one combiner, and the output of each combiner is respectively connected to one second duplexer;

each second duplexer is respectively connected to the input of one power divider in the downlink phase-shift network circuit, the output of each power divider in the downlink phase-shift network circuit is respectively connected to the input of one combiner, and the output of each combiner is respectively connected to one first duplexer.

In an embodiment of the present application, the M first duplexers, the N second duplexers, the M combiners and the N power dividers included in the uplink phase-shift network circuit, and the M power dividers and the N combiners included in the downlink phase-shift network circuit are all located on a first metal wiring layer of a printed circuit board PCB;

In one implementation, in the uplink phase-shifting network circuit, M combiners are sequentially arranged on one side of the first metal wiring layer, and N power dividers are sequentially arranged on the other side of the first metal wiring layer; or M/2 combiners are sequentially arranged on one side of the first metal wiring layer, the other M/2 combiners are sequentially arranged on the other side of the first metal wiring layer, and the N power dividers are sequentially arranged on the central lines of the two columns of combiners or staggered relative to the central lines of the two columns of combiners;

in the downlink phase-shifting network circuit, M power dividers are sequentially arranged on one side of a first metal wiring layer, and N combiners are sequentially arranged on the other side of the first metal wiring layer; or, M/2 power dividers are sequentially arranged on one side of the first metal wiring layer, the other M/2 power dividers are sequentially arranged on the other side of the first metal wiring layer, and the N combiners are sequentially arranged on the central lines of the two rows of power dividers, or are staggered relative to the central lines of the two rows of power dividers.

By adopting the technical scheme, the phase shifter can be realized through the duplexer, the power divider and the combiner, the realization is simpler, the required cost is lower, the length of the strip line is set based on the test requirement, a plurality of beam forming angles required by the test can be realized, the complex structural design is not required, and the simultaneous measurement of the uplink and the downlink can be realized through the phase shifter.

The phase shifter according to the embodiment of the present application is described below with reference to a specific example, as shown in fig. 10, the phase shifter includes 4 first duplexers, the two first duplexers on the left side are respectively connected to the rf path a1 and the rf path A3 of the testing base station, and the two first duplexers on the right side are respectively connected to the rf path a2 and the rf path a4 of the testing base station. Each duplexer includes a transmitting end and a receiving end. For ease of understanding, the two first duplexers on the left side are referred to as duplexer a1 and duplexer A3, respectively, and the two first duplexers on the right side are referred to as duplexer a2 and duplexer a4, respectively.

The phase shifter further includes 4 second duplexers respectively connected to the radio frequency channels B1, B2, B3, and B4 of the test terminal. For convenience of understanding, the above-described 4 duplexers are referred to as a duplexer B1, a duplexer B2, a duplexer B3, and a duplexer B4, respectively.

Fig. 10 shows two phase shift network circuits, and it can be seen that the upper and lower portions in fig. 10 have the same structure, one of which can be used as an uplink phase shift network circuit, and the other can be used as a downlink phase shift network circuit.

Taking the lower half of fig. 10 as an example of a downlink phase shift network circuit, referring to fig. 10, the transmitting end of the duplexer a1 in fig. 10 is connected to the input of the power divider a1, and 4 outputs of the power divider a1 are connected to the inputs of the combiner B1, the combiner B2, the combiner B3, and the combiner B4, respectively.

The transmitting terminal of the duplexer a2 is connected to the input of the power divider a2, and 4 outputs of the power divider a2 are connected to the inputs of the combiner B1, the combiner B2, the combiner B3, and the combiner B4, respectively.

The transmitting terminal of the duplexer A3 is connected to the input of the power divider A3, and 4 outputs of the power divider A3 are connected to the inputs of the combiner B1, the combiner B2, the combiner B3, and the combiner B4, respectively.

The transmitting terminal of the duplexer a4 is connected to the input of the power divider a4, and 4 outputs of the power divider a4 are connected to the inputs of the combiner B1, the combiner B2, the combiner B3, and the combiner B4, respectively.

The duplexers in fig. 10 are all duplexers implemented by PCB strip lines, and as an example, the uplink frequency band of the duplexer is 1.92-1.98GHz, and the downlink frequency band of the duplexer is 2.11-2.17 GHz.

The phase shifter shown in fig. 10 includes 16 transmission paths between the input ports of the 4 duplexers and the output ports of the 4 duplexers, and the length of each transmission path can be determined according to the beamforming angle determined by the test requirement. Wherein, the relationship between the length of the transmission path and the angle of the beam forming is: l is phi x lambda/360, L is the transmission path length, phi is the beamforming angle, and lambda is the wavelength.

In order to reduce the wiring difficulty of the PCB, in the embodiment of the present application, a distance between each first duplexer and the uplink phase shift network circuit and a distance between each second duplexer and the uplink phase shift network circuit are the same. And the distance between each first duplexer and the downlink phase-shifting network circuit and the distance between each second duplexer and the downlink phase-shifting network circuit are the same. Furthermore, the length difference of the strip line between the power divider and the combiner is set, so that the length of the transmission path corresponding to the test requirement can be met.

As an example, the relationship between the path length of the above 16 transmission paths and the beamforming angle is shown in table 1.

TABLE 1

It is noted that, herein, relational terms such as first and second, and the like may be used solely to distinguish one entity or action from another entity or action without necessarily requiring or implying any actual such relationship or order between such entities or actions. Also, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in a process, method, article, or apparatus that comprises the element.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the scope of the present invention. Any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention shall fall within the protection scope of the present invention.

Claims

1. A phase shifter, comprising: the phase-shifting circuit comprises M signal input circuits, N signal output circuits and a phase-shifting network circuit arranged between the signal input circuits and the signal output circuits; m and N are integer multiples of 2;

each signal input circuit is connected with the input of one power divider; the output of each power divider is respectively connected with the input of one combiner; the output of each combiner is respectively connected with a signal output circuit.

2. The phase shifter of claim 1, wherein the M signal input circuits, the N signal output circuits, the M power dividers, and the N combiners are all located at a first metal wiring layer of a Printed Circuit Board (PCB);

the strip line is located on the first metal wiring layer and the second metal wiring layer of the PCB, a via hole is formed in the first metal wiring layer, and the via hole is used for communicating the same strip line on the first metal wiring layer and the second metal wiring layer.

3. The phase shifter according to claim 2,

the M power dividers are sequentially arranged on one side of the first metal wiring layer, the N combiners are sequentially arranged on the other side of the first metal wiring layer, and the M power dividers are opposite to the N combiners in position.

4. The phase shifter according to claim 3,

the via holes on the side, close to the power dividers, of the first metal wiring layer and the via holes on the side, close to the combiners, of the first metal wiring layer are symmetrically arranged relative to a first central line, and the first central line is a central line between a column where the M power dividers are located and a column where the N combiners are located on the first metal wiring layer.

5. The phase shifter according to claim 2,

m/2 power dividers included in the phase-shift network circuit are sequentially arranged on one side of the first metal wiring layer, and the other M/2 power dividers are sequentially arranged on the other side of the first metal wiring layer;

the N combiners are sequentially arranged between the two rows of power dividers, half input ports of each combiner face to the power divider on one side, and the other half input ports face to the power divider on the other side.

6. The phase shifter as recited in claim 5,

the N combiners are sequentially arranged on second central lines of the two columns of power dividers; or, the N combiners are staggered with respect to the second center line.

7. Phase shifter as in claim 5 or 6,

the via holes on two sides of each combiner on the first metal wiring layer are symmetrically arranged relative to the second central line.

8. A phase shifter, comprising: the phase-shifting network circuit comprises M first duplexers, N second duplexers, an uplink phase-shifting network circuit and a downlink phase-shifting network circuit, wherein the uplink phase-shifting network circuit and the downlink phase-shifting network circuit are arranged between the M first duplexers and the N second duplexers, and both M and N are integer multiples of 2;

each second duplexer is connected to the input of one power divider in the downlink phase-shift network circuit, the output of each power divider in the downlink phase-shift network circuit is connected to the input of one combiner, and the output of each combiner is connected to one first duplexer.

9. The phase shifter of claim 8, wherein the M first duplexers, the N second duplexers, the M combiners and the N power dividers included in the uplink phase shifting network circuit, and the M power dividers and the N combiners included in the downlink phase shifting network circuit are all located on a first metal wiring layer of a Printed Circuit Board (PCB);

10. The phase shifter according to claim 9,

in the uplink phase shift network circuit, the M combiners are sequentially arranged on one side of the first metal wiring layer, and the N power dividers are sequentially arranged on the other side of the first metal wiring layer; or, M/2 combiners are sequentially arranged on one side of the first metal wiring layer, the other M/2 combiners are sequentially arranged on the other side of the first metal wiring layer, and the N power dividers are sequentially arranged on the central lines of the two columns of combiners or are staggered relative to the central lines of the two columns of combiners;

11. A base station test system, characterized in that the system comprises a test base station, a plurality of test terminals and a phase shifter according to any one of claims 8-10;