Patent ID: 12255709

DETAILED DESCRIPTION OF ILLUSTRATIVE EMBODIMENTS

The technical solutions of embodiments of this application may be applied to various communications systems, such as a global system for mobile communications (GSM), a code division multiple access (CDMA) system, a wideband code division multiple access (WCDMA) system, a general packet radio service (GPRS), a long term evolution (LTE) system, an LTE frequency division duplex ( ) system, an LTE time division duplex (TDD) system, a universal mobile telecommunications system (UMTS), a worldwide interoperability for microwave access (WiMAX) communications system, a future 5th generation (5G) system, or a new radio (NR) system.

FIG.1Bis a schematic diagram of a structure of an antenna system according to an embodiment of this application. The antenna system includes a bridge network110and an antenna module120. Optionally, the antenna system includes a control module130, a digital signal processing module140, and a digital-to-analog conversion module150.

The antenna module120is connected to a first terminal of the bridge network110, a second terminal of the bridge network110is connected to the control module130, and a third terminal of the bridge network110is connected to one terminal of the digital-to-analog conversion module150.

The antenna module120is configured to receive and transmit an analog signal. The antenna module includes a plurality of antennas.

The bridge network110is configured to: receive an analog signal sent by the digital-to-analog conversion module150, perform first weighting processing on the analog signal, and transmit the processed analog signal by using the antenna module120; or is configured to: receive the analog signal sent by the antenna module120, perform third weighting processing on the analog signal, and then output the processed analog signal. The bridge network110includes n bridge modules, where n is an integer greater than or equal to 2.

The following describes the bridge network110by using an example in which the bridge network110includes a first bridge module and a second bridge module.FIG.1Cis a schematic diagram of a structure of a bridge network and an antenna module according to an embodiment of this application. The bridge network110includes the first bridge module and the second bridge module, the antenna module120includes a first antenna and a second antenna, a fourth port of the first bridge module is connected to the first antenna, and a fourth port of the second bridge module is connected to the second antenna. A third port of the first bridge module is connected to a second port of the second bridge module by using a first line length, and a third port of the second bridge module is connected to a second port of the first bridge module by using a second line length.

In this embodiment of this application, a port naming rule of the bridge module is as follows: A first port of the bridge module is configured to: receive the analog signal sent by the digital-to-analog conversion module150, or send the analog signal sent by the digital-to-analog conversion module150. A second port of the bridge module is configured to be connected to a third port of a bridge module connected to the second port of the bridge module. A third port of the bridge module is configured to be connected to a second port of a bridge module connected to the third port of the bridge module. A fourth port of the bridge module is configured to: receive an analog signal sent by an antenna connected to a fourth port of the bridge module, or send an analog signal to an antenna connected to a fourth port of the bridge module.

The control module130is configured to set a line length of a connection line between the n bridge modules included in the bridge network110, to control a proportion value of output signals of first ports of the n bridge modules. For example, as shown inFIG.1C, the control module130controls the first line length and the second line length, to control a proportion value of an output signal of the fourth port of the first bridge module to an output signal of the fourth port of the second bridge module.

The digital signal processing module140is configured to: receive a digital signal; perform second weighting processing on the digital signal, to obtain a processed digital signal; and convert the processed digital signal into an analog signal, and send the analog signal to the bridge network110; or is configured to: receive the analog signal sent by the digital-to-analog conversion module150, convert the analog signal into a digital signal, perform fourth weighting processing on the digital signal, and then output the processed digital signal.

With reference toFIG.1D, the following describes a schematic diagram of a scenario in which the antenna system in this embodiment of this application is applied to an access network device. The access device may include an evolved NodeB (eNB), a radio network controller (RNC), a NodeB (NB), a base station controller (BSC), a base transceiver station (BTS), a home NodeB (for example, a home evolved NodeB, or a home NodeB, HNB), a baseband unit (BBU), or an access point (AP), a wireless relay node, a wireless backhaul node, a transmission point ((TP) or transmission and reception point (TRP)), or the like in a Wi-Fi system, or may be a gNB or a transmission point (TRP or TP) in a 5G system, for example, an NR system, one or a group (including a plurality of antenna panels) of antenna panels of a base station in the 5G system, or may be a network node constituting a gNB or a transmission point, for example, a baseband unit (BBU), a distributed unit (DU), or the like.

In some deployments, the gNB may include a centralized unit (CU) and a DU. The gNB may further include a radio frequency unit (RU). The CU implements some functions of the gNB, and the DU implements some functions of the gNB. For example, the CU implements functions of a radio resource control (RRC) layer and a packet data convergence protocol (PDCP) layer, and the DU implements functions of a radio link control (RLC) layer, a media access control (MAC) layer, and a physical (PHY) layer. Information at the RRC layer eventually becomes information at the PHY layer, or is converted from information at the PHY layer. Therefore, in this architecture, it may also be considered that higher layer signaling such as RRC layer signaling or PHCP layer signaling is sent by the DU, or sent by the DU+RU. It may be understood that the network device may be a CU node, a DU node, or a device including the CU node and the DU node. In addition, the CU may be classified as a network device in an access network RAN, or the CU may be classified as a network device in a core network CN. This is not limited herein. An access network device in a wired communications system may include a passive optical network (PON), a high-speed digital subscriber line (HDSL), an asymmetric digital subscriber line (ADSL), an integrated digital subscriber loop that has a V5interface, and the like.

FIG.1Dis a schematic diagram of another structure of an antenna system according to an embodiment of this application. The antenna system includes a bridge network110, an antenna module120, a control module130, a remote radio unit160, and a baseband processing unit170. The digital signal processing module140shown inFIG.1Bis integrated into the baseband processing unit170, and a digital-to-analog conversion function of the digital-to-analog conversion module150shown inFIG.1Bis provided by the remote radio unit160.

A first terminal of the bridge network110is connected to the antenna module120, a second terminal of the bridge network110is connected to the control module130, a third terminal of the bridge network110is connected to a first terminal of the remote radio unit160, and a first terminal of the baseband processing unit170is connected to a second terminal of the remote radio unit160.

The antenna module120is configured to receive and transmit an analog signal. The antenna module includes a plurality of antennas.

The bridge network110is configured to: receive an analog signal sent by the remote radio unit160, perform first weighting processing on the analog signal, and transmit the processed analog signal by using the antenna module120; or is configured to: receive the analog signal sent by the antenna module120, perform third weighting processing on the analog signal, and then output the processed analog signal to the remote radio unit160.

The control module130is configured to set a line length of a connection line between n bridge modules included in the bridge network110, to control a proportion value of output signals of first ports of the n bridge modules.

The remote radio unit160is configured to: receive a digital signal sent by the baseband processing unit170, convert the digital signal into an analog signal, and send the analog signal to the bridge network110.

The baseband processing unit170is configured to: receive a digital signal, perform second weighting processing on the digital signal, and send the processed digital signal to the remote radio unit160; or receive a digital signal sent by the remote radio unit160, and perform fourth weighting processing on the digital signal, to obtain a processed digital signal.

It should be noted that, when performing weighting processing on the digital signal, the baseband processing unit170may perform weighting processing before or after baseband processing. This is not specifically limited in this application.

Before the bridge network provided in this embodiment of this application is described, a sequence number of a bridge module in this embodiment of this application is first described. Referring toFIG.1E, the bridge network includes n bridge modules. A 1stbridge module is a 1stbridge module in left-to-right bridge modules in the bridge network, a 2ndbridge module is a 2ndbridge module in the left-to-right bridge modules in the bridge network, and so on. In addition, the 1stbridge module is connected to a 1stantenna in n antennas, the 2ndbridge module is connected to a 2ndantenna in the n antennas, and by analogy, an nthbridge module is connected to an nthantenna in the n antennas.

FIG.1Eis a schematic diagram of a scenario in which an antenna system transmits an analog signal according to an embodiment of this application. InFIG.1E, the bridge network110includes the n bridge modules, a third port of the 1stbridge module in the n bridge modules is connected to a second port of the nthbridge module in the n bridge modules, a third port of an ithbridge module in the n bridge modules is connected to a second port of an (i−1)thbridge module in the n bridge modules, and fourth ports of the n bridge modules are respectively connected to the n antennas, where i is an integer greater than or equal to 2 and less than or equal to n, and n is an integer greater than or equal to 2.

The 1stbridge module performs first weighting processing on a first analog signal input at a first port of the 1stbridge module and a second analog signal input at a second port of the 1stbridge module, to obtain a first component and a second component. The 1stbridge module outputs the first component at a fourth port of the 1stbridge module, and inputs, at the third port of the 1stbridge module, the second component to the second port of the nthbridge module, to use the second component as a second analog signal of the second port of the nthbridge module.

A kthbridge module performs first weighting processing on a first analog signal input at a first port of the kthbridge module and a second analog signal input at a second port of the kthbridge module, to obtain a first component and a second component. The kthbridge module outputs the first component at a fourth port of the kthbridge module, and inputs, at a third port of the kthbridge module, the second component to a second port of a (k−1)thbridge module, to use the second component as a second analog signal of the second port of the (k−1)thbridge module, where k is an integer greater than 1 and less than or equal to n.

First analog signals input at first ports of the bridge modules included in the bridge network are represented as

[p0p1…pn-1],
and analog signals output at the fourth ports of the bridge modules included in the bridge network are represented as

[P0P1…Pn-1].
In this case, the analog signals output at the fourth ports of the bridge modules included in the bridge network are equal to values obtained by multiplexing the analog signals input at the first ports of the bridge modules included in the bridge network by a first weighting matrix Umatrix. In other words,

[P0P1…Pn-1]=Umatrix*[p0p1…pn-1].
Herein,

Umatrix=12⁢(S-D*S(2*S-D*S)),S=[010……0……0……11000],
S is an n*n matrix, n is a quantity of bridge modules included in the antenna system,

D=[e-i⁡(2⁢πδ0)0…00e-i⁡(2⁢πδ1)……………000…e-i⁡(2⁢πδ⁢n-1)],
D is an n*n matrix, n is the quantity of bridge modules included in the antenna system, e−i(x)is a complex exponential function whose base is a natural number e, δ0is a wavelength trip corresponding to a line length of a connection line between the second port of the 1stbridge module and a third port of a bridge module connected to the second port of the 1stbridge module, δ1is a wavelength trip corresponding to a line length of a connection line between a second port of a 2ndbridge module and a third port of a bridge module connected to the second port of the 2ndbridge module, and δn−1is a wavelength trip corresponding to a line length of a connection line between the second port of the nthbridge module and a third port of a bridge module connected to the second port of the nthbridge module. Optionally, the connection line is a microstrip.

It should be noted that, inFIG.1E, a second analog signal of a second port of each bridge module is initially a zero signal, and then after this cycle is performed, the second analog signal of the second port of the bridge module is a component input from a third port of a bridge module connected to the second port of the bridge module to the second port of the bridge module.

Different bridge modules in the bridge network in this embodiment of this application are connected in a ring connection manner, and a first analog signal input at a first port of each bridge module included in the bridge network has a corresponding output signal output at a fourth port of each bridge module, to meet an antenna signal transmission requirement such as a three-input three-output requirement, a four-input four-output requirement, or a five-input five-output requirement by using the antenna system in embodiments of this application. For example, power sharing between antenna signals of three sectors included in a base station is implemented by using the antenna system in this embodiment of this application. The antenna signals of the three sectors are respectively input to first ports of three bridge modules. Therefore, fourth ports of the three bridge modules respectively output output signals corresponding to the antenna signals of the three sectors, to implement three inputs and three outputs, thereby improving practicability of the antenna system in an actual application.

FIG.1Fis a schematic diagram of a scenario in which an antenna system receives an analog signal according to an embodiment of this application. InFIG.1F, the bridge network110includes n bridge modules, a third port of a 1stbridge module in the n bridge modules is connected to a second port of an nthbridge module in the n bridge modules, a third port of an ithbridge module in the n bridge modules is connected to a second port of an (i−1)thbridge module in the n bridge modules, and fourth ports of the n bridge modules are respectively connected to n antennas, where i is an integer greater than or equal to 2 and less than or equal to n, and n is an integer greater than or equal to 2.

The nthbridge module performs third weighting processing on a third analog signal input at a third port of the nthbridge module and a fourth analog signal input by an nthantenna in the n antennas to a fourth port of the nthbridge module, to obtain a third component and a fourth component; and the nthbridge module outputs the third component at a first port of the nthbridge module, and inputs, at the second port of the nthbridge module, the fourth component to the third port of the 1stbridge module, to use the fourth component as a third analog signal of the third port of the nthbridge module.

A jthbridge module performs third weighting processing on a third analog signal input at a third port of the jthbridge module and a fourth analog signal input by a jthantenna to a fourth port of the jthbridge module, to obtain a third component and a fourth component; and the jthbridge module outputs the third component at a first port of the jthbridge module, and inputs, at a second port of the jthbridge module, the fourth component to a third port of a (j+1)thbridge module, to use the fourth component as a third analog signal of the third port of the (j+1)thbridge module, where j is an integer greater than or equal to 1 and less than n.

Analog signals received at the fourth ports of the bridge modules included in the bridge network are represented as

[X0X1X2X3…Xn-1],
and analog signals output at the first ports of the bridge modules included in the bridge network are represented as

[x0x1x2x3……xn-1].
In this case, the analog signals output at the first ports of the bridge modules included in the bridge network are equal to values obtained by multiplexing the analog signals received at the fourth ports of the bridge modules of the bridge network by a third weighting matrix UmatrixH. In other words,

[x0x1x2x3……xn-1]=UmatrixH*[X0X1X2X3…Xn-1].
Herein, UmatrixHis obtained by performing conjugate transposition on Umatrix.

It should be noted that, inFIG.1F, a third analog signal of a third port of each bridge module is initially a zero signal, and then after this cycle is performed, the third analog signal of the third port of the bridge module is a component input from a second port of a bridge module connected to the third port of the bridge module to the third port of the bridge module.

In this embodiment, the bridge module includes n bridge modules. When a quantity of to-be-input analog signals is less than n, the to-be-input analog signals may be input only at corresponding ports of some bridge modules, and it may be considered that a zero signal is input to a corresponding port of a remaining bridge module.

In this embodiment, a matrix form of an internal structure of the bridge module may be

22[1j1-j]⁢or⁢22[1jj1].
Herein, a parameter j represents an imaginary unit, an imaginary part of j is a positive integer 1, and correspondingly, an imaginary part of −j is a negative integer 1. For example, the first analog signal is input from the first port of the bridge module, and a phase of an analog signal output from the third port of the bridge module is 90 degrees earlier than a phase of an analog signal output from the third port of the bridge module. The second analog signal is input from the second port of the bridge module, and a phase of an analog signal output from the fourth port of the bridge module is 90 degrees earlier than a phase of an analog signal output from the third port of the bridge module.

The following describes a derivation process of

Umatrix=12⁢(S-D*S(2*S-D*S))
with reference toFIG.1G. Referring toFIG.1G, the following formula may be obtained.

[P⁢01P⁢02]=[1j1-j][100e-i⁡(2⁢πδ0)][p⁢02p⁢11].
Herein,

V=[1j1-j]
is defined. In this case, a relationship between output signals of a third port and a fourth port of each bridge module inFIG.1Gand input signals of a first port and a second port of the bridge module may be learned of. For example, inFIG.1G, output signals of a third port and a fourth port of a 2ndbridge module are

[P⁢11P⁢12]=V[100e-i⁡(2⁢πδ1)][p⁢12p⁢21],
and output signals of a third port and a fourth port of an (n+1)thbridge module are

[Pn⁢1Pn⁢2]=V[100e-i⁡(2⁢πδn)][pn⁢1P⁢01].

Based on the output signals of the third port and the fourth port of each bridge module inFIG.1G, the following formula may be obtained:

[P⁢0⁢1P⁢0⁢2P⁢1⁢1P⁢1⁢2…P⁢n⁢1P⁢n⁢2]=[V0…00V00…0……0…0V][e-i(2⁢πδ0)0…00e-i⁡(2⁢πδ1)……………000…e-i⁡(2⁢πδ⁢n)][p⁢0⁢2P⁢1⁢1p⁢1⁢2P⁢2⁢1…p⁢n⁢1P⁢0⁢1](1)

Based on Formula (1), it may be learned that

[P⁢0⁢1P⁢0⁢2P⁢1⁢1P⁢1⁢2…P⁢n⁢1P⁢n⁢2]=[V0…00V00…0……0…0V][e-i(2⁢πδ0)0…00e-i⁡(2⁢πδ1)……………000…e-i⁡(2⁢πδ⁢n)]⁢([p⁢0⁢20p⁢120…pn⁢10]+[0P⁢110P⁢21…0P⁢01]).

T=[V0…00V00…0……0…0V][e-i⁡(2⁢πδ0)0…00e-i⁡(2⁢πδ1)……………000…e-1⁢(2⁢πδ⁢n)]
is defined, and it may be learned that

[P⁢0⁢1P⁢0⁢2P⁢1⁢1P⁢1⁢2…P⁢n⁢1P⁢n⁢2]=T*[[p⁢0⁢20p⁢1⁢20…p⁢n⁢10]+[0P⁢1⁢10P⁢2⁢1…0P⁢0⁢1]),and[P⁢0⁢1P⁢0⁢2P⁢1⁢1P⁢1⁢2…P⁢n⁢1P⁢n⁢2]-T*[0P⁢1⁢10P⁢2⁢1…0P⁢0⁢1]=T*[p⁢0⁢20p⁢1⁢20…p⁢n⁢10].R=[0010]
is defined, and
it may be learned that

[0P⁢1⁢10P⁢2⁢1…0P⁢0⁢1]=[00000…0000100…0000001…0000000…0000000…0000000…1000000…0010000…00][P⁢0⁢1P⁢0⁢2P⁢1⁢1P⁢1⁢2…P⁢n⁢1P⁢n⁢2]=[0R0…000R…0000…0000…RR00…0][P⁢01P⁢0⁢2P⁢11P⁢12…Pn⁢1P⁢n⁢2].

It can be learned from this that

(E-T*[0R0…000R…0000…0000…RR00…0])*[P⁢01P⁢0⁢2P⁢11P⁢12…Pn⁢1P⁢n⁢2]=T*[p⁢0⁢20p⁢120…pn⁢10].
Therefore, the following formula is obtained:

[P⁢01P⁢0⁢2P⁢11P⁢12…Pn⁢1P⁢n⁢2]=(E-T*[0R0…000R…0000…0000…RR00…0])-1*T*[p⁢0⁢20p⁢120…pn⁢10].(2)

Because each quantity on a right side of an equation in formula (2) is a known quantity, input signals that are of first ports of bridge modules in the bridge network and that are extracted from Formula (2) are

[p⁢0⁢2p⁢12p⁢2⁢2p⁢3⁢2…pn⁢1p⁢n⁢2],
and extracted output signals of fourth ports of the bridge modules in the bridge network are

[P⁢0⁢2P⁢12P⁢2⁢2P⁢3⁢2……P⁢n⁢2].
In this case, the following formula may be obtained through calculation:

[P⁢0⁢2P⁢12P⁢2⁢2P⁢3⁢2……P⁢n⁢2]=Umatrix*[p⁢0⁢2p⁢12p⁢2⁢2p⁢3⁢2…pn⁢1p⁢n⁢2].
Therefore, Umatrixis obtained.

Optionally, in this embodiment of this application, as shown inFIG.1B, the antenna system further includes the digital signal processing module140and the digital-to-analog conversion module150. A process in which the digital signal processing module140process a digital signal in a digital domain is described based on the bridge network shown inFIG.1E.

First, in a scenario in which the antenna system in this embodiment of this application transmits an analog signal, the digital signal processing module140receives a first multi-path digital signal, and the first multi-path digital signal is represented as

[s0s1…sm-1]
herein. The digital signal processing module140performs second weighting processing on the first multi-path digital signal, to obtain a second multi-path digital signal. Specifically, the second weighting processing is implemented by using a second weighting matrix. The second weighting matrix is an n*m matrix, n is the quantity of bridge modules included in the antenna system, m is a quantity of signals included in the first multi-path digital signal, and m is an integer greater than o and less than n. A specific representation is as follows: The second multi-path digital signal is

[S0S1…Sm-1]=Pmatrix*[s0s1…sm-1].
The second weighting matrix is Pmatrix. Then, the digital signal processing module140sends the second multi-path digital signal to the digital-to-analog conversion module150. The digital-to-analog conversion module150performs digital-to-analog conversion on the second multi-path digital signal, to obtain a first multi-path analog signal, and inputs the first multi-path analog signal to the bridge network110. The first multi-path analog signal may be first analog signals input to first ports of m of the n bridge modules in the bridge network shown inFIG.1E.

The second weighting matrix Pmatrix meets any one of the following conditions: column vectors of the second weighting matrix are orthogonal; each column vector of the second weighting matrix is orthogonal to one or more row vectors of the first weighting matrix; or the second weighting matrix is obtained by performing conjugate transposition on the first weighting matrix.

Optionally, a signal type of the first multi-path digital signal includes any one of the following: m layers of MIMO transmit signals; signals sent by m users; signals sent by m cells; or signals sent in m beam directions.

It can be learned from this that the foregoing describes the process in which the digital signal processing module140processes the digital signal in the digital domain, and such a manner is applicable to the following scenarios:

Weighting processing is performed on a plurality of layers of MIMO signals.

If there are signals of a plurality of users, a plurality of layers of MIMO signals, signals of a plurality of cells, or signals in a plurality of beam directions, and only a signal of a specific user, a specific layer of MIMO signal, a signal of a specific cell, or a signal in a specific beam direction needs to be sent, the digital signal processing module140may perform second weighting processing, to send only the signals of some users, the some layers of MIMO signals, the signals of some cells, or the signals in some beam directions.

If there is a signal of a specific user, a specific layer of MIMO signal, a signal of a specific cell, or a signal in a specific beam direction, and a signal needs to be sent to a plurality of users, a MIMO signal needs to be sent at a plurality of layers, a signal needs to be sent in a plurality of cells, or a signal needs to be sent in a plurality of beam directions, the digital signal processing module140performs second weighting processing, to send the signal to the plurality of users, send the MIMO signal at the plurality of layers, send the signal in the plurality of cells, or send the signal in the plurality of beam directions.

In a scenario in which the antenna system in this embodiment of this application receives an analog signal, as shown inFIG.1B, the antenna system further includes the digital signal processing module140and the digital-to-analog conversion module150. The process in which the digital signal processing module140process the digital signal in the digital domain is described based on the bridge network shown inFIG.1F.

The digital-to-analog conversion module150receives a second multi-path analog signal sent by the bridge network110; and performs digital-to-analog conversion on the second multi-path analog signal, to obtain a third multi-path digital signal. The digital signal processing module140receives a third multi-path digital signal sent by the bridge network110, and performs fourth weighting processing on the third multi-path digital signal, to obtain a fourth multi-path digital signal. The third multi-path digital signal is represented as

[Y0Y1…Ym-1],
the third multi-path digital signal include m signals, and m is an integer greater than or equal to 1 and less than or equal to n. Therefore, the fourth multi-path digital signal is

[y0y1…ym-1]=PmatrixH*[Y0Y1…Ym-1].
Herein, PmatrixHis a fourth weighting matrix, the fourth weighting matrix is an m*n matrix, and PmatrixHis obtained by performing conjugate transposition on Pmatrix.

The fourth weighting matrix meets any one of the following conditions: row vectors of the fourth weighting matrix are orthogonal; each row vector of the fourth weighting matrix is orthogonal to one or more column vectors of the third weighting matrix; or the fourth weighting matrix is obtained by performing conjugate transposition on the third weighting matrix.

Optionally, a signal type of the third multi-path digital signal includes any one of the following: m layers of MIMO receive signals; signals received by m users; signals received by m cells; or signals received in m beam directions.

Optionally, each bridge module is an intra-band combiner (also referred to as a 90-degree bridge), a matrix form of the intra-band combiner may be represented as

22[1j1-j]⁢or⁢22[1jj1].
Herein, a parameter j represents an imaginary unit, an imaginary part of j is a positive integer 1, and correspondingly, an imaginary part of −j is a negative integer 1.

It can be understood that the intra-band combiner changes an amplitude value of an analog signal, to change a power value of the analog signal. The bridge module included in the bridge network110may also be another bridge device that can implement the foregoing functions. In addition, a composition form of the bridge module in the bridge network110does not constitute a limitation on a structure of the bridge network110, and the bridge network110may include another bridge device.

Because a wavelength trip of an electromagnetic wave that is generated by the analog signal and that is transmitted in the microstrip has a corresponding phase, different wavelength trips have different phases, and the phase affects a value of an output component of the bridge module. Therefore, in the bridge network provided in this embodiment of this application, a length of a connection line connected between the n bridge modules may be adjusted, to control a proportion of an output component of the bridge module included in the bridge network, so as to implement power allocation between antenna signals, and implement power sharing between antenna signals.

Optionally, in this embodiment of this application, the foregoing describes a function of the control module130by using the bridge network shown inFIG.1Cas an example. The control module130is configured to control a first line length and a second line length. In a scenario in which the antenna system in this embodiment of this application transmits an analog signal, the first line length and the second line length are used to control a proportion value of an output signal at a fourth port of a first bridge module to an output signal at a fourth port of a second bridge module. In a scenario in which the antenna system in this embodiment of this application receives an analog signal, the first line length and the second line length are used to control a proportion value of an output signal at a first port of a first bridge module to an output signal at a first port of a second bridge module.

Specifically, the control module130controls a length of a microstrip of a first phase shifter to control the first line length, and controls a length of a microstrip of a second phase shifter to control the second line length. One terminal of the first phase shifter is connected to a second port of the first bridge module, the other terminal of the first phase shifter is connected to a third port of the second bridge module, one terminal of the second phase shifter is connected to a third port of the first bridge module, and the other terminal of the second phase shifter is connected to a second port of the second bridge module.

The following shows an example in which the bridge network in this embodiment of this application includes the first bridge module and the second bridge module. As shown inFIG.2A, it can be learned that output signals of fourth ports of bridge modules in the bridge network are represented as

[P0P1],
and input signals of first ports of bridge modules in the bridge network are represented as

[p0p1].
In this case, it can be learned that

[P0P1]=Umatrix*[p0p1],
and the first weighting matrix is

Umatrix=12⁢(S-D*S(2*S-D*S)).
Because the bridge network includes two bridge modules, it can be learned that

S=[0110]⁢and⁢D=[e-i⁡(2⁢πδ0)00e-i⁡(2⁢π⁢δ1)].
Herein, δ0is a wavelength trip corresponding to a second line length between the second port of the first bridge module and the third port of the second bridge module, and δ1is a wavelength trip corresponding to a first line length between the second port of the second bridge module and the third port of the first bridge module.

In a case in which the antenna system provided in this embodiment of this application receives an analog signal, as shown inFIG.2B, it can be learned that analog signals received at fourth ports of bridge modules in the bridge network are represented as

[X0X1],
and output signals of first ports of the bridge modules in the bridge network are represented as

[x0x1].
In this case, it can be learned that

[x0x1]=UmatrixH*[X0X1],Umatrix=12⁢(S-D*S(2*S-D*S)),S=[0110],and⁢D=[e-i⁡(2⁢πδ0)00e-i⁡(2⁢π⁢δ1)].

The following shows two possible structures of a three-input three-output bridge network by usingFIG.3andFIG.4.

FIG.3is a schematic diagram of a structure of a bridge network according to an embodiment of this application. The bridge network includes a first bridge module, a second bridge module, and a third bridge module. A third port of the first bridge module is connected to a second port of the third bridge module, a third port of the third bridge module is connected to a second port of the second bridge module, and a third port of the second bridge module is connected to a second port of the first bridge module. A phase difference existing when an analog signal passes through connection lines between bridge modules is 43.7 degrees.

FIG.4is a schematic diagram of another structure of a bridge network according to an embodiment of this application. The bridge network is a three-dimensional bridge apparatus. A bridge network110includes a first bridge module, a second bridge module, and a third bridge module.FIG.4(a)is a top view of a three-dimensional diagram of a bridge network. The three bridge modules are connected by using a microstrip, and a line length of the microstrip is

43.7°360⁢°
of a carrier medium wavelength, to form an annular circular circuit. A front view of the first bridge module is shown in an upper part shown inFIG.4(b).

To evenly output, to corresponding antennas through fourth ports of the three bridge modules, analog signals input to the three bridge modules, in other words, to make a proportion of output components of bridge modules in the bridge network close to 1:1, δ0, δ1, and δ2are all set to

43.7°180⁢°.
Herein, δ0is a wavelength trip corresponding to a line length of a connection line between a second port of the first bridge module and a third port of the second bridge module, δ1is a wavelength trip corresponding to a line length of a connection line between a second port of the second bridge module and a third port of the third bridge module, and δ2is a wavelength trip corresponding to a line length of a connection line between a second port of the third bridge module and a third port of the first bridge module.

An analog signal a is input to a first port of the first bridge module, an analog signal b is input to a first port of the second bridge module, and an analog signal c is input to a first port of the third bridge module. In this case, it can be learned that an analog signal A is output to a fourth port of the first bridge module, an analog signal B is output to a fourth port of the second bridge module, and an analog signal C is output to a fourth port of the third bridge module. In this case, it can be learned that

[ABC]=Umatrix*[abc],Umatrix=12⁢(S-D*S(2*S-D*S)),S=[010001100],and⁢D=[e-i⁡(2⁢πδ0)000e-i⁡(2⁢πδ1)000e-i⁡(2⁢πδ2)].
Because δ0, δ1, and δ2are all

43.7°180⁢°,
it can be learned through calculation that

Umatix=[0.6⁢0⁢6⁢00.6⁢4⁢9⁢50.4⁢5⁢9⁢30.4⁢5⁢9⁢30.6⁢0⁢6⁢00.6⁢4⁢9⁢50.6⁢4⁢9⁢50.4⁢5⁢9⁢30.6⁢0⁢6⁢0]*exp⁡(j*[-2⁢7.2⁢6⁢8⁢2-2⁢8.6⁢8⁢6⁢0105.0⁢3⁢4⁢0105.0⁢3⁢4⁢0-2⁢7.2⁢6⁢8⁢2-2⁢8.6⁢8⁢6⁢0-2⁢8.6⁢8⁢6⁢0105.0⁢3⁢4⁢0-2⁢7.2⁢6⁢8⁢2]).
Therefore, A, B, and C can be calculated.

A process in which a digital signal processing module140in this embodiment of this application processes a received digital signal is described below by using a scenario in which the digital signal processing module140of the bridge network shown inFIG.3orFIG.4processes an analog signal a, an analog signal b, and an analog signal c.

The digital signal processing module140receives a digital signal acof a first cell, a digital signal bcof a second cell, and a digital signal Ccof a third cell. The digital signal processing module140performs signal processing on ac, bc, and cc, for example, multiplies the digital signals by a matrix obtained by performing conjugate transposition on a first weighting matrix. Details are as follows:

[adbdcd]=UmatrxH*[acbccc],
where UmatrixHis obtained by performing conjugate transposition on Umatrix.

Optionally, ac, bc, and ccare signals of the three cells. If only a signal of the first cell is sent, signal power of the second cell and the third cell may be shared with the first cell. For example, three times of power amplification are performed on a first column vector of UmatrixH, or a power level of a digital signal of the first cell is not limited within 1, and an amplitude of acmay be amplified by √{square root over (3)} times. In this case, three digital signals may be represented as

[acbccc]=3*[ac00].

Then, a digital-to-analog conversion module150performs digital-to-analog conversion on the three processed digital signals, which may be specifically represented as follows:

[abc]=P⁡([adbdcd])=[PA000PB000P⁢c][adbdcd]

Because power (an average value) of the digital signal does not exceed 1,

[PA000PB000P⁢c]
indicates energy or a rated power level carried by each signal after digital-to-analog conversion. Herein, specifications of devices used for the three signals are the same, and rated power levels carried by the three signals are uniformly PA. Therefore,

[abc]=PA[adbdcd].

Therefore, it can be learned from the foregoing that

[adbdcd]=UmatrxH*[acbccc].
Therefore,

[abc]=PA*U⁢m⁢a⁢t⁢r⁢xH*3*[ac00].
Therefore, the analog signals a, b, and c pass through the bridge network shown inFIG.3orFIG.4, and output signals output at fourth ports of bridge modules in the bridge network are

[ABC]=Umatrx*PA*U⁢m⁢a⁢t⁢r⁢xH*3*[ac00]=3*PA*ac.

It can be learned from this that, an amplitude of an analog signal sent in the first cell (namely, a first antenna) is increased by √{square root over (3)} times, and in this way, available power of the analog signal in the first cell is increased by three times.

An embodiment of this application further provides an access network device. The access network device includes the antenna system shown inFIG.1BorFIG.1D. The antenna system is configured to perform embodiments shown inFIG.1E,FIG.1F,FIG.2A,FIG.2B,FIG.3, andFIG.4. Details are not described herein again.

The foregoing embodiments are merely intended for describing the technical solutions of this application, but not for limiting this application. Although this application is described in detail with reference to the foregoing embodiments, persons of ordinary skill in the art should understand that they may still make modifications to the technical solutions described in the foregoing embodiments or make equivalent replacements to some technical features thereof, without departing from the spirit and scope of the technical solutions of the embodiments of this application.