CN113676196B

CN113676196B - Communication method and device

Info

Publication number: CN113676196B
Application number: CN202010401734.6A
Authority: CN
Inventors: 王敬伦; 霍强; 杨智; 邹志强; 李化加
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2020-05-13
Filing date: 2020-05-13
Publication date: 2023-02-03
Anticipated expiration: 2040-05-13
Also published as: WO2021228179A1; CN113676196A

Abstract

A communication method and device, the method includes: obtaining interference channel information from a plurality of transmitting antennas to a passive intermodulation PIM source, processing downlink signals according to the interference channel information, and then sending the processed downlink signals. By adopting the technical scheme, the network equipment can avoid exciting the passive intermodulation source through the descending airspace degree of freedom, and effectively restrain the passive intermodulation signal at the descending transmitting end, so that the generation of the passive intermodulation interference signal is avoided, the performance of a communication system is effectively improved, and the utilization rate of wireless resources is improved.

Description

Communication method and device

Technical Field

The present application relates to the field of wireless communication technologies, and in particular, to a communication method and apparatus.

Background

Due to the influence of non-ideal factors such as the analog device (e.g., cable, duplexer, cable) of the communication system itself or the external transmission environment (e.g., metal device near the antenna), the downlink transmission signal may generate an additional passive inter-modulation (PIM) signal and reflect the additional passive inter-modulation (PIM) signal back to the receiving end of the system. The receiver receives the PIM signal if it happens to fall within the reception band of the upstream receiver. The PIM signal may cause interference to the uplink received signal, so that the quality of the uplink received signal is degraded, and further, the capacity of the system is reduced or the available frequency band of the system is narrowed.

The existing PIM cancellation technology can pre-estimate the PIM signal by modeling the signal in the transmit channel when transmitting the downlink signal, and then cancel the PIM signal in the receive channel. However, this approach typically performs PIM signal construction and cancellation independently in each receive antenna, which requires a PIM cancellation entity, and the complexity of each PIM cancellation entity is related to the number of transmit antennas in the communication system.

It can be seen that when applied to a multiple-input multiple-output (MIMO) system, the complexity of the method will increase dramatically as the number of transmit and receive antennas increases.

Disclosure of Invention

The embodiment of the application provides a communication method and device, which are used for evading and exciting a passive intermodulation source through a descending airspace degree of freedom, avoiding the generation of passive intermodulation signals and further improving the receiving quality of an ascending signal.

In a first aspect, an embodiment of the present application provides a communication method, which may be performed by a network device, for example, a base station or a baseband unit BBU in the base station, and may also be performed by a component (for example, a chip or a circuit) configured in the network device, where the method includes: the network equipment acquires interference channel information from a plurality of transmitting antennas to the PIM source, processes the downlink signal according to the interference channel information, and sends the processed downlink signal.

By adopting the technical scheme, the network equipment can avoid exciting the passive intermodulation source through the descending airspace degree of freedom, and effectively restrain the passive intermodulation signal at the descending transmitting end, so that the generation of the passive intermodulation interference signal is avoided, the performance of a communication system is effectively improved, and the utilization rate of wireless resources is improved.

In one possible design of the first aspect, obtaining interference channel information from multiple transmit antennas to the PIM source may include: generating a first scanning beam set, wherein the first scanning beam set comprises a plurality of scanning beams, and the dimensionality of each scanning beam is the number of transmitting antennas; traversing each scanning beam in the first scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; and determining interference channel information according to one or more scanning beams of which the corresponding uplink PIM signals in the first scanning beam set meet set conditions.

In a possible design of the first aspect, one or more scanning beams in the first scanning beam set, for which the corresponding uplink PIM signal meets the set condition, are the scanning beams with the largest received power of the corresponding uplink PIM signal in the first scanning beam set; accordingly, determining the interfering channel information may include: and determining interference channel information according to the scanning beam with the maximum receiving power of the corresponding uplink PIM signal in the first scanning beam set.

In a possible design of the first aspect, the channel matrix corresponding to the interference channel information is a conjugate of a scanning beam with a maximum received power of the corresponding uplink PIM signal in the first scanning beam set.

In a possible design of the first aspect, the one or more scanning beams in the first scanning beam set, for which the corresponding uplink PIM signal meets the set condition, are the first S scanning beams in the first scanning beam set, where the received power of the corresponding uplink PIM signal is the largest, and S is a positive integer; accordingly, determining the interfering channel information may include: and determining interference channel information according to the first S scanning beams with the maximum receiving power of the corresponding uplink PIM signals in the first scanning beam set.

In a possible design of the first aspect, the channel matrix corresponding to the interference channel information is a conjugate of the first S scanning beams in the first scanning beam set, where the received power of the corresponding uplink PIM signal is the maximum, or is a conjugate of one or more eigenvectors of a correlation matrix of the first S scanning beams in the first scanning beam set, where the received power of the corresponding uplink PIM signal is the maximum.

In one possible design of the first aspect, generating the first set of scanning beams may include: generating a second scanning beam set, and traversing each scanning beam in the second scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; taking the second scanning beam set as an input scanning beam set of the 1 st iteration, and executing the following iterative process: in the ith iteration, selecting a scanning beam with the maximum receiving power of an uplink PIM signal corresponding to the input scanning beam set as a first scanning beam; performing orthogonalization processing on the input scanning beam set based on the first scanning beam to obtain an output scanning beam set in the ith iteration, wherein the output scanning beam set comprises scanning beams which are obtained after each scanning beam except the first scanning beam in the input scanning beam set is orthogonal to the first scanning beam; traversing the scanning beams in the output scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; if the receiving power of the uplink PIM signal corresponding to each scanning beam in the output scanning beam set meets the convergence condition or the iteration frequency reaches a first set threshold value, ending the iteration, and forming a first scanning beam selected in each iteration process into a first scanning beam set; otherwise, entering next iteration, and taking the output scanning beam set as the input scanning beam set in the next iteration.

By adopting the technical scheme, because the scanning beam set is subjected to orthogonalization processing, each scanning beam selected after iteration processing is orthogonal to each other, so that all space components of the PIM signal can be acquired, the space where the PIM interference is located can be avoided when a downlink signal is sent, and the generation of the PIM interference signal is further avoided.

In one possible design of the first aspect, generating the first set of scanning beams may include: generating a second scanning beam set, wherein the second scanning beam set comprises P scanning beams; taking the second scanning beam set as an input scanning beam set of the 1 st iteration, and executing the following iterative process: in the ith iteration, aiming at each scanning beam in an input scanning beam set, adding the scanning beam and each offset vector in a preset offset vector set respectively to obtain an output scanning beam set in the ith iteration; traversing each scanning beam in the output scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; if the first Q receiving powers with the maximum receiving power of the uplink PIM signals corresponding to the scanning beams in the output scanning beam set tend to converge or the current iteration times reach a second set threshold value, ending the iteration, and forming the first P scanning beams with the maximum receiving power of the uplink PIM signals corresponding to the output scanning beam set into a first scanning beam set; and otherwise, entering next iteration, and taking the first P scanning beams with the maximum receiving power of the corresponding uplink PIM signals in the output scanning beam set as an input scanning beam set in the next iteration.

By adopting the technical scheme, the scanning beam set is subjected to incremental reconstruction and iterative processing, so that the direction of the scanning beam in the scanning beam set is continuously close to the spatial direction of the PIM signal, the accuracy of interference channel information is effectively improved, and the interference of the PIM interference signal generated in the process of sending the downlink signal to the uplink signal is avoided.

In one possible design of the first aspect, generating the first set of scanning beams may include: and obtaining downlink channel coefficients from a plurality of transmitting antennas to the PIM source according to the channel free space loss model or the antenna electromagnetic field model, and generating a first scanning beam set according to the downlink channel coefficients.

In one possible design of the first aspect, obtaining interference channel information from multiple transmit antennas to the PIM source includes: constructing a signal model of a plurality of transmitting antennae to a PIM source and a PIM source to a plurality of receiving antennae; transmitting a plurality of groups of known signals at the plurality of transmitting antennas, and receiving uplink PIM signals respectively corresponding to each group of known signals in the plurality of groups of known signals at the plurality of receiving antennas; performing neural network training on a signal model according to the plurality of groups of known signals and the uplink PIM signals corresponding to each group of known signals; and determining the channel information according to the signal model obtained by training.

In a possible design of the first aspect, the processing the downlink signal according to the interference channel information may include: and generating a precoding matrix according to the interference channel information, and precoding the downlink signal by using the precoding matrix.

In one possible design of the first aspect, generating a precoding matrix according to the interference channel information may include: calculating a zero space of a channel matrix corresponding to the interference channel information, constructing a zero space matrix, projecting an initial precoding matrix to the zero space matrix, and generating a new precoding matrix; or, the PIM source is regarded as a virtual user in the MIMO system, and a precoding matrix is generated according to the interference channel information.

In a possible design of the first aspect, the processing the downlink signal according to the interference channel information may include: the method comprises the steps of carrying out precoding processing on downlink signals, calculating a null space of a channel matrix corresponding to interference channel information, constructing a null space matrix, projecting the downlink signals after precoding processing to the null space matrix, and obtaining the processed downlink signals.

By adopting the technical scheme, the downlink signal processing method has multiple possible implementation modes, so that the applicability of the method can be effectively improved. Specifically, a null space matrix of PIM interference is constructed according to interference channel information, and then a new pre-coding matrix is generated according to the null space matrix to pre-code downlink signals of a user, or the downlink signals subjected to pre-coding processing are projected to the null space matrix, so that the transmitted downlink signals can avoid the space where the PIM interference is located, the generation of uplink PIM signals is avoided, and the system performance is effectively improved.

In a second aspect, embodiments of the present application provide a communication apparatus, which may also have a function of implementing the network device in the first aspect or any one of the possible designs of the first aspect. The device may be a network device, or may be a chip included in the network device. The functions of the communication device may be implemented by hardware, or by hardware executing corresponding software, which includes one or more modules or units or means (means) corresponding to the above functions.

In one possible design, the apparatus structurally includes a processing module and a transceiver module, where the processing module is configured to support the apparatus to perform a function corresponding to the network device in any one of the designs of the first aspect or the first aspect. The transceiver module is configured to support communication between the apparatus and other communication devices, for example, when the apparatus is a network device, the transceiver module may send a processed downlink signal to a terminal device. The communication device may also include a memory module, coupled to the processing module, that retains the necessary program instructions and data for the device. As an example, the processing module may be a processor, the transceiver module may be a transceiver, the storage module may be a memory, and the memory may be integrated with the processor or disposed separately from the processor, which is not limited in this application.

In another possible design, the apparatus may be configured to include a processor and may also include a memory. A processor is coupled to the memory and is operable to execute the computer program instructions stored in the memory to cause the apparatus to perform the method of the first aspect described above or of any of the possible designs of the first aspect. Optionally, the apparatus further comprises a communication interface, the processor being coupled to the communication interface. When the apparatus is a network device, the communication interface may be a transceiver or an input/output interface; when the apparatus is a chip included in a network device, the communication interface may be an input/output interface of the chip. Alternatively, the transceiver may be a transceiver circuit and the input/output interface may be an input/output circuit.

In a third aspect, an embodiment of the present application provides a chip system, including: a processor coupled to a memory for storing a program or instructions which, when executed by the processor, cause the system-on-chip to implement the method of the first aspect or any of the possible designs of the first aspect.

Optionally, the system-on-chip further comprises an interface circuit for interfacing code instructions to the processor.

Optionally, the number of processors in the chip system may be one or more, and the processors may be implemented by hardware or software. When implemented in hardware, the processor may be a logic circuit, an integrated circuit, or the like. When implemented in software, the processor may be a general-purpose processor implemented by reading software code stored in a memory.

Optionally, the memory in the system on chip may also be one or more. The memory may be integrated with the processor or may be separate from the processor, which is not limited in this application. For example, the memory may be a non-transitory processor, such as a read only memory ROM, which may be integrated with the processor on the same chip or separately disposed on different chips, and the type of the memory and the arrangement of the memory and the processor are not particularly limited in this application.

In a fourth aspect, embodiments of the present application provide a computer-readable storage medium having stored thereon a computer program or instructions, which, when executed, cause a computer to perform the method of the first aspect or any one of the possible designs of the first aspect.

In a fifth aspect, embodiments of the present application provide a computer program product, which when read and executed by a computer, causes the computer to perform the method of the first aspect or any one of the possible designs of the first aspect.

In a sixth aspect, an embodiment of the present application provides a communication system, which includes the network device and at least one terminal device described in the above aspects.

Drawings

Fig. 1 is a schematic network architecture of a communication system according to an embodiment of the present application;

fig. 2 is a schematic diagram of a network device suitable for use in the embodiment of the present application;

fig. 3 is a flowchart illustrating a communication method according to an embodiment of the present application;

fig. 4 is a schematic diagram illustrating one possible implementation manner of a network device acquiring interference channel information from multiple transmitting antennas to a PIM source according to an embodiment of the present application;

fig. 5a and 5b are schematic diagrams of generating a first scanning beam set in an orthogonalization manner in an embodiment of the present application;

fig. 6 is a schematic flowchart of generating a first scanning beam set by incremental reconstruction in the embodiment of the present application;

fig. 7 is a schematic diagram illustrating another possible implementation manner of a network device acquiring interference channel information from multiple transmitting antennas to a PIM source in the embodiment of the present application;

fig. 8 is a schematic structural diagram of a communication device according to an embodiment of the present application;

fig. 9 is another schematic structural diagram of a communication device according to an embodiment of the present application.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the embodiments of the present application will be described in further detail with reference to the accompanying drawings.

The technical solution of the embodiment of the present application may be applied to various communication systems, such as a Long Term Evolution (LTE) system, a Frequency Division Duplex (FDD) system, a Time Division Duplex (TDD) system, a Universal Mobile Telecommunications System (UMTS), a global system for mobile communications (GSM), a fifth generation (5 g) mobile communication system or a New Radio (NR) system, or a future communication system or other communication systems that need to implement PIM cancellation.

Referring to fig. 1, a schematic structural diagram of a communication system provided in an embodiment of the present application is shown, where the communication system includes a network device and at least one terminal device (e.g., terminals 1 to 6 shown in fig. 1). The network device may communicate with at least one terminal device, such as terminal 1, via an Uplink (UL) and a Downlink (DL). The uplink refers to a physical layer communication link from the terminal equipment to the network equipment, and the downlink refers to a physical layer communication link from the network equipment to the terminal equipment.

Optionally, the network device has multiple transmit antennas and multiple receive antennas, and may communicate with at least one terminal device by using MIMO technology.

It should be understood that a plurality of network devices may also exist in the communication system, and one network device may provide services for a plurality of terminal devices. The network device in fig. 1 and each of a part of terminal devices or all of the terminal devices in at least one terminal device may implement the technical solution provided by the embodiment of the present application. In addition, the various terminal devices shown in fig. 1 are only some examples of terminal devices, and it should be understood that the terminal devices in the embodiments of the present application are not limited thereto.

The solutions provided herein are generally applicable to network devices in wireless communication systems, and may also be applicable to other devices or apparatuses that require PIM cancellation.

The network device, also called an access network device, mentioned in the embodiments of the present application is a device in a network for accessing a terminal device to a wireless network. The network device may be a node in a radio access network, which may also be referred to as a base station, and may also be referred to as a RAN node (or device). The network device may be an evolved NodeB (eNodeB) in an LTE system or an evolved LTE system (LTE-Advanced, LTE-a), or may also be a next generation base station (next generation NodeB) in a 5G NR system, or may also be a Node B (Node B, NB), a Base Station Controller (BSC), a Base Transceiver Station (BTS), a Transmission Reception Point (TRP), a home NodeB (e.g., home NodeB, or home B, HNB), a Base Band Unit (BBU), a WiFi Access Point (AP), a relay Node, an integrated access and background integrated (IAB ) Node or a base station in a future mobile communication system, or may also be a centralized unit (unit, CU), or a distributed unit (unit, CU), and the like. In a scenario of separate deployment of an access network device including a CU and a DU, the CU supports Radio Resource Control (RRC), packet Data Convergence Protocol (PDCP), service Data Adaptation Protocol (SDAP), and other protocols; the DU mainly supports a Radio Link Control (RLC) layer protocol, a Medium Access Control (MAC) layer protocol, and a physical layer protocol.

Illustratively, as shown in fig. 2, the network device may include a BBU, and a Remote Radio Unit (RRU) and an antenna (antenna) connected to the BBU, where the BBU is mainly responsible for baseband algorithm-related calculations, the BBU interacts with the RRU through a Common Public Radio Interface (CPRI), and the RRU is connected to the antenna through a feeder. It should be understood that fig. 2 is described by taking one BBU connected to one RRU as an example, and it should be understood that in practical applications, one BBU may be connected to one or more RRUs, and further BBUs and RRUs connected thereto may be included in the network device, which is not limited in this application.

The terminal device mentioned in the embodiment of the application is a device with a wireless transceiving function, and can be deployed on land, including indoor or outdoor, handheld, wearable or vehicle-mounted; can also be deployed on the water surface (such as a ship and the like); the terminal device may be a mobile phone, a tablet computer, a computer with a wireless transceiving function, a mobile internet device, a wearable device, a virtual reality terminal device, an augmented reality terminal device, a wireless terminal in industrial control, a wireless terminal in unmanned driving, a wireless terminal in telemedicine, a wireless terminal in a smart grid, a wireless terminal in transportation security, a wireless terminal in a smart city, a wireless terminal in a smart home, and the like.

The carrier wave (which may also be referred to as a carrier frequency) in the embodiments of the present application refers to a radio wave having a specific frequency and a certain bandwidth (e.g., 10M) for carrying a wireless signal to be transmitted. The frequency band refers to a part of spectrum resources used in wireless communication, for example, an 1800M frequency band used in an LTE system. Generally, a frequency band includes a plurality of carriers, for example, a 1800M frequency band has a bandwidth of 75M, and the frequency band may include M (M ≧ 1) carriers with a bandwidth of 20M and n (n ≧ 1) carriers with a bandwidth of 10M, and of course, other possible carrier division manners are also available, which is not limited in this application. In this application, a receive path, or transmit path, may process a signal containing at least one carrier wave.

It should be noted that, in the following description of the embodiments of the present application, the matrix is represented by upper bold letters, and lower bold lettersBold letters of (c) represent vectors, and use (·) ^H 、(·) ^T 、(·) ^* Representing a transformation of a matrix/vector by conjugate transpose, conjugate.

It should be noted that the terms "system" and "network" in the embodiments of the present application may be used interchangeably. The "plurality" means two or more, and in view of this, the "plurality" may also be understood as "at least two" in the embodiments of the present application. "at least one" is to be understood as meaning one or more, for example one, two or more. For example, the inclusion of at least one means that one, two or more are included, and does not limit which is included. For example, at least one of A, B and C are included, then A, B, C, a and B, a and C, B and C, or a and B and C are included. Similarly, the understanding of the description of "at least one" and the like is similar. "and/or" describes the association relationship of the associated objects, meaning that there may be three relationships, e.g., a and/or B, which may mean: a exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" generally indicates that the preceding and following related objects are in an "or" relationship, unless otherwise specified.

Unless stated to the contrary, the embodiments of the present application refer to the ordinal numbers "first", "second", etc., for distinguishing between a plurality of objects, and do not define the sequence, priority or importance of the plurality of objects, and the description of "first", "second", etc., does not define that the objects are necessarily different.

Please refer to fig. 3, which is a flowchart illustrating a communication method according to the present application, the method specifically includes:

step S301, the network device obtains the interference channel information from a plurality of transmitting antennas to the PIM source.

In the embodiment of the present application, the non-ideal factor for generating the passive intermodulation signal is referred to as a PIM source. The PIM source may also be referred to as a non-linear source, since passive intermodulation interference is typically caused by non-linear characteristics of various passive devices (e.g., duplexers, antennas, feed lines, rf line connectors, etc.) in the transmit path.

The interfering channel information is used to reflect the channel condition between the transmitting antenna of the network device to the PIM source, or it can be understood that the interfering channel information is used to reflect the fading condition of the signal sent from the transmitting antenna of the network device to the PIM source. Alternatively, the interference channel information may be represented by a channel matrix of PIM interference channels.

In step S301, the network device may obtain the interference channel information in many possible implementations, which will be described in detail below in consideration of space.

Step S302, the network equipment processes the downlink signal according to the interference channel information.

In one possible design, the network device may generate a precoding matrix according to the obtained interference channel information, and then process the downlink signal using the generated precoding matrix.

Specifically, after obtaining interference channel information of PIM interference, the network device may calculate a primary space vector and a null space vector of PIM interference, and then perform PIM interference suppression based on the primary space and the null space of PIM interference, so that the downlink signal falls into the null space of PIM interference.

For example, the network device constructs a corresponding channel matrix according to the obtained interference channel information. By performing Singular Value Decomposition (SVD) or orthogonalization on the channel matrix, an interference main space and a null space of the channel matrix are obtained, wherein the null space refers to a space without PIM signals, and PIM interference does not exist in the null space. Furthermore, the network device may construct a null-space matrix based on the obtained null space, and then project the initial precoding matrix to the null-space matrix to obtain a new precoding matrix. I.e. W _new ＝U*U ^H W, where U is a zero space matrix, U ^H The zero space matrix U and the initial precoding matrix W are in a conjugate transpose relationship, and W is the initial precoding matrix _new Is the new precoding matrix generated. Then, the new precoding matrix can be used to perform precoding processing on the downlink signal.

Or after obtaining the interference channel information of PIM interference, the network device may regard the PIM source as a virtual user in the MIMO system, construct an MU-MIMO model, and then generate a new precoding matrix by using a precoding scheme of MU-MIMO, so as to increase the target user power and reduce interference to the PIM source and other users, thereby suppressing PIM interference.

For example, it is assumed that the interference channels for K PIM sources are derived from the interference channel information as follows:

wherein h is _pimi ＝[h _pimi,1 ,h _pimi,2 ,…,h _pimi,M ]Indicating the interference channel information from M antennas to the ith PIM source, i =1,2, …, K, M being the number of antennas.

Meanwhile, the transmission channels of L users can be expressed as:

wherein h is _UEj ＝[h _UEj,1 ,h _UEj,2 ,…,h _UEj,M ]Representing M antennas to the jth user (i.e., UE) _j ) J =1,2, …, L.

Thus, after passing through the PIM source, the signal received by user j from the antenna is:

wherein, Y _UE Indicating a signal arriving at the user, Y _pim Representing signals arriving at a PIM source, X _j The original signal sent to user j at baseband, and Z is system interference and noise.

Accordingly, the newly generated precoding matrix for user j can be represented as:

in this way, the new precoding matrix of the user j may be used to perform precoding processing on the downlink signal of the user j.

A in the above equation 4 _j Refers to the received power strength of user j, b _j Refers to the received signal strength of the PIM source. In the embodiment of the present application, a can be adjusted according to specific optimization objectives _j And b _j The value of (A) is reasonably set. For example, a may be set so that the received signal for user j is not interfered by other users and PIM sources, and the signal passing through the PIM source is zero _j Column vectors with 1 for the jth element and 0 for the remaining elements, with dimension L, and b _j A column vector with elements all 0 is designed, with dimension K, but it should be understood that the application is not so limited.

In this embodiment, the precoding matrix may also be referred to as a weight matrix of the user. The processing of the downlink signal by using the precoding matrix may be that a new weight matrix of the user is used to weight the downlink signal of the user, so as to obtain the downlink signal after precoding.

In another possible design, the network device may also calculate a null space of a channel matrix corresponding to the interference channel information, construct a null space matrix, and then project the downlink signal subjected to the precoding processing to the null space matrix to obtain a processed downlink signal. I.e. Y _new ＝U*U ^H And Y. Wherein U is a zero space matrix, U ^H Is the conjugate transpose of the zero space matrix, Y is the precoded downlink signal, Y _new The processed downlink signal is a downlink signal obtained by projecting the precoded downlink signal to a null space matrix.

Step S303, the network device sends the processed downlink signal.

Optionally, the network device may send the processed downlink signal through multiple transmitting antennas.

Specifically, in step S301, the network device may acquire the interference channel information in multiple possible implementations as follows:

in a first possible implementation manner, as shown in fig. 4, the network device obtaining the interference channel information from the multiple transmitting antennas to the PIM source may include the following steps:

step S401, the network device generates a first scanning beam set, where the first scanning beam set includes N scanning beams, a dimension of each scanning beam is equal to the number of transmitting antennas in the network device, and N is a positive integer greater than or equal to 1.

In this embodiment, the downlink signal transmitted by the network device may be carried on two or more carriers, and thus the network device may generate the first set of scanning beams according to the two or more carriers carrying the downlink signal. Taking two carriers as an example, when the network device generates the first scanning beam set, the network device may select a transmission beam of one fixed carrier, and design a scanning beam set for another carrier; or, the network device may also design two scanning beam sets for the two carriers, respectively, and then traverse all scanning beam combinations in the two scanning beam sets to finally form one scanning beam set.

In one possible design, the network device may obtain downlink channel coefficients from the multiple transmitting antennas to the PIM source according to a preset model, and then generate the first scanning beam set according to the downlink channel coefficients. The preset model may be based on a channel free space loss model, an antenna electromagnetic field model, or other models, which is not limited in this application.

For example, the network device may generate the first set of scanned beams based on a channel free space loss model. Assuming that the channel from the antenna to the PIM source is subject to large-scale fading, the channel coefficient from the transmitting antenna to the PIM source can satisfy the following expression according to the channel free space loss model:

wherein, g _mn Representing the channel coefficients, r, of the antenna m to the PIM source n _mn G and k are channel-dependent constants for the distance of antenna M from PIM source n, M being a positive integer less than or equal to M, M being the number of transmit antennas.

Based on the channel free space loss model, after determining the position of the PIM source on the antenna panel, the network device may calculate, according to the formula 5, downlink channel coefficients from the multiple transmitting antennas to the PIM source, and further generate a first scanning beam set according to the downlink channel coefficients. Assuming that the space where the PIM source may be located is divided into I grids, where I is a positive integer, for a given PIM source I (i.e., grid I), the scanning beam corresponding to the PIM source I may be set to w _i ＝[g _1i ,g _2i ,…,g _Mi ] ^H In this way, the scanning beams corresponding to all PIM sources (i.e., all grids) may form the first scanning beam set, and the grid number I may be set reasonably according to the performance and complexity of the algorithm.

As another example, the network device may also generate the first set of scanning beams based on an antenna electromagnetic field model. Assuming that the antenna-to-PIM source channel propagation satisfies some electromagnetic field model, the transmit antenna-to-PIM source channel coefficients may satisfy the following expression:

g _mn ＝f(r _mn ) Equation 6

Wherein, g _mn Representing the channel coefficients, r, of the antenna m to the PIM source n _mn F () is an arbitrary electromagnetic field model equation for the distance of the antenna m from the PIM source n.

Based on the electromagnetic field model, after the position of the PIM source on the antenna panel is determined, the network device may calculate, by using the formula 6, downlink channel coefficients from the multiple transmitting antennas to the PIM source, and further generate a first scanning beam set according to the downlink channel coefficients. Similarly, assuming that the space where the PIM source may be located is divided into I grids, where I is a positive integer, for a given PIM source I (i.e., grid I), the scanning beam corresponding to that PIM source I may be set to w _i ＝[g _1i ,g _2i ,…,g _Mi ] ^H As such, the scanning beams corresponding to all PIM sources (i.e., all grids) may comprise the first set of scanning beams.

In another possible designThe network device may also generate a first set of scanning beams based on random beams, which first set of scanning beams then consists of several random beams, which set of scanning beams may therefore also be referred to as a random beam matrix. It is assumed that the first set of scanning beams may be denoted as W = [ W = [) ₁ ,w ₂ ,…,w _n ]Generating the first set of scanning beams based on random beams then means that each column vector w in the first set of scanning beams is _i Are all random beams with dimension M, which is the number of transmit antennas, generated based on a distribution function, which may be mean 0 and variance σ ² Or may also be [0,1 ]]Or may be other distribution functions, which are not listed here.

In another possible design, the network device may also generate the first set of scanning beams based on a fourier transform. It is assumed that the first set of scanning beams may be represented as W = [ W ] ₁ ,w ₂ ,…,w _n ]Generating the first set of scanning beams based on the fourier transform then means that each column vector w in the set of scanning beams is _i Is M, which is the number of transmit antennas, and each column vector w _i The elements in (a) are integers satisfying the following fourier transform:

wherein k is _i Has a value range of [0,1]And m has a value range of [0,M-1]J denotes the imaginary part.

In another possible design, the network device may also generate the first set of scanning beams based on single-antenna scanning beams. It is assumed that the first set of scanning beams may be denoted as W = [ W = [) ₁ ,w ₂ ,…,w _M ]Generating the first scanning beam based on the single-antenna scanning beam then means that each column vector w in the set of scanning beams is _i Are all M, which is the number of transmit antennas, and the column vector w _i The ith element of (2)The values of (a) are 1, and the values of the other elements are all 0, that is, each scanning beam in the first scanning beam set is a scanning beam of a single antenna, thereby forming a single-antenna scanning beam set.

In another possible design, as shown in fig. 5a, the network device may generate the first scanning beam set by an orthogonalization method, where the process specifically includes:

step S501, the network device generates a second scanning beam set, where the second scanning beam set may be understood as an initial scanning beam set, and includes P scanning beams, where P is a positive integer.

Step S502, traversing each scanning beam in the second scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam. Then, taking the second scanning beam set as the input scanning beam set of the 1 st iteration, the following iteration process is executed:

step S503, in the ith iteration, selecting a scanning beam with the maximum reception power of the uplink PIM signal corresponding to the input scanning beam set as a first scanning beam, and performing orthogonalization processing on the input scanning beam set based on the first scanning beam to obtain an output scanning beam set in the ith iteration.

In particular, assume that the input scan beam set of the ith iteration can be represented as W = [ W = [ W ] ₁ ,w ₂ ,…,w _p ]。

The first scan beam selected in the ith iteration may be represented as:

w _selet,i ＝SelectOne(w ₁ ,r _ulsignal (w ₁ )；w ₂ ,r _ulsignal (w ₂ )；…；w _p ,r _ulsignal (w _p ) ))) formula 8

Wherein slecteone () represents a selection function for selecting a first scanning beam, [ w ] ₁ ,r _ulsignal (w ₁ )]Representing a scanning beam w of an input set of scanning beams ₁ And its corresponding uplink PIM signal receiving signal r _ulsignal (w ₁ )，[w ₂ ,r _ulsignal (w ₂ )]、[w _p ,r _ulsignal (w _p )]And so on.

Subsequently, based on the selected first scanning beam, orthogonalization processing may be performed on the beams in the input scanning beam set except for the first scanning beam to construct a new scanning beam set, i.e. the output scanning beam set in the ith iteration, in the manner shown in fig. 5b

Since only the other scanning beams except the selected first scanning beam are processed in the process of orthogonalizing, only p-1 scanning beams are included in the output scanning beam set. It will be appreciated that as the iteration progresses, the number of scanning beams remaining in the output set of scanning beams will gradually decrease.

Step S504, traversing each scanning beam in the output scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam.

Here, traversing each scanning beam in the output scanning beam set in the ith iteration means that a downlink signal corresponding to each scanning beam is sent through a transmitting antenna, and then an uplink PIM signal generated by the downlink signal is received at a receiving end.

Step S505, if the received power of the uplink PIM signal corresponding to each scanning beam in the output scanning beam set satisfies a convergence condition, for example, the received power of the uplink PIM signal corresponding to each scanning beam in the output scanning beam set is smaller than a certain threshold, or the number of iterations reaches a first set threshold, the iteration is ended.

At this time, a first scanning beam set, i.e. a first scanning beam set W, can be constructed according to the first scanning beam selected in each iteration _select ＝[w _select,1 ,w _select,2 ,…]Wherein w is _select,1 Refers to the first scanning beam, w, selected during the 1 st iteration _select,2 Refers to the first scan beam selected during iteration 2, and so on.

And step S506, if not, taking the output scanning beam set in the ith iteration as an input scanning beam set of the next iteration, and entering the next iteration.

Therefore, due to the orthogonalization processing, in the first scanning beam set generated by the method shown in fig. 5a and 5b, every two scanning beams are orthogonal to each other, so that all spatial components of the PIM signal can be acquired by the iterative processing, and thus, when a downlink signal is sent, a space where PIM interference is located can be avoided, and generation of PIM interference signals is further avoided.

In yet another possible design, as shown in fig. 6, the network device may also generate the first scanning beam set by incremental reconstruction, where the process specifically includes:

step S601, the network device generates a second scanning beam set, where the second scanning beam set may be understood as an initial scanning beam set, where P scanning beams are included, and P is a positive integer. Then, taking the second scanning beam set as the input scanning beam set of the 1 st iteration, the following iteration process is executed:

step S602, in the ith iteration, for each scanning beam in the input scanning beam set, the scanning beam is added to each offset vector in the preset offset vector set, so as to obtain an output scanning beam set in the ith iteration.

Let us say the set of input scan beams in the ith iteration is denoted as W _inital The predetermined set of offset vectors is denoted as W _add The set of output scan beams in the ith iteration is denoted as W _scan Input set of scanned beams W _inital Comprising P scanning beams, a set of offset vectors W _add Including R offset vectors, the dimensions of the P scanning beams are the same as those of the R offset vectors, and are the number M of transmitting antennas, then the scanning beam set W will be input _inital One scanning beam w of _i And a set of offset vectors W _add Respective offset vector [ w ] of _add1 ,w _add2 ,…,w _addM ]After respective addition, a scanning beam w is obtained _i Correspond toM new scanning beams w _i +w _add1 ,w _i +w _add2 ,…,w _i +w _addR ]. The M new scanning beams can be regarded as the original scanning beams w _i Are shifted in M different directions, and thus can be considered as the original scanning beam w _i The basic M refined scan beams.

Thus, traversing the input scan beam set W _inital Will result in P x R new scan beams which form the set W of output scan beams in the ith iteration _scan 。

Through the above processing, the number of scanning beams in the output scanning beam set in the ith iteration is greater than the number of scanning beams in the input scanning beam set, and the output scanning beam set includes the sum of any scanning beam in the input scanning beam set and any offset vector in the offset vector set. Thus, the set of output scanning beams may also be referred to as a refined set of scanning beams after incremental reconstruction.

Step S603, traversing each scanning beam in the output scanning beam set in the ith iteration to obtain an uplink PIM signal corresponding to each scanning beam.

Here, traversing each scanning beam in the output scanning beam set in the ith iteration means that a downlink transmission signal corresponding to each scanning beam is transmitted through a transmitting antenna, and then an uplink PIM signal generated by the downlink signal is received at a receiving end.

Step S604, if the first Q received powers with the maximum received power of the uplink PIM signal corresponding to the scanning beam in the output scanning beam set tend to converge, or the current number of iterations reaches a second set threshold, the iteration is ended, at this time, the first P scanning beams with the maximum received power of the uplink PIM signal corresponding to the output scanning beam set may be formed into a first scanning beam set, and Q is a positive integer greater than or equal to 1.

Step S605, if not, taking the first P scanning beams with the maximum receiving power of the uplink PIM signals in the output scanning beam set as the input scanning beam set in the next iteration, and entering the next iteration.

Therefore, the direction of the scanning beam in the scanning beam set is enabled to be continuously close to the spatial direction of the PIM signal by incremental reconstruction and iterative processing, and the accuracy of the direction of the scanning beam in the first scanning beam set is effectively improved.

It should be noted that, in the two possible designs shown in fig. 5a and fig. 6, the second scanning beam set may be configured in advance, or may be a scanning beam set generated by the methods described in the foregoing several other possible designs, for example, a scanning beam set generated based on a free space loss model or an antenna physical model, a scanning beam set generated based on a random beam or a fourier transform, or a scanning beam set generated by other methods, which is not limited in the present application.

Step S402, the network device traverses the scanning beams in the first scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam.

In step S402, the network device traversing the scanning beams in the first scanning beam set means that the network device generates a downlink transmission signal corresponding to each scanning beam, transmits the downlink transmission signal to the terminal device through the transmitting antenna, and receives a corresponding uplink PIM signal through the receiving antenna.

Step S403, the network device determines the interference channel information according to one or more scanning beams in the first scanning beam set, where the corresponding uplink PIM signal satisfies a set condition.

In this embodiment, the network device may determine the interference channel information from the transmitting antenna to the PIM source according to the received power of the uplink PIM signal corresponding to each scanned beam in the first set of scanned beams.

Suppose the first set of scanning beams is W = [ W ] ₁ ,w ₂ ,…,w _n ]Then the interfering channel information may be expressed as:

h _pim ＝Map(Select(w ₁ ,r _ulsignal (w ₁ )；w ₂ ,r _ulsignal (w ₂ )；…；w _n ,r _ulsignal (w _n ) ))) 9

Wherein h is _pim Representing the interference channel information, select () being a selection function for representing that one or more scanning beams satisfying a set condition are selected from a scanning beam set included in a first scanning beam set; map () is a mapping function, which is used to represent the mapping relationship between the interference channel information from multiple transmitting antennas to the PIM source and the selected one or more scanning beams; [ w ] _i ,r _ulsignal (w _i )]Representing a scanned beam w _i And its corresponding uplink PIM signal.

In one possible design, the one or more scanning beams for which the corresponding uplink PIM signal satisfies the set condition may be the scanning beam with the highest received power of the corresponding uplink PIM signal in each scanning beam included in the first scanning beam set. Accordingly, the network device may determine the interference channel information according to the scanning beam with the maximum reception power of the corresponding uplink PIM signal.

In this scenario, the selected scanning beam with the maximum received power of the corresponding uplink PIM signal may be represented as:

the interference channel information may be expressed as:

wherein, w _select Indicating the selected scanning beam. At this time, the channel matrix corresponding to the interference channel information is a conjugate transpose of the selected scanning beam with the maximum receiving power of the corresponding uplink PIM signal.

In another possible design, the one or more scanning beams for which the corresponding uplink PIM signal meets the set condition may be the first S scanning beams included in the first scanning beam set, where S is a positive integer greater than or equal to 2, and the received power of the corresponding uplink PIM signal in each scanning beam is the largest. Accordingly, the network device may determine the interference channel information according to the first S scanning beams with the maximum received power of the selected corresponding uplink PIM signal.

In this scenario, the first S scanning beams with the maximum received power of the selected corresponding uplink PIM signal may be represented as:

the interference channel information may be expressed as:

wherein w _select Indicating the selected scanning beam.

In this case, the channel matrix corresponding to the interference channel information may be a conjugate of the first S scanning beams with the maximum received power of the selected corresponding uplink PIM signal, that is, a conjugate transpose matrix of a beam matrix formed by the S scanning beams.

Alternatively, the channel matrix corresponding to the interference channel information may also be a conjugate of one or more eigenvectors of the correlation matrix of the first S scanning beams with the largest received power of the selected corresponding uplink PIM signal. For example, the correlation matrix for the first S scanning beams may be

By applying a correlation matrix to the correlation matrix

SVD is carried out to obtain each eigenvector of the correlation matrix, and then S is taken before _p The conjugate value of the eigenvector corresponding to the largest eigenvalue is used as the interference channel information, i.e.

s _p Is a positive integer less than or equal to S, eigVec _i Is the ith feature vector.

In a second possible implementation manner, as shown in fig. 7, the network device obtaining the interference channel information from the multiple transmitting antennas to the PIM source may also include the following steps:

step S701, the network device constructs a signal model from a plurality of transmitting antennas to the PIM source and from the PIM source to a plurality of receiving antennas.

The signal model may also be referred to as a neural network model, which is used to describe the non-linear characteristics between the air interface signal of the near field and the PIM source.

Step S702, the network device transmits multiple sets of known signals through multiple transmitting antennas, and receives uplink PIM signals corresponding to each set of known signals in the multiple sets of known signals through multiple receiving antennas.

Step S703, the network device performs neural network training on the signal model according to the multiple groups of known signals and the uplink PIM signal corresponding to each group of known signals, and determines interference channel information according to the signal model obtained through training.

Optionally, the network device may perform neural network training by using an error Back Propagation (BP) algorithm.

For example, assume that there are two sets of transmit antennas, TX1 and TX2, respectively. Two groups of antennas are respectively used for sending two downlink signals x with different frequencies ₁ And x ₂ . Thus, the transmit signal from the transmit antenna to the kth PIM source can be expressed as:

wherein, the first and the second end of the pipe are connected with each other,

representing the channel information of the antenna group TX1 to the PIM source k,

representing the channel information of the antenna group TX2 to the PIM source k.

The uplink PIM signal generated after the downlink transmission signal received by the nth receiving antenna passes through the PIM source may be represented as:

wherein f is _nk Representing the channel coefficients of PIM source k to antenna n, c _k Is the nonlinear coefficient of PIM source k.

Thus, two layers of networks are constructed: a downlink transmit signal from the transmit antenna to the PIM source and a PIM interference signal from the PIM source to the receive antenna. At the same time, a downlink transmission sequence x is constructed ₁ And x ₂ And obtaining a received signal r _n . Carrying out on-line training by using BP algorithm to estimate parameter h _k ,g _k ,f _nk And c _k Thereby obtaining interference channel information of the PIM.

By adopting the technical scheme, the network equipment can avoid exciting the passive intermodulation source through the descending airspace degree of freedom, and effectively restrain the passive intermodulation signal at the descending transmitting terminal, so that the generation of the passive intermodulation interference signal can be avoided, and the interference of the passive intermodulation signal on the ascending receiving signal can be eliminated, thereby effectively improving the performance of the communication system and improving the utilization rate of wireless resources.

In the embodiment of the present application, the method may also be applied to frequency domain scheduling of downlink users. For example, the downlink user band may be divided into two subsets, namely a subset a and a subset B, which have a large impact and a small impact on the uplink user band. Based on the correlation between the information of the interference channel of the passive intermodulation and the downlink channel (from the base station to the user), the user with high correlation can be scheduled in the subset B (the influence on the uplink user is small), and the user with low correlation can be scheduled in the subset A (the influence on the uplink user is large), so that the interference of the passive intermodulation signal caused by the signal sent by the downlink user on the uplink user can be reduced.

Referring to fig. 8, a schematic structural diagram of a communication device provided in an embodiment of the present application is shown, where the communication device 800 includes: a transceiver module 810 and a processing module 820. The communication device can be used for realizing the functions related to the network equipment in any one of the method embodiments. For example, the communication means may be a network device or a chip included in the network device.

When the communication apparatus is used as a network device to execute the method embodiment shown in fig. 3, the transceiver module 810 is configured to obtain interference channel information from multiple transmitting antennas to a passive intermodulation PIM source, and process a downlink signal according to the interference channel information; the processing module 820 is configured to send the processed downlink signal.

In one possible design, the processing module 820 is specifically configured to obtain the interference channel information from the multiple transmitting antennas to the PIM source by: generating a first scanning beam set, wherein the first scanning beam set comprises a plurality of scanning beams, and the dimensionality of each scanning beam is the number of transmitting antennas; scanning beams in the first scanning beam set are traversed to obtain an uplink PIM signal corresponding to each scanning beam; and determining interference channel information according to one or more scanning beams of which the corresponding uplink PIM signals in the first scanning beam set meet set conditions.

In a possible design, one or more scanning beams in the first scanning beam set, for which the corresponding uplink PIM signal meets the set condition, are the scanning beams with the largest received power of the corresponding uplink PIM signal in the first scanning beam set; the processing module 820 is specifically configured to determine interference channel information according to a scanning beam with the maximum receiving power of the uplink PIM signal corresponding to the first scanning beam set.

In a possible design, the channel matrix corresponding to the interference channel information is a conjugate of a scanning beam with the maximum received power of the corresponding uplink PIM signal in the first scanning beam set.

In a possible design, one or more scanning beams in the first scanning beam set, for which the corresponding uplink PIM signal meets the set condition, are the first S scanning beams in the first scanning beam set, where the received power of the corresponding uplink PIM signal is the largest, and S is a positive integer; the processing module 820 is specifically configured to determine the interference channel information according to the first S scanning beams in the first scanning beam set, where the received power of the corresponding uplink PIM signal is maximum.

In a possible design, the channel matrix corresponding to the interference channel information is a conjugate of the first S scanning beams in the first scanning beam set, where the received power of the corresponding uplink PIM signal is maximum, or a conjugate of one or more eigenvectors of a correlation matrix of the first S scanning beams in the first scanning beam set, where the received power of the corresponding uplink PIM signal is maximum.

In one possible design, the processing module 820 is specifically configured to generate the first set of scanning beams by: generating a second scanning beam set, and traversing the scanning beams in the second scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; taking the second scanning beam set as an input scanning beam set of the 1 st iteration, and executing the following iterative process: in the ith iteration, selecting a scanning beam with the maximum receiving power of an uplink PIM signal corresponding to the input scanning beam set as a first scanning beam; performing orthogonalization processing on an input scanning beam set based on the first scanning beam to obtain an output scanning beam set in the ith iteration, wherein the output scanning beam set comprises scanning beams which are formed by orthogonalizing each scanning beam except the first scanning beam in the input scanning beam set with the first scanning beam; traversing the scanning beams in the output scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; if the receiving power of the uplink PIM signal corresponding to each scanning beam in the output scanning beam set meets the convergence condition or the iteration frequency reaches a first set threshold value, ending the iteration, and forming a first scanning beam selected in each iteration process into a first scanning beam set; otherwise, entering the next iteration, and taking the output scanning beam set as the input scanning beam set in the next iteration.

In one possible design, the processing module 820 is specifically configured to generate the first set of scanning beams by: generating a second scanning beam set, wherein the second scanning beam set comprises P scanning beams; taking the second scanning beam set as the input scanning beam set of the 1 st iteration, and executing the following iteration process: in the ith iteration, aiming at each scanning beam in an input scanning beam set, adding the scanning beam and each offset vector in a preset offset vector set respectively to obtain an output scanning beam set in the ith iteration; traversing each scanning beam in the output scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; if the first Q receiving powers with the maximum receiving power of the uplink PIM signals corresponding to the scanning beams in the output scanning beam set tend to converge or the current iteration times reach a second set threshold value, ending the iteration, and forming the first P scanning beams with the maximum receiving power of the uplink PIM signals corresponding to the output scanning beam set into a first scanning beam set; otherwise, entering next iteration, and taking the first P scanning beams with the maximum receiving power of the corresponding uplink PIM signals in the output scanning beam set as the input scanning beam set in the next iteration.

In one possible design, the processing module 820 is specifically configured to generate the first set of scanning beams by: obtaining downlink channel coefficients from a plurality of transmitting antennas to a PIM source according to a channel free space loss model or an antenna electromagnetic field model; and generating a first scanning beam set according to the downlink channel coefficient.

In one possible design, the processing module 820 is specifically configured to obtain the interference channel information from multiple transmitting antennas to the PIM source by: constructing a signal model of a plurality of transmitting antennae to a PIM source and a PIM source to a plurality of receiving antennae; transmitting a plurality of groups of known signals at a plurality of transmitting antennas, and receiving uplink PIM signals respectively corresponding to each group of known signals in the plurality of groups of known signals at a plurality of receiving antennas; performing neural network training on the signal model according to the multiple groups of known signals and the uplink PIM signals corresponding to each group of known signals; and determining interference channel information according to the signal model obtained by training.

In one possible design, the processing module 820 is specifically configured to generate a precoding matrix according to the interference channel information; and precoding the downlink signal by using the precoding matrix.

In a possible design, the processing module 820 is specifically configured to calculate a null space of a channel matrix corresponding to the interference channel information, construct a null space matrix, project an initial precoding matrix to the null space matrix, and generate a new precoding matrix; or, the PIM source is regarded as a virtual user in the MIMO system, and a precoding matrix is generated according to the interference channel information.

In a possible design, the processing module 820 is specifically configured to perform precoding processing on the downlink signal; and calculating a null space of a channel matrix corresponding to the interference channel information, constructing a null space matrix, and projecting the downlink signal after precoding processing to the null space matrix to obtain a processed downlink signal.

It is to be understood that the processing module 820 involved in the communication device may be implemented by a processor or processor-related circuit components, and the transceiver module 810 may be implemented by a transceiver or transceiver-related circuit components. The operations and/or functions of the modules in the communication apparatus are respectively for implementing the corresponding flows of the method shown in fig. 3, and are not described herein again for brevity.

Please refer to fig. 9, which is a schematic structural diagram of a communication device according to an embodiment of the present application. The communication device may be embodied as a network device, such as a base station, for implementing the functions related to the network device in any of the above method embodiments.

The network device includes: one or more radio frequency units, such as a Remote Radio Unit (RRU) 901 and one or more baseband units (BBUs) (which may also be referred to as digital units, DUs) 902. The RRU 901 may be referred to as a transceiver unit, transceiver circuit, or transceiver, and may include at least one antenna 9011 and a radio frequency unit 9012. The RRU 901 is mainly used for receiving and transmitting radio frequency signals and converting radio frequency signals and baseband signals. The BBU 902 part is mainly used for performing baseband processing, controlling a base station, and the like. The RRU 901 and the BBU 902 may be physically disposed together, or may be physically disposed separately, that is, a distributed base station.

The BBU 902 is a control center of a base station, and may also be referred to as a processing unit, and is mainly used for performing baseband processing functions, such as channel coding, multiplexing, modulation, spreading, and the like. For example, the BBU (processing unit) 902 may be used to control the base station to execute the operation flow related to the network device in the above method embodiment.

In an example, the BBU 902 may be formed by one or more boards, and the boards may jointly support a radio access network (e.g., an LTE network) with a single access indication, or may respectively support radio access networks (e.g., LTE networks, 5G networks, or other networks) with different access schemes. The BBU 902 may further include a memory 9021 and a processor 9022, where the memory 9021 is configured to store necessary instructions and data. The processor 9022 is configured to control the base station to perform necessary actions, for example, to control the base station to perform the sending operation in the above method embodiment. The memory 9021 and the processor 9022 may serve one or more boards. That is, the memory and processor may be provided separately on each board. Multiple boards may share the same memory and processor. In addition, each single board can be provided with necessary circuits.

An embodiment of the present application further provides a chip system, including: a processor coupled to a memory for storing a program or instructions that, when executed by the processor, cause the system-on-chip to implement the method of any of the above method embodiments.

Optionally, the system on a chip may have one or more processors. The processor may be implemented by hardware or by software. When implemented in hardware, the processor may be a logic circuit, an integrated circuit, or the like. When implemented in software, the processor may be a general-purpose processor implemented by reading software code stored in a memory.

Optionally, the memory in the system-on-chip may also be one or more. The memory may be integrated with the processor or may be separate from the processor, which is not limited in this application. For example, the memory may be a non-transitory processor, such as a read only memory ROM, which may be integrated with the processor on the same chip or separately disposed on different chips, and the type of the memory and the arrangement of the memory and the processor are not particularly limited in this application.

The chip system may be a Field Programmable Gate Array (FPGA), an Application Specific Integrated Circuit (ASIC), a system on chip (SoC), a Central Processor Unit (CPU), a Network Processor (NP), a Digital Signal Processor (DSP), a Microcontroller (MCU), a Programmable Logic Device (PLD) or other integrated chips.

It will be appreciated that the steps of the above described method embodiments may be performed by logic circuits in a processor or instructions in the form of software. The steps of the method disclosed in connection with the embodiments of the present application may be directly implemented by a hardware processor, or may be implemented by a combination of hardware and software modules in a processor.

The embodiments of the present application further provide a computer-readable storage medium, where the computer-readable instructions are stored, and when the computer reads and executes the computer-readable instructions, the computer is caused to execute the method in any of the method embodiments.

The embodiments of the present application further provide a computer program product, which when read and executed by a computer, causes the computer to execute the method in any of the above method embodiments.

The embodiment of the application also provides a communication system, which comprises network equipment and at least one terminal equipment.

It should be understood that the processor referred to in the embodiments of the present application may be a CPU, but may also be other general purpose processors, DSPs, ASICs, FPGAs, or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

It will also be appreciated that the memory referred to in the embodiments of the application may be either volatile memory or nonvolatile memory, or may include both volatile and nonvolatile memory. The non-volatile memory may be a read-only memory (ROM), a Programmable ROM (PROM), an Erasable PROM (EPROM), an electrically Erasable EPROM (EEPROM), or a flash memory. Volatile memory can be Random Access Memory (RAM), which acts as external cache memory. By way of example, but not limitation, many forms of RAM are available, such as Static Random Access Memory (SRAM), dynamic Random Access Memory (DRAM), synchronous Dynamic Random Access Memory (SDRAM), double data rate SDRAM, enhanced SDRAM, SLDRAM, synchronous Link DRAM (SLDRAM), and direct rambus RAM (DR RAM).

It should be noted that when the processor is a general-purpose processor, a DSP, an ASIC, an FPGA or other programmable logic device, a discrete gate or transistor logic device, or a discrete hardware component, the memory (memory module) is integrated in the processor.

It should be noted that the memory described herein is intended to comprise, without being limited to, these and any other suitable types of memory.

It should be understood that the various numbers referred to in the various embodiments of the present application are merely for convenience of description and differentiation, and the serial numbers of the above-mentioned processes do not imply any order of execution, and the order of execution of the processes should be determined by their function and inherent logic, and should not constitute any limitation on the implementation of the embodiments of the present invention. S

Those of ordinary skill in the art will appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software depends upon the particular application and design constraints imposed on the technical solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the present application.

It can be clearly understood by those skilled in the art that, for convenience and simplicity of description, the specific working processes of the above-described systems, apparatuses and units may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the several embodiments provided in the present application, it should be understood that the disclosed system, apparatus and method may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units is only one logical division, and other divisions may be realized in practice, for example, a plurality of units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form.

The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment.

In addition, functional units in the embodiments of the present application may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The functions, if implemented in the form of software functional units and sold or used as a stand-alone product, may be stored in a computer readable storage medium. Based on such understanding, the technical solution of the present application or portions thereof that substantially contribute to the prior art may be embodied in the form of a software product stored in a storage medium and including instructions for causing a computer device (which may be a personal computer, a server, or a network device) to execute all or part of the steps of the method according to the embodiments of the present application. And the aforementioned storage medium includes: u disk, removable hard disk, read only memory, random access memory, magnetic disk or optical disk, etc. for storing program codes.

The above description is only for the specific embodiments of the present application, but the scope of the present application is not limited thereto, and any person skilled in the art can easily conceive of the changes or substitutions within the technical scope of the present application, and shall be covered by the scope of the present application. Therefore, the protection scope of the present application shall be subject to the protection scope of the claims.

Claims

1. A method of communication, the method comprising:

obtaining interference channel information from a plurality of transmitting antennas to a passive intermodulation PIM source;

processing the downlink signal according to the interference channel information;

sending the processed downlink signal;

the acquiring interference channel information from a plurality of transmitting antennas to a PIM source comprises: generating a first scanning beam set, wherein the first scanning beam set comprises a plurality of scanning beams, and the dimensionality of each scanning beam is the number of the transmitting antennas; traversing the scanning beams in the first scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam; determining the interference channel information according to one or more scanning beams of which the corresponding uplink PIM signals in the first scanning beam set meet set conditions;

or, the obtaining interference channel information from multiple transmitting antennas to the PIM source includes: constructing a signal model of the plurality of transmit antennas to the PIM source and the PIM source to a plurality of receive antennas; transmitting a plurality of groups of known signals at the plurality of transmitting antennas, and receiving uplink PIM signals respectively corresponding to each group of known signals in the plurality of groups of known signals at the plurality of receiving antennas; performing neural network training on the signal model according to the multiple groups of known signals and the uplink PIM signals corresponding to each group of known signals; and determining the interference channel information according to the signal model obtained by training.

2. The method according to claim 1, wherein the one or more scanning beams in the first scanning beam set for which the corresponding uplink PIM signal meets a set condition are scanning beams in the first scanning beam set for which the received power of the corresponding uplink PIM signal is the maximum;

the determining the interference channel information includes:

and determining the interference channel information according to the scanning beam with the maximum receiving power of the corresponding uplink PIM signal in the first scanning beam set.

3. The method of claim 2, wherein the channel matrix corresponding to the interference channel information is a conjugate of a scanning beam with a maximum received power of the corresponding uplink PIM signal in the first set of scanning beams.

4. The method according to claim 1, wherein the one or more scanning beams in the first scanning beam set for which the corresponding uplink PIM signal meets the set condition are the first S scanning beams in the first scanning beam set for which the corresponding uplink PIM signal has the largest received power, and S is a positive integer;

the determining the interference channel information includes:

and determining the interference channel information according to the first S scanning beams with the maximum receiving power of the corresponding uplink PIM signals in the first scanning beam set.

5. The method according to claim 4, wherein the channel matrix corresponding to the interference channel information is a conjugate of the first S scanning beams with the largest received power of the corresponding uplink PIM signal in the first scanning beam set, or a conjugate of one or more eigenvectors of a correlation matrix of the first S scanning beams with the largest received power of the corresponding uplink PIM signal in the first scanning beam set.

6. The method of any of claims 1 to 5, wherein the generating a first set of scanning beams comprises:

generating a second scanning beam set, and traversing scanning beams in the second scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam;

taking the second scanning beam set as an input scanning beam set of the 1 st iteration, and executing the following iteration process:

in the ith iteration, selecting a scanning beam with the maximum receiving power of the uplink PIM signal corresponding to the input scanning beam set as a first scanning beam;

performing orthogonalization processing on the input scanning beam set based on the first scanning beam to obtain an output scanning beam set in the ith iteration, wherein the output scanning beam set comprises scanning beams after each scanning beam in the input scanning beam set except the first scanning beam is orthogonal to the first scanning beam;

traversing the scanning beams in the output scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam;

if the receiving power of the uplink PIM signal corresponding to each scanning beam in the output scanning beam set meets a convergence condition, or the iteration frequency reaches a first set threshold value, ending the iteration, and forming a first scanning beam selected in each iteration process into the first scanning beam set;

and if not, entering next iteration, and taking the output scanning beam set as an input scanning beam set in the next iteration.

7. The method of any of claims 1 to 5, wherein the generating a first set of scanning beams comprises:

generating a second scanning beam set, wherein the second scanning beam set comprises P scanning beams;

in the ith iteration, aiming at each scanning beam in the input scanning beam set, adding the scanning beam and each offset vector in a preset offset vector set respectively to obtain an output scanning beam set in the ith iteration;

traversing each scanning beam in the output scanning beam set to obtain an uplink PIM signal corresponding to each scanning beam;

if the first Q received powers with the maximum received power of the uplink PIM signals corresponding to the scanning beams in the output scanning beam set tend to converge, or the current iteration number reaches a second set threshold, ending the iteration, and forming the first P scanning beams with the maximum received power of the uplink PIM signals corresponding to the output scanning beam set into the first scanning beam set;

otherwise, entering next iteration, and taking the first P scanning beams with the maximum receiving power of the corresponding uplink PIM signals in the output scanning beam set as the input scanning beam set in the next iteration.

8. The method of any of claims 1 to 5, wherein the generating a first set of scanning beams comprises:

obtaining downlink channel coefficients from the plurality of transmitting antennas to the PIM source according to a channel free space loss model or an antenna electromagnetic field model;

and generating the first scanning beam set according to the downlink channel coefficient.

9. The method of claim 1, wherein the processing the downlink signal according to the interference channel information comprises:

generating a precoding matrix according to the interference channel information;

and precoding the downlink signal by using the precoding matrix.

10. The method of claim 9, wherein the generating a precoding matrix according to the interfering channel information comprises:

calculating a null space of a channel matrix corresponding to the interference channel information, constructing a null space matrix, projecting an initial precoding matrix to the null space matrix, and generating a new precoding matrix; alternatively, the first and second electrodes may be,

and the PIM source is regarded as a virtual user in the MIMO system, and a precoding matrix is generated according to the interference channel information.

11. The method of claim 1, wherein the processing the downlink signal according to the interference channel information comprises:

precoding the downlink signal;

and calculating a null space of a channel matrix corresponding to the interference channel information, constructing a null space matrix, and projecting the downlink signal after precoding processing to the null space matrix to obtain the processed downlink signal.

12. A communication apparatus, characterized in that the apparatus comprises means for performing the method according to any of claims 1 to 11.

13. An apparatus for communication, the apparatus comprising at least one processor coupled with at least one memory:

the at least one processor configured to execute computer programs or instructions stored in the at least one memory to cause the apparatus to perform the method of any of claims 1-11.

14. A computer-readable storage medium storing instructions that, when executed, implement the method of any one of claims 1 to 11.