CN109831823B

CN109831823B - Method for communication, terminal equipment and network equipment

Info

Publication number: CN109831823B
Application number: CN201711182970.8A
Authority: CN
Inventors: 王文剑; 李知航; 孙欢
Original assignee: Nokia Shanghai Bell Co Ltd; Nokia Networks Oy
Current assignee: Nokia Shanghai Bell Co Ltd; Nokia Oyj
Priority date: 2017-11-23
Filing date: 2017-11-23
Publication date: 2021-01-12
Anticipated expiration: 2037-11-23
Also published as: CN109831823A; WO2019101173A1

Abstract

The embodiment of the disclosure relates to a method for communication, a terminal device and a network device. The method at the terminal device comprises: determining information of an interfering cell based on measurements of downlink reference signals; transmitting reference information to a network device of a serving cell of a terminal device, the reference information including an uplink reference signal precoded with a predetermined analog beam vector or beam matrix, information of the predetermined analog beam vector or beam matrix, and information of an interfering cell; receiving an optimized simulated beam vector or beam matrix from a network device; and determining a hybrid beam vector or a beam matrix based on the optimized simulated beam vector or the beam matrix. The method at a network device includes: receiving reference information; determining an optimized simulated beam vector or a beam matrix based on the reference information; and transmitting the optimized analog beam vector or the beam matrix to the terminal equipment. Thereby achieving a reduction in inter-cell interference and an improvement in overall network performance.

Description

Method for communication, terminal equipment and network equipment

Technical Field

Embodiments of the present disclosure relate to the field of wireless communications, and more particularly, to a method, a terminal device, and a network device for communication.

Background

Currently, the use of Unmanned Aerial Vehicles (UAVs) is becoming more common. Long Term Evolution (LTE) networks are expected to support UAVs. However, the introduction of User Equipment (UE) such as UAVs may face some new challenges for LTE networks. One of the challenges is strong inter-cell interference. Since the high altitude environment where the UAV UE is located can cause significant inter-cell interference, introducing the UAV UE in the current LTE network can significantly degrade the performance of the LTE network. Therefore, there is a need for an improved scheme to reduce such inter-cell interference to ensure the performance of LTE networks.

Disclosure of Invention

In general, embodiments of the present disclosure provide methods, terminal devices, and network devices implemented at the terminal devices and the network devices for communication.

In one aspect of the disclosure, a method implemented in a terminal device for communication is provided. The method comprises the following steps: determining information about an interfering cell based on measurements for downlink reference signals; sending reference information to a network device of a serving cell of the terminal device, wherein the reference information includes: an uplink reference signal precoded with a predetermined analog beam vector or beam matrix, information about said predetermined analog beam vector or beam matrix, and said information about interfering cells; receiving an optimized simulated beam vector or beam matrix from the network device, the optimized simulated beam vector or beam matrix determined by the network device based on the reference information; and determining a hybrid beam vector or a beam matrix for data transmission based on the optimized simulated beam vector or beam matrix.

In another aspect of the disclosure, a method implemented in a network device for communication is provided. The method can comprise the following steps: receiving reference information from a terminal device within a serving cell of the network device, the reference information including an uplink reference signal precoded with the predetermined analog beam vector or beam matrix, information about the predetermined analog beam vector or beam matrix, and information about an interfering cell; determining an optimized simulated beam vector or a beam matrix based on the reference information; and sending the optimized simulated beam vector or beam matrix to the terminal device so as to determine a mixed beam vector or beam matrix for data transmission.

In yet another aspect of the present disclosure, a terminal device is provided. The terminal device includes: a processor; and a memory coupled with the processor, the memory having instructions stored therein that, when executed by the processor, cause the electronic device to perform acts comprising: determining information about an interfering cell based on measurements for downlink reference signals; sending reference information to a network device of a serving cell of the terminal device, wherein the reference information includes: an uplink reference signal precoded with a predetermined analog beam vector or beam matrix, information about said predetermined analog beam vector or beam matrix, and said information about interfering cells; receiving an optimized simulated beam vector or beam matrix from the network device, the optimized simulated beam vector or beam matrix determined by the network device based on the reference information; and determining a hybrid beam vector or a beam matrix for data transmission based on the optimized simulated beam vector or beam matrix.

In yet another aspect of the present disclosure, a network device is provided. The network device includes: a processor; and a memory coupled with the processor, the memory having instructions stored therein that, when executed by the processor, cause the electronic device to perform acts comprising: receiving reference information from a terminal device within a serving cell of the network device, the reference information including an uplink reference signal precoded with the predetermined analog beam vector or beam matrix, information about the predetermined analog beam vector or beam matrix, and information about an interfering cell; determining an optimized simulated beam vector or a beam matrix based on the reference information; and sending the optimized simulated beam vector or beam matrix to the terminal device so as to determine a mixed beam vector or beam matrix for data transmission.

In yet another aspect of the disclosure, a computer-readable storage medium is provided. The medium comprises machine executable instructions which, when executed by a device, cause the device to perform the above-described method for communication implemented at a terminal device.

In yet another aspect of the disclosure, a computer-readable storage medium is provided. The medium includes machine executable instructions that, when executed by a device, cause the device to perform the above-described method for communication implemented at a network device.

According to the scheme of the embodiment of the disclosure, the reduction of inter-cell interference and the improvement of the whole LTE network performance can be realized with low complexity.

It should be understood that the statements herein reciting aspects are not intended to limit the critical or essential features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become apparent from the following description.

Drawings

The above and other features, advantages and aspects of various embodiments of the present disclosure will become more apparent by referring to the following detailed description when taken in conjunction with the accompanying drawings. In the drawings, like or similar reference characters designate like or similar elements, and wherein:

FIG. 1 illustrates a schematic diagram of an exemplary communication scenario in which embodiments of the present disclosure may be implemented;

fig. 2 is a flow chart illustrating a method for communication implemented at a terminal device in accordance with an embodiment of the present disclosure;

fig. 3 is a block diagram illustrating a specific implementation example of a hybrid receive beamforming mechanism at a terminal device according to an embodiment of the present disclosure;

fig. 4 is a flow chart illustrating a method for communication implemented at a network device in accordance with an embodiment of the present disclosure;

fig. 5 is a flow diagram illustrating a method at a network device for determining an optimized simulated beam vector or beam matrix in accordance with an embodiment of the present disclosure; and

FIG. 6 illustrates a simplified block diagram of an electronic device suitable for implementing embodiments of the present disclosure.

Detailed Description

Embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. While certain embodiments of the present disclosure have been illustrated in the accompanying drawings, it is to be understood that the present disclosure may be embodied in various forms and should not be construed as limited to the embodiments set forth herein, but rather are provided for a more thorough and complete understanding of the present disclosure. It should be understood that the drawings and embodiments of the disclosure are for illustration purposes only and are not intended to limit the scope of the disclosure.

The term "network device" as used herein refers to a base station or other entity or node having a particular function in a communication network. A "base station" may represent a node B (NodeB or NB), an evolved node B (eNodeB or eNB), a Remote Radio Unit (RRU), a Radio Head (RH), a Remote Radio Head (RRH), a relay, or a low power node such as a pico base station, a femto base station, or the like. In the context of the present disclosure, the terms "network device" and "base station" may be used interchangeably for ease of discussion purposes, and refer primarily to an eNB as an example of a network device.

The term "terminal device" as used herein refers to any terminal device or User Equipment (UE) capable of wireless communication with a base station or with each other. In particular, a terminal device herein may refer to a terminal device causing strong inter-cell interference, such as a terminal device operating aloft, such as a UAV. However, as an example, the terminal device may include a sensor having a communication function, a detector, a Mobile Terminal (MT), a Subscriber Station (SS), a Portable Subscriber Station (PSS), a Mobile Station (MS), or an Access Terminal (AT), and the above-described devices in a vehicle, and the like. In the context of the present disclosure, the terms "terminal device" and "user device" may be used interchangeably for purposes of discussion convenience, and primarily with UAVs as examples of terminal devices.

The terms "include" and variations thereof as used herein are inclusive and open-ended, i.e., "including but not limited to. The term "based on" is "based, at least in part, on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment". Relevant definitions for other terms will be given in the following description.

In order to reduce the above strong inter-cell interference, a full-dimensional multiple-input multiple-output (FD-MIMO) mechanism on the network equipment (e.g. eNB) side has been proposed, which reduces inter-cell interference in advance by a transmit beamforming mechanism. This FD-MIMO mechanism at the network device side can concentrate the transmit power and avoid inter-cell interference for downlink data channel transmission in advance. However, it does not address inter-cell interference for downlink control channel transmissions, since it still uses a non-beamforming transmission scheme for downlink control channel transmissions in order to facilitate fast random access of users to the network.

In this case, a receive beamforming mechanism on the terminal device side is considered to improve the performance of the downlink control channel and the data channel at the same time. The receive beamforming mechanism has been studied in the related art of the fifth generation mobile communication (5G) New Radio (NR). However, the original purpose of these mechanisms is to enhance the quality of the service link, rather than to eliminate or reduce inter-cell interference, and thus are not suitable for LTE communications for terminal devices such as UAVs. Furthermore, these mechanisms are too complex and require too much time for receive beam design. Also, these mechanisms can only be adapted to 5G NR new interfaces and 5G NR terminal devices.

In view of this, one of the concepts of the embodiments of the present disclosure is that: a unique receive beamforming mechanism is provided to eliminate or reduce inter-cell interference to support LTE communications for good performance terminal devices such as UAVs while maintaining low latency, low complexity, and low cost. This is described in detail below with reference to the drawings.

Fig. 1 illustrates a schematic diagram of an exemplary communication scenario 100 in which embodiments of the present disclosure may be implemented. For ease of discussion, the following may use an eNB as an example of a network device or base station and a UAV as an example of a terminal device. It should be understood, however, that this is done merely for convenience in explaining the concepts of the embodiments of the present disclosure and is not intended to limit the application scenarios or scope of the present disclosure in any way.

As shown in fig. 1, a terminal device 110, such as a UAV, is, for example, within a serving cell of a network device 120, such as an eNB. In downlink transmissions, terminal device 110 is subject to strong interference, i.e., inter-cell interference, from other network devices (e.g., network device 130 such as an eNB). Only one terminal device 110 and two

network devices

120 and 130 are shown in the figure, but it should be understood that there may be multiple terminal devices, such as UAVs, per serving cell and that there may be inter-cell interference from multiple network devices (i.e., multiple interfering cells) per terminal device. This is not to be taken in any way limiting by the present application.

The disclosed embodiments aim to provide a receive beamforming mechanism at the terminal device 110 side to simultaneously improve the performance of both downlink control channels and data channels in LTE communications for terminal devices such as UAVs, thereby improving the utilization of system resources. The inventors have observed that by placing more antennas at terminal device 110, more spatial degrees of freedom can be used to cancel or reduce inter-cell interference. In this case, the terminal device 110 needs to have more antenna ports. If the antenna ports are increased, it becomes more complicated to acquire beams per subcarrier for the case where digital beams are implemented per resource block or per subcarrier. Specifically, increasing antenna ports would require terminal device 110 to estimate the high-dimensional channel matrix in a short period of time. Furthermore, adding antenna ports increases the hardware cost and processing complexity of terminal device 110, as each antenna port needs to be controlled through a separate Radio Frequency (RF) link. In view of this, the inventors propose to implement a hybrid beamforming mechanism at a terminal device 110, such as a UAV, in order to improve the system performance while keeping the number of antenna ports constant, thereby ensuring low latency, low complexity and low cost.

To this end, the disclosed embodiments provide a method and corresponding devices for communication implemented at a terminal device and a network device. As described in detail below in conjunction with fig. 2-6.

Fig. 2 shows a flow diagram of a method 200 for communication implemented at a terminal device in accordance with an embodiment of the present disclosure. The method 200 may be implemented, for example, at a terminal device (such as a UAV)110 of fig. 1. For ease of description, the method 200 will be described below in conjunction with the environment of FIG. 1. However, it should be understood that the method may be implemented at any terminal device, particularly a terminal device such as a UAV.

As mentioned previously, in downlink transmissions, terminal device 110 may experience strong interference from one or more interfering cells (such as network device 130). According to embodiments of the present disclosure, terminal device 110 may collect information about interfering cells to facilitate cancellation or reduction of interference. According to an embodiment of the present disclosure, as shown in fig. 2, at 210, terminal device 110 may determine information about interfering cells based on measurements for downlink reference signals. As is known, terminal device 110 may receive downlink reference signals transmitted by network devices of various cells. In embodiments of the present disclosure, the downlink reference signal may be, for example, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), or other downlink reference signal.

According to embodiments of the present disclosure, terminal device 110 may determine information about interfering cells based on respective Reference Signal Received Powers (RSRPs) of downlink reference signals from a serving cell (e.g., network device 120 of fig. 1) and at least one other cell (e.g., network device 130 of fig. 1). In one embodiment, a set of interfering cells may be determined as information about the interfering cells based on a comparison between downlink reference signals from the serving cell and downlink reference signals from other cells. For example, the information about the interfering cells may be represented by a set { n }, where the set { n } may be determined by the following equation (1):

{n,||RSPR_n-RSRP₁|≤κ} (1)

wherein n represents the identity of the interfering cell, RSPR_nRSRP, RSPR representing downlink reference signals for interfering cells₁RSRP, which represents the downlink reference signal for the serving cell, k represents a predetermined threshold. It should be appreciated that the determination of information about interfering cells is not limited to the manner listed above, but may be implemented in any suitable manner known in the art or developed in the future.

Then, at 220, the terminal device 110 may send the reference information to the network device 120 of the serving cell in which it is located. The reference information includes an uplink reference signal precoded with a predetermined analog beam vector or beam matrix, information about the predetermined analog beam vector or beam matrix, and information about the interfering cell.

According to an embodiment of the present disclosure, terminal device 110 may select a predetermined analog beam vector or beam matrix from a predetermined codebook based on downlink measurements of the serving cell. The predetermined codebook is known to both the terminal device and the network device serving the cell. For example, terminal device 110 may select an analog beam vector or beam matrix that maximizes the quality of the serving link from a predetermined codebook as the predetermined analog beam vector or beam matrix based on downlink measurements for the network device of the serving cell (e.g., network device 120 of fig. 1). For example, the predetermined analog beam vector or beam matrix may be represented by W, which may be determined by the following equation (2):

wherein K_fDenotes the number of sub-carriers, K_cRepresenting code words C within a predetermined codebook_iNumber of (2), H_1,1(f) A channel matrix representing a network device (index 1) to a terminal device (index 1) of a serving cell; f denotes an index of a subcarrier or a resource block. It should be appreciated that the selection of the predetermined analog beam vector or beam matrix may be implemented in any suitable manner known in the art or developed in the future and is not limited to the above listed manners.

According to an embodiment of the present disclosure, the terminal device 110 may transmit an uplink reference signal using the selected predetermined analog beam vector or beam matrix W. For example, the uplink reference signal is precoded and transmitted using the selected predetermined analog beam vector or beam matrix W.

In accordance with an embodiment of the present disclosure, terminal device 110 also transmits information about the predetermined analog beam vector or beam matrix to a network device of the serving cell (e.g., network device 120 of fig. 1) along with information about the interfering cell { i } as determined at 210 above. In one embodiment, the information about the predetermined analog beam vector or beam matrix may comprise, for example, an index of the predetermined analog beam vector or beam matrix W within a predetermined codebook. Of course, the information may also include other information related to the predetermined analog beam vector or beam matrix, which is not limited in any way by the present application.

At 230, terminal device 110 may receive an optimized analog beam vector or beam matrix from a network device of a serving cell (e.g., network device 120 of fig. 1). The optimized simulated beam vector or beam matrix is determined by the network device based on the reference information transmitted at 220. The determination of the optimized simulated beam vector or beam matrix allows for the elimination or reduction of inter-cell interference and improvement of the quality of the serving link. This will be described in detail later with reference to fig. 4 and 5.

At 240, terminal device 110 may determine a hybrid beam vector or beam matrix for data transmission based on the optimized simulated beam vector or beam matrix. According to an embodiment of the present disclosure, the terminal device 110 may generate a mixed beam vector or a beam matrix based on the optimized simulated beam vector or beam matrix in combination with a linear precoding scheme. In accordance with embodiments of the present disclosure, the linear precoding scheme may be a scheme based on a minimum mean-square error estimation (MMSE) criterion, a zero-forcing criterion, or any other suitable criterion known in the art or developed in the future. According to embodiments of the present disclosure, a hybrid beam vector or a beam matrix is generated per resource block or per subcarrier. In one embodiment, the mixed beam vector or beam matrix per resource block or per subcarrier may be represented by w (f), which is determined by the following equation (3):

W(f)＝W₁(f)A (3)

where f denotes the index of the resource block or subcarrier, A denotes the optimized analog beam vector or beam matrix received at 230, W₁(f) Representing a beam vector or beam matrix for linear precoding per resource block or subcarrier.

For example, assuming that each terminal device (e.g., terminal device 110 of fig. 1) has N antenna ports and each network device (e.g., network device 120 and network device 130 of fig. 1) has M antenna ports, the ith terminal device and the jth network deviceThe channel between the devices can be represented as H with N x M dimensions_i,j. In one embodiment, W may be designed based on MMSE criterion₁(f) As shown in the following formula (4):

where f denotes the index of the resource block or subcarrier, H_1,1(f) Channel matrix representing network device (index 1) to terminal device (index 1) of serving cell, K represents number of interfering cells, σ represents number of interfering cells₀ ²Representing the background noise power at the terminal device 1, I representing an identity matrix with dimension M;

representing a matrix pseudo-inverse operation.

In another embodiment, W may be designed based on zero-forcing criteria₁(f) As shown in the following formula (5):

wherein f represents the index of a resource block or a subcarrier, K represents the number of interfering cells, μ represents the rank of a desired data stream, and M is the number of antenna ports on the network equipment side;

expressing a matrix to perform pseudo-inverse operation; h_1,k(f) A channel matrix representing the interfering cell k to the terminal device 1; g_μ(f) Is a sub-matrix of the matrix G (f) and is composed of the first mu row vectors of G (f).

After determining the hybrid beam vector or the beam matrix, the terminal device 110 may use it for data transmission. For example, the hybrid beam vector or beam matrix may be used for reception or demodulation of downlink signals. For ease of understanding, a specific example of a hybrid receive beamforming mechanism according to an embodiment of the present disclosure is described below in conjunction with fig. 3.

Fig. 3 illustrates a specific implementation example 300 of a hybrid receive beamforming mechanism at a terminal device according to an embodiment of the present disclosure. This mechanism may be implemented, for example, at terminal device 110 of fig. 1.

As shown in fig. 3, an analog beamformer 310, an RF chain 320, and a digital beamformer 330 may be provided at terminal device 110. In an embodiment of the present disclosure, the analog beamformer 310 may be implemented by a phase shift circuit, as shown in fig. 3. In downlink transmission, analog beamforming is performed on a plurality of downlink data streams received through the antennas via the analog beamformer 310, wherein the processing may be performed using the optimized analog beam vector or beam matrix a described above, resulting in a reduced dimensionality of the corresponding data streams. The reduced-dimension data streams are then passed to a digital beamformer 330 via respective RF links 320 for digital beam processing resulting in a lower-dimension baseband output signal.

It will be appreciated that according to embodiments of the present disclosure, since an optimized analog beam vector or beam matrix considering inter-cell interference is utilized, the inter-cell interference can be eliminated or reduced, thereby ensuring system performance. In addition, the hybrid beam forming mechanism is utilized, so that the number of antenna interfaces at the terminal equipment is unchanged, and low time delay, low complexity and low cost are ensured.

In addition, the above-described hybrid beam vector or beam matrix may also be used for transmission of uplink signals. For example, it may be used for transmit power concentration in a desired direction, whereby terminal device transmit power leakage to other cells may be reduced, thereby reducing uplink interference. Further, the hybrid beamforming mechanism described above may flexibly use the antenna array of the terminal device for inter-cell interference without introducing additional baseband processing complexity.

A method for communication implemented at a terminal device for implementing a hybrid receive beamforming mechanism according to embodiments of the present disclosure has been described thus far. In correspondence with the above-described methods, the disclosed embodiments also provide methods for communication implemented at a network device for implementing a hybrid beamforming mechanism at a terminal device side, such as a UAV, in accordance with embodiments of the present disclosure. Fig. 4 shows a flow diagram of a method 400 for communication implemented at a network device in accordance with an embodiment of the present disclosure. For ease of description, the method 400 will be described below in conjunction with the environment of FIG. 1. However, the method 400 may be implemented at any network device, such as the network device 120 of fig. 1.

As shown in fig. 4, at 410, network device 120 may receive uplink reference signals from terminal devices 110 within its serving cell, information about a predetermined analog beam vector or beam matrix, and information about an interfering cell. Wherein the uplink reference signals are precoded with a predetermined analog beam vector or beam matrix. This step corresponds to the step described above in connection with block 220 of fig. 2. For the uplink reference signal, the information about the predetermined analog beam vector or beam matrix, and the information about the interfering cell, reference may be made to the description above in connection with block 220 of fig. 2, which is not repeated herein.

At 420, the network device 120 may determine an optimized simulated beam vector or beam matrix based on the uplink reference signal, the information about the predetermined simulated beam vector or beam matrix, and the information about the interfering cell, as mentioned above in connection with the description of block 230 of fig. 2. The determination of the optimized simulated beam vector or beam matrix is illustrated below in conjunction with fig. 5.

Fig. 5 is a flow diagram illustrating a method 500 at a network device for determining an optimized simulated beam vector or beam matrix in accordance with an embodiment of the disclosure. The method may be implemented at any network device, such as network device 120 of fig. 1.

As shown in fig. 5, at 510, network device 120 may obtain corresponding uplink measurement information for the serving cell and the interfering cell based on the uplink reference signal and the information about the interfering cell. According to an embodiment of the present disclosure, the network device 120 may measure the uplink channel for the uplink reference signal from the terminal device 110 within its serving cell, thereby obtaining uplink measurement information for the serving cell. On the other hand, according to embodiments of the present disclosure, network device 120 may obtain uplink measurement information for an interfering cell (such as network device 130 of fig. 1) from the interfering cell based on information about the interfering cell.

In one embodiment, the network device 120 may send a request to the interfering cell based on the information about the interfering cell. For example, network device 120 may send information about a target terminal device (e.g., terminal device 110) to network device 130 to obtain information of uplink channel measurements made by network device 130 for uplink reference signals of terminal device 110.

At 520, network device 120 may determine respective Channel State Information (CSI) for the serving cell and the interfering cell based on information about the predetermined analog beam vector or beam matrix and the uplink measurement information obtained at 510. According to an embodiment of the present disclosure, based on the information on the predetermined analog beam vector or beam matrix fed back by the terminal device 110, the network device 120 may determine the predetermined analog beam vector or beam matrix itself, e.g., the aforementioned W. Also, the uplink measurement information obtained at block 510 may be represented as

Thus, network device 120 may recover the entire CSI, e.g., the estimate matrix for the ith channel matrix, for the serving and interfering links

Channels that can be obtained by uplink measurements

And a predetermined analog beam vector or beam matrix W fed back by the terminal device, which can be determined by the following equation (6):

wherein

Representing a pseudo-inverse operation on the matrix;

representing a conjugate transpose operation of the matrix.

At 530, network device 120 may determine the optimized analog beam vector or beam matrix based on the recovered CSI. In accordance with embodiments of the present disclosure, network device 120 may design an optimized analog beam vector or beam matrix based on the recovered CSI information such that inter-cell interference is reduced or eliminated and service link quality is improved. In one embodiment, the optimized analog beam vector or beam matrix a may be designed, for example, according to the criterion of maximizing the signal leakage ratio as follows (7):

wherein, K_iIndicating the number of interfering cells, K, reported by the terminal equipment or determined by the network equipment of the serving cell_fDenotes the number of subcarriers, H_1,i(f) And the matrix represents a channel matrix between the terminal equipment and the 1 st cell, F represents the index of a subcarrier or a resource block, Q represents a vector or a matrix with the F norm of 1, and the rank of the matrix is determined by the number of streams for transmitting data. K_fRepresents the number of subcarriers or resource blocks; k_iIndicating the number of interfering cells, determined by the network equipment of the serving cell, K_iAnd N is less than or equal to N, wherein N is the number of the interference cells reported by the terminal equipment.

It should be understood that other criteria may be used to accomplish the design of the optimized simulated beam vector or beam matrix a, and the application is not limited thereto.

Returning to fig. 4, at 430 network device 120 transmits the optimized simulated beam vector or beam matrix to terminal device 110. As previously described in connection with block 240 of fig. 2, terminal device 110 may use the received optimized analog beam vector or beam matrix for determination of a hybrid beam vector or beam matrixFor use in data transmission. In accordance with embodiments of the present disclosure, network device 120 may derive a quantized version of the optimized analog beam vector or beam matrix a

And will be

To the terminal device 110. Alternatively, network device 120 may also be configured to communicate with other devices

Is sent to the terminal device 110. Of course, the application is not limited to these embodiments, but information about the optimized simulated beam vector or beam matrix may be conveyed in any other suitable way.

The method for communication implemented at a network device for implementing a hybrid receive beamforming mechanism according to the embodiment of the present disclosure has been described so far, which corresponds to the processing of the method for communication implemented at the terminal device side described in conjunction with fig. 2 to 3, and other processing details may refer to the description of fig. 2 to 3, which is not repeated herein.

In addition, the inventors performed a performance simulation analysis on this mechanism, as shown in table I below.

TABLE I

As can be seen from table I, the hybrid beamforming mechanism according to embodiments of the present disclosure may effectively support coexistence of LTE UAV terminal devices and LTE non-UAV terminal devices (terrestrial terminal devices), and overall system performance is improved.

According to example embodiments of the present disclosure, a hybrid beamforming mechanism on the terminal device side, such as a UAV, may be implemented, wherein reduction or elimination of inter-cell interference and improvement of overall system performance are considered, while maintaining low latency, low complexity and low cost. In the mechanism, the design of the simulated beam vector or the beam matrix is based on the channel quadratic statistic characteristics, so that the mechanism has stronger robustness on the UAV mobility and the return delay. Moreover, the number of target interfering cells can be dynamically changed according to the measurement and the backhaul delay, so that the method can be well adapted to the actual scene.

FIG. 6 illustrates a simplified block diagram of an electronic device 600 suitable for implementing embodiments of the present disclosure. Device 600 may be used to implement a terminal device (e.g., terminal device 110 of fig. 1) and/or to implement a network device (e.g., network device 120 of fig. 1).

As shown, the device 600 may include one or more processors 610, one or more memories 620 coupled to the processors 610, and one or more transmitters and/or receivers (TX/RX)640 coupled to the processors 610.

The processor 610 may be of any suitable type suitable to the local technical environment and may include, but is not limited to, one or more of general purpose computers, special purpose computers, microcontrollers, digital signal controllers (DSPs), and processors based on a multi-core processor architecture. Device 600 may have multiple processors, such as application specific integrated circuit chips that are time slaved to a clock synchronized to the main processor.

The memory 620 may be of any suitable type suitable to the local technical environment and may be implemented using any suitable data storage technology, such as non-transitory computer-readable storage media, semiconductor-based memory devices, magnetic memory devices and systems, optical memory devices and systems, fixed memory and removable memory, as non-limiting examples.

Memory 620 stores at least a portion of program 630. TX/RX 640 is used for bi-directional communication. TX/RX 640 has at least one antenna to facilitate communication, but in practice the device may have several antennas. The communication interface may represent any interface required for communication with other network elements.

The programs 630 may include program instructions that, when executed by the associated processor 610, enable the device 600 to operate in accordance with embodiments of the disclosure, as described with reference to fig. 2-5. That is, embodiments of the present disclosure may be implemented by computer software executable by the processor 610 of the device 600, or by hardware, or by a combination of software and hardware.

In general, the various example embodiments of this disclosure may be implemented in hardware or special purpose circuits, software, logic or any combination thereof. Certain aspects may be implemented in hardware, while other aspects may be implemented in firmware or software which may be executed by a controller, microprocessor or other computing device. While aspects of embodiments of the disclosure have been illustrated or described as block diagrams, flow charts, or using some other pictorial representation, it is well understood that the blocks, apparatus, systems, techniques or methods described herein may be implemented in, as non-limiting examples, hardware, software, firmware, special purpose circuits or logic, general purpose hardware or controller or other computing devices, or some combination thereof. Examples of hardware devices that may be used to implement embodiments of the present disclosure include, but are not limited to: field Programmable Gate Arrays (FPGAs), Application Specific Integrated Circuits (ASICs), Application Specific Standard Products (ASSPs), systems on a chip (SOCs), Complex Programmable Logic Devices (CPLDs), and the like.

By way of example, embodiments of the disclosure may be described in the context of machine-executable instructions, such as those included in program modules, being executed in a device on a target real or virtual processor. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of the program modules may be combined or divided between program modules as described. Machine-executable instructions for program modules may be executed within local or distributed devices. In a distributed facility, program modules may be located in both local and remote memory storage media.

Computer program code for implementing the methods of the present disclosure may be written in one or more programming languages. These computer program codes may be provided to a processor of a general purpose computer, special purpose computer, or other programmable data processing apparatus, such that the program codes, when executed by the computer or other programmable data processing apparatus, cause the functions/acts specified in the flowchart and/or block diagram block or blocks to be performed. The program code may execute entirely on the computer, partly on the computer, as a stand-alone software package, partly on the computer and partly on a remote computer or entirely on the remote computer or server.

In the context of this disclosure, a machine-readable medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium may be a machine-readable signal medium or a machine-readable storage medium. A machine-readable medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or any suitable combination thereof. More detailed examples of a machine-readable storage medium include an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical storage device, a magnetic storage device, or any suitable combination thereof.

Additionally, while operations are depicted in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. In some cases, multitasking or parallel processing may be beneficial. Likewise, while the above discussion contains certain specific implementation details, this should not be construed as limiting the scope of any invention or claims, but rather as describing particular embodiments that may be directed to particular inventions. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable subcombination.

Although the subject matter has been described in language specific to structural features and/or methodological acts, it is to be understood that the subject matter defined in the appended claims is not limited to the specific features or acts described above. Rather, the specific features and acts described above are disclosed as example forms of implementing the claims.

Claims

1. A method implemented at a terminal device for communication, comprising:

determining information about an interfering cell based on measurements for downlink reference signals;

sending reference information to a network device of a serving cell of the terminal device, wherein the reference information includes: an uplink reference signal precoded with a predetermined analog beam vector or beam matrix, information about said predetermined analog beam vector or beam matrix, and said information about interfering cells;

receiving an optimized simulated beam vector or beam matrix from the network device, the optimized simulated beam vector or beam matrix determined by the network device based on the reference information; and

determining a hybrid beam vector or a beam matrix for data transmission based on the optimized simulated beam vector or beam matrix.

2. The method of claim 1, wherein determining the information about the interfering cell comprises:

determining respective Reference Signal Received Powers (RSRPs) of the downlink reference signals from the serving cell and at least one other cell; and

determining a set of interfering cells based on the RSRP of the downlink reference signals.

3. The method of claim 1, further comprising:

selecting the predetermined analog beam vector or beam matrix from a predetermined codebook based on measurements of the downlink reference signal for the serving cell.

4. The method of claim 1, wherein determining the mixed beam vector or beam matrix comprises:

generating the hybrid beam vector or beam matrix based on the optimized simulated beam vector or beam matrix in combination with a linear precoding scheme.

5. The method of claim 1, wherein the terminal device is an Unmanned Aerial Vehicle (UAV).

6. A method implemented at a network device for communication, comprising:

receiving reference information from a terminal device within a serving cell of the network device, the reference information including an uplink reference signal precoded with a predetermined analog beam vector or beam matrix, information about the predetermined analog beam vector or beam matrix, and information about an interfering cell;

determining an optimized simulated beam vector or a beam matrix based on the reference information; and

and sending the optimized simulated beam vector or the optimized simulated beam matrix to the terminal equipment so as to determine a mixed beam vector or a beam matrix for data transmission.

7. The method of claim 6, wherein determining the optimized simulated beam vector or beam matrix comprises:

obtaining respective uplink measurement information for a serving cell and an interfering cell based on the uplink reference signal and the information on the interfering cell;

determining respective Channel State Information (CSI) for the serving cell and the interfering cell based on the information on the predetermined analog beam vector or beam matrix and the uplink measurement information; and

determining the optimized simulated beam vector or beam matrix based on the CSI.

8. The method of claim 7, wherein obtaining the uplink measurement information comprises:

measuring an uplink channel for the serving cell for the uplink reference signal; and

obtaining uplink measurement information for the interfering cell from the interfering cell based on the information on the interfering cell.

9. The method of claim 6, wherein the terminal device is an Unmanned Aerial Vehicle (UAV).

10. A terminal device, comprising:

a processor; and

a memory coupled with the processor, the memory having instructions stored therein that, when executed by the processor, cause the apparatus to perform acts comprising:

11. The apparatus of claim 10, wherein determining the information about the interfering cell comprises:

12. The apparatus of claim 10, wherein the actions further comprise:

13. The apparatus of claim 10, wherein determining the mixed beam vector or beam matrix comprises:

14. The apparatus of claim 10, wherein the terminal apparatus is an Unmanned Aerial Vehicle (UAV).

15. A network device, comprising:

a processor; and

16. The apparatus of claim 15, wherein determining the optimized simulated beam vector or beam matrix comprises:

17. The apparatus of claim 16, wherein obtaining the uplink measurement information comprises:

18. The apparatus of claim 15, wherein the terminal apparatus is an Unmanned Aerial Vehicle (UAV).

19. A computer-readable storage medium comprising machine-executable instructions that, when executed by a device, cause the device to perform the method of any one of claims 1-5.

20. A computer-readable storage medium comprising machine-executable instructions that, when executed by a device, cause the device to perform the method of any of claims 6-9.