WO2018095122A1 - Wireless communication method and wireless communication device - Google Patents

Abstract

Disclosed are a wireless communication method and a wireless communication device. The wireless communication device comprises a processing circuit. The processing circuit is configured to carry out first channel measurement according to a first reference signal from a target communication device, determine a plurality of weighting parameters based on a result of the first channel measurement, so that a synthesized channel obtained by carrying out weighted combination on a plurality of pre-set channel features by using the plurality of weighting parameters matches an actual channel, wherein the plurality of pre-set channel features are known by both the wireless communication device and the target communication device, and generate feedback information for indicating the plurality of weighting parameters to send the feedback information to the target communication device.

Description

Wireless communication method and wireless communication device Technical field

The present invention relates to a wireless communication method and a wireless communication device, and in particular to a method and apparatus for mixing channel state information feedback in a multi-antenna scenario.

Background technique

Currently, with the continuous evolution of the 3rd Generation Partnership Project (3GPP), an increasing number of antenna ports are employed to improve the overall performance of Long Term Evolution (LTE) systems. However, this also brings some challenges to the operation of the wireless communication system, including the process and overhead of acquiring channel state information (CSI).

In order to cope with the above problems, 3GPP is discussing the feedback mechanism and process of Hybrid Channel State Information (Hybrid CSI) in the Rel.14 version. The main purpose is to not only better support old users (legacy UEs) but also reduce the overhead of channel state information reference signals (CSI-RS) by performing beamforming or antenna port virtualization.

The feedback mechanism for mixing channel state information can be roughly described as the following two phases. In the first phase, the network side device (including the eNB or the base station) transmits a cell-specific CSI-RS including a beamformed CSI-RS (hereinafter referred to as beamforming CSI-RS) and Pre-coded CSI-RS for all ports. Next, the terminal device (for example, the user equipment UE) feeds back a CSI-RS indicator (CRI), or a partial precoding matrix indicator (partial PMI), or an analog beam pointing to the network side device by measuring the received CSI-RS. . The purpose of the first phase is to allow network-side devices to obtain long-term, coarse CSI for use in the second phase. In the second phase, the network side device transmits the beamformed user-specific (UE-Specific) CSI-RS according to the coarse CSI obtained in the first phase, and then the terminal device measures the received CSI-RS, And feeding back CSI to the network side device, such as a feedback rank indicator (RI) or a precoding matrix indicator (PMI) or a channel quality indicator (CQI).

Figure 1 shows the representation of the above mechanism in the time domain. Two cycles of acquiring mixed channel state information are schematically illustrated in FIG. 1, each cycle including a first phase and a second phase. In the first phase of the first acquisition cycle, the network side device transmits three cell-specific CSI-RSs, namely CSI-RS11, CSI-RS12 and CSI-RS13. Receiving from the terminal device After the feedback (not shown in the figure), the network side device transmits the NZP CSI-RS21 and the NZP CSI-RS22 for the first terminal device and the second terminal device at different times in the second phase, respectively, which are user-specific CSI-RS. The first and second terminal devices each generate CSI by measuring the received user-specific CSI-RS, and feed back the generated CSI to the network side device (not shown). In addition, in the second acquisition period, the operation of the network side device in the first phase is the same as the operation in the first phase of the first acquisition cycle, and then the NZP CSI for the third terminal device is transmitted in the second phase. RS23. Similarly, the third terminal device can determine the CSI by measuring the NZP CSI-RS 23 and feed it back to the network side device.

In the feedback process of the mixed channel state information as described above, since the terminal device feeds back a rough channel state information in the first stage, the mechanism also has an inaccurate beam pointing problem. Specifically, it can be divided into the following three situations for discussion.

In the first case, in the case where the terminal device feeds back a CSI-RS resource indicator (CRI) in the first phase, the network side device transmits a user-dedicated beamforming CSI-RS according to the CRI. For example, in the 3GPP Rel.13 version, the network side only supports 16 ports of CSI-RS. Assuming that there are 4 CSI-RS ports configured in the horizontal dimension, only 4 CSI-RS ports can be configured in the vertical dimension. In this case, the accuracy of the beam pointing in the vertical dimension is not very high, which results in the beam pointing to the terminal device often being inaccurate. Figure 2 specifically shows this situation. The dashed line in Fig. 2 shows the optimal beam pointing for the user equipments UE1 and UE2, however, as shown, none of the four beams used by the base station BS are directed to the user equipments UE1 and UE2.

In the second case, in the case where the terminal device feeds back part of the PMI in the first phase, the network side device uses the partial PMI to transmit the user-specific beamforming CSI-RS. In this case, as the number of antennas increases, there is also a problem that the beam pointing is not accurate enough.

In the third case, in the case where the terminal device feeds back the simulated (precise) beam pointing in the first phase, the feedback overhead of the uplink increases due to the quantization burden of the analog beam.

In addition, in addition to the above problems, according to the current fifth-generation (5G) mobile communication standard, the number of antennas is increasing and the beam direction is narrower and narrower, so it will face more serious problems and challenges.

Summary of the invention

To this end, the present invention proposes a feedback mixed channel state information in a multi-antenna scenario. A solution that addresses one or more of the above issues.

According to an aspect of the present invention, an electronic device for wireless communication is provided, comprising processing circuitry configured to: perform a first channel measurement based on a first reference signal from a target communication device; The result of the first channel measurement determines a plurality of weight parameters, such that the composite channel obtained by weighting the preset plurality of channel features by using the plurality of weight parameters matches the actual channel, wherein the preset multiple Channel characteristics are known to the electronic device and the target communication device; and generating feedback information indicative of the plurality of weight parameters for the target communication device.

According to another aspect of the present invention, there is provided a method performed in a terminal device, comprising: performing a first channel measurement according to a first reference signal transmitted by a target communication device; determining more based on a result of the first channel measurement a weighting parameter, such that the composite channel obtained by weighting the preset plurality of channel features by using the plurality of weight parameters matches the actual channel, wherein the preset plurality of channel characteristics are the terminal device and The target communication device is known; generating feedback information indicating the plurality of weight parameters to be sent to the target communication device; performing second channel measurement according to the second reference signal sent by the target communication device, where The second reference signal is transmitted by the target communication device via a composite channel obtained by weighted combining the preset plurality of channel characteristics based on the plurality of weight parameters; and based on the second channel measurement The result is a channel measurement report generated for transmission to the target communication device.

According to another aspect of the present invention, an electronic device for wireless communication is provided, comprising processing circuitry configured to: generate a first reference signal to be transmitted to a target communication device; utilizing by the target The plurality of weight parameters indicated by the feedback information provided by the communication device are weighted and combined with the preset plurality of channel features to obtain a composite channel, wherein the plurality of weight parameters are used by the target communication device by using the Determining, by the reference signal, the first channel measurement, that the composite channel obtained by performing weighted combination of the preset plurality of channel features by using the plurality of weight parameters matches the actual channel, wherein the preset A plurality of channel features are known to the electronic device and the target communication device.

According to another aspect of the present invention, a method for performing in a network side device includes: transmitting a first reference signal to a target communication device; using a plurality of weight parameter pairs provided by the target communication device to preset Multiple channel characteristics are weighted and combined to obtain a composite channel, wherein the plurality of weight parameters are determined by the target communication device by performing first channel measurement by using the first reference signal, so that the plurality of The weighting parameter matches the preset combined channel features to obtain a composite channel that matches the actual channel, wherein The preset plurality of channel features are known by the network side device and the target communication device; transmitting a second reference signal to the target communication device via the composite channel; providing based on the target communication device Channel measurement report to configure a transmission channel, wherein the channel measurement report is obtained by the target communication device performing a second channel measurement by using the second reference signal.

DRAWINGS

The invention may be better understood by referring to the following description in conjunction with the drawings, wherein the same or similar reference numerals are used throughout the drawings. The drawings, which are included in the specification, and in the claims In the drawing:

Figure 1 schematically shows a time sequence diagram of a feedback mechanism for mixing channel state information.

Figure 2 shows schematically the inaccurate beam pointing.

Figure 3 illustrates a first conventional feedback mechanism for mixing channel state information.

4 is a signal flow diagram showing a feedback scheme of mixed channel state information in accordance with a first embodiment of the present invention.

Figure 5 illustrates a second conventional feedback mechanism for mixing channel state information.

6 shows a signal flow diagram of a feedback scheme for mixing channel state information in accordance with a second embodiment of the present invention.

Figure 7 shows a third conventional feedback mechanism for mixing channel state information.

FIG. 8 is a signal flow diagram showing a feedback scheme of mixed channel state information according to a third embodiment of the present invention.

Figure 9 schematically illustrates a radio frequency beamforming scheme.

10 and 11 respectively show the signaling flow in time in the case where the beam direction has been specified in advance and the beam direction is not specified in advance.

Fig. 12 shows a schematic block diagram of a terminal device according to the present invention.

Figure 13 shows a schematic block diagram of a network side device in accordance with the present invention.

Fig. 14 shows a schematic configuration block diagram of a smartphone as one example of a terminal device.

FIG. 15 shows a schematic configuration block diagram of an eNB as one example of a network side device.

Figure 16 shows a block diagram of a schematic configuration of computer hardware.

detailed description

To facilitate a better understanding of the technical solutions according to the present disclosure, some of the concepts used in the present disclosure are briefly described below.

A base station, such as an eNB, has multiple antennas that support multiple input multiple output (MIMO) technology. The use of MIMO technology enables base stations to utilize spatial domain to support spatial multiplexing, beamforming, and transmit diversity. Spatial multiplexing can be used to simultaneously transmit different data streams on the same frequency. These data streams can be transmitted to a single User Equipment (UE) to increase the data rate (which can be classified as SU-MIMO technology) or to multiple UEs to increase the total system capacity (which can be classified as MU-MIMO technology). This is accomplished by spatially precoding each data stream (ie, applying scaling and phase adjustment of the amplitude) and then transmitting each spatially precoded stream on the downlink through multiple transmit antennas. The spatially precoded data streams arrive at the UE(s) with different spatial signatures, which enables each of the UE(s) to recover one or more data streams destined for the UE. On the uplink, each UE transmits a spatially precoded data stream, which enables the base station to identify the source of each spatially precoded data stream.

Spatial multiplexing is typically used when the channel is in good condition. Beamforming can be used to concentrate the transmitted energy in one or more directions when channel conditions are less favorable. This can be achieved by spatially precoding the data for transmission over multiple antennas. In order to achieve good coverage at the cell edge, single stream beamforming transmissions can be used in conjunction with transmit diversity.

In the detailed description that follows, various aspects of an access network will be described with reference to a multiple input multiple output (MIMO) system that supports orthogonal frequency division multiplexing (OFDM) on the downlink. OFDM is a spread spectrum technique that modulates data onto a number of subcarriers within an OFDM symbol. These subcarriers are separated by a precise frequency. This separation provides "orthogonality" that enables the receiver to recover data from these subcarriers. In the time domain, a guard interval (e.g., a cyclic prefix) may be added to each OFDM symbol to combat OFDM inter-symbol interference. The uplink may compensate for peak-to-average power ratio (PAPR) using SC-FDMA in the form of discrete Fourier transform (DFT) extended OFDM signals.

The radio protocol architecture for the user plane and the control plane in LTE is described next. The radio protocol architecture for the UE and the eNB has three layers: Layer 1, Layer 2, and Layer 3. Layer 1 (L1 layer) is the lowest layer and implements various physical layer signal processing functions. The L1 layer will be referred to herein as the physical layer. Layer 2 (L2 layer) is above the physical layer and is responsible for the link between the UE and the eNB above the physical layer.

In the user plane, the L2 layer includes a Medium Access Control (MAC) sublayer, a Radio Link Control (RLC) sublayer, and a Packet Data Convergence Protocol (PDCP) sublayer, which terminate at the eNB on the network side. The UE may also have a number of upper layers above the L2 layer, including a network layer (eg, an IP layer) terminating at a public data network (PDN) gateway on the network side, and terminating at the other end of the connection (eg, far The application layer of the UE, server, etc.).

The PDCP sublayer provides multiplexing between different radio bearers and logical channels. The PDCP sublayer also provides header compression for upper layer data packets to reduce radio transmission overhead, provides security by ciphering data packets, and provides handover support for UEs between eNBs. The RLC sublayer provides segmentation and reassembly of upper layer data packets, retransmission of lost data packets, and reordering of data packets to compensate for out-of-order reception due to hybrid automatic repeat request (HARQ). The MAC sublayer provides multiplexing between logical channels and transport channels. The MAC sublayer is also responsible for allocating various radio resources (e.g., resource blocks) in one cell among the UEs. The MAC sublayer is also responsible for HARQ operations.

In the control plane, the radio protocol architecture for the UE and the eNB is substantially the same for the physical layer and the L2 layer, with the difference that there is no header compression function for the control plane. The control plane also includes a Radio Resource Control (RRC) sublayer in Layer 3 (L3 layer). The RRC sublayer is responsible for obtaining radio resources (ie, radio bearers) and for configuring the lower layers using RRC signaling between the eNB and the UE.

Briefly introduce various signal processing functions of the L1 layer (ie, physical layer) implemented on the base station side. These signal processing functions include encoding and interleaving to facilitate forward error correction (FEC) of the UE and based on various modulation schemes (eg, binary phase shift keying (BPSK), quadrature phase shift keying (QPSK), M phase shifting. Keying (M-PSK), M Quadrature Amplitude Modulation (M-QAM) mapping to the signal constellation. The encoded and modulated symbols are then split into parallel streams. Each stream is then mapped to an OFDM subcarrier, multiplexed with reference signals (eg, pilots) in the time and/or frequency domain, and then combined together using an Inverse Fast Fourier Transform (IFFT) to generate a carry The physical channel of the time domain OFDM symbol stream. The OFDM stream is spatially precoded to produce a plurality of spatial streams. Channel estimation can be used to determine coding and modulation schemes as well as for spatial processing. The channel estimate can be derived from reference signals and/or channel condition feedback transmitted by the UE. Each spatial stream is then provided to a different antenna via a separate transmitter. Each transmitter modulates the RF carrier with its own spatial stream for transmission.

At the UE, each receiver receives signals through its respective respective antenna. Each receiver recovers the information modulated onto the RF carrier and provides this information to the various signal processing functions of the L1 layer. Perform spatial processing on the information at the L1 layer to recover any destination destined for the UE Spatial flow. If there are multiple spatial streams destined for the UE, they can be combined into a single OFDM symbol stream. The OFDM symbol stream is then converted from the time domain to the frequency domain using a Fast Fourier Transform (FFT). The frequency domain signal includes a separate OFDM symbol stream for each subcarrier of the OFDM signal. The symbols on each subcarrier, as well as the reference signal, are recovered and demodulated by determining the signal constellation points most likely to be transmitted by the eNB. These soft decisions can be based on channel estimates. These soft decisions are then decoded and deinterleaved to recover the data and control signals originally transmitted by the eNB on the physical channel. These data and control signals are then provided to higher layer processing.

Full-dimensional MIMO (FD-MIMO) technology can greatly improve system capacity by using a two-dimensional antenna array with, for example, up to 64 antenna ports at the eNB. The benefits of using multiple antenna ports at the eNB may include small inter-cell interference and high beamforming gain. The use of a two-dimensional antenna array allows for UE-specific beamforming in both the horizontal and vertical directions.

In an FD-MIMO system, the number of transmit antennas at an eNB can be increased by, for example, 8 to 10 times compared to a conventional 8-antenna MIMO system. These additional transmit antennas provide greater beamforming gain and less interference to neighbor cells.

In conventional MIMO technology with a one-dimensional antenna array, UE-specific beamforming can be performed only in the horizontal direction. The shared vertical downtilt can be applied to multiple UEs.

In the FD-MIMO technique with a two-dimensional antenna array, UE-specific beamforming can be performed in both the horizontal direction and the vertical direction.

In traditional linear precoding, the eNB requires MIMO channel state information (CSI) for the full channel. For example, conventional beamforming/precoding methods rely on the availability of CSI for the entire transmit dimension (eg, instantaneous/statistical knowledge of the channel from each eNB transmit antenna to one or more UE receive antennas).

Such CSI is obtained either by the UE's Precoding Matrix Indicator (PMI) / Rank Indicator (RI) report, or by utilizing channel reciprocity. In a time division duplex (TDD) system, CSI is primarily obtained at the eNB by utilizing bidirectional channel reciprocity. In a Frequency Division Duplex (FDD) system, CSI is typically measured and quantized at the UE and then fed back to the eNB via a dedicated uplink channel. In general, the size of the codebook used for CSI quantization increases as the number of transmit antennas at the eNB increases.

The PMI/RI report of the UE may be based on pilot-assisted estimation of the downlink full channel. The pilot (or shared reference signal) overhead and downlink channel estimation complexity may be proportional to the number of eNB antennas. Therefore, the complexity of PMI/RI selection may increase as the number of eNB antennas increases.

As described above, conventional channel estimation and channel information feedback are problematic due to the increased number of transmit antennas. Therefore, a hybrid channel state information feedback mechanism is proposed in some known technical discussions.

Downlink reference signal

The downlink reference signal is a predefined signal occupying a specific resource element (RE) in a downlink time-frequency resource block (RB). In the LTE downlink, the following different types of reference signals are included:

Cell-specific reference signal (CRS): Generally refers to a common reference signal that can be used by all UEs in a cell.

Demodulation Reference Signal (DMRS): Embedded in the data for dedicated users.

Channel State Information Reference Signal (CSI-RS): used to estimate channel state information, thereby assisting resource scheduling and precoding of the base station.

Channel state information (CSI)

The channel state information is used to indicate the channel state of the channel between the base station and the UE. The channel state information may include a rank indicator (RI), a precoding matrix indicator (PMI), and a channel quality indicator (CQI).

The RI is information about the channel rank, which indicates the maximum number of layers that can carry different information in the same time-frequency resource.

The PMI is used to indicate an index of a specific precoding matrix in a codebook including a plurality of precoding matrices shared between a base station and a UE.

The CQI indicates the channel quality and can be used to help determine the corresponding modulation scheme and coding rate.

A CSI-RS indicator (CRI) is used to indicate a preferred CSI-RS resource, and the UE measures each CSI-RS resource and feeds back the recommended beam in the form of a CRI.

需要注意的是，基站配置的波束并不局限于垂直维度，也可以是水平维度，例如可以表示为

或者，波束也可以不局限于垂直维度和水平维度，例如可以表示为更通用的形式

Figure 3 shows a first conventional feedback mechanism for mixing channel state information. The network side device (hereinafter referred to as "base station") configures K beams for transmitting cell-specific beamforming CSI-RS. The cell-specific beamforming CSI-RS is, for example, a CSI-RS supported by a Class B eMIMO type (CLASS B eMIMO-Type) in the current version of the LTE-A communication standard, where each CSI-RS antenna port There are respective CSI-RS resources and a narrower beamwidth without covering the entire cell range, and at least some of the beams have different beam directions. For example, in the case of K=4, the K beams may correspond to 4 beams in the vertical dimension, expressed as

It should be noted that the beam configured by the base station is not limited to the vertical dimension, and may also be a horizontal dimension, for example, it may be expressed as

Alternatively, the beam may not be limited to vertical and horizontal dimensions, for example, may be represented as a more general form

对应于比特组合“00”,依次类推，第四个波束

对应于比特组合“11”。也就是说，当用户设备确定接收功率最强的波束后，可以仅使用2个比特将该波束通知给基站。然后，基站在步骤S330使用CRI所指示的优选波束，将用户专用的波束赋形CSI-RS发送至用户设备，用户设备通过对该CSI-RS进行测量后，在步骤S340将CSI反馈给基站，该CSI中可以包括例如RI/PMI/CQI。之后，基站在步骤S350根据由用户设备反馈的CSI来配置下行信道，从而经由物理下行共享信道(PDSCH)向用户设备发送经波束赋形的数据。用户设备在步骤S360反馈HARQ过程的应答信号，即肯定应答(ACK)或否定应答(NACK)。As shown in FIG. 3, the base station transmits a cell-dedicated beamforming CSI-RS to a terminal device (hereinafter simply referred to as "user equipment") via the configured four beams in step S310. The user equipment measures the received power (reference signal received power, RSRP) of the CSI-RS signal, and according to the measurement result, one beam with the strongest RSRP is fed back to the base station by CRI, as shown in step S320. Specifically, for 4 beams, CRI can indicate each beam with a different combination of 2 bits, for example, the first beam

Corresponding to the bit combination "00", and so on, the fourth beam

Corresponds to the bit combination "11". That is to say, after the user equipment determines the beam with the strongest received power, the beam can be notified to the base station using only 2 bits. Then, the base station sends the user-specific beamforming CSI-RS to the user equipment by using the preferred beam indicated by the CRI in step S330. After measuring the CSI-RS, the user equipment feeds back the CSI to the base station in step S340. Such CSI may include, for example, RI/PMI/CQI. Thereafter, the base station configures the downlink channel according to the CSI fed back by the user equipment in step S350, thereby transmitting the beamformed data to the user equipment via the Physical Downlink Shared Channel (PDSCH). The user equipment feeds back a response signal of the HARQ process, ie an acknowledgement (ACK) or a negative acknowledgement (NACK), in step S360.

The conventional feedback mechanism shown in FIG. 3 often has the following problem: as described above in connection with FIG. 2, since the number of configurable beams of the base station is small (the value of K is small), the CRI of the user equipment feedback indicates The beam is often not the beam most suitable for the user equipment, that is, the feedback beam often cannot be pointed to the user equipment accurately, which causes the base station to fail to use the ideal beam to transmit the user-specific CSI-RS in the second stage. .

作为用于发送小区专用的波束赋形CSI-RS的常规波束。然后，基站在步骤S402可以利用高层信令例如无线资源控制(RRC)信令，将关于所配置的波束P_v的信息通知给用户设备。例如，基站可以半静态地配置小区专用的常规波束赋形CSI-RS， 在重配置发生后将关于重新配置的小区专用的常规波束赋形CSI-RS的信息放入RRC信令以通知给用户设备。In response to the above problems, the present invention proposes a first embodiment which can improve the accuracy of the beamforming CSI-RS of the second stage. 4 is a signal flow diagram showing a feedback scheme of mixed channel state information in accordance with a first embodiment of the present invention. As shown in FIG. 4, the base station configures, for example, four preset vertical dimension beams in step S401.

As a conventional beam for transmitting cell-specific beamforming CSI-RS. Then, at step S402 the base station can use higher layer signaling, for example, radio resource control (RRC) signaling, the information about the configuration of the beam P _v notifies the user equipment. For example, the base station may semi-statically configure a cell-specific conventional beamforming CSI-RS, and put information about the reconfigured cell-specific regular beamforming CSI-RS into RRC signaling to notify the user after reconfiguration occurs. device.

其用于对该4个垂直维度波束进行线性加权组合。加权组合后得到的合成波束可以表示为

Then, the base station transmits a cell-specific non-precoded/non-beamformed CSI-RS to the user equipment in step S403, for example, in the current version of the LTE-A communication standard. CSI-RS supported by Class A eMIMO-Type, in which different CSI-RS antenna ports have the same CSI-RS resources, wide beamwidth and direction to cover the entire cell range. The user equipment measures the received CSI-RS and calculates a set of weight parameters _Cv , as shown in step S404. The set of weight parameters can be expressed as

It is used to linearly weight combine the four vertical dimension beams. The combined beam obtained after weighted combination can be expressed as

The user equipment can calculate the weight parameter _Cv using a plurality of methods, one of which is to maximize the received power RSRP of the CSI-RS, which can be expressed by the following mathematical formula (1):

[Math 1]

Wherein the column vector h represents the overall vertical dimension channel, s represents the CSI-RS of the normalized power, i ∈ [1, . . . , K], in particular, in this example, K=4.

As described above, by RRC signaling, the user equipment has learned information on the beam P _v configured by the base station. Regarding the overall vertical dimension channel h, the user equipment can be estimated, for example, from the conventional unprecoded/unbeamformed CSI-RS received at step S403. Finally, the user equipment obtains a set of weight parameters C _{v that} maximizes the RSRP of the cell-specific beamforming CSI-RS by the less complex search according to the above mathematical formula (1).

其元素是1/2的N次方。这样，每个权重参数可以仅使用2个比特来表示(如“00”，“01”，“10”，“11”)，而因为共有4个权重参数，因此用于反馈的总比特数为8个。此外作为另一示例，除了实数码本以外，还可以使用复数旋转码本，例如{e^jπ/2,e^j2π/2,e^j3π/2,e^j4π/2}，其中的各个元素对应于将单位圆在复平面进行等分后所获得的角度。以{e^jπ/2,e^j2π/2,e^j3π/2,e^j4π/2}为例，该向量包含4个元素，因此各个元素分别对应于将单位圆进行四等分后获得的四个角度，即，分别是0度，90度，180度和270度。本领域技术人员易于理解，如果上述向量中包含八个元素，则各个元素分别对应于将单位圆进行八等分后获得的各个角度。需要说明的是，本文中以4个垂直维度波束以及相应的4个权重参数为例来进行描述，但波束以及权重参数的数目并不限于此。Then, the user equipment feeds back the calculated weight parameter C _v corresponding to each preset vertical dimension CSI-RS beam to the base station in step S405. In order to reduce the burden of feedback via the physical uplink shared channel/physical uplink control channel (PUSCH/PUCCH), the elements in _Cv may be designed to be selected from a smaller parameter codebook. For example, but not limited to, the parameter codebook can be a real digital book.

Its element is 1/2 Nth power. Thus, each weight parameter can be represented by only 2 bits (such as "00", "01", "10", "11"), and since there are 4 weight parameters, the total number of bits used for feedback is 8. Further, as another example, in addition to the real codebook, you may also be used a plurality of rotary codebook, e.g. ^{{e jπ / 2, e j2π} / 2, e j3π / 2, e j4π / 2}, where each element corresponds to the The angle obtained after the unit circle is equally divided in the complex plane. To ^{{e jπ / 2, e j2π} / 2, e j3π / 2, e j4π / 2} as an example, the vector contains four elements, and therefore respectively correspond to the four quarters after the unit circle obtained The angles, that is, 0 degrees, 90 degrees, 180 degrees, and 270 degrees, respectively. It will be readily understood by those skilled in the art that if the above vector contains eight elements, each element corresponds to each angle obtained by octave the unit circle. It should be noted that, in this paper, four vertical dimension beams and corresponding four weight parameters are taken as an example, but the number of beams and weight parameters is not limited thereto.

The base station obtains the weight parameter fed back by the user equipment, and performs linear weight combining on the four vertical dimension beams using the group weight parameter in step S406 to obtain a composite beam, where the direction of the composite beam corresponds to enabling the user equipment to receive the CSI-RS. Power RSRP maximum direction. The base station then transmits the user-specific CSI-RS to the user equipment using the composite beam in step S407. The user equipment measures the CSI-RS in step S408, obtains channel state information (for example, RI/PMI/CQI) according to a conventional manner, and feeds back the channel state information to the base station in step S409, and then the base station according to the user in step S410 The channel state information fed back by the device configures the downlink channel to transmit beamformed data. Steps S409-S411 in FIG. 4 are respectively the same as the corresponding steps in FIG. 3, and therefore will not be described again.

According to the embodiment of the present invention, since the direction of the composite beam corresponds to the direction in which the actual received power of the user equipment is the strongest, the multiple weight parameters are fed back compared to the case where the user simply selects a certain beam for feedback. The scheme capable of obtaining a more accurate composite beam by weighted combination can improve the accuracy of the base station transmitting the user-specific CSI-RS in the second phase, and accordingly the user equipment can also provide more accurate channel state information feedback in the second phase. On the other hand, the signaling overhead of the embodiment of the present invention is significantly reduced compared to the direct feedback of the accurate overall channel h. small. In this way, a reasonable compromise between implementation complexity and signaling overhead is achieved.

FIG. 5 shows a second conventional feedback mechanism for mixing channel state information, which differs from FIG. 3 in steps S510-S530. Therefore, steps S510-S530 will be mainly described below, and descriptions of steps S540-S560 which are the same as steps S340-S360 in FIG. 3 are omitted.

The base station transmits a non-precoded (full port) CSI-RS in step S510. The user equipment measures all ports and calculates a partial PMI (indicating precoding matrix W1), which is long-term broadband information, representing a spatially wider beam. The user equipment then feeds back the calculated partial PMI (indicating the precoding matrix W1) to the base station in step S520. The base station transmits the user-specific CSI-RS to the user equipment using the beam indicated by the partial PMI, so that the user equipment performs the second-stage measurement, as shown in step S530.

The problem with this conventional feedback mechanism is that as the number of antennas increases, the coverage width of W1 will become narrower and narrower, and the beam direction most suitable for the user equipment may not be well reflected. Therefore, it is difficult for the user equipment to feed back the beam direction most suitable for itself through a single partial PMI, thereby affecting the accuracy of the channel measurement of the second stage.

In response to the above problems, the present invention proposes a second embodiment which can improve the accuracy of the beamforming CSI-RS of the second stage. 6 shows a signal flow diagram of a feedback scheme for mixing channel state information in accordance with a second embodiment of the present invention. As shown in FIG. 6, the base station transmits the CSI-RS of the all-port that is not precoded to the user equipment in step S601. The user equipment measures all ports and calculates a partial PMI (indicating the precoding matrix W1). W1 is represented by the broadband and long-term PMI groups in the two-stage PMI mechanism of the LTE system. However, as the 3GPP version evolves, the number of antenna ports increases, resulting in a narrowing of the coverage of a single W1. Therefore, in the present embodiment, the following situation is considered: the user equipment calculates and feeds back information about the plurality of precoding matrices W1 according to the all-port CSI-RS transmitted by the base station.

A plurality of (for example, M) preset W1s are represented as W ₁ ^all ={W ₁ ¹ , W ₁ ² , . . . , W ₁ ^M }, and similar to the first embodiment, the user equipment calculates for The plurality of W1s perform a linear weighted combination of a set of weight parameters _Cv such that the combined precoder obtained after the weighted combination is most suitable for the beam direction of the user equipment, as shown in step S602. The plurality of preset W1s and their corresponding PMIs are configured by the base station to the user equipment through high layer signaling, or are pre-defined by the communication protocol and pre-stored in the communication chip, so as to be known to the base station and the user equipment. For example, the weight parameter may be calculated by a method of maximizing the received power RSRP of the CSI-RS, as shown in the following mathematical formula (2):

[Math 2]

Among them, the meanings of the parameters h and s are the same as those in the mathematical formula (1), i ∈ [1, ..., M].

According to the above mathematical formula (2), the user equipment obtains a set of weight parameters C _v that maximizes the RSRP of the CSI-RS received in step S601, and returns the weight parameter C _v in step S603. To the base station.

因此，可以按照多个W1在码本中相同的顺序来反馈权重参数C_v中的元素

相应地，基站可按照关于W1的码本的知识来确定每一W1对应的权重参数，并进行后续的编码器合成。替选地，在另一个示例中，用户设备可以仅针对W1码本中最接近实际波束方向的部分数量的(例如n(n<M)个)W1确定相应的权重参数，在此情况下，在步骤S603用户设备还将所使用的n个W1通过部分PMI反馈给基站。基站在步骤S604利用接收到的权重参数C_v和所确定的多个W1进行线性加权组合，从而得到合成W1，即

然后，基站利用与该合成W1对应的波束将用户专用的CSI-RS发送至用户设备，如步骤S605所示。后续的步骤S606-S609与图4所示的第一实施例中的相应步骤相同，故不再赘述。In the above example, i∈[1,...,M], the user equipment determines the corresponding weight parameter for each W1.

Therefore, the elements in the weight parameter C _v can be fed back in the same order as the multiple W1s in the codebook.

Accordingly, the base station can determine the weight parameter corresponding to each W1 according to the knowledge about the codebook of W1, and perform subsequent encoder synthesis. Alternatively, in another example, the user equipment may determine a corresponding weight parameter only for a portion of the W1 codebook that is closest to the actual beam direction (eg, n(n<M)) W1, in which case, In step S603, the user equipment also feeds back the used n W1s to the base station through the partial PMI. The base station performs linear weighted combination using the received weight parameter C _v and the determined plurality of W1s in step S604, thereby obtaining a composite W1, ie

Then, the base station transmits the user-dedicated CSI-RS to the user equipment by using the beam corresponding to the composite W1, as shown in step S605. Subsequent steps S606-S609 are the same as the corresponding steps in the first embodiment shown in FIG. 4, and therefore will not be described again.

FIG. 7 shows a third conventional feedback mechanism for mixing channel state information, which is similar to the second conventional feedback mechanism shown in FIG. 5, with the main difference being step S720. That is, after the base station transmits the un-coded all-port CSI-RS to the user equipment in the first phase, the user equipment measures all ports and calculates the simulated (precise) beam direction instead of calculating the partial PMI. Then, the user equipment quantizes the calculated beam direction and feeds back to the base station (as shown in step S720) instead of the feedback part PMI.

The problem with the feedback mechanism is that the quantization loss is either large when the beam direction is quantized, or the precise beam direction causes the signaling overhead to be too large to be fed back to the base station via the uplink channel.

通知给用户设备，使得该组基向量为基站和用户设备所共知。然后，基站在步骤S802将未经预编码的全端口的CSI-RS发送至用户设备。用户设备在步骤S803测量全部端口，并且计算一个精准的最优波束方向

例如，用户设备在测量了全部端口之后，可以确定信道矩阵。然后，该用户设备可以对所确定的信道矩阵进行特征值分解以得到特征向量，并且将该特征向量作为最优波束方向

需要说明的是，本领域技术人员易于采用任何其它已知的方式来获得该最优波束方向

本发明并不限于上述示例。In response to the above problems, the present invention proposes a third embodiment which can improve the accuracy of the beamforming CSI-RS of the second stage. FIG. 8 is a signal flow diagram showing a feedback scheme of mixed channel state information according to a third embodiment of the present invention. As shown in FIG. 8, the base station first sets a set of base vectors through high layer signaling such as RRC in step S801.

The user equipment is notified such that the set of base vectors is known to the base station and the user equipment. Then, the base station transmits the non-precoded all-port CSI-RS to the user equipment in step S802. The user equipment measures all ports in step S803 and calculates a precise optimal beam direction.

For example, the user equipment can determine the channel matrix after measuring all ports. Then, the user equipment may perform eigenvalue decomposition on the determined channel matrix to obtain a feature vector, and use the feature vector as an optimal beam direction.

It should be noted that those skilled in the art can easily obtain the optimal beam direction by using any other known manner.

The invention is not limited to the above examples.

因此用户设备可以使用该组基向量的线性组合

来表示(模拟)所计算的最优波束方向

为此目的，用户设备需要确定用于加权组合的权重参数C_v。例如，用户设备可以通过满足最大化相关性和发送功率约束来确定该组权重参数C_v，如以下数学式(3)所示：In this embodiment, since the base station and the user equipment know a set of basis vectors

Thus the user equipment can use a linear combination of the set of basis vectors

To represent (simulate) the calculated optimal beam direction

For this purpose, the user equipment needs to determine the weighting parameter _Cv for the weighted combination. For example, the user equipment can determine the set of weight parameters _Cv by satisfying the maximum correlation and the transmit power constraints, as shown in the following mathematical formula (3):

[Math 3]

和

的相关性最大化且同时满足发送功率约束的一组权重参数C_v，然后用户设备将所计算的权重参数C_v反馈给基站，如步骤S804所示。基站在步骤S805利用接收到的权重参数C_v对先前已知的多个基向量

进行加权组合，得到合成波束方向

可以认为

表示了最接近于最优波束方向

的波束方向。因此，基站可以利用

所对应的波束将用户专用的CSI-RS发送至用户设备，如步骤S806所示。后续的步骤S807-S810与图4所示的第一实施例中的相应步骤相同，故不再赘述。The user equipment can be obtained by the search algorithm according to the above mathematical formula (3).

with

The correlation is maximized and simultaneously satisfies a set of weight parameters C _{v of the} transmit power constraint, and then the user equipment feeds back the calculated weight parameter C _v to the base station, as shown in step S804. The base station uses the received weight parameter C _v to the previously known multiple base vectors in step S805.

Perform weighted combination to obtain the combined beam direction

It can be considered

Indicates the closest to the optimal beam direction

Beam direction. Therefore, the base station can utilize

The corresponding beam transmits the user-specific CSI-RS to the user equipment, as shown in step S806. Subsequent steps S807-S810 are the same as the corresponding steps in the first embodiment shown in FIG. 4, and therefore will not be described again.

A fourth embodiment in accordance with the present invention is presented below for an ongoing radio frequency beamforming scheme (also referred to as an analog beamforming scheme). Figure 9 schematically illustrates the radio frequency beamforming scheme. As shown in FIG. 9, on the base station side, the digital precoder 910 precodes the input K data streams, and the precoded data is transmitted to the analog precoder 920 via the K radio frequency chains, and the analog precoder 920 Includes multiple phase shifters and adders. After processing by the analog precoder 920, the signal is sent to the user equipment via the M antenna units. On the user equipment side, signals from the base station are received via N antenna units, and the received signals are then output through a plurality of phase shifters to an RF chain. Subsequent processing on the user equipment side is omitted in the figure in order to unnecessarily obscure the gist of the present invention. It should be noted that only one user equipment is schematically illustrated in FIG. 9, and in practice, there are usually a plurality of user equipments that communicate with the base station.

In FIG. 9, the analog precoder 920 performs beamforming based on the radio frequency beamforming matrix F=[f ₁ , . . . , f _K ], and the radio frequency beamforming matrix F is derived from a codebook set of size K. Different codebooks can form beams that are pointed by different spaces. Generally, a base station may use multiple beams to transmit a reference signal in different time periods, which may be called Beam Sweeping, in order to allow a user equipment to measure multiple beams to determine which beam is most suitable for the user equipment, and then The number of the most suitable beam is fed back to the base station.

其于中，C_k是权重参数，k∈[1,...,K]。用户设备通过在不同的线性组合之 下确定合成波束上的参考信号接收功率RSRP，来确定是否存在比现有的K个波束更优的波束方向，即，使得接收功率RSRP更大的波束方向，如以下数学式(4)所示：The present invention proposes a fourth embodiment for the radio frequency beamforming scheme. In this embodiment, it is assumed that the user equipment measures K beams P=[p ₁ , . . . , p _K ] in the first stage, and finds that there are no beams suitable for itself in the K beams, that is, K. The pointing accuracy of the beam is not very high. In this case, the user equipment may attempt to obtain a beam more suitable for itself by linearly weighting the K beams. For example, a linear combination can be expressed as

In it, C _k is the weight parameter, k ∈ [1,..., K]. The user equipment determines whether there is a better beam direction than the existing K beams by determining the reference signal received power RSRP on the composite beam under different linear combinations, that is, making the received power RSRP larger beam direction, As shown in the following formula (4):

[Math 4]

Among them, the meaning of the parameter h is the same as the meaning in the mathematical formula (1), k ∈ [1, ..., K].

If the combined beam obtained by the weighted combination of the K beams is more suitable for the beam direction of the user equipment than each of the K beams, the user equipment feeds back the weight parameter C _k corresponding to the weighted combination to the base station. In order for the base station to use the weight parameter C _{k to} obtain a beam direction that is more precisely directed to the user equipment, and to transmit the user-specific CSI-RS using the obtained beam direction. On the other hand, if there is no composite beam that is better than the K beams, the user equipment feeds back one beam with the strongest signal receiving power among the K beams to the base station.

FIG. 10 shows a signaling flow in time in the case where the beam direction is not specified in advance in the communication protocol, and FIG. 11 shows a signaling flow in the case where the beam direction has been previously specified in the communication protocol.

As shown in FIG. 10, in an example in which the communication protocol does not specify a beam direction, the base station needs to notify the user equipment of the configured beam direction by using RRC signaling before transmitting the cell-specific CSI-RS, as shown in step S1010. Through this step, both the base station and the user equipment know the coordinate system that the optimal beam direction can be projected, so the user equipment only needs to feed back the projection parameters of the optimal beam direction in the coordinate system (ie, as described above). The weight parameter "), the base station can recover the optimal beam direction according to the projection parameters. After notifying the configured beam direction to the user equipment, the base station may transmit a cell-specific CSI-RS to the user equipment in step S1020. After the user equipment measures the CSI-RS, the weight parameter is calculated by the above method, and the weight parameter is fed back to the base station in step S1030. The base station performs a linear weighted combination using the received weight parameters to obtain an optimal beam direction that more accurately points to the user equipment, and transmits the user-specific CSI-RS using the optimal beam, as shown in step S1040. After measuring the CSI-RS received in step S1040, the user equipment generates CSI in a conventional manner and reports it to the base station in step S1050.

Then, the next CSI feedback cycle is entered, and the signaling flow in the next feedback cycle is basically the same as that described above, except that step S1010 is omitted, and the process starts directly with step S1020. Since the beam direction configured by RRC signaling is a longer-term configuration, that is, by one configuration, the configured beam direction can be used in multiple feedback periods, so it is not necessary to perform step S1010 in each feedback period. Further, the cell-specific CSI-RS transmitted by the base station in step S1020 is also a long-term configuration, and the user-specific CSI-RS transmitted in step S1040 is a short-term configuration. Generally, in 3GPP, long-term configuration can be configured by high-layer signaling, such as RRC signaling, and the period is, for example, about 100 ms or longer. The short-term configuration can be configured by a physical layer control channel such as downlink control information (DCI), and the period is configured. The shortest can be, for example, 1 ms.

The signaling flow shown in FIG. 11 is basically the same as the flow of FIG. 10 except that the initial step S1010 is omitted. This is because in the case where the beam direction has been specified in the communication protocol, it is not necessary to configure the beam by the base station via RRC signaling. Steps S1120-S1150 in Fig. 11 are the same as steps S1020-S1050 in Fig. 10, respectively.

12 and 13 respectively show schematic block diagrams of a terminal device and a network side device according to the present invention.

As shown in FIG. 12, the terminal device 1200 includes a processing unit 1210, a storage unit 1220, and a transceiver unit 1230. The transceiver unit 1230 includes one or more antennas for transmitting and receiving signals with the network side device.

The storage unit 1220 is configured to store a codebook. As described above, the terminal device 1200 may design the weight parameter as an element in the codebook when determining the weight parameter, so that each weight parameter may be indicated by a small number of bits. This reduces the feedback overhead. In addition, the storage unit 1220 also stores channel characteristics that are common to the network side device and the terminal device, and the well-known channel characteristics are represented in the first embodiment as a plurality of CSI-RSs configured by the base station for transmitting cell-specific CSI-RSs. The beam, which is represented in the second embodiment as a plurality of partial PMIs (W1) calculated and fed back by the terminal device, appears as a preset set of base vectors in the third embodiment, and is represented as a base station in the fourth embodiment. Send multiple beams of the reference signal.

The processing unit 1210 further includes a measurement unit 1211, a weight parameter determination unit 1212, and a CSI determination unit 1213. The measuring unit 1211 is configured to perform measurement on reference signals transmitted by the network side device, such as a cell-specific CSI-RS and a user-specific CSI-RS. The weight parameter determining unit 1212 calculates a weight parameter for linearly weighting the well-known channel characteristics based on the measurement result of the cell-specific CSI-RS by the measuring unit 1211, and refers to the weighting parameter for the well-known channel feature. The codebook stored in the storage unit 1220 generates feedback information including an index of the codeword corresponding to each weight parameter (as described above) Said "00", "01", etc.). The CSI determining unit 1213 generates CSI (for example, including RI/PMI/CQI) according to a measurement result of the user-specific CSI-RS by the measuring unit 1211, and transmits the CSI to the network side device via the transceiving unit 1230.

As shown in FIG. 13, the network side device 1300 includes a processing unit 1310, a storage unit 1320, a codebook update unit 1330, and a transceiver unit 1340. The transceiver unit 1340 includes a plurality of antennas for transmitting and receiving signals with the terminal device. The storage unit 1320 stores the same codebook as the codebook in the terminal device, so that the weight parameter can be obtained based on the received feedback information and the codebook. Further, similarly to the storage unit 1220 in the terminal device, the storage unit 1320 also stores channel characteristics that are well known by the network side device and the terminal device. The codebook updating unit 1330 is configured to update the stored codebook, that is, the network side device 1300 semi-statically configures the codebook. Further, the codebook updating unit 1330 also generates an instruction regarding the updated codebook to notify the terminal device of the update of the codebook via the transceiving unit 1340.

The processing unit 1310 includes a reference signal generating unit 1311, a combined beam determining unit 1312, and a channel configuring unit 1313. The reference signal generating unit 1311 is configured to generate channel state information reference information (CSI-RS), such as a cell-specific CSI-RS and a user-dedicated CSI-RS, for transmission to the terminal device via the transceiver unit 1340. The composite beam determining unit 1312 obtains a weight parameter by referring to the codebook stored in the storage unit 1320 according to the feedback information from the terminal device, and uses the weight parameter to linearly weight combine the well-known channel features to obtain a pointing to the terminal device. A more precise synthetic beam. The transceiver unit 1340 transmits the user-specific CSI-RS to the terminal device by using the composite beam determined by the combined beam determining unit 1312, so that the terminal device generates the CSI by measurement. The channel configuration unit 1313 configures the downlink transport channel in accordance with a conventional method based on the CSI fed back by the terminal device.

The present invention provides a more accurate solution for obtaining mixed channel state information. In this solution, the terminal device does not simply feed back a certain beam direction configured by the network side device in the first phase, but feeds back a weighted combination of multiple channel features that are well known to the terminal device and the network side device. The weighting parameter is such that the network side device uses the weighting parameter to perform weighted combination of the plurality of channel features to match the actual channel, so that the reference signal can be transmitted in a more precise manner in the second phase. As used herein, "matching" means that the resulting composite channel direction corresponds to the actual channel direction that is most suitable for the terminal device (i.e., the channel direction that most accurately points to the terminal device). The method of judging whether or not "matching" may include, for example, the received power RSRP maximization criterion described in the first embodiment and the correlation maximization criterion described in the third embodiment. It should be noted that those skilled in the art can easily design other judgment methods according to actual needs, thereby determining weight parameters for weighted combination, and therefore The invention is not limited to the two criteria described above.

Since the network side device can transmit the user-specific reference signal with a more accurate beam, the terminal device can perform more accurate channel measurement, and finally provide more accurate CSI feedback for the network side device.

The invention can be applied to various products. For example, the network side device or base station in the above embodiment may include any type of evolved Node B (eNB), such as a macro eNB and a small eNB. The small eNB may be an eNB covering a cell smaller than the macro cell, such as a pico eNB, a micro eNB, and a home (femto) eNB. Alternatively, the network side device or base station may also include any other type of base station, such as a NodeB and a base transceiver station (BTS). The base station can include: a body (also referred to as a base station device) configured to control wireless communication; and one or more remote wireless headends (RRHs) disposed at a different location than the body. In addition, various types of terminal devices can also operate as base stations by performing base station functions temporarily or semi-persistently.

On the other hand, the terminal device or user device in the above embodiment may be implemented as, for example, a communication terminal device such as a smart phone, a tablet personal computer (PC), a notebook PC, a portable game terminal, a portable/encrypted dog type mobile router, and A digital camera device or an in-vehicle terminal device (such as a car navigation device) may also be implemented as a terminal device that performs machine-to-machine (M2M) communication, also referred to as a machine type communication (MTC) terminal device. Further, the terminal device or user device may also be a wireless communication module (such as an integrated circuit module including a single wafer) installed on each of the above terminals.

The implementation of the terminal device or user device will be described below with reference to FIG. 14 with a smartphone as an example.

Fig. 14 is a block diagram showing a schematic configuration of a smartphone. As shown in FIG. 14, the smart phone 2500 includes a processor 2501, a memory 2502, a storage device 2503, an external connection interface 2504, an imaging device 2506, a sensor 2507, a microphone 2508, an input device 2509, a display device 2510, a speaker 2511, and a wireless communication interface. 2512, one or more antenna switches 2515, one or more antennas 2516, a bus 2517, a battery 2518, and an auxiliary controller 2519.

The processor 2501 may be, for example, a CPU or a system on chip (SoC), and controls the functions of the application layer and the other layers of the smartphone 2500. The memory 2502 includes a RAM and a ROM, and stores data and programs executed by the processor 2501. The storage device 2503 may include a storage medium such as a semiconductor memory and a hard disk. The external connection interface 2504 is an interface for connecting an external device such as a memory card and a universal serial bus (USB) device to the smartphone 2500.

Camera 2506 includes an image sensor (such as a charge coupled device (CCD) and complementary Metal oxide semiconductor (CMOS)) and generate a captured image. Sensor 2507 can include a set of sensors, such as a measurement sensor, a gyro sensor, a geomagnetic sensor, and an acceleration sensor. The microphone 2508 converts the sound input to the smartphone 2500 into an audio signal. The input device 2509 includes, for example, a touch sensor, a keypad, a keyboard, a button, or a switch configured to detect a touch on the screen of the display device 2510, and receives an operation or information input from a user. The display device 2510 includes screens such as a liquid crystal display (LCD) and an organic light emitting diode (OLED) display, and displays an output image of the smartphone 2500. The speaker 2511 converts the audio signal output from the smartphone 2500 into a sound.

The wireless communication interface 2512 supports any cellular communication scheme (such as LTE and LTE-Advanced) and performs wireless communication. Wireless communication interface 2512 may generally include, for example, a baseband (BB) processor 2513 and radio frequency (RF) circuitry 2514. The BB processor 2513 can perform, for example, encoding/decoding, modulation/demodulation, and multiplexing/demultiplexing, and performs various types of signal processing for wireless communication. Meanwhile, the RF circuit 2514 may include, for example, a mixer, a filter, and an amplifier, and transmits and receives a wireless signal via the antenna 2516. The wireless communication interface 2512 may be a chip module on which the BB processor 2513 and the RF circuit 2514 are integrated. As shown in FIG. 14, the wireless communication interface 2512 can include a plurality of BB processors 2513 and a plurality of RF circuits 2514. However, the wireless communication interface 2512 can also include a single BB processor 2513 or a single RF circuit 2514.

Moreover, in addition to the cellular communication scheme, the wireless communication interface 2512 can also support additional types of wireless communication schemes, such as short-range wireless communication schemes, near field communication schemes, and wireless local area network (LAN) schemes. In this case, the wireless communication interface 2512 can include a BB processor 2513 and RF circuitry 2514 for each wireless communication scheme.

Each of the antenna switches 2515 switches the connection destination of the antenna 2516 between a plurality of circuits included in the wireless communication interface 2512, such as circuits for different wireless communication schemes.

Each of the antennas 2516 includes a single or multiple antenna elements (such as multiple antenna elements included in a MIMO antenna) and is used by the wireless communication interface 2512 to transmit and receive wireless signals. As shown in FIG. 14, smart phone 2500 can include multiple antennas 2516. However, smart phone 2500 can also include a single antenna 2516.

Additionally, smart phone 2500 can include an antenna 2516 for each wireless communication scheme. In this case, the antenna switch 2515 can be omitted from the configuration of the smartphone 2500.

The bus 2517 connects the processor 2501, the memory 2502, the storage device 2503, and the external connection. The interface 2504, the imaging device 2506, the sensor 2507, the microphone 2508, the input device 2509, the display device 2510, the speaker 2511, the wireless communication interface 2512, and the auxiliary controller 2519 are connected to each other. Battery 2518 provides power to various components of smart phone 2500 via feeders, which are shown partially as dashed lines in the figure. The secondary controller 2519 operates the minimum required function of the smartphone 2500, for example, in a sleep mode.

In the smartphone 2500 shown in FIG. 14, the transceiver of the terminal device can be implemented by the wireless communication interface 2512. At least a portion of the functions of the functional units of the terminal device may also be implemented by the processor 2501 or the auxiliary controller 2519. For example, the power consumption of the battery 2518 can be reduced by performing a portion of the functions of the processor 2501 by the auxiliary controller 2519. Further, the processor 2501 or the auxiliary controller 2519 can perform at least a part of the functions of the respective functional units of the terminal device by executing the program stored in the memory 2502 or the storage device 2503.

The implementation of the network side device or base station will be described below with reference to FIG. 15 with the eNB as an example.

FIG. 15 shows a block diagram of a schematic configuration of an eNB. As shown in FIG. 15, the eNB 2300 includes one or more antennas 2310 and base station devices 2320. The base station device 2320 and each antenna 2310 may be connected to each other via a radio frequency (RF) cable.

Each of the antennas 2310 includes a single or multiple antenna elements, such as multiple antenna elements included in a multiple input multiple output (MIMO) antenna, and is used by the base station device 2320 to transmit and receive wireless signals. As shown in FIG. 15, the eNB 2300 may include a plurality of antennas 2310. For example, multiple antennas 2310 can be compatible with multiple frequency bands used by eNB 2300. Although FIG. 15 shows an example in which the eNB 2300 includes a plurality of antennas 2310, the eNB 2300 may also include a single antenna 2310.

The base station device 2320 includes a controller 2321, a memory 2322, a network interface 2323, and a wireless communication interface 2325.

The controller 2321 can be, for example, a CPU or a DSP, and operates various functions of higher layers of the base station device 2320. For example, controller 2321 generates data packets based on data in signals processed by wireless communication interface 2325 and delivers the generated packets via network interface 2323. The controller 2321 can bundle data from a plurality of baseband processors to generate bundled packets and deliver the generated bundled packets. The controller 2321 may have a logical function that performs control such as radio resource control, radio bearer control, mobility management, admission control, and scheduling. This control can be performed in conjunction with nearby eNBs or core network nodes. The memory 2322 includes a RAM and a ROM, and stores programs and various classes executed by the controller 2321. Type of control data (such as terminal list, transmission power data, and scheduling data).

The network interface 2323 is a communication interface for connecting the base station device 2320 to the core network 2324. Controller 2321 can communicate with a core network node or another eNB via network interface 2323. In this case, the eNB 2300 and the core network node or other eNBs may be connected to each other through a logical interface such as an S1 interface and an X2 interface. The network interface 2323 can also be a wired communication interface or a wireless communication interface for wireless backhaul lines. If the network interface 2323 is a wireless communication interface, the network interface 2323 can use a higher frequency band for wireless communication than the frequency band used by the wireless communication interface 2325.

The wireless communication interface 2325 supports any cellular communication schemes, such as Long Term Evolution (LTE) and LTE-Advanced, and provides wireless connectivity to terminals located in cells of the eNB 2300 via the antenna 2310. Wireless communication interface 2325 can typically include, for example, BB processor 2326 and RF circuitry 2327. The BB processor 2326 can perform, for example, encoding/decoding, modulation/demodulation, and multiplexing/demultiplexing, and performs layers (eg, L1, Medium Access Control (MAC), Radio Link Control (RLC), and Packet Data Convergence Protocol ( PDCP)) Various types of signal processing. Instead of controller 2321, BB processor 2326 may have some or all of the above described logic functions. The BB processor 2326 can be a memory that stores a communication control program, or a module that includes a processor and associated circuitry configured to execute the program. The update program can cause the functionality of the BB processor 2326 to change. The module can be a card or blade that is inserted into the slot of the base station device 2320. Alternatively, the module can also be a chip mounted on a card or blade. Meanwhile, the RF circuit 2327 may include, for example, a mixer, a filter, and an amplifier, and transmits and receives a wireless signal via the antenna 2310.

As shown in FIG. 15, the wireless communication interface 2325 can include a plurality of BB processors 2326. For example, multiple BB processors 2326 can be compatible with multiple frequency bands used by eNB 2300. As shown in FIG. 15, the wireless communication interface 2325 can include a plurality of RF circuits 2327. For example, multiple RF circuits 2327 can be compatible with multiple antenna elements. Although FIG. 15 illustrates an example in which the wireless communication interface 2325 includes a plurality of BB processors 2326 and a plurality of RF circuits 2327, the wireless communication interface 2325 may also include a single BB processor 2326 or a single RF circuit 2327.

In the eNB 2300 shown in FIG. 15, the transceiver of the base station side device can be implemented by the wireless communication interface 2325. At least a portion of the functionality of each unit may also be performed by controller 2321. For example, the controller 2321 can perform at least a portion of the functions of the units by executing a program stored in the memory 2322.

The various devices or units described herein are only logical and do not strictly correspond to physical devices or entities. For example, the functionality of each unit described in this article may consist of multiple physical realities. The functionality of the multiple units described herein may be implemented by a single physical entity. In addition, it should be noted that the features, components, elements, steps, and the like described in one embodiment are not limited to the embodiment, but may be applied to other embodiments, for example, in place of specific features and components in other embodiments. , elements, steps, etc., or combined with them.

16 is a block diagram showing an example configuration of computer hardware that executes the scheme of the present invention in accordance with a program.

In the computer 1600, a central processing unit (CPU) 1601, a read only memory (ROM) 1602, and a random access memory (RAM) 1603 are connected to each other through a bus 1604.

Input/output interface 1605 is further coupled to bus 1604. The input/output interface 1605 is connected to an input unit 1606 formed by a keyboard, a mouse, a microphone, or the like; an output unit 1607 formed of a display, a speaker, or the like; a storage unit 1608 formed of a hard disk, a nonvolatile memory, or the like; A communication unit 1609 formed of a network interface card (such as a local area network (LAN) card, a modem, etc.); and a drive 1610 that drives the removable medium 1611, such as a magnetic disk, an optical disk, a magneto-optical disk, or a semiconductor memory.

In the computer having the above structure, the CPU 1601 loads the program stored in the storage unit 1608 into the RAM 1603 via the input/output interface 1605 and the bus 1604, and executes the program to execute the above processing.

A program to be executed by a computer (CPU 1601) may be recorded on a removable medium 1611 as a package medium, such as a magnetic disk (including a floppy disk), an optical disk (including a compact disk-read only memory (CD-ROM)), A digital versatile disc (DVD) or the like, a magneto-optical disc, or a semiconductor memory is formed. Further, a program to be executed by a computer (CPU 1601) can also be provided via a wired or wireless transmission medium such as a local area network, the Internet, or digital satellite broadcasting.

When the removable medium 1611 is installed in the drive 1610, the program can be installed in the storage unit 1608 via the input/output interface 1605. In addition, the program can be received by the communication unit 1609 via a wired or wireless transmission medium, and the program is installed in the storage unit 1608. Alternatively, the program may be pre-installed in the ROM 1602 or the storage unit 1608.

The program to be executed by the computer may be a program that performs processing in accordance with the order described in this specification, or may be a program that executes processing in parallel or performs processing when needed, such as when called.

The embodiments and technical effects of the present invention have been described in detail above with reference to the accompanying drawings, but the scope of the present invention is not limited thereto. It should be understood by one of ordinary skill in the art that, depending on the design Various modifications and changes may be made to the embodiments discussed herein without departing from the principles and spirit of the invention. The scope of the invention is defined by the appended claims or their equivalents.

Further, the present invention can also be configured as follows.

An electronic device for wireless communication, comprising processing circuitry configured to: perform a first channel measurement based on a first reference signal from a target communication device; determine a plurality of based on a result of the first channel measurement The weighting parameter is such that the composite channel obtained by weighting the preset plurality of channel features by using the plurality of weight parameters matches the actual channel, wherein the preset plurality of channel characteristics are the electronic device and the The target communication device is well known; and generating feedback information indicating the plurality of weight parameters for the target communication device.

The processing circuit is further configured to: determine the plurality of weight parameters based on a preset codebook, wherein the preset codebook is a real digital book or a plurality of rotated codebooks, and is the electronic device And the target communication device is well known.

The feedback information includes an index of a codeword in the codebook corresponding to each weight parameter.

Wherein the preset codebook is semi-statically configured by the target communication device, the processing circuit further configured to acquire an indication of the updated codebook from the target communication device.

Wherein the processing circuit is further configured to: perform a second channel measurement according to a second reference signal from the target communication device, wherein the second reference signal is the target communication device via the plurality of weights And transmitting, by the weighted combination of the preset plurality of channel characteristics, the synthesized channel; and generating a channel measurement report for the target communication device based on the result of the second channel measurement.

The preset multiple channel features include a preset plurality of channel directions.

The preset multiple channel features include a preset plurality of base vectors.

The preset multiple channel directions correspond to preset multiple beams.

The preset multiple channel directions correspond to a preset plurality of precoding matrices.

The condition that the composite channel obtained by weighting the preset multiple channel features by using the multiple weight parameters matches the actual channel is that the first reference signal is compared according to the synthesized channel. The receiving power is the largest.

The processing circuit is further configured to: estimate an actual channel according to the first channel measurement, where the preset plurality of channel features are weighted by using the plurality of weight parameters The condition that the combined composite channel obtained by combining the actual channel matches is that the composite channel has the greatest correlation with the estimated actual channel.

The first reference signal sent by the target communication device is not precoded.

The electronic device is implemented as a terminal device, and the electronic device further includes: a memory, the memory is configured to store the preset multiple channel features; one or more antennas, and the antenna is used for The target communication device transmits a signal or receives a signal from the target communication device.

A method performed in a terminal device, comprising: performing a first channel measurement according to a first reference signal transmitted by a target communication device; determining a plurality of weight parameters based on a result of the first channel measurement, such that the plurality of The weighting parameter matches the preset combined channel of the plurality of channel features to the actual channel, wherein the preset plurality of channel features are known by the terminal device and the target communication device; generating And indicating feedback information of the plurality of weight parameters to be sent to the target communication device; performing second channel measurement according to the second reference signal sent by the target communication device, wherein the second reference signal is the target Transmitting, by the communication device, a composite channel obtained by weighting the predetermined plurality of channel characteristics based on the plurality of weight parameters; and generating a channel measurement report based on a result of the second channel measurement to transmit to the The target communication device.

An electronic device for wireless communication, comprising processing circuitry configured to: generate a first reference signal to be transmitted to a target communication device; utilize a plurality of feedback information provided by the target communication device Weighting parameters, weighting a plurality of preset channel characteristics to obtain a composite channel, wherein the plurality of weight parameters are determined by the target communication device by performing first channel measurement by using the first reference signal The composite channel obtained by weighting and combining the preset plurality of channel features by using the plurality of weight parameters is matched with an actual channel, wherein the preset plurality of channel features are the electronic device and The target communication device is well known.

Wherein the processing circuit is further configured to: generate a second reference signal to be transmitted to the target communication device, wherein the second reference signal is transmitted via the composite channel; based on a channel provided by the target communication device A measurement report is configured to configure a transmission channel, wherein the channel measurement report is obtained by the target communication device performing a second channel measurement by using the second reference signal.

The target communication device determines the plurality of weight parameters based on a preset codebook, wherein the preset codebook is a real digital book or a plurality of rotated codebooks, and is the target communication. The device and the electronic device are well known.

The feedback information includes an index of a codeword in the codebook corresponding to each weight parameter.

Wherein the processing circuit is further configured to: semi-statically configure the preset codebook and generate an indication of the updated codebook for the target communication device.

The preset multiple channel features include a preset plurality of channel directions.

The preset multiple channel features include a preset plurality of base vectors.

The preset multiple channel directions correspond to preset multiple beams.

The preset multiple channel directions correspond to a preset plurality of precoding matrices.

The condition that the composite channel obtained by weighting the preset multiple channel features by using the multiple weight parameters matches the actual channel is that the first reference signal is compared according to the synthesized channel. The receiving power is the largest.

The first reference signal sent to the target communication device is not precoded.

The electronic device is implemented as a network side device, and the electronic device further includes: a memory, the memory is configured to store the preset multiple channel features; and multiple antennas, the multiple antennas are used to The target communication device transmits a signal or receives a signal from the target communication device.

A method performed in a network side device, comprising: transmitting a first reference signal to a target communication device; weighting a plurality of preset channel characteristics by using a plurality of weight parameters provided by the target communication device, to Obtaining a composite channel, wherein the plurality of weight parameters are determined by the target communication device by performing first channel measurement by using the first reference signal, so that the preset is used by using the multiple weight parameters The composite channel obtained by performing weighted combination of the channel characteristics matches the actual channel, wherein the preset plurality of channel characteristics are known by the network side device and the target communication device; Transmitting a reference signal to the target communication device; configuring a transport channel based on a channel measurement report provided by the target communication device, wherein the channel measurement report is that the target communication device performs a second by utilizing the second reference signal Obtained by channel measurement.

Claims (29)

An electronic device for wireless communication, comprising a processing circuit, the processing circuit being configured to: Performing a first channel measurement according to a first reference signal from the target communication device; Determining, according to the result of the first channel measurement, a plurality of weight parameters, so that the composite channel obtained by weighting the preset plurality of channel features by using the plurality of weight parameters matches the actual channel, wherein the preset Multiple channel characteristics are known to the electronic device and the target communication device; Feedback information indicative of the plurality of weight parameters is generated for use by the target communication device. The electronic device of claim 1, wherein the processing circuit is further configured to: determine the plurality of weight parameters based on a preset codebook, wherein the preset codebook is a real digital book or a plurality The codebook is rotated and is known to the electronic device and the target communication device. The electronic device of claim 2, wherein the feedback information comprises an index of a codeword in the codebook corresponding to each weight parameter. The electronic device of claim 2, wherein the predetermined codebook is semi-statically configured by the target communication device, the processing circuit further configured to acquire an updated codebook from the target communication device Instructions. The electronic device of claim 1 wherein said processing circuit is further configured to: Performing a second channel measurement according to a second reference signal from the target communication device, wherein the second reference signal is that the target communication device pairs the preset plurality of channel characteristics based on the plurality of weight parameters Transmitting a composite channel obtained by weighted combination; and A channel measurement report is generated for the target communication device based on the results of the second channel measurement. The electronic device of claim 1, wherein the predetermined plurality of channel characteristics comprises a preset plurality of channel directions. The electronic device of claim 1, wherein the predetermined plurality of channel characteristics comprises a preset plurality of basis vectors. The electronic device of claim 6, wherein the preset plurality of channel directions correspond to a preset plurality of beams. The electronic device of claim 6, wherein the preset plurality of channel directions correspond to a preset plurality of precoding matrices. The electronic device of claim 1, wherein the first reference signal corresponds to a channel state information reference signal that is not precoded. The electronic device according to claim 1, wherein the condition that the composite channel obtained by weighting the predetermined plurality of channel features by using the plurality of weight parameters matches the actual channel is according to the The synthesized channel has the largest received power of the first reference signal. The electronic device of claim 1, wherein the processing circuit is further configured to: estimate an actual channel based on the first channel measurement, wherein the plurality of presets are utilized by the plurality of weight parameters The condition that the composite channel obtained by weight combining the channel characteristics matches the actual channel is that the synthesized channel has the greatest correlation with the estimated actual channel. The electronic device of claim 1, wherein the first reference signal transmitted by the target communication device is not precoded. The electronic device according to any one of claims 1 to 13, wherein the electronic device is implemented as a terminal device, the electronic device further comprising: a memory for storing the preset plurality of channel features; One or more antennas for transmitting signals to or receiving signals from the target communication device. A method performed in a terminal device, comprising: Performing a first channel measurement according to the first reference signal sent by the target communication device; Determining, according to the result of the first channel measurement, a plurality of weight parameters, so that the composite channel obtained by weighting the preset plurality of channel features by using the plurality of weight parameters matches the actual channel, wherein the preset The plurality of channel features are known by the terminal device and the target communication device; Generating feedback information indicating the plurality of weight parameters for transmission to the target communication device; Performing a second channel measurement according to a second reference signal transmitted by the target communication device, The second reference signal is sent by the target communication device via a composite channel obtained by weighting and combining the preset plurality of channel characteristics based on the plurality of weight parameters; A channel measurement report is generated based on the result of the second channel measurement for transmission to the target communication device. An electronic device for wireless communication, comprising a processing circuit, the processing circuit being configured to: Generating a first reference signal to be transmitted to the target communication device; And using a plurality of weight parameters indicated by the feedback information provided by the target communication device, weighting a plurality of preset channel characteristics to obtain a composite channel, wherein the plurality of weight parameters are the target communication device And determining, by using the first reference signal to perform the first channel measurement, that the composite channel obtained by performing weighted combination of the preset multiple channel features by using the multiple weight parameters matches the actual channel, where The preset plurality of channel features are well known to the electronic device and the target communication device. The electronic device of claim 16 wherein said processing circuit is further configured to: Generating a second reference signal to be transmitted to the target communication device, wherein the second reference signal is transmitted via the composite channel; The transport channel is configured based on a channel measurement report provided by the target communication device, wherein the channel measurement report is obtained by the target communication device performing second channel measurement by using the second reference signal. The electronic device according to claim 16, wherein the target communication device determines the plurality of weight parameters based on a preset codebook, wherein the preset codebook is a real digital book or a plurality of rotated codebooks. And the target communication device and the electronic device are well known. The electronic device of claim 18, wherein the feedback information comprises an index of a codeword in the codebook corresponding to each weight parameter. The electronic device of claim 18, wherein the processing circuit is further configured to: semi-statically configure the predetermined codebook and generate an indication of the updated codebook for the target communication device. The electronic device of claim 16, wherein the predetermined plurality of channel characteristics comprises a preset plurality of channel directions. The electronic device of claim 16, wherein the predetermined plurality of channels Features include a preset plurality of basis vectors. The electronic device of claim 21, wherein the preset plurality of channel directions correspond to a preset plurality of beams. The electronic device of claim 21, wherein the preset plurality of channel directions correspond to a preset plurality of precoding matrices. The electronic device of claim 16, wherein the first reference signal corresponds to a channel state information reference signal that is not precoded. The electronic device according to claim 16, wherein the condition that the composite channel obtained by weighting the predetermined plurality of channel features by using the plurality of weight parameters matches the actual channel is according to the The synthesized channel has the largest received power of the first reference signal. The electronic device of claim 16, wherein the first reference signal transmitted to the target communication device is not precoded. The electronic device according to any one of claims 16 to 27, wherein the electronic device is implemented as a network side device, the electronic device further comprising: a memory for storing the preset plurality of channel features; A plurality of antennas for transmitting signals to or receiving signals from the target communication device. A method performed in a network side device, comprising: Transmitting the first reference signal to the target communication device; And using a plurality of weight parameters provided by the target communication device to weight combine a preset plurality of channel features to obtain a composite channel, wherein the plurality of weight parameters are that the target communication device utilizes the first The reference signal is determined by performing the first channel measurement, so that the synthesized channel obtained by performing weighted combination of the preset plurality of channel features by using the plurality of weight parameters matches the actual channel, wherein the preset is more Channel characteristics are well known to the network side device and the target communication device; Transmitting a second reference signal to the target communication device via the composite channel; The transport channel is configured based on a channel measurement report provided by the target communication device, wherein the channel measurement report is obtained by the target communication device performing second channel measurement by using the second reference signal.

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