CN115102593A

CN115102593A - Method and device for selecting rank indication, baseband chip and terminal equipment

Info

Publication number: CN115102593A
Application number: CN202210663301.7A
Authority: CN
Inventors: 熊芳
Original assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Current assignee: Guangdong Oppo Mobile Telecommunications Corp Ltd
Priority date: 2022-06-13
Filing date: 2022-06-13
Publication date: 2022-09-23
Anticipated expiration: 2042-06-13
Also published as: CN115102593B

Abstract

A method, a device, a baseband chip and a terminal device for selecting rank indication are provided. The method comprises the following steps: determining mutual information corresponding to a plurality of rank indications; screening the plurality of rank indications according to mutual information corresponding to the plurality of rank indications to obtain a candidate set of the rank indications; and selecting the rank indication to be reported from the candidate set according to the rank indication in the candidate set and the precoding matrix indication corresponding to the rank indication in the candidate set. According to the method and the device, the candidate set is screened from the plurality of rank indications according to the mutual information corresponding to the plurality of rank indications, and then the rank indications in the screening set and the precoding matrix indications corresponding to the rank indications are traversed to select the rank indication to be reported, so that the complexity of calculation can be reduced on the premise of ensuring the selection precision of the rank indication.

Description

Method and device for selecting rank indication, baseband chip and terminal equipment

Technical Field

The present application relates to the field of communications technologies, and in particular, to a method and an apparatus for selecting rank indication, a baseband chip, and a terminal device.

Background

In the field of communications, MIMO technology is used in order to increase channel capacity. The MIMO technology performs precoding on one or more layers of data to be transmitted, and then transmits the data through multiple antennas. In different channel environments, in order to increase the channel capacity while ensuring the communication quality, the number of layers of communication data is typically dynamically adjusted. Taking LTE communication as an example, the number of layers of data is generally determined by Rank Indicator (RI). However, the current method for selecting rank indication has high computational complexity and cannot meet the communication requirement.

Disclosure of Invention

The application provides a method and a device for selecting rank indication, a baseband chip and terminal equipment. Various aspects of embodiments of the present application are described below.

In a first aspect, a method for selecting a rank indication is provided, including: determining mutual information corresponding to the plurality of rank indications; screening the plurality of rank indications according to mutual information corresponding to the plurality of rank indications to obtain a candidate set of the rank indications; and selecting the rank indication to be reported from the candidate set according to the rank indication in the candidate set and the precoding matrix indication corresponding to the rank indication in the candidate set.

In a second aspect, an apparatus for selecting a rank indication is provided, comprising: a determining module, configured to determine mutual information corresponding to each of the plurality of rank indications; the screening module is used for screening the plurality of rank indications according to the mutual information corresponding to the plurality of rank indications to obtain a candidate set of the rank indications; and the selection module is used for selecting the rank indication to be reported from the candidate set according to the rank indication in the candidate set and the precoding matrix indication corresponding to the rank indication in the candidate set.

In a third aspect, a baseband chip is provided, which includes a processor for calling a program from a memory, so that a device in which the chip is installed executes the method according to the first aspect.

In a fourth aspect, a chip is provided, which includes a processor for calling a program from a memory so that a device in which the chip is installed performs the method according to the first aspect.

In a fifth aspect, a terminal device is provided, comprising a memory for storing a program and a processor for calling the program in the memory to execute the method according to the first aspect.

In a sixth aspect, there is provided a computer readable storage medium having stored thereon executable code which, when executed, is capable of implementing a method as in the first aspect.

According to the method and the device, the candidate set is screened from the plurality of rank indications according to the mutual information corresponding to the plurality of rank indications, and then the rank indications in the screening set and the precoding matrix indications corresponding to the rank indications are traversed to select the rank indication to be reported, so that the complexity of calculation can be reduced on the premise of ensuring the selection precision of the rank indication.

Drawings

Fig. 1 is a wireless communication system to which an embodiment of the present application is applied.

Fig. 2 is a flowchart illustrating a method for selecting rank indication according to an embodiment of the present application.

Fig. 3 is a flowchart illustrating a possible implementation method of step S210 in fig. 2.

Fig. 4 is a flowchart of another method for selecting rank indication according to an embodiment of the present application.

Fig. 5 is a flowchart illustrating another method for selecting rank indication according to an embodiment of the present application

Fig. 6 is a schematic structural diagram of an apparatus for selecting a rank indication according to an embodiment of the present application.

Fig. 7 is a schematic structural diagram of a feedback device according to an embodiment of the present application.

Detailed Description

The technical solutions in the embodiments of the present application are clearly and completely described below, and it is obvious that the described embodiments are only a part of the embodiments of the present application, and not all embodiments.

Fig. 1 is a wireless communication system 100 to which an embodiment of the present application is applied. The wireless communication system 100 may include a network device 110 and a terminal device 120. Network device 110 may be a device that communicates with terminal device 120. Network device 110 may provide communication coverage for a particular geographic area and may communicate with terminal devices 120 located within that coverage area.

Fig. 1 exemplarily shows one network device and two terminals, and optionally, the wireless communication system 100 may include a plurality of network devices, and each network device may include other numbers of terminal devices within a coverage area, which is not limited in this embodiment of the present invention.

Optionally, the wireless communication system 100 may further include other network entities such as a network controller, a mobility management entity, and the like, which is not limited in this embodiment.

It should be understood that the technical solutions of the embodiments of the present application may be applied to various communication systems, for example: a fifth generation (5G) system or a New Radio (NR), a Long Term Evolution (LTE) system, a Frequency Division Duplex (FDD) system, a Time Division Duplex (TDD) system, and the like. The technical scheme provided by the application can also be applied to future communication systems, such as a sixth generation mobile communication system, a satellite communication system and the like.

The Terminal device in this embodiment may also be referred to as a User Equipment (UE), an access Terminal, a subscriber unit, a subscriber station, a Mobile Station (MS), a Mobile Terminal (MT), a remote station, a remote Terminal, a mobile device, a user Terminal, a wireless communication device, a user agent, or a user equipment. The terminal device in the embodiment of the present application may be a device providing voice and/or data connectivity to a user, and may be used for connecting people, things, and machines, such as a handheld device with a wireless connection function, a vehicle-mounted device, and the like. The terminal device in the embodiment of the present application may be a mobile phone (mobile phone), a tablet computer (Pad), a notebook computer, a palmtop computer, a Mobile Internet Device (MID), a wearable device, a Virtual Reality (VR) device, an Augmented Reality (AR) device, a wireless terminal in industrial control (industrial control), a wireless terminal in unmanned driving (self driving), a wireless terminal in remote surgery (remote medical supply), a wireless terminal in smart grid (smart grid), a wireless terminal in transportation safety (transportation safety), a wireless terminal in smart city (smart city), a wireless terminal in smart home (smart home), and the like.

It should be understood that all or part of the functionality of the communication device in the present application may also be implemented by software functions running on hardware, or by virtualized functions instantiated on a platform (e.g., a cloud platform).

In the communication field, the channel state information can be introduced during data transmission to fully utilize the channel condition to improve the communication efficiency. Taking the communication system shown in fig. 1 as an example, the network device 110 may transmit a Reference Signal (RS) for performing Channel measurement, such as a Cell-specific Reference Signal (CRS), a Demodulation Reference Signal (DMRS), a Channel State Information Reference Signal (CSI-RS), and the like, to the terminal device 120.

After receiving the reference signal sent by the network device 110, the terminal device 120 may process the reference signal to obtain information related to communication. For example, terminal device 120 may process the CSI-RS to obtain channel information between network device 110 and terminal device 120.

Terminal device 120 may feed back channel information to network device 110 for network device 110 to modify the communication configuration according to the current channel information, thereby improving communication performance (e.g., obtaining relatively better communication quality or relatively higher communication rate). For example, terminal device 120 may feed back Channel State Information (CSI) to network device 110 according to the CSI-RS, and network device 110 may select an appropriate communication parameter according to the CSI to communicate with terminal device 120. Terminal device 120 may report CSI over wideband or subband. Each subband may include a plurality of consecutive subcarriers. The wideband may contain a plurality of continuous or discontinuous sub-bands.

For systems that introduce massive mimo (massive mimo), network device 110 may transmit using different beams on different CSI-RS resources. In order to identify different CSI-RS resources, a CSI-RS Resource Indicator (CRI) is added. Terminal device 120 may select an optimal resource from a plurality of different CSI-RS resources, and report the CRI to network device 110. Based on the selected CSI-RS resources, terminal device 120 may calculate CSI for feeding back channel information. The specific content reported by the CSI may be selected according to the actual channel configuration. For example, the CSI may include a Channel Quality Indicator (CQI), a Precoding Matrix Indicator (PMI), a Rank Indicator (RI), and the like.

The RI may be used to indicate the number of layers of valid data. The number of layers of valid data affects the channel capacity. It is understood that the larger the number of layers of available data that can be transmitted, the larger the channel capacity. But the larger the number of active data layers, the greater the interference between data. Therefore, the accuracy of selecting the RI has a great influence on the efficiency and quality of communication. For example, if the current channel can support an RI of 2, if the selected RI is 1, the communication performance will be seriously lost (e.g., the provided communication rate is lower than the actually supportable communication rate). And if the selected RI is 3, it may result in the channel communication quality not meeting the requirement (e.g., result in the block error rate being higher than the block error rate threshold of the communication).

In order to ensure the accuracy of selecting RI, the related art provides a method for joint estimation of RI and PMI. The method selects a rank indication to be reported by combining the selection of RI and PMI and evaluating the maximum Mutual Information (MI) in the combination. The mutual information may reflect the statistical constraint degree between the input and output random variables, and may also represent the amount of information that may be transmitted by the current channel. The method is described in detail below.

First, an optional set of RIs is obtained according to Radio Resource Control (RRC) signaling, and the optional set may be represented as 1 ≦ R. Where R represents RI and R represents the maximum RI that the wireless communication system can support. For NR systems, RRC signaling may directly configure an optional set of RIs. The terminal device can read the optional set of RIs directly from the RRC signaling. The optional set includes a plurality of RIs. As an example, when the maximum RI that the wireless communication system can support is 4, the optional set of RIs can be {1,2,3,4 }.

Then, for each RI in the optional set of RIs, a set of PMIs corresponding to the current RI is determined, and an MI of the current RI is determined based on the set of PMIs corresponding to the current RI. E.g. from the above mentioned alternative set of RIs{1,2,3,4} select RI 2, and then determine the PMI set when RI is 2. In some embodiments, the set of PMIs may be represented in the form of a codebook. And finally, calculating MI corresponding to each PMI in the PMI set when RI is 2, and comparing the magnitude of MI corresponding to each PMI. Among them, the maximum MI can be determined as the MI under the current RI. Wherein MI under each PMI can be represented as MI _rk R represents a value of RI (e.g., 2), and k represents an index value of PMI (e.g., PMI value). And MI at this RI (i.e., the maximum MI described above) can be expressed as MI _r 。

And finally, traversing all RI in the selectable set of RI to determine MI under each RI in all RI, and comparing MI corresponding to different RI to obtain the maximum MI. The RI and PMI corresponding to the maximum MI are the optimal RI and PMI, and the RI corresponding to the maximum MI is the RI to be reported selected from the optional set of RIs. The optimal RI and PMI may be represented as:

{r _bset ，PMI _best }＝argmax(MI _r )0≤r＜R

as an example, repeating the above steps for RI of 2 for each of 1, 3, and 4 of the optional set {1,2,3,4} of RI above, yields MI for RI of 1,2,3, and 4, respectively ₁ 、MI ₂ 、MI ₃ 、MI ₄ . The MI ₁ 、MI ₂ 、MI ₃ 、MI ₄ The RI corresponding to the maximum value in the set of values is the RI to be reported.

Although the method for selecting RI to be reported by jointly estimating RI and PMI has better performance, it needs to traverse each RI in the optional set of RI obtained according to RRC signaling and traverse the PMI set corresponding to each RI, so as to calculate MI for each PMI in the PMI set. This results in a very large amount of computation, and may have a high requirement on the computing power of the terminal device, and the implementation is very complicated. Especially for NR or lte 9 mode, since the number of PMI sets may reach several hundreds or even thousands, for this case, the computational complexity involved in selecting the rank indication to be reported using the above method is higher, which is difficult to realize.

In view of this, the present application provides a method for selecting rank indication, which can reduce the computational complexity of selecting rank indication while ensuring the accuracy of selecting rank indication.

Fig. 2 is a flowchart illustrating a method for selecting rank indication according to an embodiment of the present application. As shown in fig. 2, the method for selecting a rank indication provided by the present application includes steps S210 to S230.

In step S210, MI corresponding to each of the plurality of RIs is determined.

The plurality of RIs in this embodiment may be RIs in the optional set of RIs obtained according to RRC signaling as described above. The MI corresponding to each of the plurality of RIs is an MI corresponding to each RI in the selectable set of RIs. It is understood that in the alternative set of RIs, the MI corresponding to each RI may be completely different or partially different, for example, may be expressed as a difference in MI value.

Determining the MI corresponding to each of the plurality of RIs in the embodiment of the present application may be understood as calculating the MI corresponding to each of the plurality of RIs by a method independent of PMI selection, that is, the calculation of the MI corresponding to each of the plurality of RIs is independent of PMI. For example, the MI corresponding to each of the plurality of RIs is a wideband MI corresponding to each of the plurality of RIs.

In step S220, the plurality of RIs are filtered according to their respective corresponding MI to obtain a candidate set of RIs.

The candidate set of RIs in the present embodiment may be understood as a set formed by some of the RIs selected from the above-mentioned RIs. The size of the screening set can be configured as desired.

The embodiment of the present application does not specifically limit the form of screening the multiple RIs according to their corresponding MI. For example, the screening may be performed according to the magnitude of the MI value corresponding to each of the plurality of RIs. Specifically, the MI values corresponding to each RI in the plurality of RIs are arranged in descending order, and then the RIs corresponding to the MI in the previous orders are screened out to form a candidate set of RIs. In this way, the size of the screening set can be configured by setting the specific bit order of the screening.

Alternatively, the distance of the RI and the MI value corresponding to each of the plurality of RIs may be combined for screening. Specifically, the MI values corresponding to each RI in the plurality of RIs are arranged in the order from large to small, the RI corresponding to the largest MI value is screened out from the MI values and added to the candidate set of RIs, and then a plurality of RI closer to the RI in the candidate set of RIs already added to the RI are screened out from the remaining plurality of RIs and added to the candidate set of RIs. In this way, the size of the screening set can be configured by setting the distance between the remaining part of the RIs of the screening and the RI corresponding to the maximum MI value.

In step S230, according to the RI in the candidate set and the PMI corresponding to the RI in the candidate set, the RI to be reported is selected from the candidate set.

The RI to be reported may be information for which CSI needs to be reported. When the CSI also needs to report other information, the RI to be reported may participate in the calculation of other information to be reported. For example, the RI to be reported may be used to calculate parameters such as PMI, CQI, PTI, and the like.

In this embodiment of the present application, selecting an RI to be reported from a candidate set according to an RI in the candidate set and a PMI corresponding to the RI in the candidate set may be understood as selecting an RI to be reported from the candidate set by combining the RI and the PMI, and by evaluating the largest MI in the combination.

Specifically, for each RI in the candidate set, a PMI set corresponding to the current RI is determined, and the MI of the current RI is determined based on the PMI set corresponding to the current RI. And finally, traversing all RI in the candidate set to determine MI under each RI in all RI, and comparing MI corresponding to different RI to obtain the maximum MI. The RI and PMI corresponding to the maximum MI are the optimal RI and PMI, and the RI corresponding to the maximum MI is the RI to be reported selected from the candidate set

By implementing the embodiment of the application, the mutual information can be used for screening a plurality of RI to form a candidate set, and then the RI in the candidate set and the corresponding PMI are used for joint estimation to select the RI to be reported. Therefore, the accuracy of RI in a screening set can be ensured, and the calculation amount in RI joint estimation can be reduced, so that the method reduces the calculation complexity on the premise of ensuring the precision of the selected RI to be reported.

As described above, the MI corresponding to each of the plurality of RIs may be a wideband MI corresponding to each of the plurality of RIs. The embodiment of the present application does not specifically limit the determining manner of the wideband MI corresponding to each of the plurality of RIs. For example, the wideband eigenvalue may be directly calculated by the wideband cross-correlation matrix, and then the wideband MI corresponding to each of the plurality of RIs may be determined based on the wideband eigenvalue.

Still alternatively, as shown in fig. 3, the step S210 may specifically include a step S211 and a step S212.

In step S211: the sub-band MI corresponding to each of the plurality of RIs is determined.

In step S212: and determining a broadband MI corresponding to each of the plurality of RI according to the sub-band MI corresponding to each of the plurality of RI.

The sub-bands and the wideband may be the aforementioned resources for reporting CSI, and the wideband may include a plurality of sub-bands. In the embodiment of the present application, determining the wideband MI corresponding to each of the plurality of RIs according to the sub-band MI corresponding to each of the plurality of RIs may be to accumulate the sub-band MI corresponding to each of the plurality of RI to obtain the corresponding wideband mutual information.

As an example, the specific calculation method may refer to the following formula:

where J denotes the number of the subband and J denotes the total number of subbands included in the wideband.

Because the implementation mode determines the sub-band MI corresponding to each of the plurality of RIs first and then determines the broadband MI corresponding to each of the plurality of RI based on the sub-band MI, the broadband MI can be guaranteed to include both the sub-band characteristic and the broadband characteristic, so that the characteristics of a channel are better reflected, the robustness of the calculation method of the MI corresponding to each of the plurality of RI is higher, and the accuracy of the finally selected RI to be reported is higher. It should be understood that the higher the selection accuracy of the RI to be reported, the better the communication performance of the wireless communication system. Therefore, the method provided by the embodiment of the application can ensure the communication performance and meet the communication requirement.

In this embodiment of the present application, a specific implementation manner of determining the sub-band MI corresponding to each of the plurality of RIs may be: and determining a sub-band characteristic value according to the sub-band channel cross-correlation matrix, and then determining a sub-band MI corresponding to each of the plurality of RIs according to the sub-band characteristic value.

The subband channel cross-correlation matrix may be understood as a channel estimation matrix, which may be a subband channel covariance matrix calculated after whitening the channel estimate.

The subband eigenvalue may be an eigenvalue obtained by decomposing an eigenvalue of the subband cross-correlation matrix. There may be many ways to determine the sub-band MI corresponding to each of the plurality of RIs according to the sub-band characteristic value. As an implementation manner, a Signal to Interference plus Noise Ratio (SINR) corresponding to each of the plurality of RIs may be determined according to the subband characteristic value, and then a subband MI corresponding to each of the plurality of RIs may be determined according to the SINR corresponding to each of the plurality of RIs. A specific implementation manner of determining the sub-band MI corresponding to each of the plurality of RIs according to the SINR corresponding to each of the plurality of RIs may be to substitute the SINR corresponding to each of the plurality of RI into a mapping function to calculate the sub-band MI corresponding to each of the plurality of RI.

It can be understood that in the subband channel cross-correlation matrix corresponding to different data layer numbers, the energy corresponding to each eigenvalue is different. For example, the energy corresponding to the eigenvalue at the data layer number of 1(RI of 1) is generally larger than the energy corresponding to the eigenvalue at each layer of data at the data layer number of 2(RI of 2). In view of this, before determining the snr corresponding to each of the plurality of RIs by using the eigenvalue, the subband eigenvalue may be normalized, and then the subband MI may be determined by using the mapping function according to the normalized subband eigenvalue. In this way, the calculation accuracy of MI can be effectively improved.

In the MIMO system, the more the number of effective data layers, the greater the interference between data. If the channel condition is determined incorrectly during the calculation, the wideband MI corresponding to each of the RIs may not be very different, and the selection of RI according to the result may cause jitter. That is, if in actual calculations the data disturbance considered is small, jitter problems will result.

For ease of understanding, the following is a brief description of dithering. Assuming that the current RI is 2, a new RI of 3 is calculated. However, the wideband mutual information obtained when RI is 3 is not much different from the wideband mutual information obtained when RI is 2. At this time, if the RI is switched to 3, poor communication quality (e.g., high block error rate) may result, and a jitter phenomenon may occur during communication.

In order to fully consider the interference, the problem that the calculation of the wideband MI corresponding to each of the plurality of RIs is different from the actual PMI, so that the effective data layer is not matched with the interference in the calculation process is avoided, and the finally selected RI is jittered.

In some embodiments, as shown in fig. 4, before step S220, the method may further include step S410.

In step S410, MI corresponding to each of the plurality of RIs is compensated according to the penalty factor.

The penalty factor may be understood as a compensation factor for making the calculated MI close to the MI of the real channel, wherein the larger the value of RI, the larger the penalty formed by the penalty factor. The penalty factor may be obtained in a number of ways. The penalty factor may be obtained, for example, by simulation. In order to improve the accuracy of the penalty factors, various channel conditions can be simulated, and the penalty factors under each channel condition can be obtained.

The specific implementation manner of compensating the MI corresponding to each of the plurality of RIs according to the penalty factor may be according to the following formula:

wherein MI is broadband mutual information before compensation,

for the compensated wideband mutual information, g is a penalty factor, and r is the RI corresponding to the current MI. The penalty factor g is less than 1.

By implementing the embodiment of the application, the penalty factors suitable for various channel conditions can be utilized to compensate the broadband mutual information, the compensation result does not need to depend on the accuracy of judging the channel conditions, but the RI switching is carried out only when higher RI can provide higher communication performance, the jitter phenomenon in communication is effectively avoided, the communication rate and the communication quality are considered, and the robustness of the RI selection result is effectively improved.

The method for selecting RI provided by the embodiments of the present application is exemplarily described in a specific embodiment with reference to fig. 5.

As shown in fig. 5, the method for selecting an RI may specifically include steps S510 to S590. It should be appreciated that multiple reference signals (e.g., multiple CSI-RSs) may be included in the wireless communication process. Different reference signals may correspond to different beam resources. The scheme provided by the embodiment of the application is a selection method of RI under a CSI-RS resource.

In step S510, whitening processing is performed on the subband channel estimate.

In step S520, a subband channel cross-correlation matrix is calculated, and specifically, the subband channel correlation matrix may be calculated using the following formula.

Wherein R is _sb (j) Representing the jth subband channel cross-correlation matrix. N is a radical of _j The number of sampling points of the jth sub-band is represented.

Representing the jth subband channel estimation result.

Representing the conjugate transpose of the jth subband channel estimation result.

In step S530, the feature value of the subband j is calculated. Specifically, the eigenvalue of the subband j may be obtained by using eigenvalue decomposition, and the calculation formula is as follows:

λ(j)＝eig(R _sb (j))

in step S540, SINR corresponding to each RI is calculated. The specific calculation formula is as follows:

where r represents the value of the rank indication. l represents each layer of data of the rank indicator r. SINR _r，l (j) And representing the signal-to-noise ratio of each layer of data corresponding to each rank indicator r of each subband j.

A normalization factor may be represented. By normalizing the signal-to-noise ratio corresponding to each layer of data, the calculation precision can be improved, and comparison between channels with different data layer numbers is facilitated.

In step S550, the sub-band MI corresponding to each RI in the optional set of RIs is calculated and the total sub-band MI corresponding to each RI in the optional set of RIs is calculated. The specific formula is as follows:

MI _r，l (j)＝f(SINR _r，l (j))

wherein MI _r，l (j) Representing the sub-band MI, f (×) represents the mapping function of the signal-to-noise ratio SINR to the sub-band MI.

Wherein MI _r (j) Representing the total MI of the sub-bands.

In step S560, the MI of the wideband corresponding to each RI in the selectable set of RIs is calculated. The calculation formula is as follows:

wherein MI _r Indicating a broadband MI. j denotes a subband. J denotes the total number of subbands.

In step S570, punishment processing is performed on the MI of the wideband corresponding to each RI in the optional set, and the RI is filtered based on the processed MI. The treated MI can be expressed as follows:

wherein the content of the first and second substances,

for processed wideband mutual information, MI _r (k) And g is a penalty factor and r is a rank indication corresponding to the current mutual information.

The process of screening RI based on the processed MI may specifically be: to the resource

Sorting and then selecting the maximum

The corresponding RI enters a candidate set of RI, and RI values near the RI which are lower than the MI value of the RI are selected into the candidate set. The candidate set size can be configured and the candidate set of the last selected RI can be defined as

With continued reference to fig. 5, in step S580, under the candidate set of RIs, the joint PMI calculates MI corresponding to each RI. For a specific method, reference may be made to the foregoing description, and MI corresponding to each RI in the candidate set may be represented as:

in step S590, an RI to be reported is selected according to the MI corresponding to each RI. The RI to be reported may be an RI corresponding to the largest MI among the MIs corresponding to the RIs. The RI to be reported may be represented as:

the scheme provided by the embodiment of the application can firstly utilize the sub-band channel cross-correlation matrix to calculate the eigenvalue, and pre-estimate MI under different rank indications (or rank), so as to primarily screen the optional set of RI, and reserve an effective RI set (namely a candidate set of RI). Traversing RI in the RI candidate set, and calculating MI by combining PMI to select RI to be reported from the candidate set. This method can ensure the accuracy of RI selection to ensure the performance of communication system. Meanwhile, the complexity of the calculation algorithm can be reduced to a certain degree.

Method embodiments of the present application are described in detail above in conjunction with fig. 1-5, and apparatus embodiments of the present application are described in detail below in conjunction with fig. 6 and 7. It is to be understood that the description of the method embodiments corresponds to the description of the apparatus embodiments, and therefore reference may be made to the method embodiments above for parts which are not described in detail.

Fig. 6 is a schematic structural diagram of an apparatus for selecting rank indication according to an embodiment of the present application. As shown in fig. 6, an apparatus 600 for selecting a rank indication may include a determining module 610, a screening module 620, and a selecting module 630.

The determining module 610 is configured to determine mutual information corresponding to a plurality of rank indications.

The screening module 620 is configured to screen the multiple rank indications according to mutual information corresponding to the multiple rank indications, so as to obtain a candidate set of rank indications.

The selecting module 630 is configured to select a rank indication to be reported from the candidate set according to the rank indication in the candidate set and a precoding matrix indication corresponding to the rank indication in the candidate set.

Optionally, the mutual information corresponding to the plurality of rank indications is wideband mutual information corresponding to the plurality of rank indications, and the determining module 610 is specifically configured to: determining subband mutual information corresponding to the plurality of rank indications respectively; and determining broadband mutual information corresponding to the plurality of rank indications according to the subband mutual information corresponding to the plurality of rank indications.

Optionally, the apparatus 600 further comprises a compensation module 640 for: before the rank indications are screened according to the mutual information corresponding to the rank indications, compensating the mutual information corresponding to the rank indications according to a penalty factor.

Optionally, the compensation module 640 is specifically configured to: according to

Compensating mutual information corresponding to each of the plurality of rank indications, wherein MI is wideband mutual information before compensation,

and g is a penalty factor and r is the rank indication corresponding to the current mutual information for the compensated broadband mutual information.

Optionally, the determining module 610 is configured to: determining a sub-band characteristic value according to the sub-band channel cross-correlation matrix; and determining sub-band mutual information corresponding to the plurality of rank indications according to the sub-band characteristic values.

Optionally, the determining module 610 is configured to: determining respective corresponding signal-to-noise ratios of the plurality of rank indications according to the sub-band characteristic values; and determining sub-band mutual information corresponding to the plurality of rank indications according to the signal-to-noise ratios corresponding to the plurality of rank indications.

Fig. 7 is a schematic configuration diagram of a feedback device according to an embodiment of the present application. The dashed lines in fig. 7 indicate that the unit or module is optional. The apparatus 700 may be used to implement the methods described in the method embodiments above. The apparatus 700 may be a baseband chip, a terminal device, or a network device.

The apparatus 700 may include one or more processors 710. The processor 710 may support the apparatus 700 to implement the methods described in the previous method embodiments. The processor 710 may be a general purpose processor or a special purpose processor. For example, the processor may be a Central Processing Unit (CPU). Alternatively, the processor may be another general-purpose processor, a Digital Signal Processor (DSP), an Application Specific Integrated Circuit (ASIC), an off-the-shelf programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The apparatus 700 may also include one or more memories 720. The memory 720 has stored thereon a program that can be executed by the processor 710 to cause the processor 710 to perform the methods described in the previous method embodiments. The memory 720 may be separate from the processor 710 or may be integrated into the processor 710.

The apparatus 700 may also include a transceiver 730. Processor 710 may communicate with other devices or chips through transceiver 730. For example, processor 710 may transmit and receive data to and from other devices or chips via transceiver 730.

The embodiment of the application also provides a baseband chip which comprises a processor. The baseband chip may be configured to call a program from a memory, so that a device in which the baseband chip is installed performs the method performed by the terminal device in the embodiments of the present application.

An embodiment of the present application further provides a computer-readable storage medium for storing a program. The computer-readable storage medium is applicable to the terminal device or the network device provided in the embodiments of the present application, and the program causes a computer to execute the method performed by the terminal device in the embodiments of the present application.

The embodiment of the application also provides a computer program product. The computer program product includes a program. The computer program product can be applied to the terminal device or the network device provided in the embodiments of the present application, and the program causes the computer to execute the method executed by the terminal device in the embodiments of the present application.

The embodiment of the application also provides a computer program. The computer program can be applied to the terminal device or the network device provided in the embodiments of the present application, and the computer program enables the computer to execute the method performed by the terminal device in the embodiments of the present application.

In the above embodiments, all or part of the implementation may be realized by software, hardware, firmware or any other combination. When implemented in software, may be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the procedures or functions described in accordance with the embodiments of the present application are generated in whole or in part. The computer may be a general purpose computer, a special purpose computer, a network of computers, or other programmable device. The computer instructions can be stored in a computer readable storage medium or transmitted from one computer readable storage medium to another computer readable storage medium, for example, the computer instructions can be transmitted from one website, computer, server, or data center to another website, computer, server, or data center via wired (e.g., coaxial cable, fiber optic, Digital Subscriber Line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) means. The computer-readable storage medium can be any available medium that can be accessed by a computer or a data storage device, such as a server, a data center, etc., that is integrated into one or more available media. The usable medium may be a magnetic medium (e.g., floppy Disk, hard Disk, magnetic tape), an optical medium (e.g., Digital Video Disk (DVD)), or a semiconductor medium (e.g., Solid State Disk (SSD)), among others.

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

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

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

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

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

Claims

1. A method of selecting a rank indication, comprising:

determining mutual information corresponding to a plurality of rank indications;

screening the plurality of rank indications according to mutual information corresponding to the plurality of rank indications to obtain a candidate set of the rank indications;

and selecting the rank indication to be reported from the candidate set according to the rank indication in the candidate set and the precoding matrix indication corresponding to the rank indication in the candidate set.

2. The method of claim 1, wherein the mutual information corresponding to the plurality of rank indications is wideband mutual information corresponding to the plurality of rank indications,

the determining mutual information corresponding to the plurality of rank indications comprises:

determining subband mutual information corresponding to the plurality of rank indications respectively;

and determining broadband mutual information corresponding to the plurality of rank indications according to the subband mutual information corresponding to the plurality of rank indications.

3. The method of claim 2, wherein before the screening the rank indications according to mutual information corresponding to the rank indications, the method further comprises:

and compensating the mutual information corresponding to the plurality of rank indications according to the penalty factor.

4. The method of claim 3, wherein the compensating for the mutual information corresponding to each of the plurality of rank indications according to a penalty factor comprises:

according to

for the compensated broadband mutual information, g is a penalty factor, and r is a rank indication corresponding to the current mutual information.

5. The method of claim 2, wherein the determining the subband mutual information corresponding to each of the plurality of rank indications comprises:

determining a sub-band characteristic value according to the sub-band channel cross-correlation matrix;

and determining sub-band mutual information corresponding to the plurality of rank indications according to the sub-band characteristic values.

6. The method of claim 5, wherein the determining the subband mutual information corresponding to each of the plurality of rank indications according to the subband characteristic value comprises:

determining respective corresponding signal-to-noise ratios of the plurality of rank indications according to the sub-band characteristic values;

and determining sub-band mutual information corresponding to the plurality of rank indications according to the signal-to-noise ratios corresponding to the plurality of rank indications.

7. An apparatus for selecting a rank indication, comprising:

a determining module, configured to determine mutual information corresponding to each of the plurality of rank indications;

the screening module is used for screening the plurality of rank indications according to the mutual information corresponding to the plurality of rank indications to obtain a candidate set of the rank indications;

and the selection module is used for selecting the rank indication to be reported from the candidate set according to the rank indication in the candidate set and the precoding matrix indication corresponding to the rank indication in the candidate set.

8. The apparatus of claim 7, wherein the respective mutual information of the plurality of rank indications is respective wideband mutual information of the plurality of rank indications, and wherein the determining module is configured to:

9. The apparatus of claim 8, further comprising a compensation module to: before the rank indications are screened according to the mutual information corresponding to the rank indications, compensating the mutual information corresponding to the rank indications according to a penalty factor.

10. The apparatus of claim 9, wherein the compensation module is configured to: according to

11. The apparatus of claim 8, wherein the determining module is configured to:

12. The apparatus of claim 11, wherein the determining module is configured to:

13. A baseband chip comprising a processor for calling a program from a memory to cause a device in which the baseband chip is installed to perform the method of any one of claims 1 to 6.

14. A terminal device comprising a memory for storing a program and a processor for invoking the program in the memory for performing the method of any one of claims 1-6.