CN102833033A - Channel state information feedback method, device and system - Google Patents
Channel state information feedback method, device and system Download PDFInfo
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Abstract
The invention discloses a channel state information feedback method, a device and a system. The method comprises equipment at the receiving end determining the channel state information feedback rate; the equipment at the receiving end acquiring CI (codebook set index) corresponding to the feedback rate, and selecting PMI (pre-coded matrix index) from the CI corresponding to the feedback rate; and the equipment at the receiving end transmitting PMI and CI to equipment at the transmitting end. The channel state information feedback method provided by the invention can improve the accuracy of CSI (channel state information) obtained by the equipment at the transmitting end while keeping low feedback overhead.
Description
Technical field
The present invention relates to the communications field, in particular to a kind of feedback method of channel status information, Apparatus and system.
Background technology
At present, people to radio communication service type and quality require increasingly high.In order to satisfy the requirement of wireless system capacity and high speed data transfers, under the more and more rare background of Radio Resource, improve the wireless frequency spectrum utilance and seem particularly important for system of broadband wireless communication with the multipath fading that overcomes wireless channel.
In the new generation of wireless communication system, for satisfying the requirement for the capability of wireless communication system and the availability of frequency spectrum, new wireless communication technology constantly is introduced into.Wherein, Multiple-input and multiple-output (Multiple Input Multiple Output; Abbreviate MIMO as) technology and OFDM (Orthogonal Frequency Division Multiplexing; Abbreviating OFDM as) technology etc. occurs in succession, can improve system spectral efficiency effectively and overcome problem such as channel selectivity decline, receives extensive concern and further investigation.
Be the performance gain of realizing that these are technological,, need know downlink channel condition information (Channel State Information abbreviates CSI as) generally at transmitting end equipment.And utilize CSI to do preliminary treatment according to channel characteristics to transmitting, and make signal be easy to receive and demodulation at receiving device, improve message pick-up quality and transmission rate.But because descending CSI can not directly obtain at transmitting end equipment; Especially frequency division multiplexing (Frequency Division Duplexing; Abbreviate FDD as) system, because the up-downgoing channel uses different frequencies, the CSI of down channel can only pass to transmitting end equipment through the mode of feedback.Therefore, channel information at first need record (for example, using methods such as pilot tone estimation) at receiving device, then the channel information that obtains is quantized, and is last, gives transmitting end equipment with quantizing later feedback of channel information.Obviously, quantified precision is high more, and the descending CSI that transmitting end equipment obtained is accurate more, helps improving systematic function more.But,, make when feedback takies least resource that transmitting end equipment can access comparatively accurate CSI information because feedback information need take the resource (frequency, time) of system so be necessary to study and design the quantification and the feedback method of channel information.
At new generation of wireless communication system Long Term Evolution (Long Term Evolution; Abbreviate LTE as) and senior Long Term Evolution (Long Term Evolution-Advanced; Abbreviate LTE-A as) in, the feedback based on precoding codebook is carried out some researchs, but only be provided with a cover code book under present a kind of transmitting antenna port arrangement; It is the feedback information volume that has only a kind of fixed size under a kind of transmitting antenna port arrangement; This mechanism can cause the unnecessary spending waste again in some cases in the accuracy that can limit CSI that transmitting end equipment obtains in some cases unavoidably, lacks flexibility.Therefore, how the size of the feedback information volume of channel information is set, makes feedback overhead try one's best and guarantee the accuracy of CSI that transmitting end equipment obtains little the time, the flexibility that improves feedback mechanism is worth further and studies.
For convenience, the several notions in the correlation technique are provided below:
Open-loop capacity: when having no feedback CSI, transmitting end equipment is taked the constant power emission for all signals, and at this moment, the system's average size that is obtained is called open-loop capacity, is expressed as C
Open
Closed-loop capacity: suppose that transmitting end equipment knows descending channel information fully, transmitting end equipment can accurately be adjusted the power division that transmits, thereby the system's average size that reaches is called closed-loop capacity, is expressed as C
ClosedObviously, closed-loop capacity is the maximum of power system capacity.
Feedback capacity: through the mode of feedback, use the limited feedback amount of information, make the power division that transmitting end equipment can transmit according to the feedback channel information that quantizes to transmitting end equipment feeding back downlink CSI.At this moment, the channel capacity that obtains is called feedback capacity, is expressed as C
Feedback
Summary of the invention
Main purpose of the present invention is to provide a kind of feedback scheme of channel condition information, to solve at least one in can not taking into account the problem that the CSI accuracy is high, the feedback mechanism flexibility is relatively poor that feedback overhead is little and transmitting end equipment is obtained in the correlation technique at least.
According to an aspect of the present invention, a kind of feedback method of channel status information is provided, has comprised: receiving device is confirmed the feedback velocity of channel condition information; Receiving device obtains the corresponding CI of feedback velocity, and from the corresponding code book set of feedback velocity, selects PMI; Receiving device sends to transmitting end equipment with PMI and CI.
Preferably, after receiving device sent to transmitting end equipment with PMI and CI, said method also comprised: transmitting end equipment obtains the pre-coding matrix of PMI indication from the code book set of CI indication, and uses pre-coding matrix to carry out the transmission of data.
Preferably; Before receiving device obtains the corresponding CI of feedback velocity; Said method also comprises: for every kind of antenna port number configuration of transmitting end equipment, transmitting end equipment and receiving device are preserved one or more sets public code book set, wherein; Different code book set are corresponding to different CI, and different code books is gathered corresponding different feedback velocity scopes.
Preferably, comprise this code book in every cover code book set and gather a plurality of pre-coding matrixes under the antenna port number configuration of corresponding transmitting end equipment.
Preferably, before receiving device obtained the corresponding code book index of set CI of feedback velocity, said method also comprised: receiving device is preserved the mapping table between feedback velocity scope and the set of each code book.
Preferably, receiving device confirms that the feedback velocity of channel condition information comprises: receiving device is set up the corresponding relation between feedback velocity and the feedback capacity according to the channel condition information that obtains; Receiving device is confirmed the lower bound of feedback velocity according to feedback capacity and open-loop capacity, confirms the upper bound of feedback velocity according to feedback capacity and closed-loop capacity, and confirms that between the upper bound and lower bound a feedback velocity is as actual feedback speed.
Preferably, receiving device is confirmed actual feedback speed through predetermined threshold is set, and wherein, predetermined threshold is used to set up the relation between feedback capacity and the closed-loop capacity.
Preferably; Receiving device confirms that through predetermined threshold is set actual feedback speed comprises: receiving device is measured the upper bound of the different pairing feedback velocity of predetermined threshold under the different signal to noise ratios; Obtain optimum feedback velocity; Wherein, optimum feedback velocity is the value of considering simultaneously near the upper bound of the feedback velocity of the pairing specific predetermined threshold of closed-loop capacity and minimum feedback expense; Receiving device confirms that optimum feedback velocity is an actual feedback speed.
Preferably, receiving device obtains optimum feedback velocity and also comprises: when having correlation between the state of feedback channel, and receiving device periodic feedback mechanism feeding back channel state information; Receiving device obtains the optimum feedback velocity in this cycle through the average feedback capacity of maximize channel in certain cycle.
Preferably; Above-mentioned periodic feedback mechanism does; The quantitative information of a channel condition information of every a plurality of Resource Block feedbacks; Wherein, quantitative information is the quantitative information of the channel condition information that estimation obtains on receiving device first Resource Block in a plurality of Resource Block, keeps fixing resource in each Resource Block in a plurality of Resource Block and is used for feeding back channel state information.
Preferably, it is characterized in that feedback velocity needs the size of feedack amount for after the channel condition information of channel estimating gained is quantized.
According to a further aspect in the invention, a kind of feedback device of channel condition information is provided, has comprised: determination module is used for confirming the feedback velocity of channel condition information; Acquisition module is used to obtain the corresponding CI of feedback velocity; Select module, be used for selecting PMI from the corresponding code book set of feedback velocity; Sending module is used for PMI and CI are sent to transmitting end equipment.
According to another aspect of the invention; A kind of reponse system of channel condition information is provided, has comprised: receiving device and transmitting end equipment, wherein; Receiving device comprises determination module, acquisition module, selection module and sending module; Transmitting end equipment comprises: receiver module, obtain module and transmitter module, determination module is used for confirming the feedback velocity of channel condition information; Acquisition module is used to obtain the corresponding CI of feedback velocity; Select module, be used for selecting PMI from the corresponding code book set of feedback velocity; Sending module is used for PMI and CI are sent to transmitting end equipment; Receiver module is used to receive PMI and CI; Obtain module, be used for obtaining the pre-coding matrix of PMI indication from the code book set of CI indication; Transmitter module is used to use pre-coding matrix to carry out the transmission of data.
Through the present invention; Adopt receiving device CI and PMI to be sent to the mode of transmitting end equipment; Solved and to have taken into account high, the relatively poor problem of feedback mechanism flexibility of the little CSI accuracy that is obtained with transmitting end equipment of feedback overhead in the correlation technique, and then reached when keeping feedback overhead little and improved the CSI accuracy that transmitting end equipment obtained and the effect of feedback mechanism flexibly is provided.
Description of drawings
Accompanying drawing described herein is used to provide further understanding of the present invention, constitutes the application's a part, and illustrative examples of the present invention and explanation thereof are used to explain the present invention, do not constitute improper qualification of the present invention.In the accompanying drawings:
Fig. 1 is the flow chart according to the feedback method of channel status information of the embodiment of the invention;
Fig. 2 is the sketch map according to the wireless feedback communication system of the embodiment of the invention;
Fig. 3 is the sketch map of the feedback arrangement in the embodiment of the invention four;
Fig. 4 is the structured flowchart according to the feedback device of the channel condition information of the embodiment of the invention;
Fig. 5 is the structured flowchart according to the reponse system of the channel condition information of the embodiment of the invention.
Embodiment
Below in conjunction with accompanying drawing and embodiment the present invention is elaborated.
Embodiment one
The embodiment of the invention provides a kind of feedback method of channel status information, and Fig. 1 is the flow chart according to the feedback method of channel status information of the embodiment of the invention, and is as shown in Figure 1, and this method comprises:
Step S102, receiving device confirm the feedback velocity of channel condition information;
Step S104; Receiving device obtains corresponding code book index of set (the Codebook Index of feedback velocity; Abbreviate CI as), and from the corresponding code book set of feedback velocity, select pre-coding matrix index (Precoding Matrix Indication abbreviates PMI as);
Step S106, receiving device sends to transmitting end equipment with PMI and CI.
In correlation technique, receiving device only feeds back PMI and gives transmitting end equipment, like this; Though can keep a less feedback overhead,, the precision of the CSI of feedback is not high; Present embodiment all feeds back to transmitting end equipment with CI and RMI; When keeping a less feedback overhead, can make transmitting end equipment obtain the CSI of a degree of precision, thereby a kind of feedback mechanism comparatively flexibly is provided.
Preferably, after step S106, transmitting end equipment can obtain the pre-coding matrix of this PMI indication from the code book set of this CI indication, and uses this pre-coding matrix to carry out the transmission of data.This embodiment makes transmitting end equipment can adopt suitable pre-coding matrix to send data.
In a preferred implementation of the embodiment of the invention; Before step S104; Can carry out following operation: for every kind of antenna port number configuration of transmitting end equipment, transmitting end equipment and receiving device are all preserved one or more sets public code book set, wherein; Different code book set are corresponding to different CI, and different code books is gathered corresponding different feedback velocity scopes.Among this embodiment, all preserve corresponding code book set in each equipment, therefore, only need to transmit appropriate C I, the code book that both sides' equipment can need use alternately.
Wherein, comprise this code book in every cover code book set and gather a plurality of pre-coding matrixes under the antenna port number configuration of corresponding transmitting end equipment.
Preferably, before step S104, receiving device can also be preserved the mapping table between feedback velocity scope and the set of each code book.Among this embodiment, receiving device can obtain the corresponding CI of feedback velocity through the mode of tabling look-up, so this embodiment has the simple advantage of realization.
Step S102 can adopt multiple implementation, can solve the technical problem that the application will solve.Only a kind of preferred implementation of step S102 is described below.Receiving device is set up the corresponding relation between feedback velocity and the feedback capacity according to the channel condition information that obtains; Then, receiving device is confirmed the lower bound of feedback velocity according to feedback capacity and open-loop capacity, confirms the upper bound of feedback velocity to confirm between this upper bound and this lower bound that again a feedback velocity is as actual feedback speed according to feedback capacity and closed-loop capacity.This embodiment provides a kind of method of definite feedback velocity, through this method, can obtain a suitable feedback velocity.
Preferably, receiving device can be confirmed actual feedback speed through predetermined threshold is set, and wherein, predetermined threshold is used to set up the relation between feedback capacity and the closed-loop capacity.Particularly; Receiving device confirms that through predetermined threshold is set actual feedback speed comprises: receiving device is measured the upper bound of the different pairing feedback velocity of predetermined threshold under the different signal to noise ratios; Obtain optimum feedback velocity; Wherein, optimum feedback velocity is the value of considering simultaneously near the upper bound of the feedback velocity of the pairing specific predetermined threshold of closed-loop capacity and minimum feedback expense; Then, receiving device confirms that optimum feedback velocity is an actual feedback speed.This embodiment introduces different signal to noise ratios and different predetermined thresholds, adds up optimum feedback velocity through measuring, thereby makes the feedback velocity that obtains more can satisfy actual needs.
Wherein, receiving device obtains optimum feedback velocity and can also comprise: when having correlation between the state of feedback channel, and receiving device periodic feedback mechanism feeding back channel state information; Receiving device obtains the optimum feedback velocity in this cycle through the average feedback capacity of maximize channel in certain cycle.Wherein, Periodic feedback mechanism does; The quantitative information of a channel condition information of every a plurality of Resource Block feedbacks; Wherein, quantitative information is the quantitative information of the channel condition information that estimation obtains on receiving device first Resource Block in a plurality of Resource Block, keeps fixing resource in each Resource Block in a plurality of Resource Block and is used for feeding back channel state information.Through present embodiment, when between the state of feedback channel, having correlation, also can obtain an only optimum feedback velocity, thereby obtain a suitable feedback velocity.
Preferably, feedback velocity needs the size of feedack amount for after the channel condition information of channel estimating gained is quantized.This embodiment has carried out further explanation to feedback velocity.
Embodiment two
Present embodiment provides a kind of method for designing of feedback mechanism of channel condition information, makes feedback take few resource of trying one's best, and simultaneously, transmitting end equipment can obtain comparatively accurate CSI information.Implementation procedure in the face of present embodiment specifies down.
At first the wireless feedback communication system is described, Fig. 2 is that as shown in Figure 2, the flow process of this feedback comprises according to the sketch map of feedback information in the wireless feedback communication system of the embodiment of the invention:
S201, transmitting end equipment sends data or pilot tone;
S202 at receiving device estimating channel information H, and makes up code book, and H is quantized, and obtains corresponding code word;
S203 feeds back to transmitting end equipment with the code word of estimated channel matrix H;
S204, transmitting end equipment do user's power division or precoding according to the code word of the channel information H that receives.
The feedback method of channel status information that present embodiment provides comprises: receiving device is confirmed the feedback velocity of channel condition information, and its pairing CI is sent to transmitting end equipment; Receiving device is selected suitable PMI and it is fed back to transmitting end equipment from the pairing code book set of this feedback velocity; Transmitting end equipment takes out the indicated pre-coding matrix of PMI and carries out the transmission of data from the indicated code book of CI is gathered.Wherein, the feedback velocity of channel condition information is meant: the size that the channel condition information of certain channel estimating gained need later to be quantized the feedack amount.
Every kind of antenna port configuration for transmitting end equipment; Transmitting end equipment and receiving device all have one or more sets publicly-owned code book set; Wherein, the corresponding different code book index of set of different code book set, the corresponding different feedback velocity scope of different code book set.Comprise a plurality of pre-coding matrixes of the corresponding transmitting end equipment antenna port number of institute under disposing in the set of every cover code book.
Receiving device also has the mapping table between feedback velocity scope and the set of each code book.
Wherein, Above-mentioned receiving device confirms that the method for the feedback velocity of channel condition information comprises: receiving device is set up the relation between feedback velocity and the feedback capacity according to the channel condition information that is obtained; And, obtain the lower bound of feedback velocity according to the relation of feedback capacity and open-loop capacity, and according to the relation of feedback capacity and closed-loop capacity; Obtain the upper bound of feedback velocity, actual feedback speed is between determined bound.
The confirming of actual feedback speed sets up through certain threshold value is set that relation between feedback capacity and the closed-loop capacity obtains; Specifically comprise: receiving device is being measured dividing value on the pairing feedback velocity of the different threshold values of statistics under the different signal to noise ratios; Obtaining the optimum feedback velocity under the different signal to noise ratios, this optimum feedback velocity is for considered the last dividing value near the feedback velocity under closed-loop capacity and the pairing specified threshold of minimum feedback expense simultaneously.
Preferably, when having correlation between the feedback channel state, receiving device through the average feedback capacity of maximize channel in certain cycle, obtains the feedback velocity of the optimum in this cycle according to periodic feedback mechanism feeding back channel state information.Wherein, periodic feedback mechanism is meant: every several Resource Block feedback is the quantitative information of the estimated channel condition information that obtains of receiving device on first Resource Block wherein once, wherein reserves fixing limited bit number in each Resource Block and uses as feedback.
Present embodiment has provided a kind of method for designing of feedback mechanism of channel condition information; This method is through being provided with the set of many cover code books at transmitting end equipment and receiving device; Confirm the code book set of the optimum that institute will use and the code book in the set of this code book with optimum feedback velocity, make the try one's best accuracy of the assurance channel condition information that transmitting end equipment obtained little time of receiving device feedback overhead.
Embodiment three
Present embodiment is the further optimization to embodiment one, and a kind of definite method of feedback velocity is provided, and this method may further comprise the steps.
Step 1 obtains open-loop capacity.For many antennas (MIMO) system, do not having under the condition of descending channel information, transmitting end equipment carries out constant power to the test signal of every antenna emission and distributes (gross power is fixed in system).Receiving device obtains channel information, and according to the open-loop capacity of Shannon channel theorem computing system.
Step 2 obtains closed-loop capacity.Receiving device obtains channel information, and the hypothesis transmitting end equipment knows same channel information, and transmitting end equipment can carry out power division according to channel information, and receiving device utilizes Shannon channel theorem to calculate closed-loop capacity.
Step 3 obtains feedback capacity.Set up the relation between feedback velocity and the feedback capacity, receiving device utilizes Shannon channel theorem to calculate feedback capacity.Its detailed process is following:
1) be N for the transmitting end equipment antenna number
t, and the receiving device antenna number be N
rSystem, suppose that CSI and the distortion of real channel information of feedback is D, the minimum feedback speed of then utilizing information source rate distortion theorem in the communication theory can obtain correspondence is:
Wherein, the gap between the channel information
of
and expression real channel information H and feedback;
representes receiving device channel variance (be appreciated that and be channel energy).The meaning of rate distortion function is: given distortion restriction, the percent of pass distortion function can calculate, corresponding required number of bits of feedback.Can obtain the channel information distortion size that feedback velocity R brings according to following formula is:
2) receiving device obtains real channel information H; Utilize channel information distortion value D; In actual channel information, add and answer Gaussian noise E (is that noise variance generates random noise with D) at random, thus the channel information that obtains feeding back
3) utilize
and H; In the feedback capacity of subscriber equipment (User Equipment abbreviates UE as) end according to Shannon channel theorem computing system.
Step 4 designs the floor value of effective feedback velocity.It is poor excessively that feedback velocity is crossed the low feedback CSI precision that may cause, thereby cause transmitting end equipment to distribute the power failure according to coarse CSI, and the power system capacity that obtains is lower than open-loop capacity, and at this moment, we there is no need feedback channel information.Therefore in real system, through step 1 and step 3, obtain the poor of open-loop capacity and feedback capacity, be on duty when being zero, the pairing feedback velocity of feedback capacity is lower bound R
Loewr, be formulated as:
R
lower＝arg{C
feedback-C
open≡0}
Wherein, R
Lower=arg{C
Feedback-C
Open≡ 0} representes R
LowerFor working as C
Feedback-C
OpenThe value of R when ≡ 0 sets up.
Step 5 designs the last dividing value of effective feedback velocity.In the actual feedback system, feedback velocity is big more, and is then accurate more at the channel information of transmitting end equipment acquisition, and therefore, the system feedback capacity of acquisition is also just big more.When feedback capacity during near closed-loop capacity, along with the increase of feedback velocity, the feedback capacity increase becomes slowly, even nonsensical, therefore, the last dividing value of effective feedback velocity need be set.Obtain the closed-loop capacity and the feedback capacity of channel respectively through step 2 and step 3, calculate the relative capacity loss of feedback capacity in view of the above: Δ C=(C with respect to closed-loop capacity
Closed-C
Feedback)/C
ClosedWhen the relative loss of feedback capacity during less than certain threshold value, increase feedback velocity not only power system capacity obviously do not increase, also increased overhead.At this moment, the corresponding feedback velocity value of feedback capacity is:
R
upper(β)＝arg{ΔC≡β}
Wherein, β is the relative capacity loss thresholding of setting according to system requirements.
Step 6 is confirmed actual feedback speed.In a last step, dividing value on the corresponding different feedback velocity of different threshold value.Receiving device is being measured dividing value on the pairing feedback velocity of the different threshold values of statistics under the different signal to noise ratios; To obtain the optimum feedback velocity under the different signal to noise ratios, this optimum feedback velocity is for to have considered near dividing value on the feedback velocity under closed-loop capacity and the pairing a certain threshold value of minimum feedback expense simultaneously.
Embodiment four
Present embodiment is the further improvement to embodiment one, and this embodiment provides definite method of another kind of feedback velocity, is elaborated in the face of showing process in fact down.
Because in the practical application, the interchannel that each Resource Block is corresponding is not independently, but life period correlation.Therefore, and do not require that the CSI on each Resource Block feeds back, can be within the scope that error is allowed, several Resource Block feed back once, that is, and CSI of every several Resource Block feedbacks.Wherein, reserve fixing limited bit number in each Resource Block and use as feedback, this way is called periodic feedback mechanism.
In this periodic feedback mechanism, feedback velocity is big more, and the channel information that feedback obtains is just accurate more, and this can increase the feedback capacity of system; But because the restriction of the feedback capacity on each piece, along with number of bits of feedback increases, the feedback cycle that needs also strengthens, and makes temporal correlation reduce, thereby causes feedback capacity to reduce.Therefore, under the condition of periodic feedback, need the suitable feedback velocity of design to make that the simultaneity factor capacity of reduction feedback overhead can be maximum.To this problem, present embodiment has provided a kind of method for designing of optimum feedback velocity.Feedback arrangement is as shown in Figure 3.
Receiving device feeds back to transmitting end equipment to first channel parameter in each cycle, and transmitting end equipment carries out power division according to channel information to transmitting.Its process is following:
Receiving device obtains channel information.Receiving device is through estimate obtaining descending channel information, and each first channel information in cycle is quantized.
Through feedback channel feeding back downlink CSI.It is C that the feedback information of reserving in each Resource Block is set
FbBit.Receiving device is distributed in next Resource Block internal feedback with the descending channel information that quantizes.Therefore; When needs feedack amount is the R bit; The feedback cycle that needs is:
wherein,
expression is greater than the smallest positive integral of x.
Set up the relation of feedback velocity and channel errors.For the transmitting end equipment antenna number is N
t, and the receiving device antenna number be N
rSystem, suppose that CSI and the distortion of real channel information of feedback is D, the minimum feedback speed of then utilizing information source rate distortion theorem in the communication theory can obtain correspondence should be:
Wherein, the gap between the channel information
of
and expression real channel information H and feedback;
representes receiving device channel variance (also be appreciated that and be channel energy).Can obtain the channel information distortion size that feedback velocity R brings according to following formula is:
Generate the quantification CSI of equivalence in the receiving device simulation.Utilize channel information distortion value D, in actual channel information, add at random again Gaussian noise E (is that noise variance generates random noise with D), thus the channel information that obtains feeding back
Utilize
and H, receiving device calculates the feedback capacity of each Resource Block according to Shannon channel theorem.
Feedback capacity to the whole cycle is averaged, and obtains the average feedback capacity C of channel
Erg:
Wherein, K indication cycle size, H (τ
i) represent that this cycle is interior and be quantized channel
Difference τ
iThe channel information of time.
representes first CSI constantly that each cycle is quantized.In the temporal correlation channel, along with τ
iIncrease, channel relevancy reduces, corresponding channel capacity reduces.
Can find out from top analysis; Under the limited situation of each piece feedback velocity; Increase along with feedback of channel information speed;
precision increases, and makes power system capacity rise.But bigger feedback of channel information rate requirement is in bigger feedback cycle
internal feedback; This makes that again channel relevancy reduces, and influences the capacity of whole system at last.Therefore, exist the feedback velocity can equilibrium feedback precision and these two factors of temporal correlation, make power system capacity reach optimum.
The acquisition process of optimum feedback velocity is described below.For different feedback velocities, test respectively, calculate the channel capacity that obtains, and definite optimal value, make pairing feedback velocity when the cycle, average feedback capacity was maximum, be optimum feedback velocity R
Optimal:
Utilize the method for designing of the optimum feedback velocity that proposes in the present embodiment, we can find the feedback velocity method for designing that makes that the cycle average size is maximum.
Embodiment five
Present embodiment provides a kind of feedback device of channel condition information, and this device can be used as receiving device and realizes the foregoing description one to four.Fig. 4 is the structured flowchart according to the feedback device of the channel condition information of the embodiment of the invention, and is as shown in Figure 4, and this device comprises: determination module 42 is used for confirming the feedback velocity of channel condition information; Acquisition module 44 is coupled to determination module 42, is used to obtain the corresponding CI of feedback velocity; Select module 46, be coupled to acquisition module 44, be used for selecting PMI from the corresponding code book set of feedback velocity; Sending module 48 is coupled to acquisition module 44 and selects module 46, is used for PMI and CI are sent to transmitting end equipment.
In correlation technique, receiving device only feeds back PMI and gives transmitting end equipment, like this; Though can keep a less feedback overhead,, the precision of the CSI that can not guarantee to feed back; Present embodiment all feeds back to transmitting end equipment with CI and RMI; When keeping a less feedback overhead, can make transmitting end equipment obtain the CSI of a degree of precision, thereby a kind of feedback mechanism flexibly is provided.
Determination module 42 can adopt multiple implementation, can solve the technical problem that the application will solve.Only a kind of preferred implementation of determination module 42 is described below.Determination module 42 comprises: obtain submodule, be used for setting up the corresponding relation between feedback velocity and the feedback capacity according to the channel condition information that obtains; Confirm submodule, be used for confirming the lower bound of feedback velocity, confirm the upper bound of feedback velocity to confirm between this upper bound and this lower bound that again a feedback velocity is as actual feedback speed according to feedback capacity and closed-loop capacity according to feedback capacity and open-loop capacity.This embodiment provides a kind of device of definite feedback velocity, and through this device, those skilled in the art can obtain a suitable feedback velocity.
Preferably, determination module 42 can be used for confirming actual feedback speed through predetermined threshold is set that wherein, predetermined threshold is used to set up the relation between feedback capacity and the closed-loop capacity.Particularly; Determination module 42 confirms that through predetermined threshold is set actual feedback speed comprises: receiving device is measured the upper bound of the different pairing feedback velocity of predetermined threshold under the different signal to noise ratios; Obtain optimum feedback velocity; Wherein, optimum feedback velocity is the value of considering simultaneously near the upper bound of the feedback velocity of the pairing specific predetermined threshold of closed-loop capacity and minimum feedback expense; Then, receiving device confirms that optimum feedback velocity is an actual feedback speed.This embodiment introduces different signal to noise ratios and different predetermined thresholds, adds up optimum feedback velocity through measuring, thereby makes the feedback velocity that obtains more can satisfy actual needs.
Wherein, determination module 42 can also be used for: when having correlation between the state of feedback channel, and receiving device periodic feedback mechanism feeding back channel state information; Receiving device obtains the optimum feedback velocity in this cycle through the average feedback capacity of maximize channel in certain cycle.Wherein, Periodic feedback mechanism does; The quantitative information of a channel condition information of every a plurality of Resource Block feedbacks; Wherein, quantitative information is the quantitative information of the channel condition information that estimation obtains on receiving device first Resource Block in a plurality of Resource Block, keeps fixing resource in each Resource Block in a plurality of Resource Block and is used for feeding back channel state information.Through present embodiment, when between the state of feedback channel, having correlation, also can obtain an only optimum feedback velocity, thereby obtain a suitable feedback velocity.
Preferably, above-mentioned feedback velocity needs the size of feedack amount for after the channel condition information of channel estimating gained is quantized.This embodiment has carried out further explanation to feedback velocity.
Embodiment six
Present embodiment provides a kind of reponse system of channel condition information, and this system can realize the foregoing description one to four.Fig. 5 is the structured flowchart according to the reponse system of the channel condition information of the embodiment of the invention; As shown in Figure 5, this system comprises: receiving device 52 and transmitting end equipment 54, wherein; Receiving device 52 comprises determination module 42, acquisition module 44, selects module 46 and sending module 48; Transmitting end equipment 54 comprises: receiver module 542, obtain module 544 and transmitter module 546, determination module 42 is used for confirming the feedback velocity of channel condition information; Acquisition module 44 is coupled to determination module 42, is used to obtain the corresponding CI of feedback velocity; Select module 46, be coupled to acquisition module 44, be used for selecting PMI from the corresponding code book set of CI; Sending module 48 is coupled to acquisition module 44 and selects module 46, is used for PMI and CI are sent to transmitting end equipment; Receiver module 542 is used to receive PMI and CI; Obtain module 544, be coupled to receiver module 542, be used for obtaining the pre-coding matrix of PMI indication from the code book set of CI indication; Transmitter module 546 is coupled to and obtains module 544, is used to use pre-coding matrix to carry out the transmission of data.
In correlation technique, receiving device only feeds back PMI and gives transmitting end equipment, like this; Though can keep a less feedback overhead,, the precision of the CSI that can not guarantee to feed back; Present embodiment all feeds back to transmitting end equipment with CI and RMI; When keeping a less feedback overhead, can make transmitting end equipment obtain the CSI of a degree of precision, thereby a kind of feedback mechanism flexibly is provided.
Preferably; For every kind of antenna port number configuration of transmitting end equipment, transmitting end equipment 54 is all preserved one or more sets public code book set with receiving device 52, wherein; Different code book set are corresponding to different CI, and different code books is gathered corresponding different feedback velocity scopes.Among this embodiment, all preserve corresponding code book set in each equipment, therefore, only need to transmit appropriate C I, the code book that both sides' equipment can need use alternately.
Wherein, comprise this code book in every cover code book set and gather a plurality of pre-coding matrixes under the antenna port number configuration of corresponding transmitting end equipment.
Preferably, receiving device 52 can also be used to preserve the mapping table between feedback velocity scope and the set of each code book.Among this embodiment, receiving device 52 can obtain the corresponding CI of feedback velocity through the mode of tabling look-up, so this embodiment has the simple advantage of realization.
Determination module 42 can adopt multiple implementation, can solve the technical problem that the application will solve.Only a kind of preferred implementation of determination module 42 is described below.Determination module 42 comprises: obtain submodule, be used for setting up the corresponding relation between feedback velocity and the feedback capacity according to the channel condition information that obtains; Confirm submodule, be used for confirming the lower bound of feedback velocity, confirm the upper bound of feedback velocity to confirm between this upper bound and this lower bound that again a feedback velocity is as actual feedback speed according to feedback capacity and closed-loop capacity according to feedback capacity and open-loop capacity.This embodiment provides a kind of device of definite feedback velocity, and through this device, those skilled in the art can obtain a suitable feedback velocity.
Preferably, determination module 42 can be used for confirming actual feedback speed through predetermined threshold is set that wherein, predetermined threshold is used to set up the relation between feedback capacity and the closed-loop capacity.Particularly; Determination module 42 confirms that through predetermined threshold is set actual feedback speed comprises: receiving device is measured the upper bound of the different pairing feedback velocity of predetermined threshold under the different signal to noise ratios; Obtain optimum feedback velocity; Wherein, optimum feedback velocity is the value of considering simultaneously near the upper bound of the feedback velocity of the pairing specific predetermined threshold of closed-loop capacity and minimum feedback expense; Then, receiving device confirms that optimum feedback velocity is an actual feedback speed.This embodiment introduces different signal to noise ratios and different predetermined thresholds, adds up optimum feedback velocity through measuring, thereby makes the feedback velocity that obtains more can satisfy actual needs.
Wherein, determination module 42 can also be used for: when having correlation between the state of feedback channel, and receiving device periodic feedback mechanism feeding back channel state information; Receiving device obtains the optimum feedback velocity in this cycle through the average feedback capacity of maximize channel in certain cycle.Wherein, Periodic feedback mechanism does; The quantitative information of a channel condition information of every a plurality of Resource Block feedbacks; Wherein, quantitative information is the quantitative information of the channel condition information that estimation obtains on receiving device first Resource Block in a plurality of Resource Block, keeps fixing resource in each Resource Block in a plurality of Resource Block and is used for feeding back channel state information.Through present embodiment, when between the state of feedback channel, having correlation, also can obtain an only optimum feedback velocity, thereby obtain a suitable feedback velocity.
Preferably, above-mentioned feedback velocity needs the size of feedack amount for after the channel condition information of channel estimating gained is quantized.This embodiment has carried out further explanation to feedback velocity.
In another embodiment, a kind of feedback software of channel condition information is provided also, this software is used for carrying out the technical scheme that the foregoing description and preferred embodiment are described.
In another embodiment, a kind of storage medium is provided also, has stored the feedback software of above-mentioned channel condition information in this memory mechanism.
In sum; The present invention adopts receiving device CI and PMI to be sent to the mode of receiving device; Solved and to have taken into account the little high problem of CSI accuracy that is obtained with transmitting end equipment of feedback overhead in the correlation technique, and then reached the effect that when keeping feedback overhead little, has improved the CSI accuracy that transmitting end equipment obtained.
Obviously, it is apparent to those skilled in the art that above-mentioned each module of the present invention or each step can realize with the general calculation device; They can concentrate on the single calculation element; Perhaps be distributed on the network that a plurality of calculation element forms, alternatively, they can be realized with the executable program code of calculation element; Thereby; Can they be stored in the storage device and carry out, and in some cases, can carry out step shown or that describe with the order that is different from here by calculation element; Perhaps they are made into each integrated circuit modules respectively, perhaps a plurality of modules in them or step are made into the single integrated circuit module and realize.Like this, the present invention is not restricted to any specific hardware and software combination.
The above is merely the preferred embodiments of the present invention, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.All within spirit of the present invention and principle, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (13)
1. a feedback method of channel status information is characterized in that, comprising:
Receiving device is confirmed the feedback velocity of channel condition information;
Said receiving device obtains the corresponding code book index of set CI of said feedback velocity, and from the corresponding code book set of said feedback velocity, selects pre-coding matrix index PMI;
Said receiving device sends to transmitting end equipment with said PMI and said CI.
2. method according to claim 1 is characterized in that, after said receiving device sent to transmitting end equipment with said PMI and said CI, said method also comprised:
Said transmitting end equipment obtains the pre-coding matrix of said PMI indication from the code book set of said CI indication, and uses said pre-coding matrix to carry out the transmission of data.
3. method according to claim 2 is characterized in that, before said receiving device obtained the corresponding code book index of set CI of said feedback velocity, said method also comprised:
Every kind of antenna port number configuration for said transmitting end equipment; Said transmitting end equipment and said receiving device are preserved one or more sets public code book set; Wherein, different code book set are corresponding to different CI, and different code books is gathered corresponding different feedback velocity scopes.
4. method according to claim 3 is characterized in that, comprises this code book in the said code book set of every cover and gathers a plurality of pre-coding matrixes under the antenna port number configuration of corresponding said transmitting end equipment.
5. method according to claim 3 is characterized in that, before said receiving device obtained the corresponding code book index of set CI of said feedback velocity, said method also comprised:
Said receiving device is preserved the mapping table between feedback velocity scope and each the said code book set.
6. method according to claim 1 is characterized in that, said receiving device confirms that the feedback velocity of channel condition information comprises:
Said receiving device is set up the corresponding relation between feedback velocity and the feedback capacity according to the channel condition information that obtains;
Said receiving device is confirmed the lower bound of said feedback velocity according to said feedback capacity and open-loop capacity; Confirm the upper bound of said feedback velocity according to said feedback capacity and closed-loop capacity, and confirm that between the said upper bound and said lower bound a feedback velocity is as actual feedback speed.
7. method according to claim 6 is characterized in that, said receiving device is confirmed said actual feedback speed through predetermined threshold is set, and wherein, said predetermined threshold is used to set up the relation between said feedback capacity and the said closed-loop capacity.
8. method according to claim 7 is characterized in that, said receiving device confirms that through predetermined threshold is set said actual feedback speed comprises:
Said receiving device is measured the upper bound of the different pairing feedback velocity of said predetermined threshold under the different signal to noise ratios; Obtain optimum feedback velocity; Wherein, said optimum feedback velocity is the value of considering simultaneously near the upper bound of the feedback velocity of the pairing specific said predetermined threshold of said closed-loop capacity and minimum feedback expense;
Said receiving device confirms that said optimum feedback velocity is said actual feedback speed.
9. method according to claim 8 is characterized in that, said receiving device obtains optimum feedback velocity and also comprises:
When having correlation between the state of feedback channel, said receiving device periodic feedback mechanism feeds back said channel condition information;
Said receiving device obtains the said optimum feedback velocity in this cycle through the average feedback capacity of maximize channel in certain cycle.
10. method according to claim 9; It is characterized in that; Said periodic feedback mechanism is that every a plurality of Resource Block feed back the quantitative information of a channel condition information, wherein; Said quantitative information is the quantitative information of the channel condition information that estimation obtains on said receiving device first Resource Block in said a plurality of Resource Block, keeps fixing resource in each Resource Block in said a plurality of Resource Block and is used to feed back said channel condition information.
11., it is characterized in that said feedback velocity needs the size of feedack amount for after the channel condition information of channel estimating gained is quantized according to each described method in the claim 1 to 10.
12. the feedback device of a channel condition information is characterized in that, comprising:
Determination module is used for confirming the feedback velocity of channel condition information;
Acquisition module is used to obtain the corresponding code book index of set CI of said feedback velocity;
Select module, be used for selecting pre-coding matrix index PMI from the corresponding code book set of said feedback velocity;
Sending module is used for said PMI and said CI are sent to transmitting end equipment.
13. the reponse system of a channel condition information; It is characterized in that; Comprise: receiving device and transmitting end equipment, wherein, said receiving device comprises determination module, acquisition module, selection module and sending module; Said transmitting end equipment comprises: receiver module, acquisition module and transmitter module
Said determination module is used for confirming the feedback velocity of channel condition information;
Said acquisition module is used to obtain the corresponding code book index of set CI of said feedback velocity;
Said selection module is used for selecting pre-coding matrix index PMI from the corresponding code book set of said feedback velocity;
Said sending module is used for said PMI and said CI are sent to said transmitting end equipment;
Said receiver module is used to receive said PMI and said CI;
Said acquisition module is used for obtaining the pre-coding matrix that said PMI indicates from the code book set of said CI indication;
Said transmitter module is used to use said pre-coding matrix to carry out the transmission of data.
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| CN201110157720.5A CN102833033B (en) | 2011-06-13 | The feedback method of channel condition information, Apparatus and system |
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| Publication Number | Publication Date |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015024210A1 (en) * | 2013-08-21 | 2015-02-26 | 华为技术有限公司 | Method, apparatus and system for selecting precoding matrix indicator |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101286756A (en) * | 2008-05-29 | 2008-10-15 | 上海交通大学 | Method and device of space division multiple address system based on codebook of optimal quantization error |
| US20100091892A1 (en) * | 2008-10-10 | 2010-04-15 | Qualcomm Incorporated | Method and apparatus for channel feedback by multiple description coding in a wireless communication system |
| CN101771514A (en) * | 2010-02-12 | 2010-07-07 | 中兴通讯股份有限公司 | Multi-level feedback method of channel information and system thereof |
| CN102082639A (en) * | 2010-11-08 | 2011-06-01 | 大唐移动通信设备有限公司 | Channel state information transmitting method and equipment |
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101286756A (en) * | 2008-05-29 | 2008-10-15 | 上海交通大学 | Method and device of space division multiple address system based on codebook of optimal quantization error |
| US20100091892A1 (en) * | 2008-10-10 | 2010-04-15 | Qualcomm Incorporated | Method and apparatus for channel feedback by multiple description coding in a wireless communication system |
| CN101771514A (en) * | 2010-02-12 | 2010-07-07 | 中兴通讯股份有限公司 | Multi-level feedback method of channel information and system thereof |
| CN102082639A (en) * | 2010-11-08 | 2011-06-01 | 大唐移动通信设备有限公司 | Channel state information transmitting method and equipment |
Non-Patent Citations (2)
| Title |
|---|
| PANTECH&CURITEL: "Differential PMI Feedback for Overhead Reduction in LTE-A DL MIMO", 《3GPP TSG-RAN WG1 #58 R1-093453》, 28 August 2009 (2009-08-28) * |
| 孙宝玉 等: "基于信道质量干扰比量化准则的有限反馈波束形成", 《信号处理》, 31 October 2010 (2010-10-31) * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2015024210A1 (en) * | 2013-08-21 | 2015-02-26 | 华为技术有限公司 | Method, apparatus and system for selecting precoding matrix indicator |
| US9705577B2 (en) | 2013-08-21 | 2017-07-11 | Huawei Technologies Co., Ltd. | Method for selecting precoding matrix indication, apparatus and system |
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