CN106559167A

CN106559167A - A kind of method and device of link circuit self-adapting

Info

Publication number: CN106559167A
Application number: CN201510623918.6A
Authority: CN
Inventors: 朱莉; 鲍坤超; 严朝译; 胥恒
Original assignee: Huawei Technologies Co Ltd
Current assignee: Huawei Technologies Co Ltd
Priority date: 2015-09-25
Filing date: 2015-09-25
Publication date: 2017-04-05
Anticipated expiration: 2035-09-25
Also published as: CN106559167B; WO2017050213A1

Abstract

The invention discloses a kind of method and device of link circuit self-adapting, is related to communication technical field, invent for the inaccurate problems of the CQI for solving to report present in prior art.Wherein, the method includes：The terminal capacity report message that receive user equipment sends；The transmission mode statistics of the terminal capability possessed according to user equipment and the user equipment in the current statistic cycle, channel quality indicator (CQI) is sent to user equipment and reports instruction message, the CQI reports instruction message to be used to indicate that the user equipment reports CQI by the way of corresponding with the terminal capability and the statistics；MCS is carried out according to the CQI and user equipment of user equipment to report current transmission mode and selects rank.Present invention is mainly applied to during link circuit self-adapting.

Description

Link self-adaption method and device

Technical Field

The present invention relates to the field of communications technologies, and in particular, to a method and an apparatus for link adaptation.

Background

In cellular mobile communication systems, link adaptation techniques are typically employed to estimate the performance of the radio channel. The link adaptive technique refers to a behavior that a system adaptively adjusts a system transmission parameter according to currently acquired channel information so as to overcome or adapt to an influence caused by current channel change. Generally, the link adaptation technique, as shown in fig. 1, mainly includes the following three aspects: on the first hand, the current channel environment parameters are accurately and effectively acquired to carry out accurate channel estimation; selecting a channel indication parameter capable of accurately reflecting the channel condition; in a third aspect, transmission parameters are adjusted and feedback information is timely returned through a feedback channel. Generally, a Channel Quality Indicator (CQI) is used to represent the Quality of a current Channel, and the indicated Channel estimation is a value for obtaining the current CQI of the Channel. The link adaptation technology is realized on the basis of accurately acquiring the CQI. In the prior art, there are two methods for obtaining CQI, which are as follows:

firstly, the terminal measures a Signal-to-Interference plus noise ratio (SINR) based on a Cell-specific reference Signal (CRS), quantizes the SINR to obtain a CQI, and reports the CQI to the base station. The procedure of calculating SINR based on CRS may refer to the following equation (1):

wherein, RSRP_CRSRepresents a received power of the CRS; i is_nRepresenting interference of adjacent cells n to the CRS; n represents noise. In addition, I_nThe method specifically comprises the following steps: when the Physical Cell Identity (PCI) modulo 3 conflicts, only the interference of the CRS of the adjacent cell to the CRS of the cell is included; when PCI module 3 is not conflicted, only the interference of the adjacent cell data area to the CRS of the cell is included.

Secondly, the terminal measures SINR based on a Channel State Information-Reference Signal (CSI-RS), quantizes the SINR to obtain CQI, and reports the CQI to the base station. The procedure of calculating SINR based on CSI-RS may refer to the following equation (2):

wherein,RSRP_CSI-RSrepresents the received power of the CSI-RS; i is_nRepresenting the interference of the adjacent cell n to the CSI-RS of the cell; n represents noise. In addition, I_nIncluding interference of the data area of the neighboring cell with the data area of the cell.

However, in some application scenarios, the link adaptation method in the prior art cannot accurately report the CQI, and thus cannot perform accurate link adaptation. For example: in a Beamforming (BF) application scenario, both CRS resources and CSI-RS resources cannot sense BF weighting gain, so that CQI obtained through measurement is relatively inaccurate, and accuracy of a link adaptation process is affected.

Disclosure of Invention

The invention provides a link self-adaptive method and device, which can report more accurate CQI so as to accurately perform link self-adaptive adjustment.

In order to achieve the purpose, the invention adopts the following technical scheme:

in a first aspect, the present invention provides a method for link adaptation, including:

receiving a terminal capability report message sent by user equipment;

sending a Channel Quality Indicator (CQI) reporting indication message to the user equipment according to the terminal capability of the user equipment and a transmission mode statistical result of the user equipment in a current statistical period, wherein the CQI reporting indication message is used for indicating the user equipment to report CQI in a mode corresponding to the terminal capability and the statistical result;

and carrying out modulation and coding strategy MCS order selection according to the CQI reported by the user equipment and the current transmission mode of the user equipment.

With reference to the first aspect, in a first implementation manner of the first aspect, the sending, to the user equipment, a channel quality indicator CQI report instruction message according to the terminal capability of the user equipment and a transmission mode statistical result of the user equipment in a current statistical period, where the CQI report instruction message is used to instruct the user equipment to report a CQI in a manner corresponding to the terminal capability and the statistical result, specifically includes:

and when the user equipment has the capability of measuring a user Dedicated Reference Signal (DRS) and the transmission mode of the user equipment at least comprises a Beam Forming (BF) mode in the current statistical period, sending a CQI reporting indication message to the user equipment, wherein the CQI reporting indication message is used for indicating the user equipment to report at least a CQI based on the DRS.

With reference to the first implementation manner of the first aspect, in a second implementation manner of the first aspect, the CQI reporting indication message includes a CQI reporting configuration field in a BF mode;

when the ue has the capability of measuring a DRS dedicated to a user and a transmission mode of the ue in a current statistical period at least includes a beamforming BF mode, sending a CQI report indication message to the ue, where the CQI report indication message is used to indicate the ue to report at least a CQI based on the DRS, specifically including:

when the user equipment has the capability of measuring the DRS and the proportion of a multiple-input multiple-output (MIMO) mode in a current statistical period is equal to the proportion of the BF mode, setting the value of a CQI reporting configuration field in the BF mode as a first value, wherein the CQI reporting indication message is used for indicating the user equipment to report the CQI based on the DRS and the CQI based on a cell-specific reference signal (CRS) or the CQI based on a channel state reference information signal (CSI-RS) at the same time periodically;

or

When the user equipment has the capability of measuring a DRS and the proportion of the MIMO mode in the current statistical period is greater than that of the BF mode, setting the value of a CQI reporting configuration field in the BF mode as a second value, wherein the CQI reporting indication message is used for indicating the user equipment to report the CQI based on the DRS in an aperiodic way and report the CQI based on the CRS or the CSI-RS in a periodic way;

or

And when the user equipment has the capability of measuring the DRS and the proportion of the MIMO mode in the current statistical period is smaller than the proportion of the BF mode, setting the value of a CQI reporting configuration field in the BF mode as a third value, wherein the CQI reporting indication message is used for indicating the user equipment to report the CQI based on the DRS periodically and report the CQI based on the CRS or the CSI-RS aperiodically.

With reference to the second implementation manner of the first aspect, in a third implementation manner of the first aspect, when the user equipment has a capability of measuring DRSs and a ratio of a MIMO mode in a current statistics period is equal to a ratio of the BF mode, the CQI reporting indication message is further configured to set a BF CQI field of a codeword 0/1 in a reporting message to a specific value when the user equipment is instructed that DRS resources are not scheduled in the current reporting period.

With reference to the second implementation manner of the first aspect, in a fourth implementation manner of the first aspect, when the user equipment has a capability of measuring a DRS and a ratio of the MIMO mode in a current statistical period is greater than a ratio of the BF mode, the CQI reporting indication message further includes a downlink control information format DCI0, where the DCI0 is used to indicate that the user equipment aperiodically reports a physical uplink shared channel, PUSCH, resource used by a CQI based on the DRS; and instructing the user equipment to measure only a signal to interference plus noise ratio (SINR) corresponding to a DRS of a downlink subframe where the DCI0 is located.

With reference to the second implementation manner of the first aspect, in a fifth implementation manner of the first aspect, the CQI reporting instruction message is further configured to instruct the ue to report only the CQI based on the DRS when a resource used for periodically reporting the CQI based on the CRS or the CSI-RS conflicts with a resource used for aperiodically reporting the CQI based on the DRS; and when the resources used for reporting the CQI based on the DRS periodically and reporting the CQI based on the CRS or the CSI-RS aperiodically conflict, only reporting the CQI based on the CRS or the CSI-RS.

With reference to the second implementation manner of the first aspect, in a sixth implementation manner of the first aspect, the performing modulation and coding strategy MCS selection according to the CQI reported by the ue and the current transmission mode of the ue specifically includes:

when receiving a DRS-based CQI and a CRS-or CSI-RS-based CQI which are simultaneously reported periodically by the user equipment in a current reporting period and the current transmission mode of the user equipment is a BF mode, performing MCS order selection according to the DRS-based CQI reported by the user equipment;

or

When receiving a CQI based on a DRS and a CQI based on a CRS or a CSI-RS which are simultaneously reported periodically by the user equipment in a current reporting period and the current transmission mode of the user equipment is an MIMO mode, performing MCS selection according to the CQI based on the CRS or the CSI-RS which is reported by the user equipment;

or

When only CRS or CSI-RS based CQI periodically reported by the user equipment is received in the current reporting period and the current transmission mode of the user equipment is an MIMO mode, performing MCS order selection according to the CRS or CSI-RS based CQI;

or

When CRS or CSI-RS based CQI periodically reported by the user equipment is received in a current reporting period and the current transmission mode of the user equipment is a BF mode, if DRS based CQI periodically reported by the user equipment is also received in the current reporting period, MCS order selection is carried out according to the DRS based CQI; otherwise, performing MCS order selection according to the CQI based on the CRS or the CSI-RS;

or

When only the CQI based on the DRS periodically reported by the user equipment is received in the current reporting period and the current transmission mode of the user equipment is a BF mode, performing MCS order selection according to the CQI based on the DRS;

or

And when the CQI based on the DRS periodically reported by the user equipment is received in the current reporting period and the current transmission mode of the user equipment is an MIMO mode, if the CQI based on the CRS or the CSI-RS periodically reported by the user equipment is also received in the current reporting period, performing MCS order selection according to the CQI based on the CRS or the CSI-RS, or else performing MCS order selection according to the CQI based on the DRS.

With reference to the sixth implementation manner of the first aspect, in a seventh implementation manner of the first aspect, after performing modulation and coding scheme MCS selection according to the CQI reported by the user equipment and a current transmission mode of the user equipment, the method further includes:

when receiving a CQI based on a DRS and a CQI based on a CRS or a CSI-RS reported by the user equipment in a current reporting period, determining a value of a first MCS according to the CQI based on the DRS; determining a value of a second MCS according to the CRS or CSI-RS based CQI; when the value of the first MCS is larger than the value of the second MCS, determining that the next transmission mode of the user equipment is a BF mode; otherwise, determining that the next transmission mode of the user equipment is the MIMO mode.

With reference to the first aspect or any one of the first, second, third, fourth, fifth, sixth, and seventh implementation manners of the first aspect, in an eighth implementation manner of the first aspect, the terminal capability reporting message includes a first field, where the first field is used to indicate whether the terminal supports measurement DRSs.

In a second aspect, the present invention further provides a link adaptation apparatus, including:

a receiving unit, configured to receive a terminal capability report message sent by a user equipment;

a sending unit, configured to send a Channel Quality Indicator (CQI) reporting indication message to the user equipment according to a terminal capability of the user equipment and a transmission mode statistical result of the user equipment in a current statistical period, where the CQI reporting indication message is used to indicate the user equipment to report a CQI in a manner corresponding to the terminal capability and the statistical result;

the receiving unit is further configured to receive a CQI reported by the user equipment;

and the processing unit is used for carrying out modulation and coding strategy MCS order selection according to the CQI reported by the user equipment and the current transmission mode of the user equipment.

With reference to the second aspect, in a first implementation manner of the second aspect, the sending unit is specifically configured to:

With reference to the first implementation manner of the second aspect, in a second implementation manner of the second aspect, the CQI reporting indication message sent by the sending unit includes a CQI reporting configuration field in a BF mode, and the sending unit is specifically configured to:

or

With reference to the second implementation manner of the second aspect, in a third implementation manner of the second aspect, the CQI reporting indication message sent by the sending unit is further configured to, when the user equipment has a capability of measuring DRSs and a ratio of a MIMO mode in a current statistics period is equal to a ratio of the BF mode, instruct the user equipment to set a BF CQI field of a codeword 0/1 in a reporting message to a specific value when the user equipment does not schedule DRS resources in the current reporting period.

With reference to the second implementation manner of the second aspect, in a fourth implementation manner of the second aspect, when the user equipment has a capability of measuring a DRS and a ratio of the MIMO mode in a current statistical period is greater than a ratio of the BF mode, the CQI report indication message sent by the sending unit further includes a downlink control information format DCI0, where the DCI0 is used to indicate that the user equipment aperiodically reports a physical uplink shared channel, PUSCH, resource used by a DRS-based CQI; and instructing the user equipment to measure only a signal to interference plus noise ratio (SINR) corresponding to a DRS of a downlink subframe where the DCI0 is located.

With reference to the second implementation manner of the second aspect, in a fifth implementation manner of the second aspect, the CQI reporting indication message sent by the sending unit is further configured to instruct the user equipment to report only the CQI based on the DRS when a resource used for periodically reporting the CQI based on the CRS or the CSI-RS conflicts with a resource used for aperiodically reporting the CQI based on the DRS; and when the resources used for reporting the CQI based on the DRS periodically and reporting the CQI based on the CRS or the CSI-RS aperiodically conflict, only reporting the CQI based on the CRS or the CSI-RS.

With reference to the second implementation manner of the second aspect, in a sixth implementation manner of the second aspect, the processing unit is specifically configured to:

or

When CRS or CSI-RS based CQI periodically reported by the user equipment is received in a current reporting period and the current transmission mode of the user equipment is a BF mode, if DRS based CQI aperiodically reported by the user equipment is also received in the current reporting period, MCS order selection is carried out according to the DRS based CQI; otherwise, performing MCS order selection according to the CQI based on the CRS or the CSI-RS;

or

When only the CQI based on the DRS periodically reported by the user equipment is received in the current reporting period and the current transmission mode of the user equipment is a BF mode, carrying out MCS order selection according to the CQI based on the DRS;

or

With reference to the sixth implementation manner of the second aspect, in a seventh implementation manner of the second aspect, the processing unit is further configured to determine, when receiving a DRS-based CQI and a CRS or CSI-RS-based CQI reported by the user equipment in a current reporting period, a value of a first MCS according to the DRS-based CQI; determining a value of a second MCS according to the CRS or CSI-RS based CQI; when the value of the first MCS is larger than the value of the second MCS, determining that the next transmission mode of the user equipment is a BF mode; otherwise, determining that the next transmission mode of the user equipment is the MIMO mode.

The link self-adaption method and the device provided by the invention indicate the user equipment to report the CQI in a mode corresponding to the capability and the transmission mode statistical result of the user equipment according to the terminal capability of the terminal equipment and the statistical result of the transmission mode of the user equipment, and then carry out MCS order selection according to the CQI reported by the user equipment to realize the adjustment of the transmission parameters in the link self-adaption process.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only some embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the drawings without creative efforts.

Fig. 1 is a schematic diagram of the overall implementation process of the link adaptation method;

fig. 2 is a flowchart illustrating a link adaptation method according to an embodiment of the present invention;

fig. 3 is a flowchart illustrating another link adaptation method according to an embodiment of the present invention;

fig. 4 is a schematic structural diagram of a link adaptation apparatus according to an embodiment of the present invention;

fig. 5 is a schematic structural diagram of another link adaptation apparatus according to an embodiment of the present invention.

Detailed Description

The technical solutions in the embodiments will be described clearly and completely with reference to the drawings in the embodiments, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

An embodiment of the present invention provides a link adaptive method, which may be applied to a Long Term Evolution network (LTE) or other communication systems with common pilots and user dedicated pilots, and is mainly applied to an interaction process between a base station and user equipment, where the following description describes a specific implementation process of the present invention with the base station as an execution subject, as shown in fig. 2, the method includes:

101: and receiving a terminal capability report message sent by the user equipment.

The base station and the user equipment need to negotiate the terminal capability of the user equipment first. Different types of user equipment have different terminal capabilities, for example: the adopted terminal protocol version is R8, and the terminal of R11 can support measurement CRS only, and can also support measurement CSI-RS.

In the specific implementation process of this step, a dl-DRS-CQI-measure field needs to be added in a terminal capability reporting message (UECapability Information), where the dl-DRS-CQI-measure field is used to indicate whether the UE supports measuring a user-specific reference signal (DRS) for reporting CQI. For example: when the value of the dl-DRS-cqi-measure field is 1, indicating that the user equipment supports measurement DRS; when the value of the dl-DRS-cqi-measure field is 0, it indicates that the user equipment does not support the measurement DRS.

102: and sending a Channel Quality Indicator (CQI) reporting indication message to the user equipment according to the terminal capability of the user equipment and the transmission mode statistical result of the user equipment in the current statistical period, wherein the CQI reporting indication message is used for indicating the user equipment to report CQI in a mode corresponding to the terminal capability and the statistical result.

Currently, ten transmission modes of TM 1-TM 10 are commonly defined in LTE, wherein TM 1-TM 6 mainly adopt Multiple-Input Multiple-Output (MIMO) technology, and belong to MIMO transmission modes; TM 7-TM 10 adopt Beamforming (BF) technology, and belong to BF transmission mode. Thus, at a certain moment, the transmission mode of the user equipment may be BF mode, and may also be MIMO mode.

The transmission mode statistics result of the ue in the current statistics period in this step refers to statistics of the transmission mode of the ue at intervals. For example: and counting the transmission mode of the user equipment in the period of time every half hour, wherein the obtained statistical result is that the user equipment is in the transmission mode of the BF mode for 80% of the time and in the MIMO mode for 20% of the time in the current statistical period.

And the base station configures a CQI reporting mode and specific contents to be reported by the user equipment according to the terminal capability of the user equipment and the transmission mode statistical result of the user equipment in the current statistical period.

In a specific implementation process of this step, when the ue has a capability of measuring a DRS dedicated to a user and a transmission mode of the ue in a current statistical period at least includes a beam forming BF mode, sending a CQI report instruction message to the ue, where the CQI report instruction message is used to instruct the ue to report at least a CQI based on the DRS.

The method comprises the following steps that a user-specific reference signal (DRS) can sense the interference of the occupation situation of a Physical Resource Block (PRB) of a neighbor cell to a data area of the cell, and meanwhile, the DRS can sense BF weighting gain through precoding matrix weighting; the "reporting at least the CQI based on the DRS" referred to in the implementation process includes reporting only the CQI based on the DRS, and also includes reporting both the CQI based on the DRS and the CQI based on the CRS or CSI-RS.

And when the user equipment only has the capability of measuring the CRS or the CSI-RS, sending CQI reporting indication messages for indicating the user equipment to report the CQI based on the CRS or the CSI-RS to the user equipment.

103: and carrying out modulation and coding strategy MCS order selection according to the CQI reported by the user equipment and the current transmission mode of the user equipment.

After receiving the CQI reported by the ue, the base station needs to select a CQI corresponding to a current transmission mode of the ue to reasonably and accurately determine a Modulation and Coding Scheme (MCS) value. For example: and when the CQI based on the DRS and the CQI based on the CRS or the CSI-RS reported by the user equipment are received at the same time and the current transmission mode of the user equipment is a BF mode, carrying out MCS order selection according to the CQI based on the DRS and determining the value of the MCS.

The link self-adaption method provided by the invention instructs the user equipment to report the CQI in a mode corresponding to the capability and the transmission mode statistical result of the user equipment according to the terminal capability of the terminal equipment and the statistical result of the transmission mode of the user equipment, and then carries out MCS order selection according to the CQI reported by the user equipment to realize the adjustment of the transmission parameters in the link self-adaption process.

For clearly explaining the method shown in fig. 1, in a specific implementation process of step 102, the CQI reporting indication message includes a CQI reporting configuration (CQI _ report _ mode _ BF _ config) field in a BF mode, and corresponds to different CQI reporting manners. The base station can determine whether CRS/CSI-RS CQI and DRS CQI need to be reported simultaneously or are dominant or DRS CQI is dominant so as to flexibly configure the value of the field according to the proportion of the MIMO mode and the BF mode.

Therefore, the step 102 "when the ue has the capability of measuring the DRS dedicated to the user and the transmission mode of the ue in the current statistical period at least includes the beamforming BF mode, sending the CQI report indication message to the ue" specifically includes the following three cases:

in the first case: when the user equipment has the capability of measuring the DRS and the proportion of a multiple-input multiple-output MIMO mode in the current statistical period is equal to the proportion of the BF mode, setting the value of a CQI reporting configuration field in the BF mode as a first value, wherein the CQI reporting indication message is used for indicating the user equipment to report the CQI based on the DRS and the CQI based on the CRS of the cell dedicated reference signal or the CQI based on the CSI-RS at the same time periodically.

In the second case: when the user equipment has the capability of measuring the DRS and the proportion of the MIMO mode in the current statistical period is greater than the proportion of the BF mode, that is, the main transmission mode of the user equipment is the MIMO mode, setting the value of a CQI reporting configuration field in the BF mode as a second value, wherein the CQI reporting indication message is used for indicating the user equipment to report the CQI based on the DRS aperiodically and report the CQI based on the CRS or the CSI-RS periodically;

in the third case: when the ue has the capability of measuring DRS and the ratio of the MIMO mode in the current statistical period is smaller than the ratio of the BF mode, that is, the main transmission mode of the ue is indicated as BF mode, a value of a CQI reporting configuration field in the BF mode is set as a third value, and the CQI reporting indication message is used to indicate the ue to report the DRS-based CQI periodically and report the CRS-or CSI-RS-based CQI aperiodically.

In any case, the specific implementation manner of the CQI indicating the user equipment based on the DRS is as follows: (1) if the BF subframe of normal scheduling exists, measuring the BF subframe of normal scheduling to obtain CQI based on DRS; (2) and if the BF subframe which is normally scheduled does not exist, acquiring the CQI based on the DRS by adopting a mode of tentatively scheduling the BF subframe.

In addition, when the user equipment only has the capability of measuring the CRS or the CSI-RS, the value of the CQI reporting configuration field in the BF mode is a fourth value, and the CQI reporting indication message is used for indicating the user equipment to report only the CQI based on the CRS or the CSI-RS.

Therefore, in the prior art, for an application scenario in which the ue mainly operates in the BF mode and the ue supports measurement of the DRS, the ue is instructed to report the CQI based on the CRS or CSI-RS. In the invention, the user equipment is instructed to report the CQI based on the DRS, and the method has the following beneficial effects:

for example: suppose that the CQI reported by the user based on the CRS is 12, the number of transmit antennas of the base station is 8T, the number of receive antennas of the user is 2R, and the BF weighting gain is 2. And if the user reports the CQI based on the DRS at the moment, reporting the CQI to 14. If the coding modulation mode is selected according to the CQI reported based on the CRS, the base station works in 12 orders; if the coding modulation mode is selected according to the CQI reported based on the DRS, the base station works in 14 orders. When the spectrum efficiency corresponding to CQI 12 is 3.9023 and the spectrum efficiency corresponding to CQI 14 is 5.1152, the spectrum efficiency can be improved (5.1152-3.9023)/3.9023 is 31.08% if the coding modulation method is selected by using the CQI reported by the DRS. In consideration of the loss caused by retransmission, assuming the most extreme case, the retransmission rate of the terminal is 0 at 12 th order and 10% at 14 th order, the most conservative throughput gain is {5.1152 × 1-10%) -3.9023}/3.9023 ═ 17.97%.

As a specific application to the above situation, the meaning of the field value of the new field, CQI reporting configuration field in BF mode, is as shown in table one below:

watch 1

Wherein, the first value, the second value and the third value respectively correspond to three values of '01', '10' and '11'; the fourth value above corresponds to the value "00" in table one.

The base station side can flexibly select a CQI reporting mode according to the transmission mode of the user equipment. If the transmission mode of the ue is mainly the BF mode, only CQI _ report _ mode _ BF _ config needs to be configured, that is, the ue only needs to periodically report the CQI based on the DRS and report the CQI based on the CRS/CSI-RS under the event trigger condition, so that the BF gain can be accurately measured and the overhead can be reduced as much as possible. If the transmission mode of the ue is mainly the MIMO mode, only the configuration CQI _ report _ mode _ BF _ config is required to be "10", and the ue only needs to report the CQI based on the CRS/CSI-RS periodically, and only under the event trigger condition, the CQI based on the DRS is reported, so that the overhead can be reduced as much as possible.

The reporting content of the CQI based on the DRS at the user equipment side is specifically shown in tables two to four below:

watch two

Field(s)	Bit width (unit: bit)
		Wideband CQI	4
BF CQI	4

Watch III

Watch four

The reported content of the CQI based on the CRS or CSI-RS is specifically shown in tables five to seven below:

watch five

Field(s)	Bit width (unit: bit)
		Wideband CQI	4

Watch six

Watch seven

It should be added that, for the case that the ue has the capability of measuring DRS and the ratio of the MIMO mode in the current statistical period is equal to the BF mode, in addition to instructing the ue to report the DRS-based CQI and the CRS-or CSI-RS-based CQI periodically, the CQI report indication message is also used to instruct the ue to set the BF CQI field of the codeword 0/1 in the report message to a specific value when the DRS resource is not scheduled in the current reporting period. Wherein the specific value may be 1111 as specified by the protocol.

It should be further added that, for a case that the ue has the capability of measuring DRS and the ratio of the MIMO mode is greater than the ratio of the BF mode in the current statistical period, the CQI reporting indication message is used to instruct the ue to report the CQI based on CRS or CSI-RS in a periodic reporting manner, and to report the CQI based on DRS in an aperiodic reporting manner, and the CQI reporting indication message further includes downlink control information format 0(downlink control information format0, DCI0), and the DCI0 is used to instruct the ue to report the Physical Uplink Shared Channel (PUSCH) resource used by the CQI based on DRS aperiodically; and instructing the user equipment to measure only a signal to interference plus noise ratio (SINR) corresponding to a DRS of a downlink subframe where the DCI0 is located; in addition, the CQI report instruction message is further configured to instruct the ue to report only the DRS-based CQI when the resource used for periodically reporting the CRS or CSI-RS-based CQI conflicts with the resource used for aperiodic reporting of the DRS-based CQI. Similarly, when the resources used for reporting the CQI based on the DRS periodically and reporting the CQI based on the CRS or the CSI-RS aperiodically conflict, only reporting the CQI based on the CRS or the CSI-RS.

As a specific implementation of the method shown in fig. 2, in a specific implementation process of "performing modulation and coding strategy MCS selection according to the CQI reported by the ue and the current transmission mode of the ue" in step 103, the following six cases are specifically included:

in the first case: and when the CQI based on the DRS and the CQI based on the CRS or the CSI-RS which are simultaneously reported periodically by the user equipment are received in the current reporting period and the current transmission mode of the user equipment is a BF mode, carrying out MCS order selection according to the CQI based on the DRS reported by the user equipment.

In the second case: and when the CQI based on the DRS and the CQI based on the CRS or the CSI-RS which are simultaneously reported periodically by the user equipment are received in the current reporting period and the current transmission mode of the user equipment is an MIMO mode, carrying out MCS order selection according to the CQI based on the CRS or the CSI-RS which is reported by the user equipment.

In the third case: and when only CRS or CSI-RS based CQI periodically reported by the user equipment is received in the current reporting period and the current transmission mode of the user equipment is an MIMO mode, performing MCS order selection according to the CRS or CSI-RS based CQI.

In a fourth case: when CRS or CSI-RS based CQI periodically reported by the user equipment is received in a current reporting period and the current transmission mode of the user equipment is a BF mode, if DRS based CQI periodically reported by the user equipment is also received in the current reporting period, MCS order selection is carried out according to the DRS based CQI; otherwise, performing MCS order selection according to the CQI based on the CRS or the CSI-RS.

In the fifth case: and when only the CQI based on the DRS periodically reported by the user equipment is received in the current reporting period and the current transmission mode of the user equipment is a BF mode, performing MCS order selection according to the CQI based on the DRS.

In the sixth case: and when the CQI based on the DRS periodically reported by the user equipment is received in the current reporting period and the current transmission mode of the user equipment is an MIMO mode, if the CQI based on the CRS or the CSI-RS periodically reported by the user equipment is also received in the current reporting period, performing MCS order selection according to the CQI based on the CRS or the CSI-RS, or else performing MCS order selection according to the CQI based on the DRS.

It is to be added that, if the ue is just switched from the MIMO mode to the BF mode, and the current ue is in the BF mode, the DRS-based CQI sent by the ue may not be received in the current period, and the DRS-based CQI may be obtained by adopting a heuristic scheduling BF subframe to perform MCS selection, or the DRS-based CQI may be used in the first period to perform MCS selection, and then the DRS-based CQI periodically transmitted by the ue is received and then used to perform MCS selection.

As a supplement to the methods shown in the above figures, after the step 103 "performing modulation and coding strategy MCS selection according to the CQI reported by the ue and the current transmission mode of the ue", as shown in fig. 3, the method further includes:

201: when receiving a CQI based on a DRS and a CQI based on a CRS or a CSI-RS reported by the user equipment in a current reporting period, determining a value of a first MCS according to the CQI based on the DRS; determining a value of a second MCS according to the CRS or CSI-RS based CQI; when the value of the first MCS is larger than the value of the second MCS, determining that the next transmission mode of the user equipment is a BF mode; otherwise, determining that the next transmission mode of the user equipment is the MIMO mode.

After MCS selection, if both DRS-based CQI and CRS-or CSI-RS-based CQI are received in the current period, it is necessary to determine the corresponding MCS values according to the two CQIs, and then determine the next transmission mode of the user equipment according to the MCS values.

As a specific implementation of the method shown in each of the above diagrams, an embodiment of the present invention further provides a link adaptation apparatus, as shown in fig. 4, specifically including:

a receiving unit 301, configured to receive a terminal capability report message sent by a user equipment.

A sending unit 302, configured to send a CQI report instruction message to the user equipment according to the terminal capability of the user equipment and a transmission mode statistical result of the user equipment in a current statistical period, where the CQI report instruction message is used to instruct the user equipment to report CQI in a manner corresponding to the terminal capability and the statistical result.

A receiving unit 301, further configured to receive a CQI reported by the user equipment;

a processing unit 303, configured to perform modulation and coding strategy MCS selection according to the CQI reported by the ue and the current transmission mode of the ue.

Further, the sending unit 302 is specifically configured to:

Further, the CQI report indication message sent by the sending unit 302 includes a CQI report configuration field in a BF mode, and the sending unit 302 is specifically configured to:

or

Further, the CQI reporting indication message sent by the sending unit 302 is further configured to set a BF CQI field of a codeword 0/1 in a reporting message to a specific value when the user equipment has a capability of measuring DRSs and the ratio of the MIMO mode in the current statistical period is equal to the ratio of the BF mode and the user equipment is instructed not to schedule DRS resources in the current reporting period.

Further, when the ue has the capability of measuring DRS and the ratio of the MIMO mode in the current statistical period is greater than the ratio of the BF mode, the CQI report indication message sent by the sending unit 302 further includes DCI0 in downlink control information format, where the DCI0 is used to indicate that the ue aperiodically reports the PUSCH resource of the physical uplink shared channel used by the CQI based on the DRS; and instructing the user equipment to measure only a signal to interference plus noise ratio (SINR) corresponding to a DRS of a downlink subframe where the DCI0 is located.

Further, the CQI report indication message sent by the sending unit 302 is further configured to instruct the ue to report only the CQI based on the DRS when the resource used for periodically reporting the CQI based on the CRS or the CSI-RS conflicts with the resource used for aperiodically reporting the CQI based on the DRS; and when the resources used for reporting the CQI based on the DRS periodically and reporting the CQI based on the CRS or the CSI-RS aperiodically conflict, only reporting the CQI based on the CRS or the CSI-RS.

Further, the processing unit 303 is specifically configured to:

or

Further, the processing unit 303 is further configured to:

As a specific implementation of the method shown in the above figures, an embodiment of the present invention further provides a link adaptation apparatus, as shown in fig. 5, which specifically includes a receiver 401, a processor 402, a transmitter 403, a memory 404, and a bus 405, where the receiver 401, the processor 402, the transmitter 403, and the memory 404 are connected to each other through the bus 405, where:

the receiver 401 is configured to receive a terminal capability report message sent by a user equipment.

The processor 402 is configured to determine a CQI reporting mode according to the terminal capability of the ue and a transmission mode statistical result of the ue in a current statistical period.

A transmitter 403, configured to send a CQI report indication message to the ue, where the CQI report indication message is used to indicate that the ue reports CQI in a CQI report manner determined by the processor 402.

The receiver 401 is further configured to receive the CQI reported by the ue.

The processor 402 is further configured to perform modulation and coding strategy MCS selection according to the CQI reported by the ue and the current transmission mode of the ue.

Further, the processor 402 is specifically configured to:

when the user equipment has the capability of measuring a user Dedicated Reference Signal (DRS) and the transmission mode of the user equipment at least comprises a Beam Forming (BF) mode in the current statistical period, determining that the CQI reporting mode of the user equipment is at least reporting the CQI based on the DRS; correspondingly, the transmitter 403 sends a CQI report indication message to the ue, where the CQI report indication message is used to instruct the ue to report at least a DRS-based CQI.

Further, the CQI reporting indication message sent by the transmitter 403 includes a CQI reporting configuration field in BF mode, where:

or

Further, the CQI reporting indication message sent by the transmitter 403 is further configured to set a BF CQI field of a codeword 0/1 in a reporting message to a specific value when the user equipment has a capability of measuring DRSs and the ratio of the MIMO mode in the current statistics period is equal to the ratio of the BF mode and the user equipment is instructed not to schedule DRS resources in the current reporting period.

Further, when the ue has the capability of measuring DRSs and the ratio of the MIMO mode in the current statistical period is greater than the ratio of the BF mode, the CQI reporting indication message sent by the transmitter 403 further includes a downlink control information format DCI0, where the DCI0 is used to indicate that the ue aperiodically reports physical uplink shared channel, PUSCH, resources used by the DRS-based CQI; and instructing the user equipment to measure only a signal to interference plus noise ratio (SINR) corresponding to a DRS of a downlink subframe where the DCI0 is located.

Further, the CQI reporting indication message sent by the transmitter 403 is further configured to instruct the ue to report only the DRS-based CQI when the resource used for reporting the CRS or CSI-RS-based CQI periodically conflicts with the resource used for reporting the DRS-based CQI aperiodically; and when the resources used for reporting the CQI based on the DRS periodically and reporting the CQI based on the CRS or the CSI-RS aperiodically conflict, only reporting the CQI based on the CRS or the CSI-RS.

Further, the processor 402 is specifically configured to:

or

Further, the processor 402 is further configured to determine a value of a first MCS according to the DRS-based CQI when the DRS-based CQI and the CRS or CSI-RS-based CQI reported by the user equipment are received in a current reporting period; determining a value of a second MCS according to the CRS or CSI-RS based CQI; when the value of the first MCS is larger than the value of the second MCS, determining that the next transmission mode of the user equipment is a BF mode; otherwise, determining that the next transmission mode of the user equipment is the MIMO mode.

It should be noted that the processor 402 according to the embodiment of the present invention may be a single processor, or may be a general term for multiple processing elements. For example, the processor may be a Central Processing Unit (CPU), an Application Specific Integrated Circuit (ASIC), or one or more Integrated circuits configured to implement embodiments of the present invention, such as: one or more microprocessors (digital signal processors, DSP for short), or one or more field programmable Gate arrays (FPGA for short).

The memory 404 may be a single storage device or a combination of storage elements, and is used for storing executable program codes and the like. And the memory may include a Random Access Memory (RAM) or a non-volatile memory (non-volatile memory), such as a magnetic disk memory, Flash memory (Flash), etc.

The bus 405 may be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, an Extended ISA (EISA) bus, or the like. The bus may be divided into an address bus, a data bus, a control bus, etc. For ease of illustration, only one thick line is shown in FIG. 5, but this is not intended to represent only one bus or type of bus.

Through the above description of the embodiments, those skilled in the art will clearly understand that the present invention may be implemented by software plus necessary general hardware, and certainly may also be implemented by hardware, but in many cases, the former is a better embodiment. Based on such understanding, the technical solutions of the present invention may be substantially implemented or a part of the technical solutions contributing to the prior art may be embodied in the form of a software product, which is stored in a readable storage medium, such as a floppy disk, a hard disk, or an optical disk of a computer, and includes several instructions for enabling a computer device (which may be a personal computer, a server, or a network device) to execute the methods according to the embodiments of the present invention.

The above description is only for the specific embodiments of the present invention, but the scope of the present invention 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 invention, and all the changes or substitutions should be covered within the scope of the present invention.

Claims

1. A method of link adaptation, comprising:

receiving a terminal capability report message sent by user equipment;

2. The link adaptation method according to claim 1, wherein the sending the CQI report direction message to the ue according to the ue capability and the transmission mode statistic result of the ue in the current statistic period specifically includes:

3. The link adaptation method according to claim 2, wherein the CQI report indication message includes a CQI report configuration field in BF mode;

or

4. The link adaptation method of claim 3, wherein the CQI reporting indication message is further configured to set a BF CQI field of a codeword 0/1 in a reporting message to a specific value when the UE has a capability of measuring DRS and a ratio of MIMO mode in a current statistical period is equal to a ratio of the BF mode, and the UE is not scheduled with DRS resources in the current reporting period.

5. The method of claim 3, wherein when the UE has the capability of measuring DRS and the ratio of the MIMO mode is greater than the ratio of the BF mode in a current statistical period, the CQI reporting indication message further includes a downlink control information format DCI0, where the DCI0 is used to indicate a Physical Uplink Shared Channel (PUSCH) resource used by the UE to report the DRS-based CQI aperiodically; and instructing the user equipment to measure only a signal to interference plus noise ratio (SINR) corresponding to a DRS of a downlink subframe where the DCI0 is located.

6. The link adaptation method of claim 3, wherein the CQI reporting indication message is further configured to instruct the UE to report only the CQI based on the DRS when the CQI based on the CRS or the CSI-RS is reported periodically and a resource used for reporting the CQI based on the DRS aperiodically collides; and when the resources used for reporting the CQI based on the DRS periodically and reporting the CQI based on the CRS or the CSI-RS aperiodically conflict, only reporting the CQI based on the CRS or the CSI-RS.

7. The link adaptation method according to claim 3, wherein the performing modulation and coding strategy MCS selection according to the CQI reported by the UE and the current transmission mode of the UE specifically comprises:

or

8. The method of claim 7, wherein after performing Modulation and Coding Scheme (MCS) selection according to the CQI reported by the UE and the current transmission mode of the UE, the method further comprises:

9. The method according to any one of claims 1 to 8, wherein the terminal capability report message includes a first field, and the first field is used to indicate whether the terminal supports measurement DRS.

10. An apparatus for link adaptation, comprising:

11. The link adaptation apparatus according to claim 10, wherein the sending unit is specifically configured to:

12. The link adaptation apparatus of claim 11,

the CQI report indication message sent by the sending unit includes a CQI report configuration field in a BF mode, and the sending unit is specifically configured to:

or

When the user equipment has the capability of measuring a DRS and the proportion of the MIMO mode in the current statistical period is larger than that of the BF mode, setting the value of a CQI reporting configuration field in the BF mode as a second value, wherein the CQI reporting indication message is used for indicating the user equipment to report the CQI based on the DRS in an aperiodic way and report the CQI based on the CRS or the CSI-RS in a periodic way;

or

13. The apparatus of claim 12, wherein the CQI reporting indication message sent by the sending unit is further configured to set a BF CQI field of a codeword 0/1 in a reporting message to a specific value when the user equipment has a capability of measuring DRSs and a ratio of MIMO modes in a current statistics period is equal to a ratio of the BF modes, and the user equipment is instructed not to schedule DRS resources in the current reporting period.

14. The apparatus of claim 12, wherein when the ue has the capability of measuring DRSs and the ratio of the MIMO mode in a current statistical period is greater than the ratio of the BF mode, the CQI report indication message sent by the sending unit further includes a downlink control information format DCI0, where the DCI0 is used to indicate a Physical Uplink Shared Channel (PUSCH) resource used by the ue to report DRS-based CQI aperiodically; and instructing the user equipment to measure only a signal to interference plus noise ratio (SINR) corresponding to a DRS of a downlink subframe where the DCI0 is located.

15. The apparatus of claim 12, wherein the CQI reporting indication message sent by the sending unit is further configured to instruct the ue to report only a DRS-based CQI when a resource used for reporting a CRS-or CSI-RS-based CQI periodically conflicts with a resource used for reporting a DRS-based CQI aperiodically; and when the resources used for reporting the CQI based on the DRS periodically and reporting the CQI based on the CRS or the CSI-RS aperiodically conflict, only reporting the CQI based on the CRS or the CSI-RS.

16. The link adaptation device according to claim 12, wherein the processing unit is specifically configured to:

or

17. The apparatus of claim 16,

the processing unit is further configured to determine a value of a first MCS according to the DRS-based CQI when the DRS-based CQI and the CRS-or CSI-RS-based CQI reported by the user equipment are received in a current reporting period; determining a value of a second MCS according to the CRS or CSI-RS based CQI; when the value of the first MCS is larger than the value of the second MCS, determining that the next transmission mode of the user equipment is a BF mode; otherwise, determining that the next transmission mode of the user equipment is the MIMO mode.