CN103580784A - Modulation mode and code rate selecting method based on channel quality indication and base station - Google Patents

Abstract

The invention relates to a method and base station for selecting modulation mode and code rate based on channel quality indication. The method comprises: a CQI receiving step, the base station receives the channel quality indication (CQI) measurement value reported by the terminal; a capability judging step, the base station judges whether CQI information under different conditions is needed and whether the terminal has the ability to report CQI information under different conditions Ability; CQI correction step, when it is judged that CQI information under different conditions is required and the terminal does not have the reporting capability, the base station corrects the CQI measurement value reported by the terminal to obtain the final CQI correction value under different conditions; modulation In the selection step, when scheduling the terminal, the base station selects a modulation scheme and a code rate according to the final CQI correction value under the current corresponding conditions of the terminal. The method and base station of the invention can improve system throughput and frequency spectrum efficiency.

Description

Method and base station for selecting modulation scheme and code rate based on channel quality indication

technical field

The invention relates to the field of wireless communication, in particular to a method for selecting a modulation mode and a code rate based on channel quality indication and a base station.

Background technique

In a wireless communication system, in order to better select an appropriate modulation method, code rate and MIMO method according to downlink channel quality, the base station needs to measure and report the channel quality. For the downlink, the terminal equipment UE measures the quality of the downlink channel and reports the channel quality indication information of the downlink to the base station; for the uplink, the base station measures the quality of the uplink channel and reports the channel quality indication information of the uplink to the base station Related scheduling modules. In a wireless communication system, due to measurement errors or channel changes between measurement time and transmission time, the reported channel quality information may be inaccurate. The channel quality indication information is corrected and calculated, and then the corrected channel quality information is used to select an appropriate modulation method, code rate, and the like. For example, in the LTE system, for the downlink, the UE reports the CQI information of the downlink channel quality indicator; the base station directly selects the appropriate modulation method, code rate and MIMO method based on the CQI information reported by the UE, or based on the CQI information reported by the UE , and modify the CQI according to the link transmission performance such as the number of ACK/NACK or the block error rate BLER, etc., and use the modified CQI to select an appropriate modulation method, code rate, etc.

For channel quality under different conditions and scenarios, there are two existing processing methods: one is to measure and report channel quality information separately for different conditions and scenarios. This method needs to increase signaling overhead and protocols to indicate different conditions and scenarios Support, and increase the overhead of channel quality reporting; the second is to uniformly measure and report different conditions and scenarios. The existing channel quality indicator information correction method uses the same correction method for channel quality indicator information under all conditions and scenarios. Distinguish different channel qualities under different conditions and scenarios; at this time, the modulation mode and code rate selected based on the existing channel quality indication information correction method are not suitable for different conditions and scenarios, which affects system throughput.

Contents of the invention

The technical problem to be solved by the present invention is to provide a method and a base station for selecting a modulation mode and a code rate based on a channel quality indication, so as to solve the problem that the system throughput is affected.

In order to solve the above-mentioned technical problems, the present invention provides a method for selecting a modulation mode and a code rate based on a channel quality indicator, the method comprising:

CQI receiving step, the base station receives the channel quality indicator (CQI) measurement value reported by the terminal;

In a capability judging step, the base station judges whether CQI information under different conditions is needed and whether the terminal has the ability to report CQI information under different conditions;

CQI correction step, when it is judged that CQI information under different conditions is required and the terminal does not have the reporting capability, the base station corrects the CQI measurement value reported by the terminal to obtain a final CQI correction value under different conditions;

In the modulation selection step, when scheduling the terminal, the base station selects a modulation mode and a code rate according to the final CQI correction value under the current corresponding conditions of the terminal.

In order to solve the above technical problems, the present invention also provides a base station, which includes:

The CQI receiving module is used to receive the channel quality indication (CQI) measurement value reported by the terminal;

A capability judging module, configured to judge whether CQI information under different conditions is required and whether the terminal has the ability to report CQI information under different conditions;

A CQI correction module, configured to correct and obtain the final CQI correction value under different conditions according to the CQI measurement value reported by the terminal when it is judged that CQI information under different conditions is required and the terminal does not have the reporting capability;

The modulation selection module is configured to select a modulation mode and a code rate according to the final CQI correction value under the current corresponding conditions of the terminal when scheduling the terminal.

When the method and the base station of the present invention determine that CQI information under different conditions is required and the terminal does not have the reporting capability of reporting CQI information under different conditions, the channel quality indicators are respectively corrected based on different conditions, so that the corrected channel quality indicators after correction can reflect different conditions Under the channel quality and appropriate modulation and code rate, thereby improving system throughput and system efficiency.

Description of drawings

FIG. 1 is a schematic diagram of an embodiment of a method for selecting a modulation scheme and a code rate based on a channel quality indication in the present invention;

Fig. 2 is a specific flow diagram of step 103 in Fig. 1;

FIG. 3 is a schematic diagram of a module structure of a base station embodiment of the present invention;

Fig. 4 is a schematic structural diagram of another module of the base station embodiment of the present invention.

Detailed ways

The following takes the heterogeneous network of the LTE-A system as an example to illustrate that the channel quality is different under different conditions and scenarios, but the existing channel quality indication information correction method does not take this situation into consideration.

The LTE-A R10 standard introduces support for heterogeneous networks, that is, high-power nodes are used for wide coverage, and low-power nodes are used for repeated coverage in hotspot areas or edge areas to enhance performance and improve system throughput. Due to the low downlink transmission power of low-power nodes, directly measured by the quality of downlink received signals, the coverage of low-power nodes is very small, which cannot effectively offload UE transmission requirements; therefore, in order to better offload data transmission requirements Generally, the coverage of low-power nodes is expanded by setting cell selection bias parameters and other methods. In this way, in the edge area where the low-power node expands coverage, the downlink signal power of the low-power node is lower than that of the high-power node, and the downlink signal of the high-power node will cause strong interference to UEs in the edge area of the low-power node. Therefore, in order to solve this interference problem, eICIC technology needs to be introduced. The eICIC technology is to set the high-power node ABS subframe (almost blank subframe, Almost Blank Subframe), so that the UE of the low-power node can perform data reception and more accurate measurement on the subframe corresponding to the high-power node ABS subframe etc., because there is almost no strong interference from high-power nodes at this time, and the downlink channel quality of UEs on low-power nodes is better. Obviously, on the ABS subframe of the high-power node and the normal subframe (non-ABS subframe), the interference characteristics of the UE of the low-power node are inconsistent, so that the measurement results are also different, that is, the ABS subframe of the high-power node It is a different scenario for a UE of a low-power node than a normal subframe (non-ABS subframe), and its channel quality is also different. In order to better support eICIC, the LTE R10 standard introduces measurement subset indication signaling to inform R10UE on which subsets to perform RRM/RLM measurement and CQI measurement of the serving cell and neighboring cells, so as to obtain the measurement amount more accurately. And the measurement results are consistent.

However, the introduction of the eICIC technology in the heterogeneous network brings new problems to the R8/9 UE measurement. Obviously, for the UE of the low-power node, there is almost no strong interference from the high-power node on the ABS subframe of the high-power node, the downlink channel quality is better, and the measured CQI is also higher; On the normal subframe (non-ABS subframe) of the power node, the UE of the low-power node is strongly interfered by the high-power node, the downlink channel quality is poor, and the measured CQI is low, that is to say, in the high-power node On ABS subframes and normal subframes (non-ABS subframes), the interference characteristics of low-power node UEs are inconsistent, so that the measurement results are also different, that is, ABS subframes of high-power nodes and normal subframes (non-ABS subframes) It is a different scenario for a UE of a low-power node, and its channel quality is also different. However, R8/9 UEs cannot receive measurement subset indication signaling like R10 UEs, and the subframes used for R8/9 UE measurement are determined by the UE itself; therefore, the base station cannot judge which subframes are used for R8/9 UE measurement, reflect If the downlink channel quality of which subframes is known, it is impossible to know the relationship between the CQI fed back by the R8/9 UE and the channel quality of ABS subframes and normal subframes (non-ABS subframes). If the CQI is directly used, or the CQI modified by the traditional CQI correction method is used to select the modulation method and code rate, it is difficult to accurately reflect the quality of the downlink, resulting in inappropriate selection of the modulation method and code rate, which affects the system throughput. On the subframe corresponding to the ABS subframe of the node, the UE channel quality of the low-power node is better, and the modulation method and code rate selected based on the feedback CQI are low, resulting in that the throughput cannot be effectively improved; while the ABS of the high-power node On the subframe corresponding to the subframe, the channel quality of the low-power node UE is poor, and the modulation method and code rate selected based on the feedback CQI are relatively high, resulting in a large BLER, a large number of retransmissions, and low throughput. In short, since the base station cannot know for sure which subframes the channel quality is reflected by the CQI fed back by the R8/9UE, using the CQI directly or modifying the CQI with the traditional method to select the modulation method and code rate will make the selected modulation method and code rate selection Inappropriate, affecting system throughput.

As shown in Figure 1, the present invention selects the method of modulation mode, code rate based on channel quality indication, and this method comprises:

Step 101: CQI receiving step, the base station receives the channel quality indicator (CQI) measurement value reported by the terminal;

Step 102: Capability judging step, the base station judges whether CQI information under different conditions is needed and whether the terminal has the ability to report CQI information under different conditions;

Understandably, if the base station judges that CQI information under different conditions is required and the terminal has the ability to report CQI information under different conditions, then in step 101, the base station may receive CQI measurement values or correction values under different conditions, and the base station may Select the corresponding encoding mode, code rate, etc. according to the existing technology.

Specifically, situations that require CQI information under different conditions include but are not limited to scenarios where eICIC technology is used, and terminals that do not have the capability include but are not limited to R8 version or R9 version (also referred to as R8/9 in this article) terminal.

The different conditions include:

A subframe set corresponding to a high-power node and/or femto almost blank subframe (ABS) and a subframe set corresponding to a high-power node and/or femto normal subframe; or, including:

A set of subframes corresponding to high power nodes and/or femto normal subframes; a set of subframes corresponding to high power nodes and/or femto zero power (Zero Power) subframes; and a high power node and/or femto reduced power (Reduted Power ) The subframe set corresponding to the subframe.

Step 103: CQI correction step, when it is judged that CQI information under different conditions is required and the terminal does not have the reporting capability, the base station corrects the CQI measurement value reported by the terminal to obtain a final CQI correction value under different conditions;

Specifically, the base station can use an existing method to modify the final CQI correction value under different conditions. Preferably, as shown in Figure 2, the CQI correction step to obtain the final CQI correction value under different conditions includes the following sub-steps:

Step 201: Statistical sub-step, counting the number of ACKs and the number of NACKs of UE downlink transmission blocks reporting CQI measurement values within a predetermined statistical period under various conditions;

Step 202: The measured value correction sub-step, before scheduling the terminal, cyclically corrects the CQI measured value reported by the terminal according to the number of ACKs and the number of NACKs to obtain the final CQI correction value under each condition;

In the sub-step of correcting the measured value, the CQI measured value is corrected according to the following formula:

分别为第i+1次和第i次修正后得到的CQI修正值，i＝0时，

为所述终端上报的CQI测量值，α和-β为修正因子，可以根据需要设置。优选地，满足α/β＝x/(1-x)，其中x为目标误块率。 ${\mathrm{CQI}}_{\mathrm{mod}\mathrm{ify}}^{i+1}={\mathrm{CQI}}_{\mathrm{mod}\mathrm{ify}}^i+\mathrm{\α}*N_{\mathrm{ACK}}-\mathrm{\β}*N_{\mathrm{NACK}},$ in,

are the CQI correction values obtained after the i+1th and i-th corrections respectively, when i=0,

For the CQI measurement value reported by the terminal, α and -β are correction factors, which can be set as required. Preferably, α/β=x/(1-x) is satisfied, where x is the target block error rate.

Step 104: a modulation selection step, when scheduling the terminal, the base station selects a modulation scheme and a code rate according to the final CQI correction value under the current corresponding conditions of the terminal.

In the method of the present invention, when the base station judges that CQI information under different conditions is needed and the terminal does not have the capability to report CQI information under different conditions, the channel quality indicators are respectively corrected based on different conditions, so that the corrected channel quality indicators can reflect different conditions Under the channel quality and appropriate modulation and code rate, thereby improving system throughput and system efficiency.

Embodiments of the present invention will be described in detail below in conjunction with the accompanying drawings. It should be noted that, in the case of no conflict, the embodiments in the present application and the features in the embodiments can be combined with each other.

Application example 1

The method for correcting channel quality indication information provided in this example is applicable to wireless communication systems, especially LTE-A (Long Term Evolution-Advanced, enhanced long-term evolution) systems. The following is a detailed introduction in combination with specific steps. In the system of this example, the subframes of the high-power nodes are divided into almost blank subframes (ABS) and normal subframes, and the UEs in this embodiment are R8/9UEs.

Step 301: UE calculates and obtains a downlink CQI measurement value according to the downlink channel estimation of several subframes, and feeds back the CQI measurement value to the base station, and the base station receives the channel quality indication (CQI) measurement value reported by the terminal;

Step 302: the base station judges whether CQI information under different conditions is required and whether the terminal has the reporting capability of reporting CQI information under different conditions;

In step 302, the base station determines that the UE is an R8/9 UE, and then executes step 303; otherwise, directly selects a modulation scheme and a code rate according to the CQI information reported by the UE.

Step 303: The base station corrects and obtains the final CQI correction value of the subframe set corresponding to the almost blank subframe (ABS) of the high-power node and the subframe set corresponding to the normal subframe of the high-power node according to the CQI measurement value reported by the terminal;

Specifically perform the following operations:

(a) to carry out statistics;

为一个ACK/NACK统计周期内高功率节点ABS子帧所对应的子帧集合上上报CQI测量值的UE下行传输块的ACK数目和NACK数目；设定变量

为一个ACK/NACK统计周期内高功率节点正常子帧(非ABS子帧)所对应的子帧集合上某个UE下行传输块的ACK数目和NACK数目。set variable

The number of ACKs and NACKs of the UE downlink transmission blocks that report the CQI measurement value for the subframe set corresponding to the ABS subframe of the high-power node within an ACK/NACK statistical period; set the variable

It is the number of ACKs and NACKs of a certain UE downlink transmission block on the subframe set corresponding to the normal subframe (non-ABS subframe) of the high-power node within one ACK/NACK statistical period.

清零；在每个ACK/NACK统计周期内，基站统计高功率节点ABS子帧所对应的子帧集合上某个UE下行传输块的ACK数目

和NACK数目

统计高功率节点正常子帧(非ABS子帧)所对应的子帧集合上某个UE下行传输块的ACK数目

和NACK数目

The base station repeatedly performs statistics on the number of ACKs and the number of NACKs in units of ACK/NACK statistics period. At the beginning of each ACK/NACK statistical period, the variable

Cleared; in each ACK/NACK statistical period, the base station counts the number of ACKs of a certain UE downlink transmission block on the subframe set corresponding to the ABS subframe of the high-power node

and the number of NACKs

Count the number of ACKs of a certain UE downlink transmission block on the subframe set corresponding to the normal subframe (non-ABS subframe) of the high-power node

and the number of NACKs

(b) Correction of measured values based on statistical results;

修正高功率节点ABS子帧所对应的子帧集合的信道质量指示，得到高功率节点ABS子帧所对应的子帧集合调度终端前的最终修正信道质量信息

根据修正高功率节点非ABS子帧所对应的子帧集合的信道质量指示，得到高功率节点非ABS子帧所对应的子帧集合调度终端前的最终修正信道质量信息

Before scheduling the terminal, the base station repeatedly corrects the channel quality indicator with the ACK/NACK statistical period as the unit. At the end of each ACK/NACK statistical period, the base station, according to

Correct the channel quality indication of the subframe set corresponding to the ABS subframe of the high-power node, and obtain the final corrected channel quality information before the terminal is scheduled by the subframe set corresponding to the ABS subframe of the high-power node

according to Correct the channel quality indication of the subframe set corresponding to the non-ABS subframe of the high-power node, and obtain the final corrected channel quality information before the terminal is scheduled for the subframe set corresponding to the non-ABS subframe of the high-power node

(或

)和

(或

)对信道质量指示信息的修正是结合各自的修正因子进行的，

(或

)的信道质量指示信息CQI修正因子为α，

(或)的信道质量指示信息CQI修正因子为-β，那么UE的修正后高功率节点ABS子帧对应的子帧集合的修正CQI更新如式子：In step (b),

(or

)and

(or

) The correction of the channel quality indication information is carried out in combination with the respective correction factors,

(or

) channel quality indication information CQI correction factor is α,

(or ) channel quality indication information CQI correction factor is -β, then the modified CQI update of the subframe set corresponding to the high-power node ABS subframe of the UE after correction is as follows:

${\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; ACK</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; NACK</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; ,</span>$

The modified CQI update method of the subframe set corresponding to the corrected high-power node normal subframe (non-ABS subframe) of the UE is similar, as follows:

${\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; ACK</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; NACK</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; ,</span>$

为所述终端上报的CQI测量值CQI^measured。Among them, i represents the i-th correction, when i=0,

The CQI measured value CQI ^measured reported by the terminal.

(或

)和(或

)对CQI修正因子设定与BLER相关。如BLER要求为x，

(或

)的CQI修正因子为α，(或

)的CQI修正因子为-β，α和β都是正数，且满足α/β＝x/(1-x)。α and -β are correction factors, which can be flexibly set according to the specific application environment or experience during specific implementation. Preferably, in step (b), in order to achieve the target block error rate BLER, the

(or

)and (or

) The setting of the CQI correction factor is related to the BLER. If BLER requires x,

(or

) CQI correction factor is α, (or

) CQI correction factor is -β, α and β are both positive numbers, and satisfy α/β=x/(1-x).

选择高功率节点ABS子帧所对应的子帧集合的调制方式、码率等；根据修正后的信道质量信息

选择高功率节点正常子帧(非ABS子帧)所对应的子帧集合的调制方式、码率等。Step 303: the base station according to the corrected channel quality information

Select the modulation mode, code rate, etc. of the subframe set corresponding to the ABS subframe of the high-power node; according to the corrected channel quality information

The modulation mode, code rate, etc. of the subframe set corresponding to the normal subframe (non-ABS subframe) of the high-power node are selected.

This example is applicable to the correction of UE downlink channel quality indication information after the eICIC technology is introduced in the heterogeneous network of the LTE-A system. Compared with the existing method, this example can obtain better corrected CQI information, and can more effectively indicate the downlink channel quality of the subframe corresponding to the ABS subframe of the high-power node and the normal subframe (non-ABS subframe), Therefore, different modulation schemes, code rates, etc. can be selected for subframes corresponding to high-power node ABS subframes and normal subframes (non-ABS subframes), to improve system throughput and efficiency.

Application example 2

The method for correcting channel quality indication information provided in this application example is applicable to wireless communication systems, especially LTE-A (Long Term Evolution-Advanced, enhanced long-term evolution) systems. The following is a detailed introduction in combination with specific examples. In this example system, the subframes of high-power nodes are divided into Zero Power (zero power) subframes, Reduced Power (reduced power) subframes and normal subframes, and the UE in this embodiment is R8/9UE.

On normal subframes (non-ABS subframes), Zero Power ABS subframes, and ReducedPower ABS subframes of high-power nodes, the downlink transmission power of high-power nodes is completely different. Therefore, in the scenario where these three subframes coexist , on the subframes of the low-power nodes corresponding to these three subframes, the UE of the low-power nodes receives different interference from the high-power nodes, and their downlink channel quality and measurement results are also different. Step 301: UE according to several subframes The downlink channel is estimated, and the downlink CQI measurement value is calculated, and the CQI measurement value is fed back to the base station, and the base station receives the channel quality indication (CQI) measurement value reported by the terminal;

Step 302: the base station judges whether CQI information under different conditions is required and whether the terminal has the reporting capability of reporting CQI information under different conditions;

In step 302, the base station determines that the UE is an R8/9 UE, and then executes step 303; otherwise, directly selects a modulation scheme and a code rate according to the CQI information reported by the UE.

Step 303: The base station corrects the subframe set corresponding to the Zero Power (zero power) subframe of the high-power node, the subframe set corresponding to the Reduced Power (reduced power) of the high-power node, and the high-power node according to the CQI measurement value reported by the terminal. The final CQI correction value of the subframe set corresponding to the normal subframe;

Specifically perform the following operations:

(a) to carry out statistics;

为一个ACK/NACK统计周期内高功率节点Zero Power ABS子帧所对应的子帧集合上某个R8/9UE下行传输块的ACK数目和NACK数目；设定变量

为一个ACK/NACK统计周期内高功率节点Reduced Power ABS子帧所对应的子帧集合上某个UE下行传输块的ACK数目和NACK数目。set variable It is the number of ACKs and NACKs of a certain R8/9 UE downlink transmission block on the subframe set corresponding to the normal subframe (non-ABS subframe) of the high-power node in an ACK/NACK statistical cycle; set the variable

It is the number of ACKs and NACKs of a certain R8/9UE downlink transmission block on the subframe set corresponding to the Zero Power ABS subframe of the high power node within an ACK/NACK statistical period; set the variable

It is the ACK number and NACK number of a certain UE downlink transmission block on the subframe set corresponding to the Reduced Power ABS subframe of the high power node within one ACK/NACK statistical period.

清零；在每个ACK/NACK统计周期内，基站统计高功率节点Zero Power ABS子帧所对应的子帧集合上某个UE下行传输块的ACK数目

和NACK数目统计高功率节点Reduced Power ABS子帧所对应的子帧集合上某个UE下行传输块的ACK数目和NACK数目

统计高功率节点正常子帧(非ABS子帧)所对应的子帧集合上某个UE下行传输块的ACK数目

和NACK数目

The base station repeatedly performs statistics on the number of ACKs and the number of NACKs in units of ACK/NACK statistics period. At the beginning of each ACK/NACK statistical period, the variable

Cleared: In each ACK/NACK statistical period, the base station counts the number of ACKs of a certain UE downlink transmission block on the subframe set corresponding to the Zero Power ABS subframe of the high power node

and the number of NACKs Count the number of ACKs of a certain UE downlink transmission block on the subframe set corresponding to the Reduced Power ABS subframe of the high power node and the number of NACKs

Count the number of ACKs of a certain UE downlink transmission block on the subframe set corresponding to the normal subframe (non-ABS subframe) of the high-power node

and the number of NACKs

(b) Correction of measured values based on statistical results;

循环修正高功率节点Zero Power ABS子帧所对应的子帧集合的信道质量指示，得到的高功率节点Zero Power ABS子帧所对应的子帧集合调度终端前的最终修正信道质量信息

根据

修正高功率节点Reduced Power ABS子帧所对应的子帧集合的信道质量指示，得到的高功率节点Reduced Power ABS子帧所对应的子帧集合调度终端前的最终修正信道质量信息根据

修正高功率节点非ABS子帧所对应的子帧集合的信道质量指示，得到的高功率节点非ABS子帧所对应的子帧集合调度终端前的最终修正信道质量信息

Before scheduling the terminal, the base station repeatedly corrects the channel quality indicator with the ACK/NACK statistical period as the unit. At the end of each ACK/NACK statistical period, the base station, according to

Cyclic correction of the channel quality indication of the subframe set corresponding to the Zero Power ABS subframe of the high-power node, and the obtained final corrected channel quality information before the terminal is scheduled for the subframe set corresponding to the Zero Power ABS subframe of the high-power node

according to

Correct the channel quality indication of the subframe set corresponding to the Reduced Power ABS subframe of the high-power node, and obtain the final corrected channel quality information before scheduling the terminal in the subframe set corresponding to the Reduced Power ABS subframe of the high-power node according to

Correct the channel quality indication of the subframe set corresponding to the non-ABS subframe of the high-power node, and obtain the final corrected channel quality information before the terminal is scheduled for the subframe set corresponding to the non-ABS subframe of the high-power node

(或)和(或

)对信道质量指示信息的修正是结合各自的修正因子进行的，

(或)的信道质量指示信息CQI修正因子为α，

(或

)的信道质量指示信息CQI修正因子为-β，那么UE的修正后高功率节点Zero Power ABS子帧对应的子帧集合的修正CQI更新如式子：In step (b),

(or )and (or

) The correction of the channel quality indication information is carried out in combination with the respective correction factors,

(or ) channel quality indication information CQI correction factor is α,

(or

) channel quality indication information CQI correction factor is -β, then the modified CQI update of the subframe set corresponding to the UE’s modified high-power node Zero Power ABS subframe is as follows:

${\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; Zero\; PABS</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; Zero\; PABS</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; ACK</span>}}^{\mathrm{<span\; class="notranslate">\; Zero\; PABS</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; NACK</span>}}^{\mathrm{<span\; class="notranslate">\; Zero\; PABS</span>}}<span\; class="notranslate">\; ,</span>$

The modified CQI update method of the UE's modified high-power node Reduced Power ABS and the subframe set corresponding to the normal subframe (non-ABS subframe) are similar, as follows:

${\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; Reduced\; PABS</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; Reduced\; PABS</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; ACK</span>}}^{\mathrm{<span\; class="notranslate">\; Reduced\; PABS</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; NACK</span>}}^{\mathrm{<span\; class="notranslate">\; Reduced\; PABS</span>}}$

${\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; ACK</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; NACK</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}$

为所述终端上报的CQI测量值CQI^measured。Among them, i represents the i-th correction, when i=0,

The CQI measured value CQI ^measured reported by the terminal.

)和

(或

)对CQI修正因子设定为不同。如BLER要求为x，

(或

)的CQI修正因子为α，

(或

)的CQI修正因子为-β，α和β都是正数，且满足α/β＝x/(1-x)。α and -β are correction factors, which can be flexibly set according to the specific application environment or experience during specific implementation. Preferably, in step (b), in order to achieve the target block error rate BLER, the (or

)and

(or

) is set to be different for the CQI correction factor. If BLER requires x,

(or

) CQI correction factor is α,

(or

) CQI correction factor is -β, α and β are both positive numbers, and satisfy α/β=x/(1-x).

选择高功率节点Zero Power ABS子帧所对应的子帧集合的调制方式、码率等；根据修正后的信道质量信息

选择高功率节点Reduced Power ABS子帧所对应的子帧集合的调制方式、码率等；根据修正后的信道质量信息选择高功率节点正常子帧(非ABS子帧)所对应的子帧集合的调制方式、码率等。Step 303: the base station according to the corrected channel quality information

Select the modulation method, code rate, etc. of the subframe set corresponding to the Zero Power ABS subframe of the high-power node; according to the corrected channel quality information

Select the modulation mode, code rate, etc. of the subframe set corresponding to the Reduced Power ABS subframe of the high-power node; according to the corrected channel quality information The modulation mode, code rate, etc. of the subframe set corresponding to the normal subframe (non-ABS subframe) of the high-power node are selected.

This example is applicable to the heterogeneous network of the LTE-A system. After the introduction of eICIC technology, the high-power node Zero ABS subframe, Reduce Power ABS subframe and normal subframe (non-ABS subframe) coexist. Modification of channel quality indication information. Compared with the existing methods, this example can obtain better corrected CQI information, and can more effectively indicate the high-power node Zero ABS subframe, Reduce Power ABS subframe and normal subframe (non-ABS subframe) corresponding The downlink channel quality of the subframe, therefore, can select different modulation modes, code rates, etc. Improve system throughput and efficiency.

Application example 3

The method for correcting channel quality indication information provided in this application example is applicable to wireless communication systems, especially LTE-A (Long Term Evolution-Advanced, enhanced long-term evolution) systems. The following is a detailed introduction with specific examples. In the system of this example, the subframe of Femto (Home NodeB) is divided into almost blank subframe (ABS) and normal subframe, and the UE in this embodiment is R8/9UE.

In a heterogeneous network, if the low-power node is a CSG (Closed Subscribed Group, Closed Subscriber Group) Femto (home base station), then within the coverage of Femto, UEs that are not authorized to access Femto cannot access Femto , can only access other nodes (generally access high-power nodes with wide coverage). At this time, these UEs are strongly interfered by Femto, and it is difficult to normally receive signals from their access nodes. The R10 standard also introduces eICIC technology to solve this problem. By setting Femto ABS subframes (almost blank subframes, Almost Blank Subframe), UEs of other nodes within the Femto coverage area can operate in the subframe corresponding to the Femto ABS subframe. Data reception, more accurate measurement, etc. are performed on the frame. Obviously, on the normal subframe (non-ABS subframe) and ABS subframe of Femto, the power of Femto downlink transmission is completely different. Therefore, on the subframes of other nodes corresponding to different subframes, the Femto coverage The Femto interference received by UEs of other nodes within the range is also different, and their downlink channel quality and measurement results are also different. Step 301: UE calculates the downlink CQI measurement value according to the downlink channel estimation of several subframes, and calculates the CQI The measured value is fed back to the base station, and the base station receives the channel quality indicator (CQI) measured value reported by the terminal;

Step 302: the base station judges whether CQI information under different conditions is required and whether the terminal has the reporting capability of reporting CQI information under different conditions;

In step 302, the base station determines that the UE is an R8/9 UE, and then executes step 303; otherwise, directly selects a modulation scheme and a code rate according to the CQI information reported by the UE.

Step 303: the base station corrects and obtains the final CQI correction value of other node subframe sets corresponding to the Femto ABS subframe and other node subframe sets corresponding to the Femto normal subframe according to the CQI measurement value reported by the terminal;

Specifically perform the following operations:

(a) to carry out statistics;

为一个ACK/NACK统计周期内Femto ABS子帧所对应的其他节点子帧集合上位于Femto覆盖范围内某个的UE下行传输块的ACK数目和NACK数目；设定变量

为一个ACK/NACK统计周期内Femto正常子帧(非ABS子帧)所对应的其他节点子帧集合上位于Femto覆盖范围内某个UE下行传输块的ACK数目和NACK数目。set variable

It is the number of ACKs and NACKs of a certain UE downlink transmission block within the coverage of Femto on the subframe set of other nodes corresponding to the Femto ABS subframe in an ACK/NACK statistical period; set the variable

It is the number of ACKs and NACKs of a certain UE's downlink transmission block within the Femto coverage area on the subframe set of other nodes corresponding to the Femto normal subframe (non-ABS subframe) within an ACK/NACK statistical period.

清零；在每个ACK/NACK统计周期内，基站统计Femto ABS子帧所对应的其他节点子帧集合上某个UE下行传输块的ACK数目

和NACK数目

统计Femto正常子帧(非ABS子帧)所对应的其他节点子帧集合上某个UE下行传输块的ACK数目和NACK数目

The base station repeatedly performs statistics on the number of ACKs and the number of NACKs in units of ACK/NACK statistics period. At the beginning of each ACK/NACK statistical period, the variable

Cleared; in each ACK/NACK statistical period, the base station counts the number of ACKs of a certain UE downlink transmission block on the subframe set of other nodes corresponding to the Femto ABS subframe

and the number of NACKs

Count the number of ACKs of a certain UE downlink transmission block on the subframe set of other nodes corresponding to the Femto normal subframe (non-ABS subframe) and the number of NACKs

(b) Correction of measured values based on statistical results;

循环修正Femto ABS子帧所对应的其他节点子帧集合的信道质量指示，得到的Femto ABS子帧所对应的其他节点子帧集合调度终端前的最终修正信道质量信息

根据循环修正Femto非ABS子帧所对应的其他节点子帧集合的信道质量指示，得到的Femto非ABS子帧所对应的其他节点子帧集合调度终端前的最终修正信道质量信息

Before scheduling the terminal, the base station repeatedly corrects the corrected channel quality indication in units of ACK/NACK statistics period. At the end of each ACK/NACK statistical period, the base station, according to

Cyclically correct the channel quality indications of other node subframe sets corresponding to the Femto ABS subframe, and obtain the final corrected channel quality information before the terminal is scheduled for the other node subframe sets corresponding to the Femto ABS subframe

according to Cyclic correction of the channel quality indications of other node subframe sets corresponding to Femto non-ABS subframes, and the obtained final corrected channel quality information before the terminal is scheduled for other node subframe sets corresponding to Femto non-ABS subframes

(或

)和(或

)对信道质量指示信息的修正是结合各自的修正因子进行的，

(或

)的信道质量指示信息CQI修正因子为α，

(或

)的信道质量指示信息CQI修正因子为-β，那么UE的修正后Femto ABS子帧对应的其他节点的子帧集合的修正CQI更新如式子：In step (b),

(or

)and (or

) The correction of the channel quality indication information is carried out in combination with the respective correction factors,

(or

) channel quality indication information CQI correction factor is α,

(or

) channel quality indication information CQI correction factor is -β, then the revised CQI update of the subframe set of other nodes corresponding to the UE's revised Femto ABS subframe is as follows:

${\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; ACK</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; NACK</span>}}^{\mathrm{<span\; class="notranslate">\; ABS</span>}}<span\; class="notranslate">\; ,</span>$

The modified CQI update method of the subframe set of other nodes corresponding to the UE's corrected Femto normal subframe (non-ABS subframe) is similar, as follows:

${\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; 1</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; =</span>{\mathrm{<span\; class="notranslate">\; CQI</span>}}_{\mathrm{<span\; class="notranslate">\; mod</span>}\mathrm{<span\; class="notranslate">\; ify</span>}<span\; class="notranslate">\; ,</span>\mathrm{<span\; class="notranslate">\; i</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&alpha;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; ACK</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&beta;</span>}<span\; class="notranslate">\; *</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; NACK</span>}}^{\mathrm{<span\; class="notranslate">\; NoABS</span>}}<span\; class="notranslate">\; ,</span>$

为所述终端上报的CQI测量值CQI^measured。Among them, i represents the i-th correction, when i=0,

The CQI measured value CQI ^measured reported by the terminal.

(或

)和

(或

)对CQI修正因子设定为不同。如BLER要求为x，(或

)的CQI修正因子为α，

(或

)的CQI修正因子为-β，α和β都是正数，且满足α/β＝x/(1-x)。α and -β are correction factors, which can be flexibly set according to the specific application environment or experience during specific implementation. Preferably, in step (b), in order to achieve the target block error rate BLER, the

(or

)and

(or

) is set to be different for the CQI correction factor. If BLER requires x, (or

) CQI correction factor is α,

(or

) CQI correction factor is -β, α and β are both positive numbers, and satisfy α/β=x/(1-x).

选择Femto正常子帧(非ABS子帧)所对应的其他节点子帧集合的调制方式、码率等。Step 303: the base station according to the corrected channel quality information Select the modulation mode, code rate, etc. of other node subframe sets corresponding to the Femto ABS subframe; according to the corrected channel quality information

The modulation mode, code rate, etc. of the subframe set of other nodes corresponding to the Femto normal subframe (non-ABS subframe) are selected.

This example is applicable to the heterogeneous network of the LTE-A system. When the low-power node is a Femto of CSG (ClosedSubscribed Group, Closed Subscriber Group), UEs that are not authorized to access Femto within the coverage of Femto will introduce eICIC After the technology, the UE downlink channel quality indication information is amended. Compared with the existing method, this example can obtain better corrected CQI information, and can more effectively indicate the downlink channel quality of other node subframes corresponding to Femto ABS subframes and normal subframes (non-ABS subframes), Therefore, it is possible to select different modulation modes, code rates, etc. for the subframes of other nodes corresponding to Femto ABS subframes and normal subframes (non-ABS subframes) for UEs that are not authorized to access Femto within the coverage of Femto , to improve system throughput and efficiency.

In order to realize the foregoing method, the present invention also provides a base station, as shown in FIG. 3, the base station includes:

The CQI receiving module is used to receive the channel quality indication (CQI) measurement value reported by the terminal;

A capability judging module, configured to judge whether CQI information under different conditions is required and whether the terminal has the ability to report CQI information under different conditions;

A CQI correction module, configured to correct and obtain the final CQI correction value under different conditions according to the CQI measurement value reported by the terminal when it is judged that CQI information under different conditions is required and the terminal does not have the reporting capability;

The modulation selection module is configured to select a modulation mode and a code rate according to the final CQI correction value under the current corresponding conditions of the terminal when scheduling the terminal.

Specifically, the terminal without the capability is a terminal of the R8 version or the R9 version.

Further, the different conditions include:

A subframe set corresponding to a high-power node and/or a femto almost blank subframe (ABS) and a subframe set corresponding to a normal subframe at a high-power node; or, including:

A set of subframes corresponding to high power nodes and/or femto normal subframes; a set of subframes corresponding to high power nodes and/or femto zero power (Zero Power) subframes; and a high power node and/or femto reduced power (Reduced Power ) The subframe set corresponding to the subframe.

Preferably, as shown in Figure 4, the CQI correction module includes:

The statistics sub-module, under each condition, the number of ACKs and the number of NACKs of UE downlink transmission blocks reporting CQI measurement values within a predetermined statistical period;

The measurement value correction submodule, before scheduling the terminal, cyclically corrects the CQI measurement value reported by the terminal according to the ACK number and NACK number counted under each condition to obtain a final CQI correction value under the condition.

The measured value correction submodule corrects the CQI measured value according to the following formula:

分别为第i+1次和第i次修正后得到的CQI修正值，i＝0时，

为所述终端上报的CQI测量值，α和-β为修正因子，且满足α/β＝x/(1-x)，其中x为目标误块率。 ${\mathrm{CQI}}_{\mathrm{mod}\mathrm{ify}}^{i+1}={\mathrm{CQI}}_{\mathrm{mod}\mathrm{ify}}^i+\mathrm{\&alpha;}*N_{\mathrm{ACK}}-\mathrm{\&beta;}*N_{\mathrm{NACK}},$ in,

are the CQI correction values obtained after the i+1th and i-th corrections respectively, when i=0,

For the CQI measurement value reported by the terminal, α and -β are correction factors, and satisfy α/β=x/(1-x), where x is a target block error rate.

The method and the base station of the present invention respectively correct the channel quality indicator based on different conditions, and realize that the corrected channel quality indicator can reflect the channel quality under different conditions. Compared with the prior art, the method used in the present invention makes the corrected channel The quality indicator can correspond to the appropriate modulation mode and code rate under different conditions, thereby improving system throughput and system efficiency.

Those skilled in the art can understand that all or part of the steps in the above method can be completed by instructing relevant hardware through a program, and the program can be stored in a computer-readable storage medium, such as a read-only memory, a magnetic disk or an optical disk, and the like. Optionally, all or part of the steps in the foregoing embodiments may also be implemented using one or more integrated circuits. Correspondingly, each module in the foregoing embodiments may be implemented in the form of hardware, or may be implemented in the form of software function modules. The present invention is not limited to any specific combination of hardware and software.

Claims (10)

1. A method for selecting a modulation mode and a code rate based on a channel quality indicator is characterized by comprising the following steps:

a CQI receiving step, in which a base station receives a Channel Quality Indication (CQI) measured value reported by a terminal;

a capability judgment step, in which a base station judges whether CQI information under different conditions is required and whether the terminal has the reporting capability of reporting the CQI information under different conditions;

a CQI correction step, namely when the CQI information under different conditions is needed and the terminal does not have the reporting capability, the base station corrects the CQI information according to the CQI measured value reported by the terminal to obtain final CQI correction values under different conditions;

and a modulation selection step, wherein when the terminal is scheduled, the base station selects a modulation mode and a code rate according to the final CQI correction value under the current corresponding condition of the terminal.

2. The method of claim 1, wherein: and the terminal without the reporting capability is the terminal of the R8 version or the R9 version.

3. The method of claim 1, wherein: the different conditions include:

a subframe set corresponding to an Almost Blank Subframe (ABS) of the high-power node and/or femto and a subframe set corresponding to a normal subframe of the high-power node; or, comprising:

a subframe set corresponding to a high-power node and/or a femto normal subframe; a subframe set corresponding to a high Power node and/or femto Zero Power (Zero Power) subframe; and a subframe set corresponding to a high Power node and/or femto Reduced Power (Reduced Power) subframe.

4. The method of claim 1, wherein: the CQI correction step of obtaining final CQI correction values under different conditions comprises the following substeps:

a statistic substep, which is used for counting the ACK number and the NACK number of the UE downlink transmission blocks reporting the CQI measurement values in a preset statistic period under each condition;

and a measurement value correction substep, wherein before the terminal is scheduled, the CQI measurement value reported by the terminal is circularly corrected according to the ACK number and the NACK number to obtain a final CQI correction value under each condition.

5. The method of claim 4, wherein: in the measured value correcting substep, the CQI measured value is corrected according to the following formula:

<math> <mrow> <msubsup> <mi>CQI</mi> <mrow> <mi>mod</mi> <mi>ify</mi> </mrow> <mrow> <mi>i</mi> <mo>+</mo> <mn>1</mn> </mrow> </msubsup> <mo>=</mo> <msubsup> <mi>CQI</mi> <mrow> <mi>mod</mi> <mi>ify</mi> </mrow> <mi>i</mi> </msubsup> <mo>+</mo> <mi>&alpha;</mi> <mo>*</mo> <msub> <mi>N</mi> <mi>ACK</mi> </msub> <mo>-</mo> <mi>&beta;</mi> <mo>*</mo> <msub> <mi>N</mi> <mi>NACK</mi> </msub> <mo>,</mo> </mrow> </math> wherein,when the CQI correction values obtained after the i +1 th correction and the i-th correction are 0,

and for the CQI measured value reported by the terminal, alpha and beta are correction factors, and alpha/beta is x/(1-x), wherein x is a target block error rate.

6. A base station, comprising:

a CQI receiving module, configured to receive a Channel Quality Indicator (CQI) measurement value reported by a terminal;

the capability judging module is used for judging whether the CQI information under different conditions is needed or not and whether the terminal has the reporting capability of reporting the CQI information under different conditions or not;

the CQI correction module is used for correcting according to the CQI measured value reported by the terminal to obtain final CQI correction values under different conditions when the CQI information under different conditions is required and the terminal does not have the reporting capability;

and the modulation selection module is used for selecting a modulation mode and a code rate according to the final CQI correction value under the current corresponding condition of the terminal when the terminal is scheduled.

7. The base station of claim 6, wherein: terminals without such capability are terminals of version R8 or version R9.

8. The base station of claim 6, wherein:

the different conditions include:

a subframe set corresponding to an Almost Blank Subframe (ABS) of the high-power node and/or femto and a subframe set corresponding to a normal subframe of the high-power node; or, comprising:

a subframe set corresponding to a high-power node and/or a femto normal subframe; a subframe set corresponding to a high Power node and/or femto Zero Power (Zero Power) subframe; and a subframe set corresponding to a high Power node and/or femto Reduced Power (Reduced Power) subframe.

9. The base station of claim 6, wherein: the CQI correction module comprises:

the counting submodule counts the ACK number and the NACK number of the UE downlink transmission blocks reporting the CQI measurement values in a preset counting period under each condition;

and the measurement value correction submodule is used for circularly correcting the CQI measurement value reported by the terminal according to the ACK number and the NACK number counted under each condition to obtain a final CQI correction value under the condition before the terminal is scheduled.

10. The base station of claim 9, wherein: the measured value correcting submodule corrects the CQI measured value according to the following formula:

<math> <mrow> <msubsup> <mi>CQI</mi> <mrow> <mi>mod</mi> <mi>ify</mi> </mrow> <mrow> <mi>i</mi> <mo>+</mo> <mn>1</mn> </mrow> </msubsup> <mo>=</mo> <msubsup> <mi>CQI</mi> <mrow> <mi>mod</mi> <mi>ify</mi> </mrow> <mi>i</mi> </msubsup> <mo>+</mo> <mi>&alpha;</mi> <mo>*</mo> <msub> <mi>N</mi> <mi>ACK</mi> </msub> <mo>-</mo> <mi>&beta;</mi> <mo>*</mo> <msub> <mi>N</mi> <mi>NACK</mi> </msub> <mo>,</mo> </mrow> </math> wherein,

when the CQI correction values obtained after the i +1 th correction and the i-th correction are 0,

and for the CQI measured value reported by the terminal, alpha and beta are correction factors, and alpha/beta is x/(1-x), wherein x is a target block error rate.

Images