CN102546111A - CQI (Channel Quality Indicator) determining method and device thereof - Google Patents

Abstract

The invention discloses a CQI (Channel Quality Indicator) determining method and a device thereof and relates to the communication technology. After receiving a CQI value sent by UE (User Equipment) or obtaining the CQI value before revision of the current cycle according to the CQI value obtained through SRS (Sounding Reference Signal) measurement, a base station is firstly used for adjusting the CQI value before revision of the current cycle according to the revised CQI value of the last cycle, and then, other CQI values are adjusted according to specific conditions. Because the revised CQI value of the last cycle is referred, greater errors of the CQI value, caused by the reason that larger errors of the CQI reported by the UE or the CQI measured by the base station according to SRS appear or the base station misinterprets the CQI value reported by the UE and the like, are avoided, the accuracy of the revised CQI is improved on the basis of lower complexity, and system throughput is effectively improved on the basis of meeting system reliability.

Description

A kind of CQI confirms method and device

Technical field

The present invention relates to the communication technology, relate in particular to a kind of CQI and confirm method and device.

Background technology

Scheduling of resource and link adaptation techniques (mainly comprising Adaptive Modulation and Coding and MIMO mode switch) in LTE (Long Term Evolution, the Long Term Evolution) system are controlled by eNB (base station) fully.In up link; ENB is through SRS (Sounding Reference Signal; The reference measure symbol) measures link quality information SINR (Signal to Interference plus Noise Ratio, Signal to Interference plus Noise Ratio) value, come (User Equipment according to SINR then for UE; Subscriber equipment) selects adequate resources, modulation coding mode and transmission mode; In the down link, at first obtain CQI (Channel Quality Indicator, channel quality indication (CQI) information) in the UE side, and feed back to eNB by UE, eNB comes to select adequate resources, modulation coding mode and transmission mode for UE according to the CQI value of feedback then.

Usually, in order to describe for simplicity, unification is indicated the channel quality of up-downgoing with CQI, and wherein up CQI is meant the SINR value that SRS measures, and descending CQI is meant the CQI grade that the UE feedback obtains.

In real system, there is bigger error in the CQI value that UE reports or eNB measures, mainly contains the reason of following three aspects:

The one, when calculating sub-carrier signal-noise ratio, adopt account form is and during in practical application;

is then under low signal-to-noise ratio; Noise power accounts for leading role, thereby the CQI value that causes calculating is obviously higher;

The 2nd, the CQI that UE reports does not match with the demodulation performance of itself, and for example, though UE reports CQI=15, this moment, UE was if adopt CQI=15 can cause BLER (Block Error Ratio, bLock error rate, Block Error Rate) very high, and demodulation performance descends;

The 3rd, for descending; ENB can carry out reconstruct to the RI (order) of reporting of user, might report RI=2 by UE, and eNB then is judged to be RI=1; The PMI/CQI that this moment, UE reported is based on the RI=2 that measures and calculates, so eNB must revise the CQI that UE reports.

Because the performance and the CQI value of link circuit self-adapting have confidential relation, so the correctness of CQI value can directly influence the throughput of whole system.If eNB directly adopts the foundation of the CQI value of measurement as scheduling, can't satisfy QoS demand professional in the system this moment basically, therefore must revise the CQI value that measures, and could guarantee the work of system stability.

At present, carrying out the method that CQI revises is according to the ACK/NACK information that the UE feedback obtains CQI to be revised.

Before introducing the CQI correction algorithm, define following variable earlier:

CQI _InThe CQI index value that the decoding of expression base station obtains; CQI _OutThe CQI index value that obtains after the expression base station is revised; CQI _AddExpression accumulative total CQI index adjustment amount; Min and Max represent minimum maximum adjusting range respectively; K and step are that CQI revises the adjustment parameter, confirm specifically to adjust parameter according to target BLER value, for example during BLER=10%, make K=9, step=0.05.

When obtaining new CQI, as shown in Figure 1, the method for carrying out the CQI correction comprises:

Step S101, initialization CQI _Add=0;

Step S102, judge whether the ACK/NACK information of this reception is first transmission; If first transmission, execution in step S103 revises otherwise finish CQI;

Step S103, if through this error of transmission of CRC check judgement and CQI _Add＞Min is then with CQI _AddAdjust K step-length, i.e. CQI downwards _Add=CQI _Add-K*step; If judge the correct and CQI of this transmission through CRC check _Add＜Max is then with CQI _AddAdjust upward step-length, i.e. a CQI _Add=CQI _Add+ step;

The CQI of step S104, restriction adjustment _AddScope; If CQI _Add＞Max then makes CQI _Add=Max; If CQI _Add＜Min then makes CQI _Add=Min;

Step S105, renewal revised CQI output valve: CQI _Out=CQI _In+ CQI _Add

The physical significance of this algorithm is if the NACK of feedback is too much, and it is higher to show that then CQI estimates, adjusts the CQI value downwards; Otherwise it is on the low side to show that then CQI estimates, adjusts upward the CQI value.

Though this CQI confirms CQI accuracy that method reports at UE and can the CQI value be adjusted to suitable value according to ACK/NACK information when higher; When but the CQI that UE reports occurs translating the CQI value that wrong UE reports than mistake or base station; Can cause the CQI value in former and later two CQI cycles to change greatly, thereby cause the unstable properties of AMC on the one hand, the CQI correction algorithm can occur than large deviation on the other hand; CQI value in this cycle is insincere basically, and throughput performance can reduce.

Summary of the invention

The embodiment of the invention provides a kind of CQI to confirm method and device, with the revised CQI accuracy of raising on the basis that is implemented in lower complexity, thereby is satisfying effective elevator system throughput on the basis of system reliability.

A kind of CQI confirms method, comprising:

Receive the CQI value of UE transmission or carry out the SRS measurement, CQI value before the correction of acquisition current period;

According to CQI value after the correction in last cycle, CQI value before the correction of said current period is adjusted;

Confirm that adjusted CQI value is CQI value after the correction in current cycle.

A kind of CQI confirms device, comprising:

Obtain the unit, be used to receive the CQI value of UE transmission or carry out the SRS measurement, CQI value before the correction of acquisition current period;

Adjustment unit, the user based on the correction in last cycle after the CQI value, CQI value before the correction of said current period is adjusted;

Determining unit is used for confirming that adjusted CQI value is a CQI value after the correction in current cycle.

The embodiment of the invention provides a kind of CQI to confirm method and device; The CQI value that the base station perhaps measures according to SRS in the CQI value that receives the UE transmission; After obtaining the preceding CQI value of correction of current period; Earlier according to CQI value after the correction in last cycle; CQI value before the correction of current period is adjusted, carried out other CQI adjustment more as the case may be.Because with reference to CQI value after the correction in last cycle; The CQI value that CQI that has avoided reporting owing to UE or base station are measured according to SRS occurs translating CQI value appearance that reasons such as CQI value that wrong UE reports cause than serious mistake than mistake or base station; And then be implemented in and improve revised CQI accuracy on the basis of lower complexity, satisfying on the basis of system reliability effectively elevator system throughput.

Description of drawings

Fig. 1 is a CQI method of adjustment flow chart in the prior art;

Fig. 2 a is that the CQI that the embodiment of the invention provides confirms method flow diagram;

Fig. 2 b is the CQI adjustment parameters relationship sketch map that the embodiment of the invention provides;

Fig. 3 confirms method flow diagram for a kind of preferable CQI that the embodiment of the invention provides;

The CQI that Fig. 4 provides for the embodiment of the invention confirms the apparatus structure sketch map.

Embodiment

The embodiment of the invention provides a kind of CQI to confirm method and device; The CQI value that the base station perhaps measures according to SRS in the CQI value that receives the UE transmission; After obtaining the preceding CQI value of correction of current period; Earlier according to CQI value after the correction in last cycle; CQI value before the correction of current period is adjusted, carried out other CQI adjustment more as the case may be.Because with reference to CQI value after the correction in last cycle; The CQI value that CQI that has avoided reporting owing to UE or base station are measured according to SRS occurs translating CQI value appearance that reasons such as CQI value that wrong UE reports cause than serious mistake than mistake or base station; And then be implemented in and improve revised CQI accuracy on the basis of lower complexity, satisfying on the basis of system reliability effectively elevator system throughput.

Shown in Fig. 2 a, the CQI that the embodiment of the invention provides confirms that method comprises:

The CQI value that step S201, reception UE send is perhaps carried out SRS and is measured the preceding CQI value of the correction of acquisition current period;

Step S202, based on CQI value after the correction in last cycle, CQI value before the correction of current period is adjusted;

Step S203, confirm that adjusted CQI value is CQI value after the correction in current cycle.

Owing to adjusted CQI value before the correction of current period according to CQI value after the correction in last cycle, so even the preceding CQI value of the correction of current period has than serious mistake, the revised CQI accuracy of raising that also can be by a relatively large margin.

In order further to improve the adjustment precision of CQI value; Can select adjusting range according to the gap of CQI value after the correction in CQI value and last cycle before the correction of current period, concrete, according to CQI value after the correction in last cycle; CQI value before the correction of current period is adjusted, is specifically comprised:

When confirming before the correction of current period after the CQI value and the correction in last cycle that the absolute value of CQI value difference value is less than or equal to predefined first threshold, be that the main reference value is adjusted with CQI value before the correction of current period;

When confirming that the absolute value of CQI value difference value is greater than predefined first threshold after the CQI value and the correction in last cycle before the correction of current period, the CQI value is adjusted for the main reference value after the correction of former one-period.

For example, adjustment weights p can be set,, then confirm adjusted CQI value CQI as if being that the main reference value is adjusted with CQI value before the correction of current period _InFor:

If the CQI value was adjusted for the main reference value after the correction of one-period in the past, then confirm adjusted CQI value CQI _InFor:

Wherein, CQI _In ^T1Be CQI value before the correction of current period, CQI _Out ^T0Be CQI value after the correction in last cycle, p is predefined adjustment weights, and p＞0.5.

The p value can and be carried out SRS and measure the perhaps Cycle Length setting of UE transmission CQI value based on user moving speed; When the cycle of carrying out SRS measurement or UE transmission CQI value is longer; Make that then the weights of CQI value are bigger before the correction of current period, when carry out that SRS measures or the cycle of UE transmission CQI value more in short-term, make that then the weights of CQI value are bigger after the correction in last cycle; If user moving speed is bigger; Make that then the weights of CQI value are bigger before the correction of current period, less as if user moving speed, make that then the weights of CQI value are bigger after the correction in last cycle.

Wherein, CQI _In ^T1, CQI _Out ^T0, CQI _In ^T0And CQI _Out ^T1Relation shown in Fig. 2 b, when a CQI adjustment cycle was initial, the CQI value of acquisition was CQI _In, when a CQI adjustment cycle finished, the CQI value that obtains after the adjustment was CQI _Out

Certainly, CQI value after according to the correction in last cycle, after the CQI value is adjusted before the correction of current period, further adjustment CQI value:

When obtaining new CQI value; Initialization CQI adjusted value is 0; The CQI adjusted value is an intermediate parameters that is used to adjust CQI; When the ACK/NACK message of confirming this reception is the message of first transmission, if through CRC check this error of transmission of judgement and CQI adjusted value greater than predefined minimum adjusted value, then the CQI adjusted value is adjusted K step-length downwards; If through CRC check judge this transmission correctly and the CQI adjusted value less than the highest predefined adjusted value; Then the CQI adjusted value is adjusted upward a step-length; The CQI adjusted value is not adjusted in other cases, wherein, the highest adjusted value is greater than minimum adjusted value; At this moment, confirm adjusted CQI value CQI _OutFor: according to CQI value after the correction in last cycle to the correction of current period before CQI value the CQI value and the CQI adjusted value sum that obtain after adjusting.

After the CQI adjusted value was adjusted K step-length downwards, the CQI adjusted value was then set the CQI adjusted value and is equaled predefined minimum adjusted value less than predefined minimum adjusted value, otherwise kept current C QI adjusted value;

After the CQI adjusted value was adjusted upward a step-length, the CQI adjusted value was then set the CQI adjusted value and is equaled the highest predefined adjusted value greater than the highest predefined adjusted value, otherwise kept current C QI adjusted value.

Concrete, the preferable CQI that the embodiment of the invention provides confirms that method is as shown in Figure 3, comprising:

The CQI value that step S301, reception UE send is perhaps carried out SRS and is measured the preceding CQI value of the correction of acquisition current period;

Whether the absolute value of CQI value difference value is less than or equal to predefined first threshold after step S302, the preceding CQI value of correction of judging current period and the correction in last cycle, if, execution in step S303, otherwise execution in step S304;

Step S303, confirm adjusted CQI value CQI _InFor:

Step S304, confirm adjusted CQI value CQI _InFor:

Step S305, judge that whether the ACK/NACK message of this reception be the message of first transmission, if, execution in step S307, otherwise execution in step S306;

Step S306 confirms that adjusted CQI value is CQI value after the correction in current cycle, and finishes CQI adjustment flow process;

Step S307, if through this error of transmission of CRC check judgement and CQI adjusted value greater than predefined minimum adjusted value, then the CQI adjusted value is adjusted K step-length downwards; If through CRC check judge this transmission correctly and the CQI adjusted value less than the highest predefined adjusted value, then the CQI adjusted value is adjusted upward a step-length;

Step S308, if after the CQI adjusted value adjusted K step-length downwards, the CQI adjusted value was then set the CQI adjusted value and is equaled predefined minimum adjusted value less than predefined minimum adjusted value; After the CQI adjusted value was adjusted upward a step-length, the CQI adjusted value was then set the CQI adjusted value and is equaled the highest predefined adjusted value greater than the highest predefined adjusted value;

Step S309, confirm that adjusted CQI value is: based on CQI value and the CQI adjusted value sum of CQI value adjustment after the correction in last cycle, and end CQI adjusts flow process.

The embodiment of the invention is also corresponding to provide a kind of CQI to confirm device, as shown in Figure 4, comprises in this device:

Obtain unit 401, be used to receive the CQI value of UE transmission or carry out the SRS measurement, CQI value before the correction of acquisition current period;

Adjustment unit 402, the user based on the correction in last cycle after the CQI value, CQI value before the correction of current period is adjusted;

Determining unit 403 is used for confirming that adjusted CQI value is a CQI value after the correction in current cycle.

Wherein, adjustment unit 402 specifically is used for:

When confirming before the correction of current period after the CQI value and the correction in last cycle that the absolute value of CQI value difference value is less than or equal to predefined first threshold, be that the main reference value is adjusted with CQI value before the correction of current period;

When confirming that the absolute value of CQI value difference value is greater than predefined first threshold after the CQI value and the correction in last cycle before the correction of current period, the CQI value is adjusted for the main reference value after the correction of former one-period.

Adjustment unit 402 with the correction of current period before the CQI value be that the main reference value is adjusted, specifically comprise: confirm adjusted CQI value CQI _InFor:

Before the adjustment unit 402 after the correction of one-periods the CQI value adjust for the main reference value, specifically comprise: confirm adjusted CQI value CQI _InFor:

Wherein, CQI _In ^T1Be CQI value before the correction of current period, CQI _Out ^T0Be CQI value after the correction in last cycle, p is predefined adjustment weights, and p＞0.5.

Adjustment unit 402 also is used for:

CQI value after according to the correction in last cycle; After the CQI value is adjusted before the correction of current period; When the ACK/NACK message of confirming this reception is the message of first transmission; Greater than predefined minimum adjusted value, then the CQI adjusted value is adjusted K step-length downwards as if judge this error of transmission and CQI adjusted value through CRC check; If through CRC check judge this transmission correctly and the CQI adjusted value less than the highest predefined adjusted value, then the CQI adjusted value is adjusted upward a step-length;

Confirm adjusted CQI value CQI _OutFor: according to CQI value after the correction in last cycle to the correction of said current period before CQI value the CQI value and the CQI adjusted value sum that obtain after adjusting.

The embodiment of the invention provides a kind of CQI to confirm method and device; The CQI value that the base station perhaps measures according to SRS in the CQI value that receives the UE transmission; After obtaining the preceding CQI value of correction of current period; Earlier according to CQI value after the correction in last cycle; CQI value before the correction of current period is adjusted, carried out other CQI adjustment more as the case may be.Because with reference to CQI value after the correction in last cycle; The CQI value that CQI that has avoided reporting owing to UE or base station are measured according to SRS occurs translating CQI value appearance that reasons such as CQI value that wrong UE reports cause than serious mistake than mistake or base station; And then be implemented in and improve revised CQI accuracy on the basis of lower complexity, satisfying on the basis of system reliability effectively elevator system throughput.

Those skilled in the art should understand that embodiments of the invention can be provided as method, system or computer program.Therefore, the present invention can adopt the form of the embodiment of complete hardware embodiment, complete software implementation example or combination software and hardware aspect.And the present invention can be employed in the form that one or more computer-usable storage medium (including but not limited to magnetic disc store, CD-ROM, optical memory etc.) that wherein include computer usable program code go up the computer program of implementing.

The present invention is that reference is described according to the flow chart and/or the block diagram of method, equipment (system) and the computer program of the embodiment of the invention.Should understand can be by the flow process in each flow process in computer program instructions realization flow figure and/or the block diagram and/or square frame and flow chart and/or the block diagram and/or the combination of square frame.Can provide these computer program instructions to the processor of all-purpose computer, special-purpose computer, Embedded Processor or other programmable data processing device to produce a machine, make the instruction of carrying out through the processor of computer or other programmable data processing device produce to be used for the device of the function that is implemented in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame appointments.

These computer program instructions also can be stored in ability vectoring computer or the computer-readable memory of other programmable data processing device with ad hoc fashion work; Make the instruction that is stored in this computer-readable memory produce the manufacture that comprises command device, this command device is implemented in the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.

These computer program instructions also can be loaded on computer or other programmable data processing device; Make on computer or other programmable devices and to carry out the sequence of operations step producing computer implemented processing, thereby the instruction of on computer or other programmable devices, carrying out is provided for being implemented in the step of the function of appointment in flow process of flow chart or a plurality of flow process and/or square frame of block diagram or a plurality of square frame.

Although described the preferred embodiments of the present invention, in a single day those skilled in the art get the basic inventive concept could of cicada, then can make other change and modification to these embodiment.So accompanying claims is intended to be interpreted as all changes and the modification that comprises preferred embodiment and fall into the scope of the invention.

Obviously, those skilled in the art can carry out various changes and modification to the present invention and not break away from the spirit and scope of the present invention.Like this, belong within the scope of claim of the present invention and equivalent technologies thereof if of the present invention these are revised with modification, then the present invention also is intended to comprise these changes and modification interior.

Claims (10)

1. a CQI confirms method, it is characterized in that, comprising:

Receive the CQI value of UE transmission or carry out the SRS measurement, CQI value before the correction of acquisition current period;

According to CQI value after the correction in last cycle, CQI value before the correction of said current period is adjusted;

Confirm that adjusted CQI value is CQI value after the correction in current cycle.

2. the method for claim 1 is characterized in that, and is said according to CQI value after the correction in last cycle, and CQI value before the correction of said current period is adjusted, and specifically comprises:

When confirming before the correction of current period after the CQI value and the correction in last cycle that the absolute value of CQI value difference value is less than or equal to predefined first threshold, be that the main reference value is adjusted with CQI value before the correction of current period;

When confirming that the absolute value of CQI value difference value is greater than predefined first threshold after the CQI value and the correction in last cycle before the correction of current period, the CQI value is adjusted for the main reference value after the correction of former one-period.

3. method as claimed in claim 2 is characterized in that, said is that the main reference value is adjusted with CQI value before the correction of current period, specifically comprises: confirm adjusted CQI value CQI _InFor:

${\mathrm{CQI}}_{\mathrm{in}}=p\·{\mathrm{CQI}}_{\mathrm{in}}^{t_1}+(1-p)\·{\mathrm{CQI}}_{\mathrm{out}}^{t_0};$

The CQI value is adjusted for the main reference value after the correction of said one-period in the past, specifically comprises: confirm adjusted CQI value CQI _InFor: ${\mathrm{CQI}}_{\mathrm{In}}=(1-p)\·{\mathrm{CQI}}_{\mathrm{In}}^{t_1}+p\·{\mathrm{CQI}}_{\mathrm{Out}}^{t_0};$

Wherein, CQI _In ^T1Be CQI value before the correction of current period, CQI _Out ^T0Be CQI value after the correction in last cycle, p is predefined adjustment weights, and p＞0.5.

4. method as claimed in claim 3 is characterized in that, said p value is according to user moving speed and carry out the SRS measurement or the Cycle Length setting of UE transmission CQI value.

5. the method for claim 1 is characterized in that, CQI value after based on the correction in last cycle after the CQI value is adjusted before the correction of said current period, also comprises:

When the ACK/NACK message of confirming this reception is the message of first transmission, if through CRC check this error of transmission of judgement and CQI adjusted value greater than predefined minimum adjusted value, then the CQI adjusted value is adjusted K step-length downwards; If through CRC check judge this transmission correctly and the CQI adjusted value less than the highest predefined adjusted value, then the CQI adjusted value is adjusted upward a step-length, the CQI adjusted value is not adjusted in other cases;

Confirm adjusted CQI value CQI _OutFor: according to CQI value after the correction in last cycle to the correction of said current period before CQI value the CQI value and the CQI adjusted value sum that obtain after adjusting.

6. method as claimed in claim 5 is characterized in that, also comprises:

After the CQI adjusted value was adjusted K step-length downwards, said CQI adjusted value was then set said CQI adjusted value and is equaled predefined minimum adjusted value less than predefined minimum adjusted value, otherwise kept current C QI adjusted value;

After the CQI adjusted value was adjusted upward a step-length, said CQI adjusted value was then set said CQI adjusted value and is equaled the highest predefined adjusted value greater than the highest predefined adjusted value, otherwise kept current C QI adjusted value.

7. a CQI confirms device, it is characterized in that, comprising:

Obtain the unit, be used to receive the CQI value of UE transmission or carry out the SRS measurement, CQI value before the correction of acquisition current period;

Adjustment unit, the user based on the correction in last cycle after the CQI value, CQI value before the correction of said current period is adjusted;

Determining unit is used for confirming that adjusted CQI value is a CQI value after the correction in current cycle.

8. device as claimed in claim 7 is characterized in that, said adjustment unit specifically is used for:

When confirming before the correction of current period after the CQI value and the correction in last cycle that the absolute value of CQI value difference value is less than or equal to predefined first threshold, be that the main reference value is adjusted with CQI value before the correction of current period;

When confirming that the absolute value of CQI value difference value is greater than predefined first threshold after the CQI value and the correction in last cycle before the correction of current period, the CQI value is adjusted for the main reference value after the correction of former one-period.

9. device as claimed in claim 8 is characterized in that, said adjustment unit with the correction of current period before the CQI value be that the main reference value is adjusted, specifically comprise: confirm adjusted CQI value CQI _InFor: ${\mathrm{CQI}}_{\mathrm{In}}=p\·{\mathrm{CQI}}_{\mathrm{In}}^{t_1}+(1-p)\·{\mathrm{CQI}}_{\mathrm{Out}}^{t_0};$

Before the said adjustment unit after the correction of one-period the CQI value adjust for the main reference value, specifically comprise: confirm adjusted CQI value CQI _InFor:

Wherein, CQI _In ^T1Be CQI value before the correction of current period, CQI _Out ^T0Be CQI value after the correction in last cycle, p is predefined adjustment weights, and p＞0.5.

10. device as claimed in claim 7 is characterized in that, said adjustment unit also is used for:

CQI value after according to the correction in last cycle; After the CQI value is adjusted before the correction of said current period; When the ACK/NACK message of confirming this reception is the message of first transmission; Greater than predefined minimum adjusted value, then the CQI adjusted value is adjusted K step-length downwards as if judge this error of transmission and CQI adjusted value through CRC check; If through CRC check judge this transmission correctly and the CQI adjusted value less than the highest predefined adjusted value, then the CQI adjusted value is adjusted upward a step-length, the CQI adjusted value is not adjusted in other cases;

Confirm adjusted CQI value CQI _OutFor: according to CQI value after the correction in last cycle to the correction of said current period before CQI value the CQI value and the CQI adjusted value sum that obtain after adjusting.

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