CN102761397A - CQI regulation method, device and system - Google Patents

Abstract

The invention provides a channel quality indication (CQI) regulation method, device and system. The method comprises the following steps: determining wireless environment parameters by a base station NodeB; determining environment correction factors by the NodeB according to the wireless environment parameters; and adjusting CQI reported by UE by the NodeB according to the environment correction factors. According to the invention, the adjusted CQI can accurately show channel quality.

Description

A kind of method of adjustment of channel quality indicator (CQI), device and system

Technical field

The present invention relates to moving communicating field, relate in particular to a kind of method of adjustment, device and system of channel quality indicator (CQI).

Background technology

At present, in the TD-HSDPA GSM, channel quality indication (CQI) is the important feedback information that subscriber equipment (UE) reports base station (NodeB), is used to indicate current channel quality.When the CQI of UE feedback can reflect current channel quality comparatively exactly, when promptly the accuracy of CQI is higher, can guarantee less Block Error Rate (BLER) and bigger systematic functions such as throughput of system.

At present, UE carries out channel estimating through the RSCP/ISCP that measures P-CCPCH, and according to estimated result, UE chooses appropriate C QI according to known HS-PDSCH resource allocation status, and (HS-SICH) feeds back to NodeB with the CQI that chooses through ascending control channel.

According to current agreement; The value of CQI from 1 to 63; The data block size that each CQI value is corresponding different; UE chooses initial CQI value according to the ability rating of self, and NodeB adopts predetermined correction step-length (StepSize) that the CQI value is revised according to actual Block Error Rate then, to adapt to the variation of wireless environment.

Particularly, NodeB is at the CQI that receives that UE sends, and after initially BLER was updated, the fixing StepSize of employing upgraded CQI deviation (CQI _Offset), and with the CQI after upgrading _OffsetCQI to the UE feedback compensates.Modulation format (RMF) and transmission block size (RTBS) that NodeB recommends according to the CQI after compensating, decision transformat and transmission block size next time.

Wherein, CQI _OffsetMode according to following is upgraded:

When initial BLER＜target BLER * 10 ^-Δ/10The time:

CQI _offset(n)＝CQI _offset(n-1)+StepSize

When initial BLER＞target BLER * 10 ^-Δ/10The time:

CQI _offset(n)＝CQI _offset(n-1)-StepSize

Under other situation:

CQI _offset(n)＝CQI _offset(n-1)

It is thus clear that there is following defective: CQI in existing C QI method of adjustment _OffsetCorrection step-length (StepSize) be constant because the complexity of wireless environment, fixing correction step-length can't reflect channel status truly, therefore causes the accuracy of CQI lower, systematic functions such as Block Error Rate and throughput of system can't guarantee.

Summary of the invention

In view of this, the invention provides a kind of method of adjustment, device and system of channel quality indicator (CQI), so that make adjusted CQI can reflect channel quality exactly.

The technical scheme that the present invention adopts specifically is achieved in that

A kind of method of adjustment of channel quality indicator (CQI), this method comprises:

Base station NodeB is confirmed the wireless environment parameter;

NodeB confirms the environmental correction factor according to said wireless environment parameter;

NodeB adjusts according to the CQI that said environmental correction factor pair UE reports.

A kind of adjusting device of channel quality indicator (CQI) is arranged in NodeB, and this device comprises environmental parameter determination module, environmental correction factor determination module and adjusting module;

Said environmental parameter determination module is used for confirming the wireless environment parameter;

Said environmental correction factor determination module is used for confirming the environmental correction factor according to said wireless environment parameter;

Said adjusting module is used for adjusting according to the CQI that said environmental correction factor pair UE reports.

A kind of Adjustment System of channel quality indicator (CQI), this system comprises NodeB and UE;

Said UE is used for reporting CQI to said NodeB;

Said NodeB is used for confirming according to the wireless environment parameter environmental correction factor of CQI, and the CQI that reports according to the said UE of said environmental correction factor pair adjusts.

Visible by technique scheme; The present invention is through confirming the environmental correction factor of CQI according to the wireless environment parameter; Can utilize the correction step-length of environmental correction factor pair CQI to adjust according to the wireless environment variation situation of UE; Make to adapt to the variation of UE wireless environment, thereby make adjusted CQI can reflect channel quality exactly the erection rate of CQI.

Description of drawings

Fig. 1 is a CQI method of adjustment flow chart provided by the invention.

Fig. 2 is NodeB provided by the invention dynamically adjusts CQI according to wireless environment and cover type a method flow diagram.

Fig. 3 is the adjusting device structure chart of channel quality indicator (CQI) provided by the invention.

Fig. 4 is that the Adjustment System of channel quality indicator (CQI) provided by the invention is formed sketch map.

Embodiment

With the fixing correction step-length of available technology adopting the CQI of UE feedback is adjusted and to compare; The present invention confirms the environmental correction factor according to the wireless environment parameter; Utilize the correction step-length of this environmental correction factor pair CQI to adjust; Make this correction step-length can adapt to the variation of UE wireless environment, thereby the CQI of UE feedback is realized dynamically adjustment, make it can reflect the channel quality of UE exactly.

Fig. 1 is a CQI method of adjustment flow chart provided by the invention.

As shown in Figure 1, this method comprises:

Step 101, base station NodeB are confirmed the wireless environment parameter.

Step 102, NodeB confirms the environmental correction factor according to the wireless environment parameter.

Step 103, NodeB adjusts according to the CQI of the said UE feedback of said environmental correction factor pair.

In method shown in Figure 1,, therefore confirm the environmental correction factor according to the wireless environment parameter because the wireless environment parameter of UE can reflect the wireless environment variation speed of UE; Can be so that can adapt to the variation of wireless environment to the adjustment of CQI, for example, when the wireless environment variation of UE is very fast; Utilize the correction step-length of environmental correction factor pair CQI to adjust, make it get bigger value, and then accelerate adjustment CQI; When the wireless environment variation of UE is slow; Utilize the correction step-length of environmental correction factor pair CQI to adjust, make it get less value, and then slow down the adjustment of CQI.

Wherein, The wireless environment parameter can comprise total received power in broadband (the Received Total Wideband Power of NodeB; RTWP) and interference signal code received power (Interference on Siganal Code Power; ISCP), promptly adopt RTWP and ISCP to weigh the wireless environment variation situation of UE.At present, the RTWP and the ISCP of these NodeB reception data in each time slot of NodeB general measure.

When the CQI according to environmental correction factor pair UE feedback adjusts,, specifically can adopt following scheme that the CQI that UE feeds back is adjusted in order to change existing C QI adjustment scheme less as far as possible:

Block error rate BLER according to this UE adopts the predetermined step-length CQI deviation CQI last to this UE that revise _OffsetAdjust, utilize said environmental correction factor pair adjustment result further to adjust again and obtain the current CQI of this UE _Offset, utilize the current CQI of this UE _OffsetCQI to this UE feedback adjusts.

Confirm the speed of the environmental correction factor in order to accelerate the NodeB side, can store the value of the wireless environment parameter and the environmental correction factor in the NodeB side in advance, NodeB searches corresponding environmental correction factor value according to the wireless environment parameter then.

Particularly; In advance the wireless environment parameter is divided into different grade; Calculate the corresponding environmental correction factor value of each grade wireless environment parameter respectively, store wireless environment parameters'grade relation then, and the corresponding relation between wireless environment parameter grade and the environmental correction factor value; NodeB obtains the wireless environment parameter, confirms this wireless environment parameter corresponding grades, searches the corresponding environmental correction factor value of this grade.

In addition; The applicant finds after deliberation; Have corresponding relation between the cover type of wireless environment values of parameters and NodeB, in order further to accelerate the speed that the NodeB side is confirmed the environmental correction factor, the applicant proposes; Corresponding relation in NodeB between storage wireless environment parameter grade, cover type and the environmental correction factor; When the definite environmental correction factor, directly search wireless environment parameter grade and the corresponding relation between the environmental correction factor under this NodeB self cover type, and needn't search wireless environment parameter grade and the corresponding relation between the environmental correction factor under other cover types; Owing to dwindled seek scope, therefore can improve seek rate.

Take a concrete example below exemplary illustration is carried out in CQI bearing calibration provided by the invention, the son of giving an example is not limited to the present invention.

Fig. 2 is NodeB provided by the invention dynamically adjusts CQI according to wireless environment and cover type a method flow diagram.

As shown in Figure 2, this method comprises:

Step 201, NodeB obtains the CQI that UE reports.

In this step, UE carries out channel estimating through the RSCP/ISCP that measures P-CCPCH.According to estimated result, UE chooses appropriate C QI according to known HS-PDSCH resource allocation status and feeds back to NodeB through ascending control channel (HS-SICH).

Step 202, NodeB utilizes moving average to obtain the average CQI of this UE.

According to present PF dispatching algorithm, NodeB need do moving average to the CQI that receives from UE, particularly, can adopt following formula that CQI is done moving average:

$\stackrel{\‾}{{\mathrm{CQI}}_i\left(n\right)}=(1-\frac{1}{T_1})\stackrel{\‾}{{\mathrm{CQI}}_i(n-1)}+\frac{1}{T_1}{\mathrm{CQI}}_i\left(n\right)$

Wherein, the span of T1 is [10,1999], and the value of T1 should be followed following principle: the T1 long enough, so that can filter the influence that declines soon; T1 also will enough lack, so that can keep the influence that declines slowly.

Step 203, NodeB calculates initial BLER value.

When calculating initial BLER value, relate to following notion: measurement period T, judge once in each measurement period T whether initial BLER needs renewal; Minimum hits N _{Min_sample}, mistake piece counts N _{Min_error}, total hits N _{Total_sample}Count N with total wrong piece _{Total_error}, when finish each measuring period, if should interior N of cycle _{Total_sample}Greater than N _{Min_sample}Perhaps N _{Total_error}Greater than N _{Min_error}, then initial BLER is updated to N _{Total_error}/ N _{Total_sample}, and according to CQI provided by the invention _OffsetUpdate method is upgraded CQI _Offset, otherwise to initial BLER and CQI _OffsetDo not do renewal.

Step 204, NodeB obtains the environmental correction factor (Delta_CQI_Env).

In this step, obtain Delta_CQI_Env according to RTWP and ISCP and cover type.

Particularly,, in advance ISCP and RTWP are turned to 4 grades of branch according to influence to channel quality, be respectively [108 ,-100], (100 ,-90], (90 ,-80] and (80 ,-70], and give corresponding weights 2,1 ,-1 and-2.Environmental correction factor D elta_CQI_Env is obtained by formula (1).

Delta_CQI_Env＝|_0.8×ISCP+0.2×RTWP+0.5_| (1)

Wherein, | _ 0.8 * ISCP+0.2 * RTWP+0.5_| representes the result of 0.8 * ISCP+0.2 * RTWP+0.5 is rounded downwards.Wherein, ISCP and the RTWP weighted value in formula (1) can be adjusted according to the actual conditions such as certainty of measurement of ISCP and RTWP.

According to the result of calculation of formula (1),, can obtain table one according to the relation of wireless environment parameter and cover type:

Table one

NodeB confirms the value of RTWP and the value corresponding grades of ISCP after obtaining RTWP and ISCP, inquire about the corresponding environmental correction factor value of said grade under this NodeB cover type.

Step 205, NodeB according to Delta_CQI_Env to CQI deviation (CQI _Offset) dynamically adjust.

In this step, introduce the dynamic CQI relevant with wireless environment _OffsetAdjustment mechanism makes CQI adjustment mobilism, adjustment and the ascending idle port quality of CQI organically combined with the NodeB cover type, thereby realization CQI reacts the situation of whole wireless environment more accurately.CQI _OffsetDynamically adjustment algorithm is following:

When initial BLER＜target BLER * 10 ^-Δ/10The time:

CQI _offset(n)＝CQI _offset(n-1)+StepSize+Delta_CQI_Env

When initial BLER＞target BLER * 10 ^-Δ/10The time:

CQI _offset(n)＝CQI _offset(n-1)-StepSize+Delta_CQI_Env

Under other situation:

CQI _offset(n)＝CQI _offset(n-1)

Wherein, StepSize is the correction step-length of presetting.When initial BLER is not less than target BLER * 10 ^-Δ/10And be not more than target BLER * 10 ^-Δ/10The time, CQI _OffsetRemain unchanged.Can also be CQI _OffsetBound is set, when its bound all is set to 0, explains that initial BLER controlled function closes.

Wherein, CQI _OffsetThe scope that also has bound if its bound all is set as 0, explains that then initial BLER controlled function closes.

Step 206, NodeB is according to adjusted CQI _OffsetThe CQI that UE is reported compensates.

In this step, NodeB is through adding CQI on the CQI basis that reports at UE _OffsetThe CQI that UE is reported compensates.

After the CQI that NodeB reports UE compensates, can utilize the RMF of the CQI adjustment UE after the compensation.

The present invention introduces the environmental correction factor according to cover type and wireless environment parameter; Realized that the CQI that UE is reported carries out dynamic adjustments; Remedy prior art and adopt the fixing step-length of revising; The defective that can not fully reflect radio channel state and coverage mode can reduce the interference of eating dishes without rice or wine of TD-HSDPA system, and can generally improve the HSDPA data BLER of UE and improve transmission rate.

According to said method, the present invention also provides corresponding adjusting device and system, specifically sees also Fig. 3-Fig. 4.

Fig. 3 is the adjusting device structure chart of channel quality indicator (CQI) provided by the invention.

As shown in Figure 3, this device comprises environmental parameter determination module 301, environmental correction factor determination module 302 and adjusting module 303.

Environmental parameter determination module 301 is used for confirming the wireless environment parameter.

Environmental correction factor determination module 302 is used for confirming the environmental correction factor according to said wireless environment parameter.

Adjusting module 303 is used for adjusting according to the CQI that said environmental correction factor pair UE reports.

Wherein, environmental parameter determination module 301 is used for confirming bandwidth total received power RTWP and the interference signal code received power ISCP of NodeB.

Environmental correction factor determination module 302 comprises memory module and searches module.

Memory module is used to store the corresponding relation between wireless environment parameter, cover type and the environmental correction factor value.

Search module, be used for confirming the cover type of this NodeB self, find out the corresponding environmental correction factor value of wireless environment parameter that this NodeB receives the corresponding relation under the type between wireless environment parameter and the environmental correction factor value.

Adjusting module 303 is used for adopting the predetermined step-length CQI deviation CQI last to this UE that revise according to the block error rate BLER of this UE _OffsetAdjust, utilize said environmental correction factor pair adjustment result further to adjust again and obtain the current CQI of this UE _Offset, utilize the current CQI of this UE _OffsetCQI to this UE feedback adjusts.

Fig. 4 is that the Adjustment System of channel quality indicator (CQI) provided by the invention is formed sketch map.

As shown in Figure 4, this system comprises NodeB401 and UE402.

UE402 is used for reporting to NodeB401 the CQI of this UE402.

NodeB401 is used for confirming according to the wireless environment parameter environmental correction factor of CQI, adjusts according to the CQI of said environmental correction factor pair UE402 feedback.

Wireless environment parameter wherein comprises bandwidth total received power RTWP and the interference signal code received power ISCP of NodeB.

The above is merely preferred embodiment of the present invention, and is in order to restriction the present invention, not all within spirit of the present invention and principle, any modification of being made, is equal to replacement, improvement etc., all should be included within the scope that the present invention protects.

Claims (10)

1. the method for adjustment of a channel quality indicator (CQI) is characterized in that, this method comprises:

Base station NodeB is confirmed the wireless environment parameter;

NodeB confirms the environmental correction factor according to said wireless environment parameter;

NodeB adjusts according to the CQI that said environmental correction factor pair UE reports.

2. method according to claim 1 is characterized in that,

Said wireless environment parameter comprises: the bandwidth total received power RTWP of NodeB and interference signal code received power ISCP.

3. method according to claim 1 is characterized in that,

Store the corresponding relation between wireless environment parameter, cover type and the environmental correction factor value in advance in the NodeB side;

Said definite environmental correction factor comprises: NodeB confirms the cover type of self, finds out corresponding environmental correction factor value the corresponding relation under the type between wireless environment parameter and the environmental correction factor value.

4. method according to claim 1 is characterized in that, the CQI that said UE is reported adjusts and comprises:

Block error rate BLER according to this UE adopts the predetermined step-length CQI deviation CQI last to this UE that revise _OffsetAdjust, utilize said environmental correction factor pair adjustment result further to adjust again and obtain the current CQI of this UE _Offset, utilize the current CQI of this UE _OffsetThe CQI that this UE is reported adjusts.

5. the adjusting device of a channel quality indicator (CQI) is arranged in NodeB, it is characterized in that, this device comprises environmental parameter determination module, environmental correction factor determination module and adjusting module;

Said environmental parameter determination module is used for confirming the wireless environment parameter;

Said environmental correction factor determination module is used for confirming the environmental correction factor according to said wireless environment parameter;

Said adjusting module is used for adjusting according to the CQI that said environmental correction factor pair UE reports.

6. device according to claim 5 is characterized in that,

Said environmental parameter determination module is used for confirming bandwidth total received power RTWP and the interference signal code received power ISCP of NodeB.

7. device according to claim 5 is characterized in that, said environmental correction factor determination module comprises memory module and searches module;

Said memory module is used to store the corresponding relation between wireless environment parameter, cover type and the environmental correction factor value;

The said module of searching is used for confirming the cover type of this NodeB self finding out corresponding environmental correction factor value the corresponding relation under the type between wireless environment parameter and the environmental correction factor value.

8. device according to claim 5 is characterized in that,

Said adjusting module is used for adopting the predetermined step-length CQI deviation CQI last to this UE that revise according to the block error rate BLER of this UE _OffsetAdjust, utilize said environmental correction factor pair adjustment result further to adjust again and obtain the current CQI of this UE _Offset, utilize the current CQI of this UE _OffsetCQI to this UE feedback adjusts.

9. the Adjustment System of a channel quality indicator (CQI) is characterized in that, this system comprises NodeB and UE;

Said UE is used for reporting CQI to said NodeB;

Said NodeB is used for confirming according to the wireless environment parameter environmental correction factor of CQI, and the CQI that reports according to the said UE of said environmental correction factor pair adjusts.

10. system according to claim 9 is characterized in that, said wireless environment parameter comprises bandwidth total received power RTWP and the interference signal code received power ISCP of NodeB.

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