CN101052148A - High speed downward grouping cut-in method for base station and correcting method for channel quality instruction - Google Patents

Abstract

In invention can improve the error of selecting coding mode transmission format by base station caused by CQI non-realtime. It comprise: at number i+1 sub-frame, the base station detects and gets the channel quality indication (CQI) carried in HS-SICH and the parameter of upper channel for un-directly shoring the character of downlink channel carried by the number i-1 sub-frame; according to the channel parameter and the signal interference ratio corresponding to the number i-1 sub-frame CQI, the base station makes correction for the CQI to the get the corrected CQI.

Description

The bearing calibration of the high speed downward grouping cut-in method of base station and channel quality indication

Technical field

This method relates to a kind of wireless communication process method, is specifically related to a kind of method of channel quality indicator (CQI) (Channel Quality Indicator) and high speed downlink packet access handling process of base station of proofreading and correct in high speed descending grouping access system.

Background technology

In order to satisfy user's demand growing, introduced high speed downlink packet access (HSDPA, High Speed Downlink Packet Access) technology among the 3GPP R5 to high-speed packet data service.For TD-SCDMA (Time Division Synchronous Code Division Multiple Access, TD SDMA inserts), HSDPA mainly is by introducing HS-DSCH (HighSpeed Downlink Packet Access, high speed descending sharing channel) strengthens air interface, simultaneously, introduce HS-SCCH (High speed Shared Control Channel for HS-DSCH, High-Speed Shared Control Channel) and HS-SICH (High speed Shared Information Channel for HS-DSCH, high-speed shared information channel) finishes control corresponding, and increase the function corresponding entity at Node B (B node, promptly usually said base station) and finish.It seems from physical layer, mainly be to adopt AMC (Adaptive Modulation and Coding, Adaptive Modulation and Coding) technology, HARQ (HybridAutomatic Repeat Request, mix automatic repeat requests) technology and FCS (Fast CellSelection, fast cell is selected) technology increases the throughput of data.

3GPP TS 25.224 regulations for HS-DSCH, are selected modulation scheme and suitable transmission rate by the high level that is positioned at Node B.This will realize by transmission block size, modulation system and the Radio Resource that it is suitable that high level is selected HS-DSCH.The selection of parameter can be carried out based on the channel quality indicator (CQI) that UE (User Equipment, subscriber equipment) reports.The whole link adaptive process of HS-DSCH comprises Node B process and UE process, and this two processes are described respectively below:

Node B process:

(1) Node B sends HS-SCCH, and carrying UE identification number is used to refer to TTI (Transmission Time Interval, the Transmission Time Interval) position of the HS-DSCH of UE distribution above.If UE obtains continuous HS-DSCH transmitting and scheduling, will use identical HS-SCCH as control channel;

(2) Node B sends HS-DSCH, and its Radio Resource that uses is gone up the Radio Resource of indication as HS-SCCH;

(3) Node B receives the HS-SICH of object UE, and the status report (ACK/NACK and CQI) that HS-SICH is carried sends high level to.

The UE process:

(1) UE obtains high-rise the indication when needing monitoring HS-SCCH, begins to monitor all concentrated HS-SCCH channels of HS-SCCH of high-rise configuration;

(2) in a single day receive the correct HS-SCCH of CRC, UE will read the information of the HS-PDSCH corresponding with this HS-SCCH.Corresponding relation between the HS-PDSCH that HS-SCCH controlled is provided by high level.If receive the HS-SCCH of crc error, UE will be discarded in HS-SCCH and go up the data that receive, and continue monitoring HS-SCCH collection;

(3) receive HS-PDSCH, UE will produce ACK/NACK information and send to Node B together with the CQI information that the nearest time obtains on corresponding HS-SICH.

Channel quality indication (CQI) provides by transmitting the estimated value of the code rate that can maximize the single transmission throughput that the HS-DSCH decoding obtains last time for Node B.3GPP TS 25.224 regulations report process as follows:

(1) UE obtains the resource allocation conditions of next HS-DSCH by down control channel (HS-SCCH) message that receives this user;

(2) UE receives this user's HS-DSCH, and by the CQI that measures of necessity, the purpose that CQI estimates is exactly to obtain maximum single transmission throughput under BLER is not more than 10% prerequisite;

(3) CQI of corresponding HS-DSCH report, UE should be sending on an available HS-SICH that HS-DSCH transmits subsequently, unless HS-SICH is being close to last transmission time slot of HS-DSCH, in this case, UE will use next available HS-SICH to transmit.

3GPP TS 25.221 has provided the timing relationship between each correlated channels of HSDPA:

(1) correspondence effectively HS-PDSCH distribution next time, the corresponding gap information of HS-DSCH carries on HS-SCCH, this information provides according to a restriction: to an appointment UE, between the HS-DSCH (on the time) of the HS-SCCH that carries the HS-DSCH corresponding information and first indication a n is arranged _HS-SCCHThe skew of 〉=3 time slots.

(2) UE effectively follows on the HS-SICH at the next one and sends the corresponding ACK/NACK of HS-DSCH and need following qualification: specify UE to one, a n is in the end arranged between HS-PDSCH of a distribution (on the time) and the HS-SICH _HS-SICHThe skew of 〉=9 time slots.

Fig. 1 has provided a kind of three continuous HSDPA subframe timing relationship schematic diagrames.

According to top description, in order to obtain CQI value correctly, a kind of method is SIR (the Signal Interference Ratio that UE estimates the HS-PDSCH channel earlier, signal interference ratio, can obtain by signal calculated average and variance), then according to the HS-PDSCH signal interference ratio, from SIR-CQI value mapping table, choose corresponding C QI value, SIR-CQI value mapping table is to formulate in advance, can obtain the information content of the HS-SCCH that the CQI decision that obtains according to tabling look-up issues and the modulation that HS-DSCH uses and the Radio Resource of coded system and use according to emulation or measured result.

For convenience of description, complete HSDPA course of work of definition is:

(1) Node B sends HS-SCCH;

(2) Node B sends HS-DSCH, uses HS-SCCH to go up the Radio Resource of indication;

(3) UE receives HS-SCCH;

(4) UE will read the information of the HS-PDSCH corresponding with this HS-SCCH;

(5) receive HS-PDSCH, UE will produce and send to Node B on the HS-SICH;

(6) Node B receives the HS-SICH of UE, and the status report (ACK/NACK and CQI) that HS-SICH is carried sends high level to.

Fig. 2 is the HSDPA handling process (base station portion of only drawing) of base station, comprising:

Step 201, base station detect the HS-SICH of i-1 the HSDPA course of work i+1 subframe _I-1To obtain HS-SICH _I-1Entrained information bit comprises CQI _I-1Information;

Step 202 is according to CQI _I-1Determine i+1 HSDPA course of work HS-SCCH _I+1The information content that issues;

Step 203 is with the transformat and the Radio Resource transmission HS-DSCH of corresponding modulation coding mode, use _I+1

Step 204, base station begin to receive the HS-SICH of i the HSDPA course of work i+2 subframe _i, system enters i+2 the HSDPA course of work.

The AMC of HSDPA is very responsive to the sum of errors time delay of channel measurement.In order to select suitable modulation and coded system, scheduler program must be known channel quality condition.This just means that when channel estimating is inaccurate scheduler program can be selected wrong modulation coding mode, and the system that makes can not be adaptive to the variation of channel, not only can not play optimization function, can make performance poorer on the contrary.

Know that by 3GPP TS 25.224 definite principle of CQI should be less than having maximum TB (Transport Block, transmission block) under 10% the prerequisite at the BLER (Block Error Ratio, Block Error Rate) that guarantees HS-DSCH.Description and Fig. 1, Fig. 2 by the front know HS-DSCH _iLast time slot and HS-SICH _iBetween the interval should be at least 9 time slots, that is to say because UE has the time-delay of 9 time slots at least to the process of Node B reporting channel quality, because mobile channel has time-varying characteristics, even UE is accurately by the CQI that HS-DSCH obtains, because the delay of time, the variation of channel quality can not in time pass to the base station, modulation, coded system that the base station is determined according to this CQI may be not corresponding with current channel quality, cause the HSDPA mis-behave, influence communication quality of communication systems.

Summary of the invention

The technical problem to be solved in the present invention provides the method for proofreading and correct the channel quality indication in a kind of high speed descending grouping access system, can improve the error that the base station of being caused by the CQI non real-time is selected coded system, transformat and Radio Resource, improve systematic function.

The TD-SCDMA system is owing to the use of uplink and downlink channel is identical frequency, adopt the mode of time division duplex to come work, the wireless environment consistency of up link and down link is fine, the uplink and downlink channel relevancy is stronger, therefore, the base station can utilize the conforming characteristics of TD-SCDMA system uplink and downlink channel, with the descending HS-DSCH channel quality indicator (CQI) of up HS-SICH channel estimating information correction.The base station receives and writes down the channel information of up HS-SICH channel, channel information according to last time in current channel information that receives and the record, the CQI that correction receives from UE, the content and the modulation coding mode of corresponding HS-DSCH employing, the transformat and the Radio Resource of use that issues according to the definite HS-SCCH next time of the CQI that proofreaies and correct then.By proofreading and correct, to improve the systematic function decline that the CQI non real-time causes.

The method of correction channel quality indication is characterized in that when the present invention proposed a kind of TD-SCDMA system high speed downlink grouped and inserts, and may further comprise the steps:

(a) channel quality indicator (CQI) that carries among the high-speed shared information channel HS-SICH of i-1 subframe and the up channel parameter that reflects the down channel characteristic are indirectly detected and obtained in the base station i+1 subframe;

(b) proofread and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe described base station, the CQI after obtaining to proofread and correct.

Further, the up channel parameter of described indirect reflection down channel characteristic is the channel impulse response coefficient.

Further, in described step (b), described base station is proofreaied and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe and is meant that described base station is according to the channel quality indicator (CQI) of described i-1 subframe _I-1Obtain corresponding signal interference ratio SIR _I-1, again according to the channel parameter of i-2 subframe of the channel parameter of i-1 subframe and preservation to SIR _I-1Proofread and correct, according to the SIR after proofreading and correct _{I-1, new}Obtain CQI _{I-1, new}, this CQI _{I-1, new}Be the CQI after the correction.

Further, described step (b) further may further comprise the steps:

(b1) described base station is according to described CQI _I-1Look into the CQI-SIR table and obtain SIR _I-1

(b2) described base station one or more channel impulse response coefficients of stating the up channel correspondence according to i-2 subframe place of one or more channel impulse response coefficients of the up channel correspondence at i-1 subframe place and preservation obtain correction coefficient k, adopt described correction coefficient to SIR _I-1Proofread and correct the SIR after obtaining proofreading and correct _{I-1, new}, SIR _{I-1, new}=kSIR _I-1

(b3) described base station is according to the SIR after proofreading and correct _{I-1, new}Look into the CQI-SIR table again and determine CQI _{I-1, new}, finish CQI _I-1Correction.

Further, described correction coefficient k is the ratio of quadratic sum of one or more impulse response coefficient modules at the quadratic sum of one or more impulse response coefficient modules at described i-1 subframe place and described i-2 subframe place.

In order to address the above problem, the present invention also provides the high speed downlink packet access processing method of base station in a kind of TD SDMA access, it is characterized in that, may further comprise the steps:

(A) channel quality indicator (CQI) that carries among the high-speed shared information channel HS-SICH of i-1 subframe and the up channel parameter that reflects the down channel characteristic are indirectly detected and obtained in the base station i+1 subframe;

(B) proofread and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe described base station, the CQI after obtaining to proofread and correct;

(C) content of the High-Speed Shared Control Channel that issues is determined in described base station according to the CQI after proofreading and correct, and adopts respective coding mode, transformat and Radio Resource to send high speed descending sharing channel.

Further, the up channel parameter of described indirect reflection down channel characteristic is the channel impulse response coefficient.

Further, in described step (B), described base station is proofreaied and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe and is meant that described base station is according to the channel quality indicator (CQI) of described i-1 subframe _I-1Obtain corresponding signal interference ratio SIR _I-1, again according to the channel parameter of i-2 subframe of the channel parameter of i-1 subframe and preservation to SIR _I-1Proofread and correct, according to the SIR after proofreading and correct _{I-1, new}Obtain CQI _{I-1, new}, this CQI _{I-1, new}Be the CQI after the correction.

Further, described step (B) further may further comprise the steps:

(B1) described base station is according to described CQI _I-1Look into the CQI-SIR table and obtain SIR _I-1

(B2) described base station one or more channel impulse response coefficients of stating the up channel correspondence according to i-2 subframe place of one or more channel impulse response coefficients of the up channel correspondence at i-1 subframe place and preservation obtain correction coefficient k, adopt described correction coefficient to SIR _I-1Proofread and correct the SIR after obtaining proofreading and correct _{I-1, new}, SIR _{I-1, new}=kSIR _I-1

(B3) described base station is according to the SIR after proofreading and correct _{I-1, new}Look into the CQI-SIR table again and determine CQI _{I-1, new}, finish CQI _I-1Correction.

Further, described correction coefficient k is the ratio of quadratic sum of one or more impulse response coefficient modules at the quadratic sum of one or more impulse response coefficient modules at described i-1 subframe place and described i-2 subframe place.

The bearing calibration of adopting the present invention to propose, channel quality indication to the reflection down channel quality on the base station is proofreaied and correct, realization is to the assessment of down channel quality, improve accuracy of indicating channel quality, can effectively follow the tracks of the situation of change of channel, make coded system, transformat and the Radio Resource that adopt the base station and current channel condition meets most, make system self-adaption, improve the system communication performance in channel variation.

Description of drawings

Fig. 1 is a kind of three continuous HSDPA subframe timing relationship schematic diagrames;

Fig. 2 is the HSDPA process chart of base station in the prior art;

Fig. 3 is the HSDPA process chart that contains the base station of proofreading and correct the CQI step in the present embodiment;

Fig. 4 is the process chart that CQI is proofreaied and correct in the base station in the present embodiment.

Embodiment

Below in conjunction with the drawings and specific embodiments the present invention is described in further detail.

As shown in Figure 3, i+1 HSDPA handling process of present embodiment base station may further comprise the steps:

Step 301, base station are obtained the HS-SICH of i-1 subframe i+1 subframe by joint-detection _I-1Entrained information bit comprises CQI _I-1Information, the channel impulse response coefficient h _I-1 ¹, h _I-1 ²..., h _I-1 ⁿ, wherein n represents the multipath number chosen;

I subframe, also can obtain the HS-SICH of i-2 subframe by the joint-detection of base station end _I-2Corresponding channel impulse response coefficient h _I-2 ¹, h _I-2 ²..., h _I-2 ^m, wherein m represents the multipath number chosen, proofreaies and correct for i+1 subframe CQI and uses.

The channel impulse response coefficient is the up channel parameter that reflects the down channel characteristic indirectly.

Step 302 is proofreaied and correct CQI _I-1Obtain CQI _{I-1, new}

Step 303, the base station is according to the CQI that proofreaies and correct _{I-1, new}Determine i+1 HSDPA cycle H S-SCCH _I+1The content that issues;

Step 304 adopts the transformat of corresponding modulation coding mode, use and Radio Resource to send HS-DSCH _I+1

Step 305 detects HS-SICH _iEnter HSDPA handling process next time.

In i+1 the subframe handling process in base station, proofread and correct CQI _{I, new}Specific implementation as shown in Figure 4, may further comprise the steps:

Step 401, the CQI that obtains according to decoding _I-1Information is looked into the CQI-SIR table and is obtained SIR _I-1

CQI-SIR value mapping table is to formulate in advance, can obtain according to emulation or measured result.

Step 402 is proofreaied and correct SIR _I-1, obtain SIR _{I-1, new}, concrete grammar is as follows:

${\mathrm{SIR}}_{i-1,\mathrm{new}}={\mathrm{SIR}}_{i-1}*\frac{\underset{l=1}{\overset{n}{\mathrm{\Σ}}}{\left|h_{i-1}^l\right|}^2}{\underset{k=1}{\overset{m}{\mathrm{\Σ}}}{\left|h_{i-2}^k\right|}^2}$

Wherein, h _I-2 ¹, h _I-2 ²..., h _I-2 ^mAnd h _I-1 ¹, h _I-1 ²..., h _I-1 ⁿAll obtain in i subframe and i+1 subframe joint-detection by the base station, $\frac{\underset{l=1}{\overset{n}{\mathrm{\Σ}}}{\left|h_{i-1}^l\right|}^2}{\underset{k=1}{\overset{m}{\mathrm{\Σ}}}{\left|h_{i-2}^k\right|}^2}$ Being correction coefficient, is the ratio of quadratic sum of one or more impulse response coefficient modules at the quadratic sum of one or more impulse response coefficient modules at i-1 subframe place and i-2 subframe place.

Step 403 is according to the SIR after proofreading and correct _{I-1, new}Again look into SIR-CQI table (being aforementioned CQI-SIR table) and determine CQI _{I-1, new}, finish CQI _{I, new}Proofread and correct;

The above is the preferred embodiments of the present invention only, is not limited to the present invention, and for a person skilled in the art, the present invention can have various changes and variation.Within the spirit and principles in the present invention all, any modification of being done, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (10)

1. The method of correction channel quality indication is characterized in that when 1, a kind of TD-SCDMA system high speed downlink grouped inserted, and may further comprise the steps:

   (a) channel quality indicator (CQI) that carries among the high-speed shared information channel HS-SICH of i-1 subframe and the up channel parameter that reflects the down channel characteristic are indirectly detected and obtained in the base station i+1 subframe;

   (b) proofread and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe described base station, the CQI after obtaining to proofread and correct.
2. 2, the method for claim 1 is characterized in that, the up channel parameter of described indirect reflection down channel characteristic is the channel impulse response coefficient.
3. 3, method as claimed in claim 2, it is characterized in that, in described step (b), described base station is proofreaied and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe and is meant that described base station is according to the channel quality indicator (CQI) of described i-1 subframe _I-1Obtain corresponding signal interference ratio SIR _I-1, again according to the channel parameter of i-2 subframe of the channel parameter of i-1 subframe and preservation to SIR _I-1Proofread and correct, according to the SIR after proofreading and correct _{I-1, new}Obtain CQI _{I-1, new}, this CQI _{I-1, new}Be the CQI after the correction.
4. 4, method as claimed in claim 3 is characterized in that, described step (b) further may further comprise the steps:

   (b1) described base station is according to described CQI _I-1Look into the CQI-SIR table and obtain SIR _I-1

   (b2) described base station one or more channel impulse response coefficients of stating the up channel correspondence according to i-2 subframe place of one or more channel impulse response coefficients of the up channel correspondence at i-1 subframe place and preservation obtain correction coefficient k, adopt described correction coefficient to SIR _I-1Proofread and correct the SIR after obtaining proofreading and correct _{I-1, new}, SIR _{I-1, new}=kSIR _I-1

   (b3) described base station is according to the SIR after proofreading and correct _{I-1, new}Look into the CQI-SIR table again and determine CQI _{I-1, new}, finish CQI _I-1Correction.
5. 5, method as claimed in claim 4, it is characterized in that described correction coefficient k is the ratio of quadratic sum of one or more impulse response coefficient modules at the quadratic sum of one or more impulse response coefficient modules at described i-1 subframe place and described i-2 subframe place.
6. 6, the high speed downlink packet access processing method of base station is characterized in that during a kind of TD SDMA inserted, and may further comprise the steps:

   (A) channel quality indicator (CQI) that carries among the high-speed shared information channel HS-SICH of i-1 subframe and the up channel parameter that reflects the down channel characteristic are indirectly detected and obtained in the base station i+1 subframe;

   (B) proofread and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe described base station, the CQI after obtaining to proofread and correct;

   (C) content of the High-Speed Shared Control Channel that issues is determined in described base station according to the CQI after proofreading and correct, and adopts respective coding mode, transformat and Radio Resource to send high speed descending sharing channel.
7. 7, method as claimed in claim 6 is characterized in that, the up channel parameter of described indirect reflection down channel characteristic is the channel impulse response coefficient.
8. 8, method as claimed in claim 7, it is characterized in that, in described step (B), described base station is proofreaied and correct described CQI according to the pairing signal interference ratio SIR of the CQI of described channel parameter and described i-1 subframe and is meant that described base station is according to the channel quality indicator (CQI) of described i-1 subframe _I-1Obtain corresponding signal interference ratio SIR _I-1, again according to the channel parameter of i-2 subframe of the channel parameter of i-1 subframe and preservation to SIR _I-1Proofread and correct, according to the SIR after proofreading and correct _{I-1, new}Obtain CQI _{I-1, new}, this CQI _{I-1, new}Be the CQI after the correction.
9. 9, method as claimed in claim 8 is characterized in that, described step (B) further may further comprise the steps:

   (B1) described base station is according to described CQI _I-1Look into the CQI-SIR table and obtain SIR _I-1

   (B2) described base station one or more channel impulse response coefficients of stating the up channel correspondence according to i-2 subframe place of one or more channel impulse response coefficients of the up channel correspondence at i-1 subframe place and preservation obtain correction coefficient k, adopt described correction coefficient to SIR _I-1Proofread and correct the SIR after obtaining proofreading and correct _{I-1, new}, SIR _{I-1, new}=kSIR _I-1

   (B3) described base station is according to the SIR after proofreading and correct _{I-1, new}Look into the CQI-SIR table again and determine CQI _{I-1, new}, finish CQI _I-1Correction.
10. 10, method as claimed in claim 9, it is characterized in that described correction coefficient k is the ratio of quadratic sum of one or more impulse response coefficient modules at the quadratic sum of one or more impulse response coefficient modules at described i-1 subframe place and described i-2 subframe place.

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