CN1805325A - Method for improving channel quality indication accuracy - Google Patents

Abstract

The invention relates to a method for improving channel quality instruction accuracy, which uses channel information attained by processing the HS-SCCHi+1 between the HS-DSCHi and the HS-SICHi, and the ascending adjoint DPCH to correct the CQI, to improve the decrease of throughput of system caused by the non-real time property, without additional complexity.

Description

Improve the method for channel quality indication accuracy

Technical field

The present invention relates to a kind of method of improving channel quality indication accuracy.Relate in particular in the 1.28 megahertz time division duplex high speed descending grouping access systems, in the frequency division duplex system of three generations's partnership relation and 3.84 megahertz time division duplex high speed downlink packet welding systems in a kind of method of improving channel quality indication accuracy.

Background technology

From the R5 version of 3GPP (three generations's partnership relation) technical standard, HSDPA (high speed downlink packet access) as a kind of enhancement techniques of 3G mobile communication system formally by standardization.(1.28Mcps megahertz) TDD (time division duplex) HSDPA mainly adopted defeated, the short TTI of AMC (Adaptive Modulation and Coding), FCS (fast cell selection), multi-antenna transmitting (Transmission Time Interval) (5ms) and HARQ (mixing automatic repeat requests) wait some novel technology to improve the throughput (Throughput) of system.

AMC belongs to a kind of link adaptation techniques, its basic principle is exactly the transmission rate according to the channel situation self-adapted adjustment system, when signal to noise ratio when higher, adopt higher order of modulation and code rate, otherwise promptly adopt lower order of modulation and code rate.

The realization of AMC will face several challenges.The combination of at first, too much modulation, encoding scheme (MCS) can increase the complexity of system.In 3GPP technical standard 25.321, stipulated clearly that 1.28Mcps HSDPA only adopts QPSK (four phase shift keyings) and two kinds of modulation systems of 16QAM (quadrature amplitude modulation), and the access capability of UE (terminal) is divided into three classes, the transmission block size of each class in a TTI is defined as 64 kinds of selections, and this has reduced the complexity of system design effectively.Secondly, AMC is very responsive to the sum of errors time-delay of channel measurement.In order to select suitable modulation and code rate, the scheduling on upper strata must have accurately quality of channel to be understood.Otherwise might be because of having adopted too high modulation, code rate and cause frame error rate too high, or have adopted lower modulation, code rate and caused the loss of power system capacity.

According to standard, the physical layer procedures of Node (node) B can be described as in the 1.28Mcps HSDPA system:

Whether step 1, NodeB emission HS-SCCH (the special-purpose shared control channel of HS-DSCH) will receive corresponding HS-DSCH (high speed descending sharing channel) with notice UE, be at least three time slots at interval between first time slot of HS-SCCH and HS-DSCH, and HS-DSCH to be in same subframe or adjacent sub-frame with the HS-SCCH of correspondence.

Step 2, NodeB adopt the indicated physical resource emission HS-DSCH of HS-SCCH.

Step 3, when the HS-SICH that receives UE emission (the special-purpose information channel of sharing of HS-DSCH), status report ACK/NACK (affirmation/non-affirmation) and CQI (channel quality indication) are reported to high level.

According to standard, the physical layer procedures of UE end can be described as in the 1.28Mcps HSDPA system:

Step 1, after high level provides indication, UE should monitor HS-SCCHs set, and decoding HS-SCCH goes up entrained information.

If the information of carrying on step 2 HS-SCCH has been passed through the verification of CRC (cyclic redundancy check (CRC)), and UE ID that HS-SCCH carries and the identity of UE are consistent, UE should handle and the corresponding HS-DSCHs of HS-SCCH (high-speed physical downlink shared channel (HS-PDSCH)), otherwise the data that just abandon HS-SCCH and comprised continue to detect the HS-SCCH of next subframe.

Step 3, handled after the HS-DSCHs, UE handles the status report (ACK/NACK) of correctness by the HS-SICH emission about HS-DSCH and reflects the information CQI of physics transmission channel quality.Wherein CQI comprise HS-DSCH transmission the modulation system and the TFRI (transformat and resource information) that should adopt.

A HSDPA cycle that three steps of UE end physical layer procedures is called UE.Fig. 1 has described a common UE end HSDPA cyclic flow schematic diagram.

In 1.28Mcps HSDPA system, definite principle of CQI should be to have maximum TB (transmission block) at the Block Error Rate (BLER) that guarantees HS-DSCH under less than 10% prerequisite, and standard has been stipulated HS-DSCH _iLast time slot and HS-SICH _iBetween the interval should be at least nine time slots, because the characteristics that become when the physical channel of mobile communication has, even the UE that is obtained by HS-DSCH is accurately to the measurement of channel, but because UE can produce the unmatched phenomenon of modulation, encoding scheme and channel that is adopted equally to the hysteresis quality that the NodeB report is produced.

Summary of the invention

A kind of method of improving channel quality indication accuracy provided by the invention is utilized and is handled HS-DSCH _iAnd HS-SICH _iBetween HS-SCCH _I+1With the channel information that the descending DPCH of following (DPCH) is obtained CQI is proofreaied and correct, thereby the throughput of system that non real-time brought that improves CQI to a certain extent descends, and do not need the extra too many complexity that increases.

In order to achieve the above object, the invention provides a kind of method of improving channel quality indication accuracy, the HSDPA cycle of a UE end comprises following steps:

Step 1, processing HS-SCCH _iTo obtain HS-SCCH _iEntrained information bit;

Step 2, according to handling HS-SCCH _iThe information bit that obtains can obtain HS-SCCH _iThe UE ID that carries, this UE ID conforms to as the ID with the UE end, then carry out step 3, as not conforming to, then makes i=i+1, returns and carry out step 1;

Step 3, processing HS-DSCH _i, and according to HS-DSCH _iBlock Error Rate obtain corresponding C QI;

If step 4 is proofreaied and correct CQI and is not hindered HS-SCCH _I+1Emission on time, then handle HS-SCCH _I+1With follow descending DPCH, obtain HS-SCCH _I+1The channel information of corresponding time slot, and according to n subframe HS-SCCH _iCompare to revise CQI with the channel information of following the corresponding time slot of descending DPCH, hinder HS-SCCH if proofread and correct CQI _I+1Emission on time, direct execution in step 5 then;

Step 5, CQI and ACK/NACK information are passed through HS-SICH _iFeed back to NodeB;

In the described step 4, utilize HS-SCCH _I+1With follow descending DPCH the channel information of corresponding time slot proofread and correct CQI, but specifically how to proofread and correct, then need according to by HS-DSCH _iThe specific algorithm of determining CQI comes specific implementation.

A kind of method of improving channel quality indication accuracy provided by the invention is utilized and is handled HS-DSCH _iAnd HS-SICH _iBetween HS-SCCH _I+1With the channel information that the descending DPCH of following is obtained CQI is proofreaied and correct, thereby the throughput of system that non real-time brought that improves CQI to a certain extent descends, and do not need the extra too many complexity that increases.

Description of drawings

Fig. 1 is common UE end HSDPA cyclic flow schematic diagram in the background technology;

Fig. 2 is the sequential organization figure that illustrates a HSDPA cycle, the HS-SCCH here _iOn TS2, follow descending DPCH on TS4;

Fig. 3 is the HSDPA cyclic flow schematic diagram of a UE end in a kind of method of improving channel quality indication accuracy provided by the invention;

Fig. 4 handles HS-SCCH _iTo obtain HS-SCCH _iThe schematic flow sheet of entrained information bit;

Fig. 5 handles HS-DSCH _iSchematic flow sheet.

Embodiment

Followingly specify preferred forms of the present invention according to Fig. 2 to Fig. 5:

As shown in Figure 3, the invention provides a kind of method of improving channel quality indication accuracy, i the HSDPA cycle of UE end comprises following steps:

Step 1, processing HS-SCCH _iTo obtain HS-SCCH _iEntrained information bit (as shown in Figure 4);

Step 2, according to handling HS-SCCH _iThe information bit that obtains can obtain HS-SCCH _iThe UE ID that carries, this UE ID conforms to as the ID with the UE end, then carry out step 3, as not conforming to, then makes i=i+1, returns and carry out step 1;

Step 3, processing HS-DSCH _i, and according to HS-DSCH _iBlock Error Rate obtain corresponding C QI (as shown in Figure 5);

If step 4 is proofreaied and correct CQI and is not hindered HS-SCCH _I+1Emission on time, then handle HS-SCCH _I+1With follow descending DPCH, obtain HS-SCCH _I+1The channel information of corresponding time slot, and according to n subframe HS-SCCH _iCompare to revise CQI with the channel information of following the corresponding time slot of descending DPCH, hinder HS-SCCH if proofread and correct CQI _I+1Emission on time, direct execution in step 5 then;

Step 5, CQI and ACK/NACK information are passed through HS-SICH _iFeed back to NodeB;

In the described step 4, utilize HS-SCCH _I+1With follow descending DPCH the channel information of corresponding time slot proofread and correct CQI, but specifically how to proofread and correct, then need according to by HS-DSCH _iThe specific algorithm of determining CQI comes specific implementation.

Specific embodiment: (as shown in Figures 2 and 3)

Step 1, processing HS-SCCH _iTo obtain HS-SCCH _iEntrained information bit;

Step 2, according to HS-SCCH _iThe UE ID that carries conforms to as the ID of this UE ID with the UE end, then carry out step 3, as not conforming to, then makes i=i+1, returns and carry out step 1;

Step 3, processing HS-DSCH _i, and definite CQI:

Step 3.1, establish HS-DSCH _iCorresponding emission symbolic representation is S (QPSK or a 16QAM symbol), can obtain the estimation of S by joint-detection at the UE end

$\tilde{S}=S+n$

N is an additive white Gaussian noise;

The energy of step 3.2, estimation n is made as σ ²

Step 3.3, establish emission symbol S _k(k=1,2 ..., L) (concerning QPSK, L=4, and concerning 16QAM, L=16) satisfy $\frac{1}{L}\underset{k=1}{\overset{L}{\mathrm{\Σ}}}{\left|S_k\right|}^2=1,$ Then can obtain i HSDPA cycle joint-detection HS-DSCH _iSignal interference ratio SIR afterwards _i=1/ σ ²

Step 3.4, in conjunction with SIR _iAnd HS-DSCH _iCode rate, modulation system, can table look-up by the form of prior formulation and obtain CQI;

Step 4, correction CQI:

Step 4.1, is as shown in Figure 2 established n subframe HS-SCCH _iCarry out with the TS2 that follows descending DPCH correspondence and TS4 that the final path responses of selecting is h after channel estimating and the Path selection _{N, 2} ¹, h _{N, 2} ²..., h _{N, 2} ^kAnd h _{N, 4} ¹, h _{N, 4} ²..., h _{N, 4} ^j, wherein the n in the subscript represents the n subframe, and 2 and 4 represent TS2 and TS4 respectively, and subscript k and j represent the number in selected path among TS2 and the TS4 respectively.

Step 4.2, correction SIR _l:

${\stackrel{\‾}{\mathrm{SIR}}}_{i,\mathrm{new}}={\stackrel{\‾}{\mathrm{SIR}}}_i*\frac{{\left|h_{n,2}^1\right|}^2+{\left|h_{n,2}^2\right|}^2+\·\·\·+{\left|h_{n,2}^k\right|}^2+{\left|h_{n,4}^1\right|}^2+{\left|h_{n,4}^2\right|}^2+\·\·\·+{\left|h_{n,4}^j\right|}^2}{{\left|h_{n+\mathrm{1,2}}^1\right|}^2+{\left|h_{n+\mathrm{1,2}}^2\right|}^2+\·\·\·+{\left|h_{n+\mathrm{1,2}}^k\right|}^2+{\left|h_{n+\mathrm{1,4}}^1\right|}^2+{\left|h_{n+\mathrm{1,4}}^2\right|}^2+\·\·\·+{\left|h_{n+\mathrm{1,4}}^j\right|}^2}$

Step 4.3, according to SIR _{L, new}Again table look-up and determine CQI, finish correction CQI;

Step 5, CQI and ACK/NACK information after will proofreading and correct are passed through HS-SICH _iFeed back to NodeB;

A kind of method of improving channel quality indication accuracy provided by the invention is utilized and is handled HS-DSCH _iAnd HS-SICH _iBetween HS-SCCH _I+1With the channel information that the descending DPCH of following is obtained CQI is proofreaied and correct, thereby the throughput of system that non real-time brought that improves CQI to a certain extent descends, and do not need the extra too many complexity that increases.

Claims (4)

1. a method of improving channel quality indication accuracy is characterized in that, comprises following steps:

Step 1, processing HS-SCCH _iTo obtain HS-SCCH _iEntrained information bit;

Step 2, according to handling HS-SCCH _iThe information bit that obtains can obtain HS-SCCH _iThe UE ID that carries, this UE ID conforms to as the ID with the UE end, then carry out step 3, as not conforming to, then makes i=i+1, returns and carry out step 1:

Step 3, processing HS-DSCH _i, and according to HS-DSCH _iBlock Error Rate obtain corresponding C QI;

If step 4 is proofreaied and correct CQI and is not hindered HS-SCCH _I+1Emission on time, then handle HS-SCCH _I+1With follow descending DPCH, obtain HS-SCCH _I+1The channel information of corresponding time slot, and according to n subframe HS-SCCH _iCompare to revise CQI with the channel information of following the corresponding time slot of descending DPCH, hinder HS-SCCH if proofread and correct CQI _I+1Emission on time, direct execution in step 5 then;

Step 5, CQI and ACK/NACK information are passed through HS-SICH _iFeed back to NodeB.

2. the method for improving channel quality indication accuracy as claimed in claim 1 is characterized in that, also comprises following steps in the step 3:

Step 3.1, establish HS-DSCH _iCorresponding emission symbolic representation is S, can obtain the estimation of S by joint-detection at the UE end

$\tilde{S}=S+n$

N is an additive white Gaussian noise;

The energy of step 3.2, estimation n is made as σ ²

Step 3.3, establish emission symbol S _k(k=1,2 ..., L) satisfy $\frac{1}{L}\underset{k=1}{\overset{L}{\mathrm{\Σ}}}{\left|S_k\right|}^2=1$ , then can obtain i HSDPA cycle joint-detection HS-DSCH _iSignal interference ratio SIR afterwards _i=1 σ ²

Step 3.4, in conjunction with SIR _i, and HS-DSCH _iCode rate, modulation system, can table look-up by the form of prior formulation and obtain CQI.

3. the method for improving channel quality indication accuracy as claimed in claim 1 is characterized in that, also comprises following steps in the step 4:

Step 4.1, establish n subframe HS-SCCH _iCarry out with the TS2 that follows descending DPCH correspondence and TS4 that the final path responses of selecting is h after channel estimating and the Path selection _{N, 2} ¹, h _{N, 2} ²..., h _{N, 2} ^kAnd h _{N, 4} ¹, h _{N, 4} ²..., n _{N, 4} ^j, wherein the n in the subscript represents the n subframe, and 2 and 4 represent TS2 and TS4 respectively, and subscript k and j represent the number in selected path among TS2 and the TS4 respectively;

Step 4.2, correction SIR _i:

${\stackrel{\‾}{\mathrm{SIR}}}_{i,\mathrm{new}}={\stackrel{\‾}{\mathrm{SIR}}}_i*\frac{{\left|h_{n,2}^1\right|}^2+{\left|h_{n,2}^2\right|}^2+\·\·\·+{\left|h_{n,2}^k\right|}^2+{\left|h_{n,4}^1\right|}^2+{\left|h_{n,4}^2\right|}^2+\·\·\·+{\left|h_{n,4}^j\right|}^2}{{{|h}_{n+\mathrm{1,2}}^1|}^2+{\left|h_{n+\mathrm{1,2}}^2\right|}^2+\·\·\·+{\left|h_{n+\mathrm{1,2}}^k\right|}^2+{\left|h_{n+\mathrm{1,4}}^2\right|}^2+{\left|h_{n+\mathrm{1,4}}^2\right|}^2+\·\·\·+{\left|h_{n+\mathrm{1,4}}^j\right|}^2}$

Step 4.3, according to SIR _{I, new}Again table look-up and determine CQI, finish correction CQI.

4. the method for improving channel quality indication accuracy as claimed in claim 2 is characterized in that, in the step 3.3, and emission symbol S _k(k=1,2 ..., the L) L in: concerning QPSK, L=4, and concerning 16QAM, L=16.

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