CN102026355B - E-HICH (enhanced hybrid automatic repeat request indicator channel) downlink power control method - Google Patents

Abstract

The invention discloses an E-HICH (enhanced hybrid automatic repeat request indicator channel) downlink power control method, comprising the following steps: UE (user equipment) calculates signal to noise ratio (SNR) of the current E-HICH subframe, the SNR is compared with the target SNR to determine a TPC (transmit power control) command, and the command is fed back to a Node B; after the Node B receives the fed-back TPC command, the Node B judges whether the information channel estimated performance is affected after the E-HICH power is adjusted according to the fed-back TPC command; if not, the E-HICH power is adjusted according to the TPC command; and if yes, the E-HICH power is further adjusted on the basis of the TPC command, so as to ensure the adjusted E-HICH power not to affect the information channel estimated performance. By adopting the invention, the E-HICH downlink power control can be realized, and the influence of E-HICH power change on the information channel estimated performance can be effectively avoided.

Description

The method for controlling downlink power of a kind of E-HICH

Technical field

The present invention relates to high speed uplink packet access (HSUPA) technology, the particularly method for controlling downlink power of a kind of E-HICH.

Background technology

At present, in the configuration of HSUPA, each carrier wave need to be supported the E-HICH of a scheduling type and the E-HICH of a non-scheduled type usually.No matter be the E-HICH of scheduling type or the E-HICH of non-scheduled type carries a plurality of UE usually in same subframe signal, but, on two types E-HICH, all do not use at present downlink power control (DLPC) and control the transmitted power of each UE signal of E-HICH carrying, but the transmitted power of the signal halves E-HICH of each UE.

Summary of the invention

In view of this, the invention provides the method for controlling downlink power of a kind of E-HICH, can rationally control the transmitted power of each UE signal that carries on the E-HICH.

For achieving the above object, the present invention adopts following technical scheme:

The method for controlling downlink power of a kind of E-HICH comprises:

UE calculates the signal to noise ratio snr of current E-HICH subframe, and compares with target SNR, if the SNR of described current E-HICH subframe is less than or equal to described target SNR, then is used to indicate the transmitting power control TPC instruction that improves transmitting power to the NodeB feedback; Otherwise, be used to indicate the TPC instruction that reduces transmitting power to the NodeB feedback.

Preferably, for non-scheduled E-HICH, the QPSK modulation is carried out in the TPC instruction that UE will need to feed back, and the TPC symbol after will modulating is multiplexed on the TPC territory on the non-scheduled E-PUCH;

In the TPC territory of the default scheduling E-HICH of scheduling E-PUCH, for scheduling E-HICH, the QPSK modulation is carried out in the TPC instruction that UE will need to feed back, and the TPC symbol after will modulating is multiplexed on the TPC territory of described scheduling E-HICH of scheduling E-PUCH.

Preferably, the mode of calculating the SNR of current E-HICH subframe is:

According to the demodulation result to current E-HICH subframe, calculate soft-decision bit sequence and correlation through the signature sequence of ovennodulation after the demodulation $C=\frac{\underset{n=1}{\overset{80}{\mathrm{\Σ}}}\hat{c}\left(n\right)C\left(n\right)}{80},$ And the power P of definite correlation C _s=| C| ², wherein, C (n) is the signature sequence of the described UE of process BPSK modulation,

It is 80 soft-decision bit sequence for length;

Compute sign level noise power P _n

Utilize the power P of described correlation C _sWith symbol level noise power P _nCalculating SNR is $\mathrm{SNR}=\frac{P_s}{P_n}.$

Preferably, the SNR that calculates is carried out recurrence average, carry out again the described operation that compares with target SNR.

The method for controlling downlink power of a kind of E-HICH, during the downlink power control of arbitrary E-HICH, the method comprises on carrying out current E-HICH subframe:

Receive the TPC instruction of all each self feed backs of UE of the above arbitrary E-HICH carrying of described current E-HICH subframe;

Judge that each UE deducts expectation transmitting power P at the midamble territory actual emission power of the corresponding E-HICH of a upper E-HICH subframe among described all UE _MidamblePoor, whether all be less than or equal to default threshold value, if, then with described expectation transmitting power P _MidambleAs at the midamble territory of described current the above arbitrary E-HICH of E-HICH subframe actual emission power P _Midamble', and adjust the transmitting power of corresponding UE according to described TPC instruction; Described expectation transmitting power P _MidambleFor, according to the described TPC instruction of feedback, adjust after the transmitting power of described each UE in the miadamble territory of current the above arbitrary E-HICH of E-HICH subframe transmitting power; Described default threshold value is: guaranteeing does not affect under the channel estimating performance prerequisite of described each UE, and the transmitting power in midamlbe territory allows the maximum power value of reduction;

Otherwise, determine the actual emission power of described each UE and the midamble territory actual emission power P of current the above arbitrary E-HICH of E-HICH subframe according to described default threshold value _Midamble', make described each UE deduct definite described midamble territory actual emission power P at the midamble territory actual emission power of the corresponding E-HICH of a upper E-HICH subframe _Midamble' poor, all be less than or equal to default threshold value.

Preferably, before described decision operation, the method further comprises: at the transmitting power P of current the above arbitrary E-HICH of E-HICH subframe (k), and all transmitting power sums that will calculate are as described expectation transmitting power according to described each UE of described TPC command calculations of feedback;

Determine the midamble territory actual emission power P of the described arbitrary E-HICH of current E-HICH subframe according to described default threshold value _Midamble' be: P _Midamble+ DELTA_MAX-TH, wherein, DELTA_MAX deducts maximum in the difference of described expectation transmitting power, the threshold value of TH for presetting for each UE at the midamble territory actual emission power of the corresponding E-HICH of a upper E-HICH subframe;

The actual emission power P (k) ' that determines described each UE is: P (k)+(DELTA_MAX-TH)/USERNum, and wherein, USERNum is the number of all UE of the above arbitrary E-HICH carrying of current E-HICH subframe, k is the index of UE.

Preferably, if described P _Midamble' greater than the maximum power P of described E-HICH, then the midamble territory actual emission power with the described arbitrary E-HICH of current E-HICH subframe is updated to P, and each UE is updated to P (k)-(P at the actual emission power of the described arbitrary E-HICH of current E-HICH subframe _Midamble'-P)/UserNum.

Preferably, when the UE that carries as the UE of the described E-HICH of described upper E-HICH subframe carrying and the described E-HICH of described current E-HICH subframe is identical, before described decision operation, the method further comprises: the UE number K1 and the UE number K2 that requires to reduce transmitting power that determine to require to improve transmitting power according to the described TPC instruction of feedback;

Described decision operation is: calculate (K2-K1) * step, when result of calculation was less than or equal to TH, the result who determines described judgement was yes, and when result of calculation during greater than TH, the result who determines described judgement is no; Described step is the step-length that power is adjusted.

Preferably, be to be used to indicate K2 the UE that reduces transmitting power from the TPC instruction of feeding back, select (K1+TH) individual UE, the TPC instruction that selected UE is fed back remains unchanged, and abandons the TPC instruction that non-selected UE feeds back among the described K2 UE; TPC instruction to feedback is to be used to indicate K1 the UE that improves transmitting power, keeps the TPC instruction of described K1 UE feedback constant;

According to the TPC instruction of determining, determine described each UE at the actual emission power of current the above E-HICH of E-HICH subframe, and all the transmitting power sums that will determine are as the midamble territory actual emission power of current the above E-HICH of E-HICH subframe.

As seen from the above technical solution, among the present invention, in the UE side, UE calculates the signal to noise ratio snr of current E-HICH subframe, and compare with target SNR, if the SNR of described current E-HICH subframe is less than or equal to described target SNR, then be used to indicate TPC (transmitting power control) instruction that improves transmitting power to the NodeB feedback; Otherwise, be used to indicate the TPC instruction that reduces transmitting power to the NodeB feedback.In the NodeB side, receive the TPC instruction of UE feedback, and TPC instruction corresponding to the UE that carries according to current E-HICH subframe, judge whether each UE is less than or equal to default threshold value in the difference of the actual emission power in the miadamble territory of a upper E-HICH subframe and the actual emission power in the midamble territory of the current E-HICH subframe of estimating according to the TPC instruction, if, after then showing the E-HICH transmitting power according to the TPC instruction adjustment UE that feeds back, can the channel estimating performance of UE not impacted, therefore can adjust the transmitting power of each UE on E-HICH according to the TPC instruction of feedback; If not, then show according to the TPC instruction of feedback and adjust each UE after the transmitting power on the E-HICH, can the channel estimating performance of upper each UE of E-HICH be impacted, therefore, determine the actual emission power of each UE and the actual emission power in midamble territory according to default threshold value, make each UE be less than or equal to default threshold value in the difference that the midamble territory of upper E-HICH subframe actual emission power deducts the midamble territory actual emission power of definite current subframe, can not affect the channel estimating performance of UE with the variation of the actual emission power that guarantees the midamble territory.By the way, namely can realize the downlink power control of E-HICH, and effectively avoid the power of E-HICH to change the impact that channel estimating performance is caused.

Embodiment

For making purpose of the present invention, technological means and advantage clearer, below in conjunction with accompanying drawing the present invention is described in further details.

E-HICH is a special down channel, and the transmitting power in the MIDAMBLE territory of this channel equals the transmitting power sum of the signal of upper all UE that carry of E-HICH.Because the power in MIDAMBLE territory has directly determined the performance of channel estimating, the raising of MIDAMBLE power and the demodulation performance that reduces the signal that will affect upper all UE of E-HICH.Usually, channel estimating performance variation within the specific limits allows, and can guarantee the demodulation performance of UE by rational demodulating algorithm.But when channel estimating performance deteriorates into to a certain degree, will cause the demodulation performance degradation of UE, so that can't reach the error rate of expection.Therefore, when carrying out the downlink power control of E-HICH in the present invention, demodulation performance for the signal of each UE of guaranteeing to carry on it, need the variation of control midamble territory power, guarantee that channel estimating performance can not exceed predetermined scope, for simplicity, will guarantee that below channel estimating performance can not exceed predetermined scope and not be called and can affect channel estimating performance.

As previously mentioned, the midamble territory transmitting power of E-HICH is the transmitting power sum of the signal of upper all UE that carry of E-HICH.Therefore, when the upper MIDAMBLE territory of E-HICH power descended, the channel estimating performance of upper all UE of E-HICH all can be affected.But, when MIDMABLE territory power has descended XdB, for the signal of the upper arbitrary UE that carries of E-HICH, usually can not cause the demodulation performance decline XdB of this UE signal, and only make the demodulation performance decline Y＜XdB of UE signal.Therefore, when the power in control midamble territory changes, need one by one judging of UE, take each UE at the midamble territory of upper E-HICH subframe power as benchmark, the midamble territory power of current E-HICH subframe is compared with it, change determining whether to affect channel estimating performance according to the midamble territory power of this UE.

Based on above-mentioned consideration, when carrying out the downlink power control of E-HICH among the present invention, processing in the UE side comprises: with reference to the downlink power control mode of other channels, generate TPC instruction " UP " or " DOWN " by UE according to the relation of the signal to noise ratio of UE signal on the current E-HICH subframe that receives and target signal to noise ratio, and with the TPC instruction feedback that generates to NODEB.

Particularly, the step of UE generation TPC instruction is as follows:

(1) UE estimates the received power of UE signal according to the coherent detection result.Estimation procedure is as follows:

If be used for the signature sequence of the ACK/NACK information of feedback " n " individual UE be: b (n).When NODEB need to feed back to UE with ACK information, NODEB sent to UE with the antitone sequence of signature sequence b (n); When NODEB need to feed back to UE with nack message, NODEB sent to UE with the former sequence of signature sequence b (n).

The sequence that NODEB determines to feed back to UE according to the method described above is c (n).When the ACK/NACK information of NODEB feedback was ACK information, c (n) was the antitone sequence of b (n); When the ACK/NACK information of NODEB feedback was ACK information, c (n) was b (n).

The sequence c (n) that feeds back to " n " individual UE is carried out the QPSK modulation, obtain symbol sebolic addressing x (n).NODEB is by the weighting sum of E-HICH with the symbol sebolic addressing of all UE $y\left(n\right)=\underset{i=1}{\overset{N}{\mathrm{\Σ}}}A\left(n\right)x\left(n\right),n=\mathrm{1,2},......,44$ Send to UE, here, the amplitude of the symbol sebolic addressing x (n) of n UE of A (n) expression, N has represented to carry on the E-HICH signal of N UE.

UE carries out the estimation that joint-detection obtains the symbol sebolic addressing of the upper carrying of E-HICH by the reception signal to the E-HICH subframe

It is the estimated value of y (n).

UE pair

Carry out the QPSK demodulation and disturb, obtain the soft-decision bit sequence.And from the soft-decision bit sequence, remove 8 idle bits (that is: the 41st bit-the 48th bit), obtain length and be 80 soft-decision bit sequence

UE carries out the BPSK modulation to b (n), obtains symbol sebolic addressing C (n). $C\left(n\right)=\left\{\begin{array}{c}1,b\left(n\right)=1\\ -1,b\left(n\right)=0\end{array}\right.$

Calculate the soft-decision bit sequence

And the correlation of C (n) $C=\frac{\underset{n=1}{\overset{80}{\mathrm{\Σ}}}\hat{c}\left(n\right)C\left(n\right)}{80}.$

Ask the power of correlation as the received power of UE signal: P _s=| C| ², i.e. P _sEqual C mould square;

(2) according to received power and the noise power calculation SNR of UE signal: $\mathrm{SNR}=\frac{P_s}{P_n},$ Wherein, P _nBe the symbol level noise power, the computational methods of this power see also existing document; Further, can also carry out recurrence to SNR result of calculation average.

(3) according to the average SNR of recurrence and the comparative result of SNR desired value, generate the TPC instruction.If less than or equal to the SNR desired value, then generating, the average SNR of recurrence is used to indicate the TPC instruction that improves transmitting power, i.e. " UP " order; If greater than the SNR desired value, then generating, the average SNR of recurrence is used to indicate the TPC instruction that reduces transmitting power, i.e. " DOWN " order; And with the TPC instruction feedback that generates to NodeB.

For non-scheduled E-HICH, this TPC instruction is carried to NodeB by the TPC territory on the non-scheduled E-PUCH.The number in the upper TPC territory of non-scheduled E-PUCH equals the number of the upper E-UCCH of non-scheduled E-PUCH.The QPSK modulation is carried out in the TPC order that generates according to the method described above, obtained the TPC symbol.This TPC symbol is multiplexed on the TPC territory of non-scheduled E-PUCH.

For scheduling E-HICH, the TPC territory of a scheduling E-HICH is set in scheduling E-PUCH.On the scheduling E-PUCH on the number in the TPC territory of scheduling E-HICH and the scheduling E-PUCH number of E-UCCH identical.The QPSK modulation is carried out in the TPC order that generates according to the method described above, obtained the TPC symbol.This TPC symbol is multiplexed on the TPC territory of scheduling E-HICH of scheduling E-PUCH.

Processing at network side comprises: after NodeB receives the TPC instruction of each UE feedback, after E-HICH power is adjusted in the TPC instruction of the feedback of each UE of basis for estimation, whether can exert an influence to channel estimating performance, if can not exert an influence, then adjust E-HICH power according to the TPC instruction, if can exert an influence, then need on TPC instruction basis, do further adjustment to E-HICH power, can not exert an influence to channel estimating performance to guarantee the E-HICH power after the adjustment.

Above-mentioned downlink power control mode is all carried out for a certain E-HICH, the mode of E-HICH all in the system being carried out downlink power control is all identical, and, for the transmission of each E-HICH, its downlink power control mode is also identical, and the subframe that each E-HICH is transmitted is called the E-HICH subframe.Above processing procedure to the UE side is described, and the below is described in detail the processing procedure of NodeB side, and only take to the downlink power control process of a specific E-HICH channel-E-HICH1 as example, specific implementation is described.If carry out the transmission that the E-HICH of downlink power control is transmitted as current E-HICH subframe (being made as subframe N), the power of this time transmission is to carry out according to the TPC instruction of each UE feedback, and the TPC instruction of UE feedback is the (M＜N) according to the reception signal generation of M E-HICH.Here, N=M+d _Ul+ d _Dl, d _DlExpression UE passes through " M+d according to the DLPC order of the E-HICH of the reception signal generation of the E-HICH of " M " subframe _Dl" E-PUCH of subframe carries to NODEB.d _UlExpression UE is by " M+d _Dl" E-PUCH of subframe carry TPC order to the E-HICH of UE extracted by NODEB after for " N=M+d _Ul+ d _Dl" downlink power control of subframe E-HICH.

Particularly, NodeB comprises in the concrete processing procedure of the downlink power control that carries out the upper E-HICH1 of current E-HICH subframe (being subframe N):

Receive subframe " M+d _Dl" the upward TPC instruction of all each self feed backs of UE of E-HICH1 carrying.

Judge that each UE deducts the poor of expectation transmitting power at the midamble territory of E-HICH corresponding to subframe M actual emission power among above-mentioned all UE, whether all be less than or equal to default threshold value, if, then determine can not impact channel estimation results, to estimate the midamble territory actual emission power of transmitting power as E-HICH1 on subframe N, and adjust the transmitting power of corresponding UE according to the TPC instruction that receives; Otherwise, determine the actual emission power of each UE and the midamble territory actual emission power of the upper E-HICH of subframe N according to default threshold value, make each UE all be less than or equal to default threshold value in the difference that the midamble territory actual emission power of the corresponding E-HICH of subframe M deducts definite midamble territory actual emission power.

Wherein, estimate after transmitting power is for the transmitting power of adjusting each UE according to the TPC instruction of feedback the miadamble territory transmitting power of E-HICH1 on subframe N; Default threshold value is: guaranteeing does not affect under the channel estimating performance prerequisite of each UE, the transmitting power in midamlbe territory allows the maximum power value of reduction, the relevant power change values of aforesaid midamble territory preset range namely, this threshold value can be determined by emulation according to the indexs such as target error rate of system.

In the above-mentioned processing procedure, the UE that E-HICH1 carries on subframe N, on subframe M, not necessarily also be carried on the E-HICH1, therefore, when judging whether to affect channel estimating performance, the expectation transmitting power in the midamble territory of the upper E-HICH1 of subframe N that need to obtain according to the TPC command calculations of reception compares with the midamble territory transmitting power of this UE corresponding E-HICH (not necessarily E-HICH1) on subframe M.

In the situation that the most general, the UE no matter upper E-HICH1 of subframe N carries, on subframe M, whether still be carried on the E-HICH1, the processing of above-mentioned network side all can be adopted following pervasive implementation, suppose that NODEB is when sending the E-HICH signal of N subframe, the signal of K UE of the upper carrying of this E-HICH, then the processing of network side specifically comprises:

Step 101 receives the TPC instruction of K each self feed back of UE of the upper E-HICH1 carrying of subframe N;

Step 102 is according to the transmitting power P (N, k) of each UE of the TPC command calculations E-HICH1 on subframe N that feeds back;

Particularly, go up arbitrary UE that E-HICH1 carries for subframe N, TPC instruction according to its feedback, this UE on subframe M is adjusted in the transmitting power of its place E-HICH, obtain the transmitting power of this UE E-HICH1 on subframe N, and each UE that the upper E-HICH1 of subframe N carries is all adopted in the same way according to TPC instruction determine transmitting power.For example, for k UE, the TPC instruction of feedback is " UP ", if the E-HICH transmitting power of upper this UE of subframe M is P (M, k), then the transmitting power P (N of the E-HICH1 of this UE on subframe N, k) be P (M, k)+and STEP, wherein, STEP is the power increment that the TPC instruction causes.

Step 103 is with the transmitting power sum of each UE in the step 102 expectation transmitting power P as the midamble territory of E-HICH1 on subframe N _Midamble

As previously mentioned, on E-HICH, the transmitting power in midamble territory is the transmitting power sum of all UE of the upper carrying of this E-HICH, therefore, after this step is carried out the transmitting power adjustment for calculating according to the TPC instruction, the expectation transmitting power in midamble territory, i.e. P _Midamble=SUM (P (N, k)).

Step 104, the expectation transmitting power that step 103 is obtained compares with each UE midamble territory transmitting power of corresponding E-HICH on subframe M, judges whether to impact channel estimation results, if, then execution in step 105, otherwise, execution in step 106.

If each UE among K UE, when the M subframe sent, the power in M subframe midamble territory was MIDPOWER (M, k), then SUM (P (N, k)) and the MIDPOWER (M, k) of each UE was compared.

If the MIDPOWER (M of any one UE, k)-SUM (P (N, k))＜=TH, then not thinking can affect channel estimating performance, namely because N subframe MIDAMBLE territory power is SUM (P (N, k)) channel estimating performance of each UE that causes changes (with respect to MIDPOWER (M, k)) can ignore, execution in step 105 is directly determined subframe N upward transmitting power and the midamble territory transmitting power of each UE that E-HICH1 carries according to the TPC instruction.

If have the MIDPOWER (M of a UE at least, k)-SUM (P (N, k))=DELTA (k)＞TH, then thinking to affect channel estimating performance, namely because N subframe MIDAMBLE territory power is SUM (P (N, k)), the channel estimating performance of the UE that causes descends larger, then execution in step 106, and the transmitting power of determining according to the TPC instruction is further adjusted.

Wherein, TH is default threshold value, can set according to the excursion that channel estimating performance allows.

Step 105, with the transmitting power of each UE E-HICH1 on subframe N of calculating in the step 102 as actual emission power, the expectation transmitting power P that step 103 is calculated _MidambleMidamble territory actual emission power P as the upper E-HICH1 of subframe N _Midamble'.

Step 106 is determined the upward midamble territory actual emission power P of E-HICH1 of subframe N according to default threshold value TH _Midamble' and the transmitting power of each UE.

According to the judgement in the abovementioned steps 104 as seen, the expectation transmitting power in the midamble territory that calculates in the step 103 is lower, causes affecting the channel estimating performance of part UE, therefore, needs to improve the transmitting power in midamble territory.In this step, determine that the actual emission power Pmidamble ' in midamble territory is SUM (P (N, k))+(DELTA_MAX-TH), wherein, DELTA_MAX is the maximum among the difference DELTA (k) that calculates in the step 104.And the transmitting power of each UE is adjusted into: P (N, k)+(DELTA_MAX-TH)/USERNum (N), wherein, and the UE sum that USERNum (N) expression N subframe E-HICH1 carries, k is the index of UE.

So far, namely finished the downlink power control of E-HICH1 on subframe N.

On the basis of above-mentioned processing, be no more than the maximum transmission power P of E-HICH for the actual emission power that guarantees the midamble territory, can further include following processing:

Step 107, the actual emission power P when the midamble territory _Midamble' during greater than the maximum power P of E-HICH, the midamble territory actual emission power of the upper E-HICH1 of subframe N is updated to P, the actual emission power of each UE E-HICH1 on subframe N is updated to P (N, k) '-(P _Midamble'-P)/UserNum (N), wherein, P (N, k) ' is the actual emission power of the E-HICH1 of step 105 or 106 determined k UE.

Above-mentioned for the most generally speaking, the embodiment of the downlink power control of E-HICH.When the E-HICH1 of subframe M and subframe N upward carries K identical UE, a kind of processing mode of simplification can also be arranged:

NODEB to subframe N on K UE carrying of E-HICH1 when determining transmitted power,

NodeB at first receives the TPC instruction of K UE feedback, and the UE that establishes feedback " UP " among K the UE has K1, and the UE of feedback " DOWN " has K2 and K2+K1=K;

TPC instruction according to feedback, calculate the midamble territory transmitting power of the upper E-HICH1 of subframe N with respect to the reduction value of the midamble territory transmitting power of the upper E-HICH1 of subframe M: (K2-K1) * STEP, if expression NODEB responds the DLPC order of all K UE simultaneously, at MIDAMBLE territory power decline (K2-K1) * STEP the dB of the MIDAMBLE territory of N subframe E-HICH power with respect to M subframe E-HICH;

If the reduction value (K2-K1) that calculates * STEP＜=TH, represent that then NODEB responds under the DLPC command situation of all K UE simultaneously, descend and to accept at the MIDAMBLE territory power of the MIDAMBLE territory of N subframe E-HICH power with respect to M subframe E-HICH, can not cause on the demodulation performance of each UE large impact; Then can adjust the transmitting power of each UE according to the TPC instruction, namely with step 105;

If the reduction value (K2-K1) that calculates * STEP＞TH, represent that then NODEB responds under the DLPC command situation of all K UE simultaneously, power cannot be accepted with respect to the decline of the MIDAMBLE territory power of M subframe E-HICH in the MIDAMBLE territory of N subframe E-HICH.In this case, need to further adjust the transmitting power of each definite UE of foundation TPC instruction.

Concrete adjustment mode can be carried out according to the mode of above-mentioned steps 106, perhaps can also more simply process: be merely able to respond " UP " order of K1 UE at N subframe NODEB, " DOWN " order of response (K1+TH) individual UE, specifically can from K2 UE, choose " K1+TH " individual UE wantonly, the TPC instruction of the UE that selects is remained unchanged, respond " DOWN " order of these selected UE; " DOWN " order of non-selected UE among K2 the UE is dropped; The TPC instruction that to feed back K1 the UE of " UP " order remains unchanged; According to the above-mentioned TPC instruction that redefines the E-HICH power of each UE is adjusted, and the power after will adjusting and as the actual emission power in the midamble territory of the upper E-HICH1 of subframe N.

After determining actual emission power, be no more than the maximum transmission power P of E-HICH for the actual emission power that guarantees the midamble territory, can also adopt mode as hereinbefore, the actual emission power of determining is done further renewal.

The above-mentioned concrete mode that is the E-HICH downlink power control among the present invention.By said process as seen, the present invention not only can realize the E-HICH downlink power control, can guarantee that the transmitting power of determining can not affect channel estimating performance simultaneously.

Being preferred embodiment of the present invention only below, is not for limiting protection scope of the present invention.Within the spirit and principles in the present invention all, any modification of doing, be equal to replacement, improvement etc., all should be included within protection scope of the present invention.

Claims (5)

1. the method for controlling downlink power of an E-HICH is characterized in that, during the downlink power control of arbitrary E-HICH, the method comprises on carrying out current E-HICH subframe:

Receive the TPC instruction of all each self feed backs of UE of the above arbitrary E-HICH carrying of described current E-HICH subframe;

Judge that each UE deducts expectation transmitting power P at the midamble territory actual emission power of the corresponding E-HICH of a upper E-HICH subframe among described all UE _MidamblePoor, whether all be less than or equal to default threshold value, if, then with described expectation transmitting power P _MidambleAs at the midamble territory of described current the above arbitrary E-HICH of E-HICH subframe actual emission power P _Midamble', and adjust the transmitting power of corresponding UE according to described TPC instruction; Described expectation transmitting power P _MidambleFor, according to the described TPC instruction of feedback, adjust after the transmitting power of described each UE in the midamble territory of current the above arbitrary E-HICH of E-HICH subframe transmitting power; Described default threshold value is: guaranteeing does not affect under the channel estimating performance prerequisite of described each UE, and the transmitting power in midamble territory allows the maximum power value of reduction;

Otherwise, determine the actual emission power of described each UE and the midamble territory actual emission power P of current the above arbitrary E-HICH of E-HICH subframe according to described default threshold value _Midamble', make described each UE deduct definite described midamble territory actual emission power P at the midamble territory actual emission power of the corresponding E-HICH of a upper E-HICH subframe _Midamble' poor, all be less than or equal to default threshold value.

2. method according to claim 1, it is characterized in that, before described decision operation, the method further comprises: at the transmitting power P of current the above arbitrary E-HICH of E-HICH subframe (k), and all transmitting power sums that will calculate are as described expectation transmitting power according to described each UE of described TPC command calculations of feedback;

Determine the midamble territory actual emission power P of the described arbitrary E-HICH of current E-HICH subframe according to described default threshold value _Midamble' be: P _Midamble+ DELTA_MAX-TH, wherein, DELTA_MAX deducts maximum in the difference of described expectation transmitting power, the threshold value of TH for presetting for each UE at the midamble territory actual emission power of the corresponding E-HICH of a upper E-HICH subframe;

The actual emission power P (k) ' that determines described each UE is: P (k)+(DELTA_MAX-TH)/USERNum, and wherein, USERNum is the number of all UE of the above arbitrary E-HICH carrying of current E-HICH subframe, k is the index of UE.

3. method according to claim 2 is characterized in that, if described P _Midamble' greater than the maximum power P of described E-HICH, then the midamble territory actual emission power with the described arbitrary E-HICH of current E-HICH subframe is updated to P, and each UE is updated to P (k)-(P at the actual emission power of the described arbitrary E-HICH of current E-HICH subframe _Midamble'-P)/UserNum.

4. method according to claim 1, it is characterized in that, when the UE that carries as the UE of the described E-HICH of described upper E-HICH subframe carrying and the described E-HICH of described current E-HICH subframe is identical, before described decision operation, the method further comprises: the UE number K1 and the UE number K2 that requires to reduce transmitting power that determine to require to improve transmitting power according to the described TPC instruction of feedback;

Described decision operation is: calculate (K2-K1) * step, when result of calculation was less than or equal to default threshold value TH, the result who determines described judgement was yes, and when result of calculation during greater than TH, the result who determines described judgement is no; Described step is the step-length that power is adjusted.

5. method according to claim 4, it is characterized in that, be to be used to indicate K2 the UE that reduces transmitting power from the TPC instruction of feedback, select (K1+TH) individual UE, the TPC instruction of selected UE feedback is remained unchanged, abandon the TPC instruction that non-selected UE feeds back among the described K2 UE; TPC instruction to feedback is to be used to indicate K1 the UE that improves transmitting power, keeps the TPC instruction of described K1 UE feedback constant;

According to the TPC instruction of determining, determine described each UE at the actual emission power of current the above E-HICH of E-HICH subframe, and all the transmitting power sums that will determine are as the midamble territory actual emission power of current the above E-HICH of E-HICH subframe.