CN100426688C - Purblind channel estimating method for broadband CDMA system - Google Patents
Purblind channel estimating method for broadband CDMA system Download PDFInfo
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Abstract
The present invention provides a semiblind channel estimation method for a wideband code division multiple access system, and relates to a precise channel estimation method in a wideband code division multiple access system WCDMA in a wireless mobile communication field. The present invention does not hard decide a maximum rate merge result of non-pilot signals, but adopts different decoding modes according to different encoding modes of non-pilot symbols TFCI and TPC. The present invention provides a Rake receiver in a mobile communication system, which comprises a channel estimation module, wherein the channel estimation module is used for computing the channel estimation value of each path; the channel estimation module is composed of a pilot frequency, a TFCI and a TPC signal separation modules which are used for separating various signals in a time slot. Because the present invention adopts the different decoding modes according to the different encoding modes of the non-pilot symbols TFCI and the TPC, the present invention can lower the code error rate of the non-pilot symbols TFCI and the TPC, enhance the accuracy of the channel estimation and improve the system performance.
Description
Technical field
The present invention relates in the wireless mobile communications field method of channel estimating in the Direct-Spread code division multiple access system, more specifically is how to carry out channel estimating accurately in broadband CDMA system (WCDMA).
Background technology
In 3-G (Generation Three mobile communication system), wireless channel is enough wide, utilizes spread spectrum and code division multiple access, and a plurality of users can use identical channel.Utilize direct spreading sequence, information symbol is represented by the sequence of chip.Therefore because mobile communication is to carry out under the electric wave environment of complexity, how overcoming the multipath fading phenomenon that radio wave propagation causes is a basic problem of mobile communication.In the Direct-Spread code division multiple access system, owing to use wide-band spread spectrum, the correlation bandwidth of radiofrequency signal bandwidth ratio decline is much bigger, thereby can adopt Rake receiver from received signal, to tell the component in different paths, separate respectively to be in harmonious proportion and merge, thereby can strengthen received signal, improve signal to noise ratio.Channel estimating is a very important processing in this process, because it can directly influence the performance of Rake receiver.
In the WCDMA system, use frequency pilot sign ancillary technique (Pilot Symbol AidedMethod) at present, promptly the periodic frequency pilot sign that inserts carries out channel estimating in data bit flow, its essence is exactly the estimation that obtains channel fading process sampled point by known frequency pilot sign, obtains the channel parameter corresponding of data symbol again by the correlated channels algorithm for estimating.Fig. 1 and Fig. 2 represent the frame structure of the descending and special uplink channel of WCDMA respectively, and the one frame length all is 10ms, and 15 time slots are formed a frame.For the time slot of up link, DPCCH (Dedicated Physical Control Channel, Dedicated Physical Control Channel) and DPDCH (Dedicated Physical Data Channel, Dedicated Physical Data Channel) are parallel the transmissions.DPCCH is again by N
PilotIndividual frequency pilot sign, N
TFCIIndividual TFCI (Transport Format CombinationIndicator, transformat combination indication) symbol, N
TPCIndividual TPC (Transmit Power Control, transmitting power control) symbol and N
FBIIndividual FBI (Feedback Information, feedback information) symbol is formed.
In the receiver of WCDMA communication system, pilot signal and data-signal are two available informations in the channel estimating, thereby form two kinds of channel estimating modes: based on the channel estimating of pilot signal, and the channel estimating of joint pilot signal and data-signal.
For channel estimating based on pilot signal, up to the present a lot of methods has been proposed, picture MMSE (least mean-square error) algorithm, LMS (lowest mean square) algorithm, RLS (recurrence least square) algorithm, Wiener filter method, Kalman filter method, first-order linear filter method, first order nonlinear filter method, Gauss interpolation method and WMSA (Weighted Multi-slot Averaging, weighting multi-slot filter method).Under the lower situation of travelling carriage translational speed, channel fading changes slow, can comparatively accurately must describe the characteristic of channel according to the channel parameter that above method obtains, and makes the channel compensation result of DPCCH satisfy system requirements.But when wireless channel changes than very fast or noise ratio greatly, only rely on pilot signal to carry out channel estimating and just seem not much of that.
For the channel estimating of joint pilot signal and data-signal, belong to half-blindness and estimate, be one of main direction of research at present.Owing to when using pilot signal, utilize data-signal to carry out channel estimating, therefore can obtain more channel information, improve the accuracy of channel estimating.But just there is a Hen important problem here, how obtains the value of data-signal.Because the non-frequency pilot sign of DPCCH is ignorant in advance, use them to carry out channel estimating and will know their value earlier.Proposed a kind of method of semi-blind channel estimation among the U.S. Pat 6700919B1 " CHANNELESTIMATION FOR COMMUNICATION SYSTEM USING WEIGHTEDESTIMATES BASED ON PILOT DATA AND INFORMATION DATA ", Fig. 5 represents U.S. Pat 6700919B1 channel estimation module block diagram.In circulation channel estimation module 54, carry out initial channel estimation with the pilot signal in the time slot, channel estimation value is sent into Rake merge and in the module 56 each directly to be carried out high specific and merge, amalgamation result is sent to carries out the value that hard decision obtains each non-frequency pilot sign in the hard decision module 59.
But we must consider the error rate size of the non-frequency pilot sign value that obtains like this, because when the value of certain non-frequency pilot sign is mistake, the channel estimation value that obtains in conjunction with mismark not only can not improve, also can be poorer than not in conjunction with this symbol the time.Therefore the key point that to reduce the non-frequency pilot sign error rate be exactly semi-blind channel estimation, the present invention is conceived to how to improve the decoding correctness of non-pilot signal just.
Summary of the invention
The objective of the invention is will be in utilizing Dedicated Control Channel the pilot signal and the semi-blind channel estimation of non-pilot signal in, by reducing the error rate of non-pilot signal, improve the performance of semi-blind channel estimation greatly, thereby can improve the performance of whole system.
The present invention can not directly use hard decision to the high specific amalgamation result of non-pilot signal, but at non-frequency pilot sign TFCI, the difference of TPC coded system adopts different decoding processes, and details are as follows for concrete steps:
(1) the Dedicated Physical Control Channel component in each footpath is sent into pilot tone, TFCI and TPC signal separation module, with the various Signal Separation in the time slot;
(2) the pilot tone envelope is sent to the first initial channel estimation module and obtains first channel estimation value;
(3) conjugation and the TFCI signal with first channel estimation value is sent in first multiplier, and conjugate multiplication obtains the channel compensation component of TFCI;
(4) TFCI symbol judgement module is delivered in the channel compensation component addition of the TFCI in each footpath, and TFCI is carried out symbol judgement;
(5) TFCI signal and the TFCI symbol that obtains of judgement are all delivered in second multiplier, obtain the TFCI envelope, pilot tone envelope and TFCI envelope are all delivered to the second initial channel estimation module obtain second channel estimation value;
(6) conjugation and the TPC signal with second channel estimation value is sent in the 3rd multiplier, and conjugate multiplication obtains the channel compensation component of TPC, and TPC symbol judgement module is delivered in the channel compensation component addition of the TPC in each footpath, and TPC is carried out symbol judgement;
(7) the TPC signal is all delivered in the 4th multiplier with the TPC symbol that judgement obtains, and obtains the TPC envelope;
(8) with the pilot tone envelope, TPC envelope and TFCI envelope are all delivered to channel estimation module, obtain the channel estimation value in each footpath.
The present invention also is to provide the Rake receiver in a kind of mobile communication system, comprises channel estimation module (402), is used to calculate the channel estimation value in each footpath, and this channel estimation module is by forming with the lower part:
Pilot tone, TFCI and TPC signal separation module are used for the various Signal Separation with time slot;
The first initial channel estimation module utilizes the pilot tone envelope of input to obtain first channel estimation value;
First multiplier is used for the conjugation of first channel estimation value and the channel compensation component that the TFCI signal multiplication obtains TFCI;
First adder carries out addition to the channel compensation component of TFCI in each footpath;
TFCI symbol judgement module, utilize addition the channel compensation component of TFCI in each footpath TFCI is carried out symbol judgement;
Second multiplier is used for TFCI signal and the TFCI that obtains of judgement and multiplies each other and obtain the TFCI envelope;
The second initial channel estimation module utilizes pilot tone envelope and TFCI envelope to adopt average method to obtain second channel estimation value;
The 3rd multiplier, the channel compensation component that the conjugation and the TPC signal multiplication of second channel estimation value obtained TPC;
Second adder is with the channel compensation component addition of each TPC directly;
TPC symbol judgement module, utilize addition the channel compensation component of TPC TPC is carried out symbol judgement;
The 4th multiplier, the TPC symbol that utilizes TPC signal and judgement to obtain obtains the TPC envelope;
Channel estimation module utilizes the pilot tone envelope, and TPC envelope and TFCI envelope adopt moving average, and the adaptive filtering method is carried out the channel estimation value that channel estimating obtains each footpath automatically.
Because at frequency pilot sign TFCI, the difference of TPC coded system adopts different decoding processes among the present invention.Compare with direct hard decision, can reduce the error rate of non-frequency pilot sign TFCI and TPC greatly.So just can improve the accuracy of channel estimating, improve systematic function.
Description of drawings
In conjunction with the drawings can reasonable description this programme, thus characteristics of the present invention are showed better.
Fig. 1 represents the frame assumption diagram of downlink dedicated channel
Fig. 2 represents the frame assumption diagram of up-link
Fig. 3 represents to pass the chnnel coding figure of TFCI information bit
Fig. 4 represents the structure chart of Rake receiver.
Fig. 5 represents U.S. Pat 6700919 B1 channel estimation module block diagrams.
Fig. 6 represents the channel estimation module block diagram.
Fig. 7 represents TFCI symbol judgement module map.
Fig. 8 represents TPC symbol judgement module
Embodiment
Be described in further detail below in conjunction with the enforcement of accompanying drawing to technical scheme, according to these structure charts, the technical staff in same field can be easy to realize the present invention.
At first the TFCI signal is decoded.Carry out initial channel estimation with each footpath frequency pilot sign in time slot, carry out conjugate multiplication with the non-frequency pilot sign TFCI in its initial estimate and this footpath, the channel compensation component with each TFCI directly carries out the high specific merging then.Collect the TFCI value of 15 time slots in the frame, can obtain length is the 30TFCI sequence, and adding 2 zero to the end, to obtain length be 32 TFCI sequence.Decode according to the TFCI sequence that quick Ha Mada transfer pair obtains, obtain length and be 10 TFCI information sequence.Sub-code (subcode) (32, the 10) coding that 10 long TFCI information sequences is carried out again second order Reed-Muller sign indicating number (Reed-Mo Le sign indicating number) has obtained 32 long TFCI codings.The TFCI that newly obtains preceding 30 symbols of encoding are divided into 15 groups and deliver to respectively in the time slot corresponding, so just obtained the TFCI value of symbol of each time slot.
Carry out the decoding of TPC signal then.Carry out initial channel estimation in conjunction with frequency pilot sign and two TFCI symbols in each footpath time slot, carry out conjugate multiplication with the initial estimate that obtains and the non-frequency pilot sign TPC in this footpath, the channel compensation component with each TPC directly carries out the high specific merging then.In most of the cases, NTPC equals 2, promptly has two TPC signals in a time slot.Stipulate that from the 3G agreement two TPC symbols are identical as can be known, 11 expression power control commands, 1,00 expression power control command 0.Therefore the result after we can merge high specific carries out earlier on average, and then carries out hard decision, and the TPC error rate that obtains so also can descend greatly.
At last the FBI signal is decoded.If there is a FBI symbol, in conjunction with the pilot signal in each footpath time slot, TFCI and TPC signal carry out initial channel estimation, carry out conjugate multiplication with the initial estimate that obtains and the non-frequency pilot sign FBI in this footpath, and the FBI component with each footpath carries out the high specific merging then.Be combined the result and carry out the value that hard decision obtains the FBI symbol.
Through above processing, just can obtain the non-frequency pilot sign value in the whole time slot.By in conjunction with frequency pilot sign and non-frequency pilot sign, obtain the channel estimation value of a complete time slot.
Non-pilot signal in DPCCH comprises TFCI, FBI and TPC, and be the example explanation with the most frequent No. 0 time slot format that uses of DPCCH here.In this form, N
PilotEqual 6, N
TFCIEqual 2, and N
FBIEqual zero, promptly in time slot, do not have FBI.We know from the 3GPP agreement, and 10 TFCI information bit a are arranged in the frame
0..., a
9(a
0Be LSB (Least Significant Bits, least significant bit), a
9Be MSB (Most Significant Bit, highest significant position), utilize 10 code words of second order Reed-Muller to carry out linear block encoding [32,10] and obtained 32 long coding b
0, b
1..., b
31, the coding flow process as shown in Figure 3.Can be expressed as,
Wherein each provisional capital of generator matrix G is the code word of a second order Reed-Muller, and the basic sequence of TFCI sign indicating number (32,10) is as shown in the table.The minimum range of this linear block codes is 12, but owing to used preceding 30 in 32 symbols in the reality, its minimum range is 10 as can be known as calculated.According to the knowledge of coding theory, when using Hard decision decoding, this coding can be corrected 4 hard decision mistakes.And, under the high s/n ratio situation, can correct 9 hard decision mistakes because what adopt is Soft decision decoding in this programme.
Under normal circumstances, 32 long TFCI coding b
0, b
1..., b
31In preceding 30 b
0, b
1..., b
29Being divided into 15 components is fitted in 15 time slots in the frame.High specific merges 30 TFCI signals afterwards in the frame by collecting at receiving terminal
Add two zero in the burst back and gather enough 32, adopt fast hadamard transform (fast hadamard transform) to decode, obtain the information bit a of TFCI it
0..., a
9Then again to information bit a
0..., a
9Sub-code (32, the 10) coding that carries out second order Reed-Muller sign indicating number obtains coded sequence b
1, b
2..., b
31, wherein preceding 30 decoded results that symbol is exactly the TFCI signal.Because there is very big coding gain in TFCI, obtain the error rate of TFCI symbol than directly carrying out behind the coding again by decoding
i | g i,0 | g i,1 | g i,2 | g i,3 | g i,4 | g i,5 | g i,6 | g i,7 | g i,8 | g i,9 |
0 | 1 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
1 | 0 | 1 | 0 | 0 | 0 | 1 | 1 | 0 | 0 | 0 |
2 | 1 | 1 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 1 |
3 | 0 | 0 | 1 | 0 | 0 | 1 | 1 | 0 | 1 | 1 |
4 | 1 | 0 | 1 | 0 | 0 | 1 | 0 | 0 | 0 | 1 |
5 | 0 | 1 | 1 | 0 | 0 | 1 | 0 | 0 | 1 | 0 |
6 | 1 | 1 | 1 | 0 | 0 | 1 | 0 | 1 | 0 | 0 |
7 | 0 | 0 | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 0 |
8 | 1 | 0 | 0 | 1 | 0 | 1 | 1 | 1 | 1 | 0 |
9 | 0 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 |
10 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | 0 | 1 | 1 |
11 | 0 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 1 | 0 |
12 | 1 | 0 | 1 | 1 | 0 | 1 | 0 | 1 | 0 | 1 |
13 | 0 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 1 |
14 | 1 | 1 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 1 |
15 | 1 | 0 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 0 |
16 | 0 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 1 |
17 | 1 | 1 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 0 |
18 | 0 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 |
19 | 1 | 0 | 1 | 0 | 1 | 1 | 0 | 1 | 0 | 1 |
20 | 0 | 1 | 1 | 0 | 1 | 1 | 0 | 0 | 1 | 1 |
21 | 1 | 1 | 1 | 0 | 1 | 1 | 0 | 1 | 1 | 1 |
22 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 1 | 0 | 0 |
23 | 1 | 0 | 0 | 1 | 1 | 1 | 1 | 1 | 0 | 1 |
24 | 0 | 1 | 0 | 1 | 1 | 1 | 1 | 0 | 1 | 0 |
25 | 1 | 1 | 0 | 1 | 1 | 1 | 1 | 0 | 0 | 1 |
26 | 0 | 0 | 1 | 1 | 1 | 1 | 0 | 0 | 1 | 0 |
27 | 1 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 0 | 0 |
28 | 0 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 0 |
29 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 | 1 |
30 | 0 | 0 | 0 | 0 | 0 | 1 | 0 | 0 | 0 | 0 |
31 | 0 | 0 | 0 | 0 | 1 | 1 | 1 | 0 | 0 | 0 |
Low many of the error rate that hard decision obtains.
According to 3GPP agreement regulation, work as N simultaneously
TPCEqual at 2 o'clock, stipulate that from agreement two TPC symbols are identical as can be known, 11 expression power control commands, 1,00 expression power control command 0.Therefore the result after we can merge high specific carries out earlier on average, and then carries out hard decision.Suppose that transmit signal power is
Noise is a variances sigma
2=N
0/ 2 Gauss is variable immediately, and then the error rate of signal is
p
e=Q[(2E
s/N
0)
1/2]
In the formula
Owing to be averaged, noise variance becomes σ
2=N
0/ 4, the TPC error rate also can descend.
Therefore by TFCI and TPC being adopted different decoding processes can reduce the error rate of non-pilot signal greatly respectively, so just can improve the accuracy of channel estimating, improve the entire system performance.Below we describe the process of whole channel estimating in detail.
1, the structure of Rake receiver is at first sent into Multipath searching demodulation module 401 from the data of antenna opening as shown in Figure 4.In this module, from baseband signal, search for multipath, find out the time delay of each multipath, and carry out demodulation respectively according to each footpath time delay respectively, obtain the DPCCH and the DPDCH component in each footpath.The Dedicated Physical Control Channel in each footpath is sent to channel estimation module 402, simultaneously Dedicated Physical Control Channel and Dedicated Physical Data Channel is sent into high specific merging module 403.
2, in channel estimation module 402, according to the Dedicated Physical Control Channel of input calculate the channel estimation value in each footpath, these values are sent to high specific merge module 403.In high specific merging module, utilize each footpath channel estimation value of input, each Dedicated Physical Data Channel and control channel is directly carried out the high specific union operation, obtain the result of Dedicated Physical Data Channel and control channel.Channel estimation module 402 is main bodys of the present invention.
3, there is M bar footpath in supposition, corresponds respectively to M Dedicated Physical Control Channel component DPCCH
1..., DPCCH
MChannel estimation module wherein exists M bar passage as shown in Figure 6, is example explanation idiographic flow with passage 1 here.Article one, Jing Dedicated Physical Control Channel component DPCCH
1Send into pilot tone, TFCI and TPC signal separation module 421, with the various Signal Separation in the time slot.Pilot signal is sent in the multiplier 422 and known local pilot signal multiplies each other, and so just removes the information of pilot tone, obtains pilot tone envelope Pilot
Channel
4, with pilot tone envelope Pilot
ChannelBe sent to the first initial channel estimation module 423, now generally use the method for initial channel estimation that the method for average is arranged, methods such as single order, second order interpolation method and prediction.Consider algorithm complex, adopt average method to obtain the first channel estimation value Pilot_est here
Channel
5, with Pilot_est
ChannelConjugation and TFCI signal be sent in the multiplier 424 (first multiplier), conjugate multiplication obtains the channel compensation component of TFCI.Then this channel compensation component is delivered to adder 425 (first adder), TFCI symbol judgement module 426 has been delivered in the channel compensation component addition of the TFCI in each footpath, and TFCI is carried out symbol judgement.
6, TFCI symbol judgement module as shown in Figure 7, zero padding module 4260 is at first collected the TFCI merging value of 15 time slots in the frame
Adding two zero for then this ordered series of numbers back, to obtain length be 32 ordered series of numbers.This ordered series of numbers is sent to quick Ha Mada conversion module 4261, obtains TFCI information sequence a by the Ha Mada conversion
0, a
1..., a
9Decoded result delivers to TFCI encoder 4262, and decoded information sequence is encoded again obtains b
0, b
1..., b
31Preceding 30 symbols are divided into 15 groups and send in 15 corresponding time slots and go in the TFCI symbol that newly obtains.
7, the TFCI that obtains of TFCI signal and judgement delivers in the multiplier 427 (second multiplier), removes the information of TFCI, obtains TFCI envelope TFCI
ChannelWith pilot tone envelope Pilot
ChannelWith TFCI envelope TFCI
ChannelAll deliver to the second initial channel estimation module 428, adopt average method to obtain the second channel estimation value Pilot_TFCI_est
Channel
8, with Pilot_TFCI_est
ChannelConjugation and TPC signal be sent in the multiplier 429 (the 3rd multiplier), conjugate multiplication obtains the channel compensation component of TPC.Then this channel compensation component is delivered to adder 42D (second adder), TPC symbol judgement module 42A has been delivered in the channel compensation component addition of the TPC in each footpath, and TPC is carried out symbol judgement.
9, TPC symbol judgement module as shown in Figure 8, the TPC signal TPC after the merging
0, TPC
1Be sent to mean value module 42A1, obtain mean value TPC
MeanMean value is sent to hard decision module 42A2 obtains TPC value TPC_e, obtain TPC_e0, TPC_e1 through replicated blocks 42A3.
10, the TPC symbol TPC_e0 that obtains of TPC signal and judgement, TPC_e1 delivers among the multiplier 42C (the 4th multiplier), removes the information of TPC, obtains TPC envelope TPC
Channel
11, with pilot tone envelope Pilot
Channel, TPC envelope TPC
ChannelWith TFCI envelope TFCI
ChannelAll deliver to channel estimation module 42B, by moving average, adaptive filter method carries out channel estimating, just can obtain the more accurate channel estimation value Pilot_TFCI_TPC_est in this footpath.
Because at non-frequency pilot sign TFCI, the difference of TPC coded system adopts different decoding processes among the present invention, compare with direct hard decision, can reduce the error rate of non-pilot signal greatly.By improving the accuracy of channel estimating, can improve systematic function on the whole.
Claims (10)
1, a kind of half-blind channel estimating method of broadband CDMA system is characterized in that, may further comprise the steps:
(1) the Dedicated Physical Control Channel component in each footpath is sent into pilot tone, transformat combination indication and transmitting power control signal separation module, with the various Signal Separation in the time slot;
(2) the pilot tone envelope is sent to the first initial channel estimation module and obtains first channel estimation value;
(3) conjugation and the transformat combination index signal with first channel estimation value is sent in first multiplier, and conjugate multiplication obtains the channel compensation component of transformat combination indication;
(4) the transport format combination indicator judging module is delivered in the channel compensation component addition of the transformat combination in each footpath indication, and symbol judgement is carried out in indication to transformat combination;
(5) the transformat combination index signal is all delivered in second multiplier with the transformat combination index signal that judgement obtains, obtain transformat combination indication envelope, pilot tone envelope and transformat combination indication envelope are all delivered to the second initial channel estimation module obtain second channel estimation value;
(6) conjugation and the transmitting power control signal with second channel estimation value is sent in the 3rd multiplier, conjugate multiplication obtains the channel compensation component of transmitting power control, transmitting power control character judging module is delivered in the channel compensation component addition of the transmitting power control in each footpath, and symbol judgement is carried out in control to transmitting power;
(7) the transmitting power control signal is all delivered in the 4th multiplier with the transmitting power control character that judgement obtains, and obtains transmitting power control envelope;
(8) with the pilot tone envelope, transmitting power control envelope and transformat combination indication envelope are all delivered to channel estimation module, obtain the channel estimation value in each footpath.
2, method according to claim 1 is characterized in that, the indication to transformat combination in the step (4) is carried out symbol judgement and be may further comprise the steps:
(I) the zero padding module is at first collected the transformat combination indication merging value of 15 time slots in the frame
Adding two zero for then this ordered series of numbers back, to obtain length be 32 ordered series of numbers;
(II) this ordered series of numbers is sent to quick Ha Mada conversion module, obtains transformat combination indication information sequence a by the Ha Mada conversion
0, a
1..., a
9
(III) decoded result delivers to transformat combination indication encoder, and decoded information sequence is encoded again obtains b
0, b
1..., b
31, preceding 30 symbols are divided into 15 groups and send in 15 corresponding time slots and go in the transport format combination indicator that newly obtains number.
3, method according to claim 1 and 2 is characterized in that, the control to transmitting power in the step (6) is carried out symbol judgement and be may further comprise the steps:
(a) the transmitting power control signal after the merging is sent to the mean value module, obtains mean value;
(b) mean value is sent to the hard decision module and obtains the transmitting power controlling value;
(c) the transmitting power control character that obtains adjudicating through replicated blocks.
4, method according to claim 1, it is characterized in that: the data from antenna opening are at first sent into the Multipath searching demodulation module, in this module, from baseband signal, search for multipath, find out the time delay of each multipath, and carry out demodulation respectively according to each footpath time delay respectively, obtain the Dedicated Physical Control Channel and the Dedicated Physical Data Channel component in each footpath.
5, method according to claim 1, it is characterized in that: utilize each footpath channel estimation value, Dedicated Physical Data Channel and Dedicated Physical Control Channel to each footpath carry out the high specific union operation, obtain the result of Dedicated Physical Data Channel and Dedicated Physical Control Channel.
6, the Rake receiver in a kind of mobile communication system is characterized in that, comprises channel estimation module, is used to calculate the channel estimation value in each footpath, and this channel estimation module is by forming with the lower part:
Pilot tone, transformat combination indication and transmitting power control signal separation module are used for the various Signal Separation with time slot;
The first initial channel estimation module utilizes the pilot tone envelope of input to obtain first channel estimation value;
First multiplier is used for the conjugation of first channel estimation value and transformat combination index signal and multiplies each other and obtain the channel compensation component of transformat combination indication;
First adder, the channel compensation component that the transformat combination in each footpath is indicated carries out addition;
The transport format combination indicator judging module, utilize addition the channel compensation component of transformat combination indication in each footpath to transformat combination indication carry out symbol judgement;
Second multiplier is used for transformat combination indication that transformat combination index signal and judgement obtain and multiplies each other and obtain transformat combination indication envelope;
The second initial channel estimation module utilizes pilot tone envelope and transformat combination indication envelope to adopt average method to obtain second channel estimation value;
The 3rd multiplier, the conjugation of second channel estimation value and transmitting power control signal multiplied each other obtains the channel compensation component of transmitting power control;
Second adder is with the channel compensation component addition of each transmitting power control directly;
Transmitting power control character judging module, utilize addition the channel compensation component of transmitting power control to transmitting power control carry out symbol judgement;
The 4th multiplier, the transmitting power control character that utilizes transmitting power control signal and judgement to obtain obtain transmitting power control envelope;
Channel estimation module utilizes the pilot tone envelope, and transmitting power control envelope and transformat combination indication envelope adopt moving average, and adaptive filter method carries out the channel estimation value that channel estimating obtains each footpath.
7, receiver according to claim 6 is characterized in that, described transport format combination indicator judging module is by forming with the lower part:
The zero padding module, the transformat combination indication merging value of collecting 15 time slots in the frame
Adding two zero for then this ordered series of numbers back, to obtain length be 32 ordered series of numbers;
The Ha Mada conversion module obtains transformat combination indication information sequence a to the output of zero padding module by the Ha Mada conversion fast
0, a
1..., a
9
Transformat combination is indicated encoder, and the decoded information sequence of quick Ha Mada conversion module output is encoded again obtains b
0, b
1..., b
31
According to claim 6 or 7 described receivers, it is characterized in that 8, described transmitting power control character judging module is by forming with the lower part:
The mean value module utilizes the transmitting power control signal after merging to obtain mean value;
The hard decision module utilizes the output of mean value module to obtain the transmitting power controlling value;
Replicated blocks, the transmitting power control character that utilizes the output of hard decision module to obtain adjudicating.
9, receiver according to claim 6, it is characterized in that, also comprise the Multipath searching demodulation module, in this module, from baseband signal, search for multipath, find out the time delay of each multipath, and carry out demodulation respectively according to each footpath time delay respectively, obtain the Dedicated Physical Control Channel and the Dedicated Physical Data Channel component in each footpath.
10, receiver according to claim 6, it is characterized in that, comprise that also high specific merges module, utilize each footpath channel estimation value of input, Dedicated Physical Data Channel and Dedicated Physical Control Channel to each footpath carry out the high specific union operation, obtain the result of Dedicated Physical Data Channel and Dedicated Physical Control Channel.
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CN103731378B (en) * | 2012-10-10 | 2017-05-10 | 京信通信系统(中国)有限公司 | Method and device for managing frequency deviation |
CN109831396B (en) * | 2019-03-07 | 2021-05-18 | 西安电子科技大学 | Semi-blind channel estimation method of short burst MIMO communication system |
CN111082902B (en) * | 2019-11-12 | 2022-05-17 | 杭州电子科技大学 | Large-scale antenna system signal detection method based on big data statistical characteristics |
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CN1327316A (en) * | 2000-06-01 | 2001-12-19 | 华为技术有限公司 | Anti-deep attenuation semi-blind channel evaluation method in wide band code division multiple access |
US6700919B1 (en) * | 1999-11-30 | 2004-03-02 | Texas Instruments Incorporated | Channel estimation for communication system using weighted estimates based on pilot data and information data |
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US6700919B1 (en) * | 1999-11-30 | 2004-03-02 | Texas Instruments Incorporated | Channel estimation for communication system using weighted estimates based on pilot data and information data |
CN1327316A (en) * | 2000-06-01 | 2001-12-19 | 华为技术有限公司 | Anti-deep attenuation semi-blind channel evaluation method in wide band code division multiple access |
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