CN102469050B - Chanel estimating method in long-term evolution system based on specific reference signal of terminal - Google Patents

Abstract

The invention relates to a channel estimating method, particularly to a channel estimating method in a long-term evolution system based on a specific reference signal of a terminal. The invention discloses a channel estimating method in a long-term evolution LTE system based on a specific reference signal of a terminal, wherein the method comprises the steps of: estimating the channel of subcarriers at the reference signal by the specific reference signal UE-specific RS of the terminal on a distributed resource blocks according to the distribution conditions of the resource block users; filling the channel estimating value of the reference signal of the undistributed resource block based on the channel estimating value of the subcarrier at the reference signal; and estimating the channel of the data subcarrier according to the channel estimating value on the reference signal subcarrier on the processed full bandwidth. By the method disclosed by the invention, the channel estimating and processing process is in accordance with that of the specific reference signal of cell, and the complexity on further treatment and control can be reduced.

Description

In the long evolving system based on the channel estimation methods of terminal-specific reference signal

Technical field

The present invention relates to channel estimation methods, relate in particular in Long Term Evolution (LTE, the Long Term Evolution) system channel estimation methods based on terminal-specific reference signal (UE-specific RS).

Background technology

At Long Term Evolution (LTE, Long Term Evolution) in the system, owing to taked OFDM (OFDM, Orthogonal Frequency Division Multiplexing) technology is as its key technology, need to do channel estimating by cell-specific (Ce11-specific) and special-purpose (UE-specific) reference signal of user (RS), but in the LTE system, UE-specific reference signal and Ce11-specific reference signal are different in the distribution mode on the system bandwidth: the Ce11-specific reference signal is continuous distribution on system bandwidth, and the UE-specific reference signal may be according to the different situations that discontinuous distribution occurs of the configuration of user bandwidth, the common scheme of in the industry the UE-specific reference signal being carried out channel estimating is that the UE-specific reference signal is processed separately, but such way can cause having two cover handling processes, namely independent Processing Interface need to be arranged respectively and process function for channel estimating Ce11-specific and UE-specific, can increase like this complexity of physical layer process and control.

Summary of the invention

Main purpose of the present invention provides in a kind of LTE system channel estimation methods based on the terminal-specific reference signal, thereby realize that terminal-specific reference signal channel estimating is consistent with cell special reference channel estimation process flow process, reduce the complexity of subsequent treatment and control.

Based on the channel estimation methods of terminal-specific reference signal, comprising in a kind of LTE system:

According to Resource Block user assignment situation, for the Resource Block that has distributed, utilize the UE-specific reference signal of carrying on the described Resource Block, the subcarrier at described reference signal place is carried out channel estimating;

For unappropriated Resource Block, utilize the channel estimation value of the subcarrier at described reference signal place, the reference signal channel estimation value of described unappropriated Resource Block is filled processing;

Utilize the channel estimation value on the reference signal subcarrier on the full bandwidth after processing, the data subcarrier is carried out channel estimating.

Preferably, described according to Resource Block user assignment situation, for the Resource Block that has distributed, utilize the terminal-specific reference signal UE-specific RS that carries on the described Resource Block, before the subcarrier at described reference signal place carried out channel estimating, also comprise and utilize Downlink Control Information DCI to obtain Resource Block user assignment situation, described Resource Block user assignment situation includes but not limited to: continuous Resource Block number m in the number NRB of the Resource Block that has distributed, the Resource Block of distribution, and continuous resource piece position indication P ₁, P ₂... P _i... P _m, P wherein _i, i=1,2 ... m represents respectively the distributing position indication of i continuous resource piece on full bandwidth.

Preferably, the described UE-specific reference signal of carrying on the described Resource Block of utilizing, the subcarrier at described reference signal place is carried out channel estimating to be specially: to the UE-specific reference signal on the described distributes resource blocks, use least square method or least mean-square error to obtain the channel estimation value at UE-specific reference signal place

Preferably, to the UE-specific reference signal on the described Resource Block that has distributed, the channel estimation value that uses least square method to obtain UE-specific reference signal place is specially: by the frequency domain UE-specific reference signal P of this locality generation _Tx(k), k=0,1 ..., K-1 and the actual frequency domain UE-specific reference signal p that receives _Rx(k), k=0,1 ..., K-1, wherein K represents the quantity of UE-specific reference signal subcarrier, obtains the channel estimation sequence of K UE-specific reference signal position, that is:

${\hat{H}}_{\mathrm{LS}}\left(k\right)=\frac{p_{\mathrm{rx}}\left(k\right)}{p_{\mathrm{tx}}\left(k\right)}$ k＝0，1，…K-1°

Preferably, described for unappropriated Resource Block, utilize the channel estimation value of the subcarrier at described reference signal place, described reference signal channel estimation value is filled to process be specially:

As described worker P _iAnd P _I+1(i=1 ..., in the vacant situation that equals a Resource Block, adopt by P between m) _I+1In the mode of the channel estimation value of the reference signal on the vacant Resource Block being filled from the channel estimation results of a nearest reference signal of filling position;

As described P _iAnd P _I+1Between in the vacant situation more than or equal to 2 Resource Block, adopt near P _iResource Block with the P of close rest position _iThe channel estimation value of reference signal fill, near P _I+1Resource Block with the P of close position _I+1The channel estimation value of reference signal fill, the Resource Block of all the other positions is filled 0 mode.

Preferably, work as P ₁Perhaps P _mNot in the beginning and end position of system bandwidth, then for close P ₁The Resource Block of position is by the P of close rest position ₁The channel estimation value of reference signal fill; For close P _mThe Resource Block of position is by the P of close rest position _mThe channel estimation value of reference signal fill.

Preferably, utilize the channel estimation value on the reference signal subcarrier on the full bandwidth after processing, the data subcarrier is carried out channel estimating, be specially: utilize the sliding window algorithm to carry out frequency domain linear minimum mean-squared error channel estimating.

Preferably, describedly utilize the sliding window algorithm to carry out frequency domain linear minimum mean-squared error channel estimating to may further comprise the steps:

Obtain the block count of sliding window according to the number NRB of the Resource Block that has distributed;

According to the block count of the long L of sliding window and described sliding window, calculate the sub-carrier channels estimated value of each piecemeal;

Channel estimation value to subcarrier on the full bandwidth that obtains merges processing.

Preferably, described to the full bandwidth that obtains on the channel estimation value of subcarrier also comprise before merging processing, obtain the channel estimation value of edge subcarrier, be specially: according to the position skew of first UE-specific reference signal that calculates, copy the channel estimation value of first UE-specific reference signal, obtain the channel estimation value of edge subcarrier.

Preferably, described block count according to the long L of sliding window and described sliding window, the sub-carrier channels estimated value of calculating each piecemeal is specially, wherein:

Calculate the channel estimation value of a front 2*L-3 subcarrier of first piecemeal;

Block count according to described sliding window calculates the middle sub-carrier channels estimated value of each sliding window;

Calculate the channel estimation value of last 2*L-1 subcarrier of last piecemeal; The present invention is by the distribution condition according to Resource Block, for the reference signal channel estimation value on the unappropriated Resource Block, utilize the sub-carrier channels estimated value of the reference signal of carrying on the Resource Block that has distributed to fill processing, solved the discontinuously arranged problem of terminal-specific reference signal, and the channel estimation value on the reference signal subcarrier on the full bandwidth after the utilization processing, the data subcarrier is carried out channel estimating, realize the channel estimation process flow process consistent with cell special reference, reduced the complexity of subsequent treatment and control.Simultaneously, the filling of the reference signal channel estimation value on the unappropriated Resource Block is processed, can be avoided the bottle end effect of the filling mode high s/n ratio appearance of direct zero filling, reach more dominance energy.

Description of drawings

Fig. 1 is based on the channel estimation methods schematic flow sheet of terminal-specific reference signal in the LTE of the present invention system;

Fig. 2 is based on the channel estimation methods flow chart of terminal-specific reference signal in the LTE system that provides of an embodiment of the present invention;

Fig. 3 is sliding window algorithm schematic diagram;

Fig. 4 is the mapping graph of terminal-specific reference signal under common and extended cyclic prefix;

Fig. 5 is the performance comparison diagram that an embodiment of the present invention provides.

Embodiment

Below in conjunction with specific embodiment and accompanying drawing to further setting forth based on the channel estimation methods of terminal-specific reference signal in the LTE of the present invention system, so that spirit of the present invention, technical characterictic and effective effect are easier to understand.

Based on the channel estimation methods schematic flow sheet of terminal-specific reference signal as shown in Figure 1, core technology scheme of the present invention is in the LTE of the present invention system:

S101, according to Resource Block user assignment situation, for the Resource Block that has distributed, utilize the UE-specific reference signal of carrying on the described Resource Block, the subcarrier at described reference signal place is carried out channel estimating;

S102, for unappropriated Resource Block, utilize the channel estimation value of the subcarrier at described reference signal place, the reference signal channel estimation value of described unappropriated Resource Block is filled processing;

Channel estimation value on the full bandwidth after S103, utilization are processed on the reference signal subcarrier carries out channel estimating to the data subcarrier.

Wherein, as a kind of execution mode, before step S101, also comprise, utilize Downlink Control Information (DCI, Downlink Control information) obtain Resource Block user assignment situation, described Resource Block user assignment situation includes but not limited to: continuous Resource Block number m in the number NRB of the Resource Block that has distributed (PRB), the Resource Block of distribution, and continuous resource piece position indication P ₁, P ₂... P _i... P _m, P wherein _iRepresent respectively the distributing position of i continuous resource piece on full bandwidth.P ₁, P ₂... P _i... P _mBe that PRB ascending order direction distributes in the full bandwidth scope.I=1 wherein, 2 ... m.

As execution mode further, step S101 is specially, and to the UE-specific reference signal on the described Resource Block that has distributed, uses least square method or least mean-square error to obtain the channel estimation value at UE-specific reference signal place

Step S101 further is, by the frequency domain UE-specific reference signal p of this locality generation _Tx(k), k=0,1 ..., K-1 and the actual frequency domain UE-specific reference signal p that receives _Rx(k), k=0,1 ..., K-1, wherein K represents the quantity of UE-specific reference signal subcarrier, obtains the channel estimation sequence of K UE-specific reference signal position, that is:

${\hat{H}}_{\mathrm{LS}}\left(k\right)=\frac{p_{\mathrm{rx}}\left(k\right)}{p_{\mathrm{tx}}\left(k\right)}$ k＝0，1，…K-1

Filling processing mode among the step S102 has three kinds of situations:

In the situation of regular circulation prefix (Normal CP),

Situation one: work as P _iAnd P _I+1(i=1 ..., m) (P _iBe i continuous resource piece in the indication of the distributing position on the full bandwidth) between in the vacant situation that equals a Resource Block (PRB), adopt by P _I+1In the mode of the channel estimation value of the reference signal on the vacant Resource Block being filled from the channel estimation results of a nearest reference signal of filling position;

Situation two: work as P _iAnd P _I+1Between in the vacant situation more than or equal to 2 Resource Block, adopt by near P _iResource Block with the P of close rest position _iThe channel estimation value of reference signal fill, near P _I+1Resource Block with the P of close position _I+1The channel estimation value of reference signal fill, the Resource Block of all the other positions is filled 0 mode.

Situation three: work as P ₁Perhaps P _mNot in the beginning and end position of system bandwidth, then for close P ₁The Resource Block of position is by the P of close rest position ₁The channel estimation value of reference signal fill; For close P _mThe Resource Block of position is by the P of close rest position _mThe channel estimation value of reference signal fill.

In the situation of extended cyclic prefix (extended CP), difference is, resource particle (RE, the Resource Element) number that the reference signal among PRB takies is 4, and padding scheme is consistent with the situation of Normal CP.

Step S103 is specially:

Utilize the sliding window algorithm to carry out frequency domain linear minimum mean-squared error channel estimating.Further may further comprise the steps:

The number NRB of the Resource Block (PRB) that S1031, basis have been distributed obtains the block count of sliding window;

S1032, according to the block count of the long L of sliding window and described sliding window, calculate the sub-carrier channels estimated value of each piecemeal;

S1033, the channel estimation value of subcarrier on the full bandwidth that obtains is merged processing.

Wherein before step S1033, also comprise: according to the position skew of first UE-specific reference signal that calculates, copy the channel estimation value of first UE-specific reference signal, obtain the channel estimation value of edge subcarrier.

Wherein S1032 is specially:

Calculate the channel estimation value of a front 2*L-3 subcarrier of first piecemeal;

Calculate the channel estimation value of each sliding window dynatron carrier wave according to the block count of described sliding window;

Calculate the channel estimation value of last 2*L-1 subcarrier of last piecemeal.

Wherein L represents that the window of sliding window is long, as can be seen from Figure 4, the distribution situation of UE-specific reference signal on Resource Block, wherein Fig. 4 A is the mapping graph in normal cyclic prefix (in the Normal CP situation), Fig. 4 B is in extended cyclic prefix (in the Extended CP situation).According to the sliding window schematic diagram of Fig. 3, in first piecemeal, because there is not reference signal in the front, so the sub-carrier channels estimated value of first piecemeal is determined by the reference signal of rear adjacent.Length at first piecemeal of normal cyclic prefix (in the Normal CP situation) is defined as 2*L-3, is 2*L-2 under extended cyclic prefix, the number of data subcarrier between the 3 and 2 expression UE-specific reference signals that wherein deduct.

As can be seen from Figure 4, in Normal CP situation, a PRB has three RE, the UE-specific reference signal takies, be spaced apart 3 RE between the UE-specific reference signal, so each sliding window can estimate the value of 3 data subcarriers and a UE-specific reference signal, then calculate the channel value of 4 subcarriers in centre of each sliding window.In like manner in extended CP situation, then calculate the channel value of 3 subcarriers in centre of each sliding window.

In order to make those skilled in the art can clearerly understand the technical scheme that the embodiment of the invention provides, below by a preferred embodiment UE-specificc reference signal channel estimating of the present invention is described in detail.The UE-specific of channel estimating meets the physical layer standard 3GPP TS36.211V8.7.0 of LTE in the present embodiment, and pattern is single antenna 5MHz bandwidth, and residential quarter ID is 2, and Cyclic Prefix is the regular circulation prefix.

S201, according to Resource Block user assignment situation, for the Resource Block that has distributed, utilize the UE-specific reference signal of carrying on the described Resource Block, the subcarrier at described reference signal place is carried out channel estimating.

Wherein, this step specifically comprises following two steps:

S2011, utilize Downlink Control Information (DCI, Downlink Control information) obtains Resource Block user assignment situation, described Resource Block user assignment situation includes but not limited to: continuous Resource Block number m in the number NRB of the Resource Block that has distributed, the Resource Block of distribution, and continuous resource piece position indication P ₁, P ₂... P _i... P _m, P wherein ₁P _mRepresent respectively the distribution situation of m continuous resource piece.

In the present embodiment, the number NRB of the Resource Block that has distributed is 25, and the Resource Block binary representation form of distribution is 1110111100110.Because bandwidth is 5MHZ, according to 3GPP TS 36.213V8.7.0, then two continuous PRB are for consisting of a Resource Block (RBG) group, a bit represents 2 PRB in the binary representation form then, so can obtain, continuous Resource Block number m is 3 in the Resource Block that distributes, and arranges according to ascending order, then supposes P ₃Expression 111, P ₂Expression 1111, P ₁Expression 11.

Reference signal channel estimation value on S2012, the dispensed Resource Block, account form are the UE-specific reference signal p that produces by this locality _Tx(k), k=0,1 ..., K-1 and the actual frequency domain UE-specific reference signal p that receives _Rx(k), k=0,1 ..., K-1, wherein K represents the quantity of reference signal subcarrier, obtains the channel estimation value of K UE-specific reference signal position, that is:

${\hat{H}}_{\mathrm{LS}}\left(k\right)=\frac{p_{\mathrm{rx}}\left(k\right)}{p_{\mathrm{tx}}\left(k\right)}$ k＝0，1，…K-1

S202, for unappropriated Resource Block, utilize the channel estimation value of the subcarrier at described reference signal place, the reference signal channel estimation value of described unappropriated Resource Block is filled processing;

In the present embodiment, at P ₃And P ₂Between have RBG group to be not yet assigned to the user because bandwidth is 5MHZ, a RBG group represents two PRB, then P ₃And P ₂Between two PRB are arranged, near P ₁The UE-sepecifc reference signal of the unappropriated Resource Block of end is with the P of close rest position ₁The channel estimation value of reference signal fill, another unappropriated UE-specific reference signal is with the P of close rest position ₂The channel estimation value of reference signal fill.

At P ₂And P ₁Between have two RBG group to be not yet assigned to the user, have 4 PRB to be not yet assigned to the user in the middle of then, to respectively near P ₂And P ₁Two PRB fill by above-mentioned steps, two PRB of centre are filled 0.

Because the P that distributes ₁Not in the original position of system bandwidth.Near P ₁The place also have a RBG (Resource Block group) to be not yet assigned to the user, so near P ₁PRB, with the P of close rest position ₁The channel estimation value of reference signal this PRB reference signal position is filled.The value at another one PRB reference signal place fills 0.

Fig. 5 is in the present embodiment, the performance comparison diagram of different filling processing methods., can find out that on scheming the padding scheme that adopts present embodiment to provide than the scheme of direct filling 0, interval than high s/n ratio, has obvious throughput performance difference.

The number NRB of the Resource Block that S203, basis have been distributed obtains the block count block of sliding window.

In above-mentioned steps, adopt the sliding window algorithm to be that according to linear minimum mean-squared error (Linear Minimum Mean-Square Error, LMMSE) algorithm, the channel estimation value at data subcarrier place can be expressed as follows at frequency domain: ${\hat{H}}_{\mathrm{LMMSE}}=R_{{\mathrm{HH}}_p}{(R_{H_p{H}_p}+{\mathrm{\σ}}^2{\left(X^{H}X\right)}^{-1})}^{-1}{\hat{H}}_{\mathrm{LS}},$

The channel value that expression takes the LMMSE algorithm to estimate.

The cross-correlation matrix that represents the subcarrier at subcarriers all on the frequency domain and pilot tone place,

The autocorrelation matrix of pilot tone virgin carrier wave on the expression frequency domain.

As can be seen from the above equation, estimate that with the LMMSE algorithm H amount of calculation is very large.For example, estimate that at every turn H needs to calculate

This amount of calculation is just very large, and also comprises in this matrix inversion

Being an expression of expression channel power delay spectrum (PDP, Power Delay Profile), is a statistic, therefore fixes in for a long time.If the sign map of transmission is to same planisphere, so (XX ^H) ^-1Can be with its Expectation-based Representation for Concepts: ${\mathrm{\σ}}_w^2{\left({\mathrm{XX}}^H\right)}^{-1}=E\left\{{\mathrm{\σ}}_w^2{\left({\mathrm{XX}}^H\right)}^{-1}\right\}=I_{N_p}\frac{\mathrm{\β}}{\mathrm{SNR}}$

β=E{|X wherein _k| ²E{1/|X _k| ², X _kFor the point on the planisphere, for QPSK, β=1, for 16QAM, β=17/9.Formula so ${\hat{H}}_{\mathrm{LMMSE}}=R_{{\mathrm{HH}}_p}{(R_{H_p{H}_p}+{\mathrm{\σ}}^2{\left(X^{H}X\right)}^{-1})}^{-1}{\hat{H}}_{\mathrm{LS}}$ Can be expressed as:

${\hat{H}}_{\mathrm{LMMSE}}=R_{{\mathrm{HH}}_p}{(R_{H_p{H}_p}+I_{N_p}\frac{\mathrm{\β}}{\mathrm{SNR}})}^{-1}{\hat{H}}_{\mathrm{LS}}.$

In a fixing channel circumstance, the correlation of subcarrier and other subcarriers only and the distance dependent between the two system, the nearlyer correlation of distance is larger, distance correlation far away is less, therefore when estimating the channel value of a certain data subcarrier, only adopt the channel value of several pilot tones nearest with it to carry out LMMSE and estimate to get final product, so just can reduce greatly operand.So, multiple possible channel and noise factor are preseted, will

Calculate and preserve, so only need to select different Q matrixes and LS algorithm to estimate according to the root mean square (r.m.s) of the channel delay expansion that estimates with the signal to noise ratio of estimating

Multiply each other and can obtain the interior channel estimation value of frequency domain:

With

Respectively N * N _pAnd N _p* N _pMatrix, so the Q matrix is a N * N _pMatrix.Owing to take the mode of sliding window, can get less N value and N _pValue has reduced operand.The long selective basis actual conditions of sliding window window need to be traded off between performance and complexity.In the present embodiment, the length of getting sliding window is 4 RS.

In the present embodiment, Block=3*NRB-3, the NRB value is 25, so the Block value is 72.

S204, calculate the channel estimation value of a front 2*L-3 subcarrier of first piecemeal;

The length of sliding window is 4 RS in the present embodiment, and namely L=4 brings formula 2*L-3 into, then obtains needing to calculate the channel estimation value of first 5 subcarriers in piecemeal front,

$H1\left[k\right]=\mathrm{Qf}\left[k\right][0:3]*{\hat{H}}_{\mathrm{LS}}{[0:3]}^T,k=0:4.$

S205, calculate the channel estimation value of each sliding window dynatron carrier wave according to the described block count that calculates;

According to 3GPP TS 36.211 V8.7.0, there are three RE to be taken by the UE-specific reference signal among the PRB, be spaced apart 3 RE between the reference signal, so each sliding window can estimate the channel estimation value of 3 data subcarriers and a UE-specific reference signal, so calculate the channel estimation value of 4 subcarriers in centre of each sliding window $H1[5+4*i+k]=\mathrm{Qf}[5+k][0:3]*{\hat{H}}_{\mathrm{LS}}{[i:i+3]}^T,k=0:3.$

S206, judged whether last piecemeal, if do not arrive, continued to carry out S205, otherwise forward S207 to.

S207, calculate the channel estimation value of last 2*L-1 subcarrier of last piecemeal;

In the present embodiment, L=4,2*L-1=7 then namely calculates the channel estimation value of last 7 subcarriers.

$H_1[12*\mathrm{NRB}-7+k]=\mathrm{Qf}[9+k][0:3]*{\hat{H}}_{\mathrm{LS}}{[3*\mathrm{NRB}-4:3*\mathrm{NRB}-1]}^T,k=0:6$

S208, the channel estimation value of subcarrier on the full bandwidth that obtains is merged processing.

Wherein, step S208 specifically comprises:

S2081, according to residential quarter ID number

Calculate the side-play amount shift of reference signal with OFDM notation index l;

Under general cyclic prefix: the side-play amount shift of the resource particle that the UE-specific reference signal takies (Resource Element, RE) in a PRB can be expressed as: in different l situations, and shift=v _ShiftPerhaps shift=(2+v _Shift) mod 4, suppose in the present embodiment that l=3 calculates shift value on the 3rd the OFDM symbol.Because

Be 2, then according to shift=v _Shift, shift is 2.

The Ue-specific reference signal value that channel estimation value on S2082, the edge subcarrier is taked to close on most copies.

The edge subcarrier is the data subcarrier before first terminal-specific reference signal among first PRB in the full bandwidth.Namely according to the side-play amount of first UE reference signal that calculates, copy the channel estimation value of first UE reference signal, obtain the channel estimation value of edge subcarrier.In the present embodiment, shift is 2, and then the channel estimation value of two the edge subcarriers in front is the channel estimation value of first UE reference signal, H[0:shift-1]=H1[0] because shift is 2, H[0:1 then]=H1[0]

S2083, the channel estimation value on the edge subcarrier and the channel estimation value that utilizes sliding window to calculate are merged, obtain the channel estimation value of subcarrier on the full bandwidth.Be H[shift:12*NRB-1]=H1[0:12*NRB-1-shift].Shift=2 is brought into, obtain the channel estimation value in the whole bandwidth range.H[2:12*NRB-1]＝H1[0:12*NRB-1-2]。H[0:12*NRB-1 wherein] the final channel estimation value of expression.

As seen, in a kind of LTE provided by the invention system based on the channel estimation methods of terminal-specific reference signal, by the distribution condition according to Resource Block, for unappropriated Resource Block, utilize the sub-carrier channels estimated value of the reference signal of carrying on the Resource Block that has distributed to carry out channel estimation value filling processing, solved the discontinuously arranged problem of terminal-specific reference signal, and the channel estimation value on the reference signal subcarrier on the full bandwidth after the utilization processing, the data subcarrier is carried out channel estimating, realize the channel estimation process flow process consistent with cell special reference, reduced the complexity of subsequent treatment and control.

Those of ordinary skill in the art is clear and understanding obviously, in a kind of LTE of the present invention system based on the channel estimation methods of terminal-specific reference signal for above embodiment only be used for a kind of LTE of explanation the present invention system based on the channel estimation methods of terminal-specific reference signal, and be not limited in a kind of LTE of the present invention system the channel estimation methods based on the terminal-specific reference signal.Although effectively described in a kind of LTE of the present invention system channel estimation methods based on the terminal-specific reference signal by embodiment, those of ordinary skills know that there are many variations in the channel estimation methods based on the terminal-specific reference signal in a kind of LTE of the present invention system and do not break away from spirit of the present invention.In the situation based on the spirit of the channel estimation methods of terminal-specific reference signal and essence thereof in not deviating from a kind of LTE of the present invention system; but those skilled in the art make various corresponding changes or distortion when the method according to this invention, but these corresponding change or distortion all belongs in a kind of LTE of the present invention system claim protection range based on the channel estimation methods of terminal-specific reference signal.

Claims (8)

1. In the Long Term Evolution LTE system based on the channel estimation methods of terminal-specific reference signal UE-specific RS, it is characterized in that, may further comprise the steps:

   According to Resource Block user assignment situation, for the Resource Block that has distributed, utilize the UE-specific reference signal of carrying on the described Resource Block, the subcarrier at described reference signal place is carried out channel estimating;

   For unappropriated Resource Block, utilize the channel estimation value of the subcarrier at described reference signal place, the reference signal channel estimation value of described unappropriated Resource Block is filled processing;

   Utilize the channel estimation value on the reference signal subcarrier on the full bandwidth after processing, the data subcarrier is carried out channel estimating;

   Described for unappropriated Resource Block, utilize the channel estimation value of the subcarrier at described reference signal place, described reference signal channel estimation value is filled to process be specially:

   As continuous resource piece position indication P _iAnd P _I+1, i=1 ..., in the vacant situation that equals a Resource Block, adopt by P between the m _I+1In the mode of the channel estimation value of the reference signal on the vacant Resource Block being filled from the channel estimation results of a nearest reference signal of filling position, wherein P _i, i=1,2 ... m represents respectively the distributing position indication of i continuous resource piece on full bandwidth;

   As described P _iAnd P _I+1Between in the vacant situation more than or equal to 2 Resource Block, adopt near P _iResource Block with the P of close rest position _iThe channel estimation value of reference signal fill, near P _I+1Resource Block with the P of close rest position _I+1The channel estimation value of reference signal fill, the Resource Block of all the other positions is filled 0 mode;

   Work as P ₁Perhaps P _mNot in the beginning and end position of system bandwidth, then for close P ₁The Resource Block of position is by the P of close rest position ₁The channel estimation value of reference signal fill; For close P _mThe Resource Block of position is by the P of close rest position _mThe channel estimation value of reference signal fill.
2. 2. channel estimation methods as claimed in claim 1, it is characterized in that, described according to Resource Block user assignment situation, for the Resource Block that has distributed, utilize the UE-specific reference signal of carrying on the described Resource Block, before the subcarrier at described reference signal place carried out channel estimating, also comprise and utilize Downlink Control Information DCI to obtain Resource Block user assignment situation, described Resource Block user assignment situation includes but not limited to: continuous Resource Block number m in the number NRB of the Resource Block that has distributed, the Resource Block of distribution, and continuous resource piece position indication P ₁, P ₂P _iP _m
3. 3. channel estimation methods as claimed in claim 2, it is characterized in that, the described UE-specific reference signal of carrying on the described Resource Block of utilizing, the subcarrier at described reference signal place is carried out channel estimating to be specially: to the UE-specific reference signal on the described distributes resource blocks, use least square method or least mean-square error to obtain the channel estimation value at UE-specific reference signal place

   
4. 4. channel estimation methods as claimed in claim 3, it is characterized in that, to the UE-specific reference signal on the described Resource Block that has distributed, the channel estimation value that uses least square method to obtain UE-specific reference signal place is specially: by the frequency domain UE-specific reference signal p of this locality generation _Tx(k), k=0,1 ..., K-1 and the actual frequency domain UE-specific reference signal p that receives _Rx(k), k=0,1 ..., K-1, wherein K represents the quantity of UE-specific reference signal subcarrier, obtains the channel estimation sequence of K UE-specific reference signal position, that is: ${\hat{H}}_{\mathrm{LS}}\left(k\right)=\frac{p_{\mathrm{rx}}\left(k\right)}{p_{\mathrm{tx}}\left(k\right)},k=\mathrm{0,1},\·\·\·K-1.$
5. 5. channel estimation methods as claimed in claim 1, it is characterized in that, utilize the channel estimation value on the reference signal subcarrier on the full bandwidth after processing, the data subcarrier is carried out channel estimating, be specially: utilize the sliding window algorithm to carry out frequency domain linear minimum mean-squared error channel estimating.
6. 6. channel estimation methods as claimed in claim 5 is characterized in that, describedly utilizes the sliding window algorithm to carry out frequency domain linear minimum mean-squared error channel estimating to may further comprise the steps:

   Obtain the block count of sliding window according to the number NRB of the Resource Block that has distributed;

   According to the block count of the long L of sliding window and described sliding window, calculate the sub-carrier channels estimated value of each piecemeal;

   Channel estimation value to subcarrier on the full bandwidth that obtains merges processing.
7. 7. channel estimation methods as claimed in claim 6, it is characterized in that, described to the full bandwidth that obtains on the channel estimation value of subcarrier also comprise before merging processing, obtain the channel estimation value of edge subcarrier, be specially: according to the position skew of first UE-specific reference signal that calculates, copy the channel estimation value of first UE-specific reference signal, obtain the channel estimation value of edge subcarrier.
8. 8. channel estimation methods as claimed in claim 7 is characterized in that, described block count according to the long L of sliding window and described sliding window, and the sub-carrier channels estimated value of calculating each piecemeal is specially, wherein:

   Calculate the channel estimation value of a front 2*L-3 subcarrier of first piecemeal;

   Block count according to described sliding window calculates the middle sub-carrier channels estimated value of each sliding window;

   Calculate the channel estimation value of last 2*L-1 subcarrier of last piecemeal.

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