CN102307167B - Method and device for adjusting uplink timing advance and base station system - Google Patents

Abstract

The invention provides a method for adjusting uplink timing advance, which comprises the following steps: selecting a symbol which is used for frequency domain channel response estimation from PUSCH/PUCCH (physical uplink shared channel/physical uplink control channel); calculating a frequency domain channel response estimated value of the symbol and converting the estimated value to a time domain channel response estimated sequence; carrying out incoherent combination on a power spectrum of the time domain channel response estimated sequence, and selecting a time domain sampling point location corresponding to the maximum peak of the combined power spectrum obtained by the incoherent combination; calculating an offset between the time domain sampling point location and a symbol sequence target location; and adjusting the uplink timing advance according to the offset. The invention also provides a device for adjusting the uplink timing advance. By adopting the technology provided by the invention, more accurate and more precise uplink timing advance can be acquired.

Description

Adjust the method for uplink timing advance, device and base station system

Technical field

The present invention relates to a kind of method, device and the base station system that adjust uplink timing advance, belong to mobile communication technology field.

Background technology

At 3GPP LTE (Long Term Evolution, Long Term Evolution) in system, up each user terminal (User Equipment, be called for short UE) adopt SC-FDMA (single-carrier frequency division multiple access) transmission technology, for ensureing the orthogonality between each UE upward signal, must ensure that each UE upward signal arrives the time consistency of base station receiving terminal, i.e. uplink synchronous, base station adopts different Timing Advances (Timing Advance Command is called for short TA) to realize by controlling each UE.UE comparatively far away for distance base station, propagation delay time is larger, base station adopts larger timing advance TA by instruction UE, the UE comparatively near for distance base station, propagation delay time is less, base station instruction UE adopts less Timing Advance (TA), thus the upward signal of the UE making each far and near position different arrives base station receiving terminal substantially simultaneously.

UE can by initiating Stochastic accessing (Random Access), i.e. PRACH (Physical Random Access Channel), base station receives and after detecting PRACH, accidental access response is sent to UE, up initial TA information is comprised, the Timing Advance of notice UE subsequent upstream transmission in accidental access response.After UE confirms Stochastic accessing success, according to respective obtained initial timing lead, on the basis of down-going synchronous, determine that oneself sends the timing of upward signal, like this, although different UE may be arranged in the diverse location of community, path transmission time delay and multidiameter delay different, the time that the upward signal that each UE sends arrives base station receiving terminal is but consistent, so each UE completes the foundation of up initial synchronisation.

After up initial synchronisation is set up, along with the movement of each UE or the change of communication environments, distance between each UE and base station changes, propagation path changes, propagation delay time and multidiameter delay also change thereupon, base station need the uplink synchronous of each UE is safeguarded, be convenient to each UE follow-up carry out transmitting uplink data and control information transmission synchronous.The PUSCH (Physical Uplink Shared Channel) that base station sends according to UE and PUCCH (Physical Uplink Control Channel) data, new uplink timing advance is recalculated on the basis of initial timing lead, adjusts and upgrade the Timing Advance of each UE.

For the up PUSCH transfer of data of UE, DM RS symbol occupies some fixing OFDM symbol position in time slot, as shown in Figure 2, the accurate location of single DM RS symbol in each ascending time slot depend on be the use of standard C P (Normal CP) or expansion CP (Extended CP) type.For the conventional CP type that each time slot has 7 OFDM symbol, it is symbol 4 that DM RS symbol is plied in the centre; For the expansion CP type that each time slot has 6 OFDM symbol, DM RS symbol uses symbol 3.

For the up PUCCH control information transmission of UE, PUCCH format 1/1a/1b is used for terminal and sends " scheduling request information " or " the ACK/NACK information of 1bit, 2bit ".A modulation symbol d (0) is used to represent the information that PUCCH 1/1a/1b sends.For " scheduling request information " of PUCCH 1, d (0) is now set to predefined fixed value (d (0)=1).For the ACK information of PUCCH 1a/1b, d (0) is BPSK or QPSK modulation symbol, corresponds respectively to the situation of 1bit or 2bit ACK information.In the process of transmitting of information, orthogonal spreading sequence w (m) is first used to carry out spread spectrum, by information dispersion multiple uplink symbol for PUCCH transmission in a time slot; Then, each uplink symbol use 1 length to be the Zadoff-Chu sequence of 12 modulate, obtain the sequence of complex numbers that length is 12, corresponding to 12 subcarriers in 1 RB.Therefore, the transmission of PUCCH 1/1a/1b contains " orthogonal spreading sequence " and " Zadoff-Chu sequence " two process of subcategory number spread spectrum, as shown in Figure 3, is DM RS symbol and the data symbol positions schematic diagram of UE up transmission PUCCH format 1/1a/1b.

PUCCH format 2, for terminal transmitting channel state information (CSI), comprises channel quality information (CQI), precoding vector information (PMI) or Rank Indicator (RI).When Normal CP, also support to be extended to PUCCH format 2a/2b, in these two kinds of forms, by carrying out BPSK or QPSK modulation to the DM RS symbol in PUCCH format 2, on the basis of CSI information, the ACK/NACK information of further carrying 1bit or 2bit, this ACK information is by forming a modulation symbol d (10) after modulation.CSI information forms the data flow that length is 20bit after chnnel coding, formed after scrambling and QPSK modulation 10 modulation symbols (d (0) ..., d (9)), PUCCH format 2/2a/2b sends.Process of transmitting and the PUCCH format 1/1a/1b of PUCCH format 2/2a/2b information are similar, for no other reason than that will send more information, so without the operation of spread spectrum.For the modulation symbol information d (0) that will send ..., d (9), uses length to be the Zadoff-Chu sequence of 12 on every symbol modulate, then the result of each symbol-modulated is mapped on 12 subcarriers in subframe in corresponding uplink symbol 1 RB.Be that the different cyclic shifts of the Zadoff-Chu sequence of 12 carry out the multiplexing of different PUCCH 2/2a/2b channel in same RB by length.As shown in Figure 4, be DM RS symbol and the data symbol positions schematic diagram of UE up transmission PUCCH format 2/2a/2b.

Can find out, the calculating of uplink timing advance adjusted value is carried out by the signal extracted from the PUSCH/PUCCH that UE sends in base station, and obtained uplink timing advance adjusted value is used for the Timing Advance upgrading UE uplink, can safeguard and keep each UE uplink synchronous, the performance of elevator system.

At present, the computational methods of the existing uplink timing advance adjusted value for PUSCH and PUCCH mainly contain time domain matching method and the time domain channel estimation technique two class, and all only use the demodulated reference signal in PUSCH and PUCCH.

For time domain matching method, the DM RS symbol copy mainly generated this locality is changed by inverse discrete Fourier transform and is transformed into time domain, near DM RS symbol, carry out slip relevant to the PUSCH/PUCCH signal received, and finds correlation peak and then ask for uplink timing advance adjusted value.

For the time domain channel estimation technique, mainly utilize the DM RS symbol of the PUSCH/PUCCH signal received as channel estimation sequence, in uplink channel estimation window, according to obtained time domain channel estimated result, find peak-peak and then ask for uplink timing advance adjusted value.

In such scheme, owing to being all calculate at a data field, and be all only use DM RS symbol to ask for uplink timing advance adjusted value, cause required uplink timing advance adjusted value limited precision, accuracy is low.

Summary of the invention

In order to solve the problem, the invention provides the method for adjustment uplink timing advance, device and base station system, improve the precision calculating uplink timing advance adjusted value.

Adjust a method for uplink timing advance, comprise the following steps:

The symbol estimated for domain channel response is chosen from PUSCH/PUCCH;

Calculate the domain channel response estimated value of described symbol, and be converted into time domain channel response estimated value;

The power spectrum of described time domain channel response estimated value is carried out incoherent merging, chooses the point of the time-domain sampling corresponding to the peak-peak position of the merging power spectrum that incoherent merging obtains;

Calculate the side-play amount between described time-domain sampling point position and the target location of described symbol sebolic addressing, according to this side-play amount adjustment uplink timing advance.

Compared with prior art, the method of adjustment uplink timing advance of the present invention have employed frequency domain and time domain combined computational methods, picks symbols sequence from PUSCH/PUCCH, channel response estimation is carried out at frequency domain, obtain estimated value more accurately, then the power estimated by channel response in time domain carries out incoherent merging, determine the peak-peak of incoherent merging power, obtain the main path position of time domain channel response, calculate uplink timing advance adjusted value again, incoherent merging is carried out by the power estimated channel response, the power spectrum of more time domain channel response estimated sequence can be obtained, thus the main path position of time domain channel response more accurately can be obtained, and then calculate the higher uplink timing advance adjusted value of precision, improve the precision calculating uplink timing advance adjusted value.

Adjust a device for uplink timing advance, comprising:

Extraction unit, for choosing the symbol estimated for domain channel response from PUSCH/PUCCH;

Channel estimating unit, for calculating the domain channel response estimated value of described symbol, and is converted into time domain channel response estimated value;

Power merge cells, for the power spectrum of described time domain channel response estimated value is carried out incoherent merging, chooses the point of the time-domain sampling corresponding to the peak-peak position of the merging power spectrum that incoherent merging obtains;

Adjustment unit, for calculating the side-play amount between described time-domain sampling point position and the target location of described symbol sebolic addressing, according to this side-play amount adjustment uplink timing advance.

Compared with prior art, the device of adjustment uplink timing advance of the present invention have employed frequency domain and time domain combined technology, extraction unit is picks symbols from PUSCH/PUCCH, channel estimating unit carries out channel response estimation at frequency domain, obtain estimated value more accurately, power merge cells carries out incoherent merging in time domain to the power that channel response is estimated, determine the peak-peak of incoherent merging power, obtain the main path position of time domain channel response, adjustment unit calculates uplink timing advance adjusted value according to this main path position, by the incoherent merging of power estimated channel response, the power spectrum of more time-domain response estimated sequence can be obtained, thus the main path position of time domain channel response more accurately can be obtained, and then calculate the higher uplink timing advance adjusted value of precision, improve the precision calculating uplink timing advance adjusted value.

A kind of base station system, comprises the device of adjustment uplink timing advance described above.

Compared with prior art, base station system of the present invention, by the device of above-mentioned adjustment uplink timing advance, can calculate the uplink timing advance adjusted value that precision is higher, improves the precision calculating uplink timing advance adjusted value.

Accompanying drawing explanation

Fig. 1 is that base station calculates and adjusts the schematic flow sheet of UE uplink timing advance;

Fig. 2 is the demodulated reference signal position view of UE up transmission PUSCH;

Fig. 3 is demodulated reference signal and the data symbol positions schematic diagram of UE up transmission PUCCH format 1/1a/1b;

Fig. 4 is demodulated reference signal and the data symbol positions schematic diagram of UE up transmission PUCCH format 2/2a/2b;

Fig. 5 is the schematic flow sheet that the present invention adjusts the method for uplink timing advance;

Fig. 6 is the schematic flow sheet according to frequency domain symbol retrieval time domain channel response estimated sequence in embodiment;

Fig. 7 is the flow chart of the incoherent merging process in embodiment;

Fig. 8 is the apparatus structure schematic diagram that the present invention adjusts uplink timing advance;

Fig. 9 is the structural representation of the device of adjustment uplink timing advance in embodiment.

Embodiment

Technology of the present invention carries out up timing measuring and adjustation accurately to PUSCH and PUCCH of the up each UE of LTE, for obtaining new uplink timing advance adjusted value in PUSCH and PUCCH sent from UE, be the description carried out for conventional CP type, do not relate to the process obtaining initial timing lead from PRACH.

Be described in detail below in conjunction with the method for drawings and Examples to adjustment uplink timing advance of the present invention.

As shown in Figure 5, the method for adjustment uplink timing advance of the present invention, comprises the following steps:

The symbol estimated for domain channel response is chosen from PUSCH/PUCCH;

Calculate the domain channel response estimated value of described symbol, be then converted into time domain channel response estimated sequence;

The power spectrum of described time domain channel response estimated sequence is carried out incoherent merging, chooses the point of the time-domain sampling corresponding to the peak-peak position of the merging power spectrum that incoherent merging obtains;

Calculate the side-play amount between described time-domain sampling point position and the target location of described symbol sebolic addressing, according to this side-play amount adjustment uplink timing advance.

For the domain channel response estimated value of the described symbol of described calculating, and be converted into the process of time domain channel response estimated sequence, as shown in Figure 6, specifically comprise:

First described symbol is carried out discrete Fourier transform and convert frequency domain symbol sequence to, then it is carried out conjugate multiplication with the local burst copy being used for channel estimation in frequency domain and obtain domain channel response estimated sequence, again frequency domain zero padding operation is carried out to described domain channel response estimated sequence, and carry out inverse discrete Fourier transform and change and convert time domain channel response estimated sequence to.

For described frequency domain zero padding operation, comprise other frequency domain position zero paddings beyond bilateral zero padding, high frequency zero padding or channel resource allocation.

Wherein, namely described bilateral zero padding carries out zero padding in the end positions of the frequency domain resource corresponding to described domain channel response estimated sequence; Described bilateral zero padding, namely carries out zero padding on the high frequency position of the frequency domain resource corresponding to described domain channel response estimated sequence; Other frequency domain position zero paddings beyond described channel resource allocation, namely give on the residue frequency domain position beyond the frequency domain resource corresponding to the corresponding estimated sequence of described frequency domain channel system assignment and carry out zero padding.

For the process of described incoherent merging, as shown in Figure 7, particularly, first the power sequence of described time domain channel response estimated sequence is calculated, then correspondence summation is carried out to the power sequence described in the time slot of each described PUSCH/PUCCH, then the power sequence described in the antenna of the described PUSCH/PUCCH of all receptions is sued for peace.

In LTE system, demodulated reference signal (DM RS symbol) in the PUSCH that base station can utilize UE to send carries out the calculating of uplink timing advance adjusted value, and for UE send be PUCCH time, except can utilizing demodulated reference signal (DM RS symbol), the data symbol of PUCCH can also be utilized, or utilize DM RS symbol to carry out the calculating of uplink timing advance adjusted value together with data symbol.

As an embodiment, for the described symbol estimated for domain channel response chosen, if targeted customer sends is PUSCH, then choose the DM RS symbol of two time slots in a subframe; If that targeted customer sends is PUCCH, then choose DM RS symbol and/or the data symbol of two time slots in a subframe.

That send as targeted customer is PUSCH, and when choosing the DM RS symbol of two time slots in a subframe:

Described conjugate multiplication step comprises: by the frequency domain symbol sequence of described two DM RS symbols, carries out with the permanent envelope zero autocorrelation sequence copy corresponding to local targeted customer the domain channel response estimated value that conjugate multiplication obtains the signal in symbol.

The process of described incoherent merging comprises: the power sequence of the described time domain channel response estimated sequence that the time-domain symbol of calculating two DM RS symbols is corresponding first respectively, then the carrying out of the described power sequence of two time slots is sued for peace, then the power sequence of all antennas two time slots is sued for peace.

That send as targeted customer is PUCCH, and when choosing DM RS symbol and/or the data symbol of two time slots in a subframe:

Described conjugate multiplication step comprises: by the frequency domain symbol sequence of described data symbol, conjugate multiplication is carried out with to be multiplied with the permanent envelope zero autocorrelation sequence sequence copy of gained of the orthogonal intersection corresponding to local targeted customer, and by the frequency domain symbol sequence of described two DM RS symbols, obtain the domain channel response estimated value of the signal in symbol with to be multiplied with the permanent envelope zero autocorrelation sequence sequence copy conjugate multiplication of gained of the orthogonal intersection corresponding to local targeted customer.

The process of described incoherent merging comprises: the power sequence of the described time domain channel response estimated sequence that the time-domain symbol of calculating two DM RS symbols and/or data symbol is corresponding first respectively, then the carrying out of the described power sequence of two time slots is sued for peace, then the power sequence of all antennas two time slots is sued for peace.

For the method for incoherent merging, count summation or weighted linear summation can be adopted.

The time-domain sampling point position that the time-domain sampling point position once chosen can also be utilized after choosing the point of the time-domain sampling corresponding to peak-peak position to choose this is smoothing, obtains position more accurately.

In order to more clear method of the present invention, do more detailed elaboration below in conjunction with accompanying drawing and application example.

Example one: receive the PUSCH that targeted customer sends for base station, as Suo Shi (a) in Fig. 2 under Normal CP type, symbol 4 position choosing two time slots in PUSCH subframe calculates for each DM RS symbol, specifically comprises the following steps:

S101, choose from PUSCH for domain channel response estimate symbol; Preferably, base station is according to the PUSCH information receiving targeted customer, prefix information attached before each OFDM symbol in a subframe is removed with CP length, each symbol inclined when obtaining comprising, choose two each DM RS symbols of time slot (totally two DM RS symbols) in a subframe, namely choose two DM RS symbols on two time slot internal symbol 3 positions.

Particularly, after channel, the Received signal strength of the DM RS symbol of targeted customer can be expressed as:

$r(\mathrm{slot},\mathrm{ant},n_{\mathrm{user}})=h(\mathrm{slot},\mathrm{ant},n_{\mathrm{user}})\⊗s(\mathrm{slot},n_{\mathrm{user}})+n(\mathrm{slot},\mathrm{ant},n_{\mathrm{user}})$

Wherein, slot, ant, n _userthe respectively index of corresponding time slot, reception antenna and user, n be appointed as in the index of targeted customer _user, r, h, s and n wherein represent Received signal strength, time domain channel response, transmission signal and noise respectively, send signal s and are expressed as:

s(slot,n _user)＝w _ZC(slot,n _user)

Wherein, w _zCrepresent the time domain sequences of permanent envelope zero autocorrelation sequence.

S102, calculating domain channel response estimated value; Preferably, the signal in two DM RS symbols is utilized to be transformed into frequency domain by discrete Fourier transform respectively, choose the subcarrier sequence of targeted customer in corresponding frequency domain resource, with the permanent envelope zero autocorrelation sequence copy conjugate multiplication corresponding to local targeted customer;

Particularly, the Received signal strength being transformed into the DM RS symbol of frequency domain by discrete Fourier transform can be expressed as:

R(slot,ant,k,n _user)＝H(slot,ant,k,n _user)·S(slot,k,n _user)+N(slot,ant,k,n _user)

Wherein, k represents the index of the frequency domain resource allocation of subcarriers of targeted customer, and R, H, S and N represent Received signal strength, domain channel response, transmission signal and noise in corresponding frequency domain resource allocation of subcarriers respectively; The permanent envelope zero autocorrelation sequence copy of described transmission signal corresponding to local targeted customer, its formula is expressed as:

$S(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})=W_{\mathrm{ZC}}(\mathrm{slot},k,n_{\mathrm{user}})=r_{u,v}^{\left(\mathrm{\α}\right)}\left(k\right)$

Wherein, α is by n _userdetermine with slot.

After conjugate multiplication, the formula of the domain channel response estimated value of targeted customer can be expressed as:

$\begin{array}{c}\hat{H}(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})=\frac{R(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})}{W_{\mathrm{ZC}}(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})}\\ =H(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})+\frac{N(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})}{W_{\mathrm{ZC}}(\mathrm{slot},k,n_{\mathrm{user}})}\end{array}$

The frequency domain representation of the domain channel response estimated sequence of the targeted customer of gained is:

${\hat{H}}^{\mathrm{ant},\mathrm{slot}}\left(k\right),k=\mathrm{0,1},...,M-1,\mathrm{ant}\∈\left[\mathrm{1,4}\right],\mathrm{slot}\∈\left[\mathrm{1,2}\right],$

The wherein number of sub carrier wave of M shared by the distribution of targeted customer's frequency domain resource, ant is antenna serial number, and slot is slot index.

S103, convert domain channel response estimated sequence to time domain channel response estimated sequence; Preferably, first, respectively the domain channel response estimated sequence of being tried to achieve by two DM RS symbols is carried out frequency domain zero padding and operate, and then be converted to time domain by discrete inversefouriertransform and obtain time domain channel response estimated sequence.

For zero padding operation, particularly, comprise other frequency domain position zero paddings beyond bilateral zero padding, high frequency zero padding or channel resource allocation; According to bilateral zero padding, the end positions by the frequency domain resource corresponding to domain channel response estimated sequence carries out zero padding; According to high frequency zero padding, zero padding is carried out in the high frequency position by the frequency domain resource corresponding to domain channel response estimated sequence; According to other frequency domain position zero paddings beyond channel resource allocation, namely system assignment is given on the residue frequency domain position beyond the frequency domain resource corresponding to the corresponding estimated sequence of described frequency domain channel and carry out zero padding.

Particularly, each time slot every root antenna of base station system received the zero padding carrying out frequency domain is operated to N point (N is that the current corresponding FFT of LTE system sample rate counts), can obtain sequence through zero padding operation:

${\hat{H}}^{\mathrm{ant},\mathrm{slot}}\left(k\right),k=\mathrm{0,1},...,N-1,$

Then this sequence is obtained after N point IFFT the time domain channel response estimated sequence of channel, its formula is expressed as:

${\hat{h}}^{\mathrm{ant},\mathrm{slot}}\left(n\right)={\mathrm{IFFT}}_N\left\{{\hat{H}}^{\mathrm{ant},\mathrm{slot}}\left(k\right)\right\},k,n=\mathrm{0,1},...,N-1$

S104, the power spectrum of time domain channel response estimated sequence is carried out incoherent merging, namely incoherent merging is carried out to the power spectrum of the time domain channel response estimated sequence on each reception antenna, in two time slots; Preferably, first the sampled point performance number of time domain channel response estimated sequence corresponding to all DM RS symbols is calculated respectively, then by the summation of the sampled point performance number of time domain channel response estimated sequence corresponding for two DM RS symbols in two of each reception antenna time slots correspondence, then the power of all reception antennas is carried out correspondence summation.

Particularly, for the base station that multiple antennas receives, first calculate the performance number of time domain channel response estimated sequence each point respectively, obtain the power value sequence of the time domain channel response estimated sequence of the DM RS symbol of each time slot on each antenna and then the summation of above-mentioned power sequence correspondence is obtained to the performance number of each antenna, finally carry out correspondence summation to the power value sequence of each antenna and obtain incoherent merging performance number, computing formula can be expressed as:

${\left|\stackrel{\‾}{h}\left(n\right)\right|}^2=\left[\underset{\mathrm{ant}=1}{\overset{\mathrm{Nr}}{\mathrm{\Σ}}}\underset{\mathrm{slot}=1}{\overset{2}{\mathrm{\Σ}}}{\left|{\hat{h}}^{\mathrm{ant},\mathrm{slot}}\left(n\right)\right|}^2\right]$

Wherein, for incoherent merging performance number, in addition, for the mode of incoherent merging, except above-mentioned is counted except summation, weighted linear summing mode can also be adopted.

S105, choose the point of the time-domain sampling corresponding to the peak-peak position of the power spectrum that incoherent merging obtains, this time-domain sampling point position is the main path position of time domain channel response.

Particularly, to the result of the incoherent merging power that step S104 obtains, at [0, N _cP] search peak-peak in interval, determine the sampling point position corresponding to this peak-peak, its formula is expressed as:

$j_{\mathrm{peak}}=\arg \underset{n\∈[1,N_{\mathrm{CP}}]}{\max }\left[\underset{\mathrm{ant}=1}{\overset{\mathrm{Nr}}{\mathrm{\Σ}}}\underset{\mathrm{slot}=1}{\overset{2}{\mathrm{\Σ}}}{\left|{\hat{h}}^{\mathrm{ant},\mathrm{slot}}\left(n\right)\right|}^2\right]=\arg \underset{n\∈[1,N_{\mathrm{CP}}]}{\max }{\left|\stackrel{\‾}{h}\left(n\right)\right|}^2$

Wherein, Nr represents reception antenna number, N _cPrepresent CP length, in above formula, first incoherent merging be summed to the channel estimation sequence that different antennae obtains, second incoherent merging being summed to the channel estimation sequence to two time slots, j _peakbe main path position.

Preferably, after determining main path position, last main path position record value also can be utilized smoothing to the new main path position value produced; Make the main path position of trying to achieve more accurate.

S106, calculate time-domain sampling point position and each symbol itself target location before side-play amount, adjust uplink timing advance according to this side-play amount.

Particularly, according to the main path position j that step S105 tries to achieve _peak, be designated as up time offset estimation value ε _tA, the target location T of itself and each symbol itself _tAbetween side-play amount be uplink timing advance adjusted value Δ _tA, then according to this side-play amount (Δ _tA) adjustment uplink timing advance.

Example two: receive the PUCCH format 1/1a/1b that targeted customer sends for base station, as shown in Figure 3 under Normal CP type, it symbol 3,4,5 position choosing two time slots in PUCCH format 1/1a/1b subframe is DM RS symbol, for data symbol calculates on symbol 1,2,6,7 position, specifically comprise the following steps:

S201, choose from PUCCH for domain channel response estimate symbol; Preferably, two each 7 symbols of time slot comprise DM RS symbol and data symbol (totally 14 symbols);

Base station receives the PUCCH information of targeted customer, prefix information attached before each OFDM symbol in a subframe is removed with CP length, each symbol inclined when obtaining comprising, choose whole 14 symbols of two time slots (comprising data symbol sequence and DM RS symbol) in a subframe, namely choose the DM RS symbol on symbol 3,4,5 position in two time slots and the data symbol on symbol 1,2,6,7 position.

Particularly, for PUCCH format 1/1a/1b, because system allows the multiplexing identical running time-frequency resource of multiple user, the formula of the Received signal strength of symbol sebolic addressing after channel is expressed as:

$\begin{array}{c}r(\mathrm{slor},\mathrm{ant},\mathrm{symbol},n_{\mathrm{user}})=h(\mathrm{slot},\mathrm{ant},\mathrm{symbol},0)\⊗s(\mathrm{slot},\mathrm{symbol},0)\\ +\underset{n_{\mathrm{user}}=1}{\overset{N_{\mathrm{user}}-1}{\mathrm{\Σ}}}h(\mathrm{slot},\mathrm{ant},\mathrm{symbol},n_{\mathrm{suer}})\⊗s(\mathrm{slot},\mathrm{symbol},n_{\mathrm{user}})\\ +n(\mathrm{slot},\mathrm{ant},n_{\mathrm{user}})\end{array}$

Wherein, slot, ant, symbol, n _userthe respectively index of corresponding time slot, reception antenna, character position and user, the index of targeted customer is 0, and the index with other users multiplexing on running time-frequency resource is 1 ..., N _user-1; R, h, s and n represent Received signal strength, time domain channel response, transmission signal and noise respectively.

S202, calculating domain channel response estimated value; Preferably, respectively 14 symbols whole in two time slots are transformed into frequency domain by discrete Fourier transform, then calculate the domain channel response estimated value of each symbol respectively.

Particularly, respectively 14 symbols whole in two time slots are transformed into frequency domain by discrete Fourier transform, choose the subcarrier sequence of targeted customer in corresponding frequency domain resource, be multiplied sequence corresponding for data symbol and the orthogonal intersection corresponding to local targeted customer with permanent envelope zero autocorrelation sequence the sequence copy conjugate multiplication of gained, the sequence copy conjugate multiplication of the gained that sequence corresponding for DM RS symbol and the orthogonal intersection corresponding to local targeted customer is multiplied with permanent envelope zero autocorrelation sequence.

Be transformed into the Received signal strength of the symbol sebolic addressing of frequency domain by discrete Fourier transform, its formula can be expressed as:

$\begin{array}{c}R(\mathrm{slot},\mathrm{ant},k,\mathrm{symbol},n_{\mathrm{user}})=H(\mathrm{slot},\mathrm{ant},k,\mathrm{symbol},0)\·S(\mathrm{slot},k,\mathrm{symbol},0)\\ +\underset{n_{\mathrm{user}}=1}{\overset{N_{\mathrm{user}}-1}{\mathrm{\Σ}}}H(\mathrm{slot},\mathrm{ant},k,\mathrm{symbol},n_{\mathrm{user}})\·S(\mathrm{slot},k,\mathrm{symbol},n_{\mathrm{user}})\\ +N(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})\end{array}$

Wherein, k represents the index of the frequency domain resource allocation of subcarriers of targeted customer, and R, H, S and N represent Received signal strength, domain channel response, transmission signal and noise in corresponding frequency domain resource allocation of subcarriers respectively.

The orthogonal intersection of transmission signal corresponding to local targeted customer of DM RS symbol is multiplied with permanent envelope zero autocorrelation sequence the sequence copy of gained.

The sequence copy of gained and the modulation symbol of the transmission signal of data symbol corresponding to local targeted customer is multiplied with orthogonal intersection and permanent envelope zero autocorrelation sequence, its formula is expressed as:

Wherein, the orthogonal intersection of DM RS symbol can adopt different spread spectrum code characters from the orthogonal intersection of data symbol, and DM RS symbol and data symbol can adopt permanent envelope zero autocorrelation sequence of different displacement.

The domain channel response estimated sequence frequency domain representation of the targeted customer of gained is:

$\begin{array}{c}\hat{H}(\mathrm{slot},\mathrm{ant},k,\mathrm{symbol},0)=\frac{R(\mathrm{slot},\mathrm{ant},k,\mathrm{symbol},n_{\mathrm{user}})}{W_{\mathrm{ZC}}(\mathrm{slot},k,\mathrm{symbol},0)\·W_{\mathrm{OC}}(\mathrm{slot},k,\mathrm{symbol},0)}\\ =\left\{\begin{array}{cc}{\hat{H}}_{\mathrm{RS}}(\mathrm{slot},\mathrm{a\; nt},k,\mathrm{symbol},0)& ,\mathrm{sy\; mbol}=\mathrm{3,4,5}\\ {\hat{H}}_{\mathrm{d\; ata}}(\mathrm{slot},\mathrm{an\; t},k,\mathrm{symbol},0)& ,\mathrm{symbol}=\mathrm{1,2,6,7}\end{array}\right.\\ =\left\{\begin{array}{cc}{H}_{\mathrm{RS}}(\mathrm{slot},\mathrm{ant},k,\mathrm{s\; ymbol},0)+X& ,\mathrm{symbol}=\mathrm{3,4,5}\\ {\mathrm{\η}}_{\mathrm{CI}}\left(0\right)\·H_{\mathrm{data}}(\mathrm{slot},\mathrm{ant},k,\mathrm{symbo\; l},0)+X& ,\mathrm{symbol}=\mathrm{1,2,6,7}\end{array}\right.\end{array}$

$X=\frac{\underset{n_{\mathrm{user}}=1}{\overset{N_{\mathrm{user}}-1}{\mathrm{\Σ}}}H(\mathrm{slot},\mathrm{ant},k,\mathrm{symbol},n_{\mathrm{user}})\·S(\mathrm{slot},k,\mathrm{symbol},n_{\mathrm{user}})+N(\mathrm{slot},\mathrm{ant},k,n_{\mathrm{user}})}{W_{\mathrm{ZC}}(\mathrm{slot},k,\mathrm{symbol},0)\·W_{\mathrm{OC}}(\mathrm{slot},k,\mathrm{symbol},0)}$

The domain channel response estimated sequence frequency domain representation of the targeted customer obtained is:

${\hat{H}}^{\mathrm{ant},\mathrm{slot},\mathrm{symbol}}\left(k\right),k=\mathrm{0,1},...,M-1,\mathrm{ant}\∈\left[\mathrm{1,4}\right],\mathrm{slot}\∈\left[\mathrm{1,2}\right],\mathrm{symbol}\∈\left[\mathrm{1,7}\right],$

Wherein, the number of sub carrier wave of M shared by the distribution of targeted customer's frequency domain resource, ant is antenna serial number, and slot is slot index, and symbol is the symbol sequence number in time slot.

S203, convert domain channel response estimated sequence to time domain channel response estimated sequence; Preferably, first, respectively the domain channel response estimated sequence of being tried to achieve by two DM RS symbols and data symbol is carried out frequency domain zero padding and operate, and then be converted to time domain by discrete inversefouriertransform and obtain time domain channel response estimated sequence.

For zero padding operation, particularly, comprise other frequency domain position zero paddings beyond bilateral zero padding, high frequency zero padding or channel resource allocation; According to bilateral zero padding, the end positions by the frequency domain resource corresponding to domain channel response estimated sequence carries out zero padding; According to high frequency zero padding, zero padding is carried out in the high frequency position by the frequency domain resource corresponding to domain channel response estimated sequence; According to other frequency domain position zero paddings beyond channel resource allocation, namely system assignment is given on the residue frequency domain position beyond the frequency domain resource corresponding to the corresponding estimated sequence of described frequency domain channel and carry out zero padding.

Particularly, each time slot every root antenna of base station system received the zero padding carrying out frequency domain is operated to N point (N is that the current corresponding FFT of LTE system sample rate counts), can obtain sequence through zero padding operation then this sequence is obtained after N point IFFT the time domain channel response estimated sequence of channel, its formula is expressed as:

${\hat{h}}^{\mathrm{ant},\mathrm{slot},\mathrm{symbol}}\left(n\right)={\mathrm{IFFT}}_N\left\{{\hat{H}}^{\mathrm{ant},\mathrm{slot},\mathrm{symbol}}\left(k\right)\right\},k,n=\mathrm{0,1},...,N-1$

S204, the power spectrum of all time domain channel response estimated sequences is carried out incoherent merging, namely incoherent merging is carried out to the power spectrum of the time domain channel response estimated sequence on each reception antenna, in two time slots; Preferably, first the sampled point performance number of time domain channel response estimated sequence corresponding to all DM RS symbols is calculated respectively, then by the sampled point performance number correspondence summation of two DM RS symbols in two of each reception antenna time slots and time domain channel response estimated sequence corresponding to data symbol, then the power of all reception antennas is carried out correspondence and sue for peace.

Particularly, for the base station that multiple antennas receives, first calculate the performance number of time domain channel response estimated sequence each point respectively, obtain the power sequence of the time domain channel response estimated sequence of each 7 symbols (comprising DM RS symbol and data symbol) on each antenna and then the summation of above-mentioned power sequence correspondence is obtained to the performance number of each antenna, finally carry out correspondence summation to the power value sequence of each antenna and obtain incoherent merging performance number, the formula of calculating can be expressed as:

${\left|\stackrel{\‾}{h}\left(n\right)\right|}^2=\left[\underset{\mathrm{ant}=1}{\overset{\mathrm{Nr}}{\mathrm{\Σ}}}\underset{\mathrm{slot}=1}{\overset{2}{\mathrm{\Σ}}}\underset{\mathrm{symbol}=1}{\overset{7}{\mathrm{\Σ}}}{\left|{\hat{h}}^{\mathrm{ant},\mathrm{slot},\mathrm{symbol}}\left(n\right)\right|}^2\right]$

Wherein, for incoherent merging performance number, in addition, for the mode of incoherent merging, except above-mentioned is counted except summation, weighted linear summing mode can also be adopted.

S205, choose the point of the time-domain sampling corresponding to the peak-peak position of the power spectrum that incoherent merging obtains, this time-domain sampling point position is the main path position of time domain channel response.

Particularly, to the result of the incoherent merging power that step S104 obtains, at [0, N _cP] search peak-peak in interval, determine the sampling point position corresponding to this peak-peak, its formula is expressed as:

$j_{\mathrm{peak}}=\arg \underset{n\∈[1,N_{\mathrm{CP}}]}{\max }\left[\underset{\mathrm{ant}=1}{\overset{\mathrm{Nr}}{\mathrm{\Σ}}}\underset{\mathrm{slot}=1}{\overset{2}{\mathrm{\Σ}}}\underset{\mathrm{symbol}=1}{\overset{7}{\mathrm{\Σ}}}{\left|{\hat{h}}^{\mathrm{ant},\mathrm{slot},\mathrm{symbol}}\left(n\right)\right|}^2\right]=\arg \underset{n\∈[1,N_{\mathrm{CP}}]}{\max }{\left|\stackrel{\‾}{h}\left(n\right)\right|}^2$

Wherein Nr represents reception antenna number, N _cPrepresent CP length.In above formula, first incoherent merging be summed to the channel estimation sequence that different antennae obtains, second incoherent merging being summed to the channel estimation sequence to two time slots, the 3rd the incoherent merging being summed to the channel estimation sequence in time slot on 7 symbols, j _peakbe main path position.

Preferably, after determining main path position, last main path position record value also can be utilized smoothing to the new main path position value produced; Make the main path position of trying to achieve more accurate.

S206, calculate time-domain sampling point position and each symbol itself target location before side-play amount, adjust uplink timing advance according to this side-play amount.

Particularly, according to the main path position j that step S205 tries to achieve _peak, be designated as up time offset estimation value ε _tA, the target location T of itself and each symbol itself _tAbetween side-play amount be uplink timing advance adjusted value Δ _tA, then according to this side-play amount (Δ _tA) adjustment uplink timing advance.

Be described in detail below in conjunction with the device of drawings and Examples to adjustment uplink timing advance of the present invention.

As shown in Figure 8, the device of adjustment uplink timing advance of the present invention, comprising:

Extraction unit, for choosing the symbol estimated for domain channel response from PUSCH/PUCCH;

Channel estimating unit, for calculating the domain channel response estimated value of described symbol, is then converted into time domain channel response estimated sequence;

Power merge cells, for the power spectrum of described time domain channel response estimated sequence is carried out incoherent merging, chooses the point of the time-domain sampling corresponding to the peak-peak position of the merging power spectrum that incoherent merging obtains;

Adjustment unit, for calculating the side-play amount between described time-domain sampling point position and the target location of described symbol sebolic addressing, according to this side-play amount adjustment uplink timing advance.

For the mode of incoherent merging, count summation or weighted linear summation can be adopted.

Further, the time-domain sampling point position that adjustment unit is also chosen this for the time-domain sampling point position utilizing the last time to choose is smoothing, obtains position more accurately.

For the described symbol estimated for domain channel response chosen, if targeted customer sends is PUSCH, then choose the DM RS symbol of two time slots in a subframe; If that targeted customer sends is PUCCH, then choose DM RS symbol and/or the data symbol of two time slots in a subframe.

In order to the device of more clear adjustment uplink timing advance of the present invention, do more detailed elaboration below in conjunction with drawings and Examples, as shown in Figure 9.

For channel estimating unit, preferably, comprising:

Fourier transform module, converts frequency domain symbol sequence to for described symbol is carried out discrete Fourier transform;

Conjugate multiplication module, obtains domain channel response estimated sequence for described frequency domain symbol sequence is carried out conjugate multiplication with the local burst copy being used for channel estimation in frequency domain;

Described frequency band zero padding module, for carrying out frequency domain zero padding operation to described domain channel response estimated sequence;

Described Fourier inversion module, carries out inverse discrete Fourier transform for the domain channel response estimated sequence after zero padding being operated and changes and convert time domain channel response estimated sequence to.

For described frequency domain zero padding operation, comprise other frequency domain position zero paddings beyond bilateral zero padding, high frequency zero padding or channel resource allocation.

Wherein, namely described bilateral zero padding carries out zero padding in the end positions of the frequency domain resource corresponding to described domain channel response estimated sequence; Described bilateral zero padding, namely carries out zero padding on the high frequency position of the frequency domain resource corresponding to described domain channel response estimated sequence; Other frequency domain position zero paddings beyond described channel resource allocation, namely give on the residue frequency domain position beyond the frequency domain resource corresponding to the corresponding estimated sequence of described frequency domain channel system assignment and carry out zero padding.

For power merge cells, preferably, comprising:

Sequence power computing module, for calculating the power sequence of described time domain channel response estimated sequence;

Time slot power summation module, carries out correspondence summation for the power sequence described in the time slot to each described PUSCH/PUCCH;

Antenna power summation module, sues for peace for the power sequence described in the antenna to the described PUSCH/PUCCH of all receptions.

Other features in the present embodiment are same as the previously described embodiments, do not repeat them here.

Set forth the embodiment of base station system of the present invention below.

Base station system of the present invention, comprises the device of adjustment uplink timing advance described above.By the device of above-mentioned adjustment uplink timing advance, base station system of the present invention can calculate the higher uplink timing advance adjusted value of precision, improves the precision calculating uplink timing advance adjusted value.

Above-described embodiment of the present invention, does not form limiting the scope of the present invention.Any amendment done within the spirit and principles in the present invention, equivalent replacement and improvement etc., all should be included within claims of the present invention.

Claims (9)

1. adjust a method for uplink timing advance, it is characterized in that, comprise the following steps:

The symbol estimated for domain channel response is chosen from PUSCH/PUCCH; Specifically comprise: if targeted customer sends is PUSCH, described in the symbol estimated for domain channel response chosen comprise the DM RS symbol of two time slots in a subframe; If that targeted customer sends is PUCCH, described in the symbol estimated for domain channel response chosen comprise DM RS symbol and/or the data symbol of two time slots in a subframe;

Calculate the domain channel response estimated value of described symbol, and be converted into time domain channel response estimated sequence; Specifically comprise: first described symbol is carried out discrete Fourier transform and convert frequency domain symbol sequence to, then described frequency domain symbol sequence is carried out conjugate multiplication with the local burst copy being used for channel estimation in frequency domain and obtain domain channel response estimated sequence, frequency domain zero padding operation is carried out to described domain channel response estimated sequence, then the domain channel response estimated sequence after zero padding is carried out inverse discrete Fourier transform and change and convert time domain channel response estimated sequence to;

The power spectrum of described time domain channel response estimated sequence is carried out incoherent merging, chooses the point of the time-domain sampling corresponding to the peak-peak position of the merging power spectrum that incoherent merging obtains;

Calculate the side-play amount between described time-domain sampling point position and the target location of symbol sebolic addressing, according to this side-play amount adjustment uplink timing advance.

2. the method for adjustment uplink timing advance according to claim 1, it is characterized in that, the process of described incoherent merging comprises step: the power sequence first calculating described time domain channel response estimated sequence, then the power sequence of described time domain channel response estimated sequence corresponding to the symbol chosen of described two time slots of described PUSCH/PUCCH is sued for peace, obtain the performance number of each antenna, the more described performance number of each antenna receiving described PUSCH/PUCCH is sued for peace.

3. the method for adjustment uplink timing advance according to claim 2, is characterized in that, described to described domain channel response estimated sequence carry out frequency domain zero padding operation comprise:

Bilateral zero padding is carried out to described domain channel response estimated sequence, described domain channel response estimated sequence is carried out to high frequency zero padding or to the frequency domain position zero padding beyond frequency domain position shared by described domain channel response estimated sequence.

4. the method for adjustment uplink timing advance according to claim 3, is characterized in that, described conjugate multiplication comprises:

If that targeted customer sends is PUSCH, and when choosing the DM RS symbol of two time slots in a subframe, by the frequency domain symbol sequence of described DM RS symbol, carry out conjugate multiplication with the permanent envelope zero autocorrelation sequence copy corresponding to local targeted customer;

If that targeted customer sends is PUCCH, and when choosing DM RS symbol and/or the data symbol of two time slots in a subframe, by the frequency domain symbol sequence of described DM RS symbol, to be multiplied with permanent envelope zero autocorrelation sequence the sequence copy conjugate multiplication of gained with the orthogonal intersection corresponding to local targeted customer; And/or by the frequency domain symbol sequence of described data symbol, carry out conjugate multiplication with to be multiplied with the permanent envelope zero autocorrelation sequence sequence copy of gained of the orthogonal intersection corresponding to local targeted customer.

5. the method for adjustment uplink timing advance according to claim 2, is characterized in that, the process of described incoherent merging specifically comprises step:

If that targeted customer sends is PUSCH, first the power sequence of described time domain channel response estimated sequence corresponding to the described DM RS symbol of described two time slots is calculated, then the power sequence of described time domain channel response estimated sequence corresponding for the described DM RS symbol of described two time slots is sued for peace, obtain the performance number of each antenna, then the performance number of all antennas is sued for peace;

If that targeted customer sends is PUCCH, first the power sequence of the DM RS symbol of described two time slots and/or described time domain channel response estimated sequence corresponding to data symbol is calculated, then the power sequence of the DM RS symbol of described two time slots and/or described time domain channel response estimated sequence corresponding to data symbol is sued for peace, obtain the performance number of each antenna, then the performance number of all antennas is sued for peace.

6. method according to claim 1, it is characterized in that, also comprise behind the time-domain sampling point position corresponding to the described peak-peak choosing the merging power spectrum that incoherent merging obtains: the time-domain sampling point position utilizing the last time-domain sampling point position chosen to choose this is smoothing.

7. adjust a device for uplink timing advance, it is characterized in that, comprising:

Extraction unit, for choosing the symbol estimated for domain channel response from PUSCH/PUCCH; Specifically comprise: if targeted customer sends is PUSCH, described in the symbol estimated for domain channel response chosen comprise the DM RS symbol of two time slots in a subframe; If that targeted customer sends is PUCCH, described in the symbol estimated for domain channel response chosen comprise DM RS symbol and/or the data symbol of two time slots in a subframe;

Channel estimating unit, for calculating the domain channel response estimated value of described symbol, and is converted into time domain channel response estimated sequence; Wherein, described channel estimating unit comprises: Fourier transform module, converts frequency domain symbol sequence to for described symbol is carried out discrete Fourier transform; Conjugate multiplication module, obtains domain channel response estimated sequence for described frequency domain symbol sequence is carried out conjugate multiplication with the local burst copy being used for channel estimation in frequency domain; Frequency band zero padding module, for carrying out frequency domain zero padding to described domain channel response estimated sequence; Fourier inversion module, changes convert time domain channel response estimated sequence to for the domain channel response estimated sequence after zero padding being carried out inverse discrete Fourier transform;

Power merge cells, for the power spectrum of described time domain channel response estimated sequence is carried out incoherent merging, chooses the point of the time-domain sampling corresponding to the peak-peak position of the merging power spectrum that incoherent merging obtains;

Adjustment unit, for calculating the side-play amount between described time-domain sampling point position and the target location of symbol sebolic addressing, according to this side-play amount adjustment uplink timing advance.

8. the device of adjustment uplink timing advance according to claim 7, is characterized in that, described power merge cells comprises:

Sequence power computing module, for calculating the power sequence of described time domain channel response estimated sequence;

Time slot power summation module, the described power sequence of the described time domain channel response estimated sequence that the symbol chosen for described two time slots to described PUSCH/PUCCH is corresponding is sued for peace, and obtains the performance number of each antenna;

Antenna power summation module, for suing for peace to the described performance number of each antenna receiving described PUSCH/PUCCH.

9. a base station system, is characterized in that, comprising: the device of adjustment uplink timing advance as claimed in claim 7 or 8.