A kind of timing offset estimation method and device
Technical field
The present invention relates to field of communication technology more particularly to a kind of timing offset estimation methods, device and terminal.
Background technique
Inter-Cell Interference Coordination (Further Enhanced ICIC, the FeICIC) technology further enhanced needs to cope with
Occur under isomery scene adjacent area public reference signal (Cell-specific reference signals, CRS, also referred to as
The specific reference signal of cell) and/or Physical Broadcast Channel (Physical Broadcast Channel, PBCH) to this cell
Strong jamming, (also referred to as such as macro base station-femto base station (also referred to as macro-pico) deployment scenario or macro base station-home base station
Macro-femto) deployment scenario, therefore, terminal (UE) need to carry out interference elimination to CRS and/or PBCH.
Under normal circumstances, the time that interfered cell reaches the time of UE and this cell reaches UE exist it is certain relatively partially
Difference, there is also certain relative deviations for frequency deviation, and relative time delay deviation possible range is in [- 3,3] microsecond (us), relative frequency deviation
Deviation possible range is within [- 300,300] hertz (Hz).A fast Fourier is used only in time-frequency convert and becomes by general UE
(Fast Fourier Transformation, FFT) arithmetic element is changed, therefore in order to ensure the demodulation performance of local area, UE can only
Timing windowing position is arranged in reception signal based on this cell in the time domain, i.e., the timing that can not track adjacent area carries out adjacent area reality
When it is synchronous, carry out needing to estimate the delay spread of adjacent area after channel estimation according to local area timing receipt signal and to adjacent area to carry out
Frequency domain filtering.
By taking long term evolution (Long Term Evolution, LTE) downlink as an example, as shown in Figure 1, expanding existing time delay
Exhibition algorithm for estimating is described as follows: it is S that known descending pilot frequency, which sends sequence, and the signal received is Y, and spatial frequency domain channel is
H+n, wherein H indicates that the impulse response of wireless fading channel, n indicate white Gaussian noise, then meet Y=(H+n) S, thus
It can estimate channel estimation in frequency domain are as follows:Channel estimation in frequency domain is transformed to time domain progress delay spread to estimate
Meter, it is specific as follows: frequency domain channel to be transformed into time domain, according to cyclic prefix (Cyclic Prefix, CP) length or prior information
It determines the position of useful signal time delay maximum diameter, takes out the noise in time domain diameter and maximum diameter for being free of available signal power, calculate
Noise power PnoiseAnd peak power Pmax, effective diameter threshold value is determined by setting peak factor and noise factor, thus
Effective diameter search space is obtained, determines delay spread value.
Wherein, noise factor and peak factor can be configured based on experience value, and effective diameter threshold value indicates are as follows: and Γ=
(Pnoise·βnoise,Pmax·βmax), wherein βnoiseIt indicates noise gate, is the product of noise power and noise factor, βmaxTable
Show peak value threshold, is the product of peak power and peak factor.The method of noise window is set according to CP length are as follows: makees CP length
For the when elongatedness of time delay maximum diameter in system, the position of noise window is calculated.CP is defined in LTE system under different bandwidth
The T of protection interval CPSNumber is NCP, TSIndicate sampling time interval, FFT points are NFFT, sub-carrier number NSCIf pilot tone
FFT length when frequency domain accordingly transforms to time domain uses NSC/ 6, then the time-domain position of time delay maximum diameter can indicate are as follows:
In view of using inverse discrete Fourier transform (Inverse Discrete Fourier Transform, IDFT)
The power leakage of signal may be occurred for frequency-domain transform to time domain by transformation, can retain NFFTIn NleakDiameter, last is effective
The range of diameter is [NFFT-Nleak:N-1,0:Nτ], noise window is [Nτ:NFFT-Nleak]。
If adjacent area timing and local area there are it is larger in advance or lag, all may cause effective diameter exit window, i.e. noise window
In the search space inaccuracy comprising effective diameter and effective diameter, the calculating of effective diameter thresholding will be directly affected, and then influence adjacent
Area's Timing measurement.
Summary of the invention
The embodiment of the present invention provides estimation method, device and the terminal of a kind of timing offset, to solve in adjacent area timing
With local area there are it is larger in advance or lag, in the case where may cause effective diameter exit window, directly affect the meter of effective diameter thresholding
The problem of calculating, and then influencing adjacent area Timing measurement.
Specific technical solution provided in an embodiment of the present invention is as follows:
The embodiment of the present invention provides a kind of timing offset estimation method, comprising:
Channel estimation, which is carried out, according to the public reference signal CRS of the adjacent cell of current area determines time domain channel estimation knot
Fruit determines the first noise window power and peak power of the time domain channel estimated result;
The first effective diameter thresholding is determined according to the first noise window power and the peak power, according to the time domain
Channel estimation results and the first effective diameter thresholding determine the first timing offset value of current area Yu the adjacent cell;
It is adjusted according to timing offset of the first timing offset value to the time domain channel estimated result, determines and adjust
Second noise window power of the time domain channel estimated result after whole, according to the second noise window power and the peak power
Determine the second effective diameter thresholding;
According to the time domain channel estimated result adjusted and the second effective diameter thresholding, to tap search space
The the second timing offset value for scanning for determining current area and the adjacent cell, according to the first timing offset value and described
Second timing offset value determines the timing offset between current area and the adjacent cell.
In possible embodiment, the method also includes:
According to time domain channel estimated result, the second effective diameter thresholding and the timing offset adjusted,
Scan for determining the delay spread value of current area and the adjacent cell to tap search space.
In possible embodiment, it is true that channel estimation is carried out according to the public reference signal CRS of the adjacent cell of current area
Domain channel estimation results, comprising:
Least-squares estimation, which is carried out, according to the CRS of the adjacent cell obtains channel estimation in frequency domain as a result, believing the frequency domain
Road estimated result carries out inverse discrete Fourier transform, obtains the time domain channel estimated result.
In possible embodiment, the first noise window power and peak work of the time domain channel estimated result are determined
Rate, comprising:
Calculate the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, it indicates are as follows:Its
In,Indicate the time domain channel estimation of the column pilot tone of port p
As a result, r indicates receiving antenna number index, NFFTIndicate FFT points;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the first noise window power are as follows:Wherein, Nτ
Indicate the time-domain position of time delay maximum diameter, NleakIndicate the N retainedFFTDiameter item number;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the peak power are as follows:
In possible embodiment, the first effective diameter is determined according to the first noise window power and the peak power
Thresholding, comprising:
The product for calculating the first noise window power and the first coefficient obtains the first product, and calculates the peak work
Rate and the product of the second coefficient obtain the second product;
Select the maximum value in first product and second product, however, it is determined that the maximum value is greater than or equal to institute
Peak power is stated, determines that the first effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak value
Power determines that the first effective diameter thresholding is the maximum value.
In possible embodiment, according to the time domain channel estimated result and the first effective diameter thresholding, determine
First timing offset value of current area and the adjacent cell, comprising:
Determine the first timing offset value of current area Yu the adjacent cell are as follows:Wherein,P table
Show that total port number, R indicate receiving antenna sum, wherein Γ(r,p)Indicate the first effective diameter thresholding.
It is inclined according to timing of the first timing offset value to the time domain channel estimated result in possible embodiment
Difference is adjusted, comprising:
When the corresponding time-domain taps of first timing offset described in the time domain channel estimated result are moved to zero
Each time-domain taps in the time domain channel estimated result are successively translated, obtain time domain channel adjusted and estimate by domain tap
Count result are as follows:Wherein, k=0 ..., NFFT- 1, NFFT
Indicate FFT points, τ1It indicates the first timing offset value, indicates that the time domain channel of the column pilot tone of port p estimates knot
Fruit.
In possible embodiment, the second effective diameter is determined according to the second noise window power and the peak power
Thresholding, comprising:
The product for calculating the second noise window power and third coefficient obtains third product, and calculates the peak work
Rate and the product of the 4th coefficient obtain the 4th product;
Select the maximum value in the third product and the 4th product, however, it is determined that the maximum value is greater than or equal to institute
Peak power is stated, determines that the second effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak value
Power determines that the second effective diameter thresholding is the maximum value.
In possible embodiment, according to the time domain channel estimated result adjusted, the second effective diameter thresholding
And the timing offset, scan for determining the delay spread value of current area and the adjacent cell to tap search space,
Include:
According to the time domain channel estimated result adjusted, the second effective diameter thresholding, head path position is determined are as follows:I=-Nleak,…,
Nτ, NτIndicate that the time-domain position of time delay maximum diameter, r indicate receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates the call number of the pilot tone column of port p, indicates the second effective diameter thresholding, NleakIndicate the N retainedFFT's
The item number of diameter, (τ '1+τ1) indicate the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing partially
Difference;
Determine tail footpath position are as follows:
Wherein, i=-Nleak,…,Nτ, r expression receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates end
The call number of the pilot tone column of mouth p, indicates the second effective diameter thresholding, NleakIndicate the N retainedFFTDiameter item number,
(τ’1+τ1) indicate the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing offset;
Determine the tail footpath position subtract the first path position it is resulting as a result, by the result be determined as current area with
The delay spread value of the adjacent cell.
A kind of timing offset estimation device is additionally provided in the embodiment of the present invention, comprising:
First processing module, the public reference signal CRS progress channel estimation for the adjacent cell according to current area are true
Domain channel estimation results determine the first noise window power and peak power of the time domain channel estimated result;
Second processing module, for determining the first effective diameter according to the first noise window power and the peak power
Thresholding determines current area and the adjacent cell according to the time domain channel estimated result and the first effective diameter thresholding
The first timing offset value;
Third processing module, for inclined according to timing of the first timing offset value to the time domain channel estimated result
Difference is adjusted, and the second noise window power of time domain channel estimated result adjusted is determined, according to the second noise window function
Rate and the peak power determine the second effective diameter thresholding;
Fourth processing module, for according to the time domain channel estimated result adjusted and the second effective diameter door
Limit scans for determining the second timing offset value of current area and the adjacent cell to tap search space, according to described the
One timing deviation and the second timing offset value determine the timing offset between current area and the adjacent cell.
In possible embodiment, further includes the 5th processing module, is used for:
According to time domain channel estimated result, the second effective diameter thresholding and the timing offset adjusted,
Scan for determining the delay spread value of current area and the adjacent cell to tap search space.
In possible embodiment, the first processing module is specifically used for:
Least-squares estimation, which is carried out, according to the CRS of the adjacent cell obtains channel estimation in frequency domain as a result, believing the frequency domain
Road estimated result carries out inverse discrete Fourier transform, obtains the time domain channel estimated result.
In possible embodiment, the first processing module is specifically used for:
Calculate the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, it indicates are as follows:Its
In,Indicate the time domain channel estimation of the column pilot tone of port p
As a result, r indicates receiving antenna number index, NFFTIndicate FFT points;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the first noise window power are as follows:Wherein, Nτ
Indicate the time-domain position of time delay maximum diameter, NleakIndicate the N retainedFFTDiameter item number;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the peak power are as follows:
In possible embodiment, the Second processing module is specifically used for:
The product for calculating the first noise window power and the first coefficient obtains the first product, and calculates the peak work
Rate and the product of the second coefficient obtain the second product;
Select the maximum value in first product and second product, however, it is determined that the maximum value is greater than or equal to institute
Peak power is stated, determines that the first effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak value
Power determines that the first effective diameter thresholding is the maximum value.
In possible embodiment, the Second processing module is specifically used for:
Determine the first timing offset value of current area Yu the adjacent cell are as follows:Wherein,P table
Show that total port number, R indicate receiving antenna sum, wherein Γ(r,p)Indicate the first effective diameter thresholding.
In possible embodiment, the third processing module is specifically used for:
When the corresponding time-domain taps of first timing offset described in the time domain channel estimated result are moved to zero
Each time-domain taps in the time domain channel estimated result are successively translated, obtain time domain channel adjusted and estimate by domain tap
Count result are as follows:Wherein, k=0 ..., NFFT- 1, NFFT
Indicate FFT points, τ1It indicates the first timing offset value, indicates that the time domain channel of the column pilot tone of port p estimates knot
Fruit.
In possible embodiment, the third processing module is specifically used for:
The product for calculating the second noise window power and third coefficient obtains third product, and calculates the peak work
Rate and the product of the 4th coefficient obtain the 4th product;
Select the maximum value in the third product and the 4th product, however, it is determined that the maximum value is greater than or equal to institute
Peak power is stated, determines that the second effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak value
Power determines that the second effective diameter thresholding is the maximum value.
In possible embodiment, the 5th processing module is specifically used for:
According to the time domain channel estimated result adjusted, the second effective diameter thresholding, head path position is determined are as follows:I=-Nleak,…,
Nτ, NτIndicate that the time-domain position of time delay maximum diameter, r indicate receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates the call number of the pilot tone column of port p, indicates the second effective diameter thresholding, NleakIndicate the N retainedFFT's
The item number of diameter, (τ '1+τ1) indicate the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing partially
Difference;
Determine tail footpath position are as follows:Wherein, i=-
Nleak,…,Nτ, r expression receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates the pilot tone of port p
The call number of column indicates the second effective diameter thresholding, NleakIndicate the N retainedFFTDiameter item number, (τ '1+τ1) table
Show the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing offset;
Determine the tail footpath position subtract the first path position it is resulting as a result, by the result be determined as current area with
The delay spread value of the adjacent cell.
The embodiment of the invention also provides a kind of terminal, which mainly includes processor and memory, wherein memory
In preserve preset program, processor executes following procedure for reading the program saved in memory, according to the program:
Channel estimation, which is carried out, according to the public reference signal CRS of the adjacent cell of current area determines time domain channel estimation knot
Fruit determines the first noise window power and peak power of the time domain channel estimated result;
The first effective diameter thresholding is determined according to the first noise window power and the peak power, according to the time domain
Channel estimation results and the first effective diameter thresholding determine the first timing offset value of current area Yu the adjacent cell;
It is adjusted according to timing offset of the first timing offset value to the time domain channel estimated result, determines and adjust
Second noise window power of the time domain channel estimated result after whole, according to the second noise window power and the peak power
Determine the second effective diameter thresholding;
According to the time domain channel estimated result adjusted and the second effective diameter thresholding, to tap search space
The the second timing offset value for scanning for determining current area and the adjacent cell, according to the first timing offset value and described
Second timing offset value determines the timing offset between current area and the adjacent cell.
In possible embodiment, processor according to the time domain channel estimated result adjusted, described second effectively
Diameter thresholding and the timing offset scan for tap search space to determine that the time delay of current area and the adjacent cell expands
Exhibition value.
In possible embodiment, processor carries out least-squares estimation according to the CRS of the adjacent cell and obtains frequency domain letter
Road estimated result carries out inverse discrete Fourier transform to the channel estimation in frequency domain result, obtains the time domain channel estimation knot
Fruit.
In possible embodiment, processor determines the first noise window power and peak of the time domain channel estimated result
It is worth power, detailed process are as follows:
Calculate the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, it indicates are as follows:Its
In,Indicate the time domain channel estimation of the column pilot tone of port p
As a result, r indicates receiving antenna number index, NFFTIndicate FFT points;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the first noise window power are as follows:Wherein, Nτ
Indicate the time-domain position of time delay maximum diameter, NleakIndicate the N retainedFFTDiameter item number;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the peak power are as follows:
In possible embodiment, processor calculates the first noise window power and the product of the first coefficient obtains first
Product, and the calculating peak power and the product of the second coefficient obtain the second product;
Select the maximum value in first product and second product, however, it is determined that the maximum value is greater than or equal to the peak
It is worth power, determines that the first effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak power, determines that first has
Effect diameter thresholding is the maximum value.
In possible embodiment, processor determines the first timing offset value of current area Yu the adjacent cell are as follows:Wherein,P table
Show that total port number, R indicate receiving antenna sum, wherein Γ(r, p)Indicate the first effective diameter thresholding.
In possible embodiment, processor is according to the first timing offset value to the time domain channel estimated result
Timing offset is adjusted, and has process are as follows:
When the corresponding time-domain taps of first timing offset described in the time domain channel estimated result are moved to zero
Each time-domain taps in the time domain channel estimated result are successively translated, obtain time domain channel adjusted and estimate by domain tap
Count result are as follows:, wherein k=0 ..., NFFT- 1, NFFTTable
Show that FFT counts, τ1It indicates the first timing offset value, indicates that the time domain channel of the column pilot tone of port p estimates knot
Fruit.
In possible embodiment, processor determines the process of the second effective diameter thresholding are as follows:
The product for calculating the second noise window power and third coefficient obtains third product, and calculates the peak work
Rate and the product of the 4th coefficient obtain the 4th product;The maximum value in the third product and the 4th product is selected, if really
The fixed maximum value is greater than or equal to the peak power, determines that the second effective diameter thresholding is the peak power, if really
The fixed maximum value is less than the peak power, determines that the second effective diameter thresholding is the maximum value.
In possible embodiment, processor according to the time domain channel estimated result adjusted, described second effectively
Diameter thresholding determines head path position are as follows:
I=-Nleak,…,Nτ, NτIndicate that the time-domain position of time delay maximum diameter, r indicate receiving antenna number index, NFFTIndicate FFT points, p
It indicates port numbers, indicates the call number of the pilot tone column of port p, indicate the second effective diameter thresholding, NleakIt indicates
The N of reservationFFTDiameter item number, (τ '1+τ1) indicate the timing offset, τ1Indicate first timing offset, τ '1Indicate institute
State the second timing offset;
Determine tail footpath position are as follows:Wherein, i=-
Nleak,…,Nτ, r expression receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates the pilot tone of port p
The call number of column indicates the second effective diameter thresholding, NleakIndicate the N retainedFFTDiameter item number, (τ '1+τ1) table
Show the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing offset;
Determine the tail footpath position subtract the first path position it is resulting as a result, by the result be determined as current area with
The delay spread value of the adjacent cell.
Based on the above-mentioned technical proposal, in the embodiment of the present invention, the case where there are time-delay deviations for adjacent cell and current area
Under, channel estimation is carried out according to the CRS of adjacent cell and obtains time domain channel estimated result, determines the of the time domain channel estimated result
One noise window power and peak power are adopted after determining the first effective diameter thresholding according to the first noise window power and peak power
The first timing offset value that thick synchronization gain progress slightly synchronizes is carried out with the first effective diameter thresholding, using the first timing offset value pair
The timing offset of time domain channel estimated result carries out thick synchronous adjustment, determines that the second of time domain channel estimated result adjusted is made an uproar
Sound window power determines the second effective diameter thresholding according to the second noise window power and peak power, using the second effective diameter thresholding
It scans for determining the second timing offset value of precise synchronization to tap search space, is deposited so as to the timing in adjacent area with local area
It is larger in advance or lag may cause effective diameter exit window in the case where, by coarse timing synchronization to time domain channel estimation carry out
Synchronous adjustment so that effective diameter is without falling into noise window, and then obtains effective effective diameter thresholding, and then obtains and relatively accurate determines
When estimation of deviation measurement and delay spread measurement.
Detailed description of the invention
Fig. 1 is the implementation process schematic diagram of existing delay spread algorithm for estimating;
Fig. 2 is the method flow schematic diagram of timing offset estimation in the embodiment of the present invention;
Fig. 3 is the structural schematic diagram of timing offset estimation device in the embodiment of the present invention;
Fig. 4 is terminal structure schematic diagram in the embodiment of the present invention.
Specific embodiment
To make the objectives, technical solutions, and advantages of the present invention clearer, below in conjunction with attached drawing to the present invention make into
It is described in detail to one step, it is clear that described embodiments are only a part of the embodiments of the present invention, rather than whole implementation
Example.Based on the embodiments of the present invention, obtained by those of ordinary skill in the art without making creative efforts
All other embodiment, shall fall within the protection scope of the present invention.
In the embodiment of the present invention, as shown in Fig. 2, the method detailed process of timing offset estimation is as follows:
Step 201: channel estimation being carried out according to the CRS of the adjacent cell of current area and determines time domain channel estimated result, really
The the first noise window power and peak power of domain channel estimation results.
Specifically, channel estimation is carried out according to the CRS of the adjacent cell of current area and determines time domain channel estimated result, specifically
Are as follows:
According to the CRS of adjacent cell carry out least square (Least Square, LS) estimation obtain channel estimation in frequency domain as a result,
Channel estimation in frequency domain result is expressed as formula (1):
Wherein, r indicates that receiving antenna number index, p indicate antenna end slogan index,Indicate the pilot tone columns of port p,
Assuming that receiving antenna sum is R, total port number is P;
To channel estimation in frequency domain resultInverse discrete Fourier transform is carried out, time domain channel estimated result is obtainedIt is expressed as formula (2):
Wherein,Indicate the column pilot tone of port p
Time domain channel estimated result, NFFTIndicate FFT points, r indicates receiving antenna number index.
Specifically, it is determined that time domain channel estimated result the first noise window power and peak power detailed process such as
Under:
Square of the mould of the time domain channel estimated result of each column pilot tone of each port in time domain channel estimated result is calculated,
It is expressed as formula (3):
Formula (3)
Wherein,Indicate port p column pilot tone when
Domain channel estimation results, r indicate receiving antenna number index, NFFTIndicate FFT points;
According to square of the mould of the time domain channel estimated result of each column pilot tone of port each in time domain channel estimated result,
Determine that the first noise window power is shown in formula (4):
Wherein, NτIndicate the time-domain position of time delay maximum diameter, NleakIndicate the N retainedFFTDiameter item number;
According to square of the mould of the time domain channel estimated result of each column pilot tone of port each in time domain channel estimated result,
Determine that peak power is shown in formula (5):
Step 202: the first effective diameter thresholding being determined according to the first noise window power and peak power, according to time domain channel
Estimated result and the first effective diameter thresholding determine the first timing offset value of current area and adjacent cell.
Specifically, it is determined that the process of the first effective diameter thresholding are as follows: calculate the product of the first noise window power and the first coefficient
The first product is obtained, and calculating peak power and the product of the second coefficient obtain the second product;Select the first product and second
Maximum value in product, however, it is determined that the maximum value is greater than or equal to the peak power, determines that the first effective diameter thresholding is the peak value
Power, however, it is determined that the maximum value is less than the peak power, determines that the first effective diameter thresholding is the maximum value.
Wherein, the first coefficient and the second coefficient can be determined by emulation.
First effective diameter thresholding is indicated with formula (6) are as follows:
Wherein,Indicate the first noise window power,Indicate peak power, βnoiseIndicate the first coefficient, βmaxTable
Show the second coefficient.If met according to the first effective diameter thresholding that formula (6) determineThen have again to first
Imitate diameter thresholding assignment are as follows:
Specifically, according to time domain channel estimated result and the first effective diameter thresholding, current area and adjacent cell are determined
First timing offset value, detailed process are as follows:
The the first timing offset value for determining current area and adjacent cell is shown in formula (7):
Wherein,I=-
Nleak,…,Nτ, P indicates total port number, and R indicates receiving antenna sum, wherein Γ(r,p)Indicate the first effective diameter thresholding.Its
In, physical significance be in i=-Nleak,…,NτSearch range in find so that being greater than or equal to
Γ(r,p)Minimum index.
Step 203: the timing offset of time domain channel estimation results being adjusted according to the first timing offset value, determines and adjusts
Second noise window power of the time domain channel estimated result after whole determines second according to the second noise window power and peak power
Effective diameter thresholding.
Wherein, the value range of noise window is to preset.
Specifically, the timing offset of time domain channel estimation results is adjusted according to the first timing offset value, specifically:
The corresponding time-domain taps of first timing offset are moved to zero time-domain taps and obtain the estimation of the second time domain channel
As a result for shown in formula (8):
Wherein, k=0 ..., NFFT- 1, NFFTIndicate FFT points, τ1Indicate the first timing offset value,Indicate port
The of pThe time domain channel estimated result of column pilot tone.
Respectively according to formula (4) and formula (5), according to time domain channel estimated result adjusted, to every receiving antenna
Each port is in noise window [Nτ:NFFT-Nleak] carry out noise power calculation in range and obtain the second noise window power
Third coefficient, which is arranged, isThe 4th coefficient, which is arranged, isWherein, third coefficient and the 4th coefficient can be true by emulating
It is fixed.
Specifically, it is determined that the process of the second effective diameter thresholding are as follows: calculate the product of the second noise window power and third coefficient
Third product is obtained, and calculating peak power and the product of the 4th coefficient obtain the 4th product;
Select the maximum value in third product and the 4th product, however, it is determined that the maximum value is greater than or equal to peak power, really
Fixed second effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak power, determines the second effective diameter thresholding
For the maximum value.
Second effective diameter thresholding is indicated with formula (9) are as follows:
If met according to the second effective diameter thresholding that formula (9) determineThen again to the second effective diameter
Thresholding assignment are as follows:
Step 204: according to time domain channel estimated result adjusted and the second effective diameter thresholding, to tap search space
The the second timing offset value for scanning for determining current area and adjacent cell, according to the first timing offset value and the second timing offset
It is worth the timing offset determined between current area and adjacent cell.
Wherein, the value range of tap search space be preset, specifically, the value range of tap search space with
The value range of noise window is complementary relationship, it is assumed that search space total length is NFFTIf a part point setting in search space
For spatial noise, then another part is tap search space.
Specifically, it is determined that tap search space [N after the second effective diameter thresholdingFFT-Nleak:NFFT-1,0:Nτ] searched
Rope obtains the second timing offset value τ 1 ' of current area and adjacent cell, is indicated with formula (10) and formula (11) are as follows:
Wherein, i=-Nleak..., Nτ, P indicates total port number, and R indicates receiving antenna sum, whereinIndicate the
Two effective diameter thresholdings.Wherein, the peak power of time domain channel estimated result adjusted and the time domain channel before adjustment are estimated
As a result peak power is identical.
Specifically, calculate the first timing offset value and the second timing offset value and, be determined as resulting currently with value
Timing offset between cell and adjacent cell.
In implementation, it can also be determined according to time domain channel estimated result adjusted, the second effective diameter thresholding and determination
When deviation, to tap search space scan for determine current area and adjacent cell delay spread value.
Specifically, according to time domain channel estimated result adjusted, the second effective diameter thresholding, determine that head path position is formula
(12) shown in:
Wherein, i=-Nleak,…,Nτ, NτIndicate that the time-domain position of time delay maximum diameter, r indicate receiving antenna number index, NFFT
Indicating FFT points, p indicates port numbers,Indicate the call number of the pilot tone column of port p,Indicate the second effective diameter
Thresholding, NleakIndicate the N retainedFFTDiameter item number, (τ '1+τ1) indicate timing offset, τ1Indicate the first timing offset, τ '1Table
Show the second timing offset;
Determine that tail footpath position is shown in formula (13):
Wherein, i=-Nleak,…,Nτ, r expression receiving antenna number index, NFFTIndicating FFT points, p indicates port numbers,Indicate the call number of the pilot tone column of port p,Indicate the second effective diameter thresholding, NleakIndicate the N retainedFFT's
The item number of diameter, (τ '1+τ1) indicate timing offset, τ1Indicate the first timing offset, τ '1Indicate the second timing offset;
Determine tail footpath position subtract first path position it is resulting as a result, by the result be determined as current area and adjacent cell when
Prolong expanding value.
Wherein, in formula (12) and formula (13)Its
In,Indicate the time domain adjusted of the column pilot tone of port p
Channel estimation results, r indicate receiving antenna number index, NFFTIndicate FFT points.
Calculating below by way of two specific embodiments to the timing offset and delay spread that are provided in the embodiment of the present invention
Process is illustrated.
Specific embodiment one, under LTE FEICIC macro-pico deployment scenario, having a bandwidth is 10MHz macrocell
A, having a bandwidth is the Pico cell B of 10MHz, and UE is in the edge of Pico cell, and the CRS by macrocell is capable and experienced
It disturbs, A cell reaches UE and the time delay of B cell arrival UE is advanced by 3us, and specific implementation step is as follows:
Step 1, the A LS for carrying out CRS in adjacent area is estimated, obtains channel estimation in frequency domain result
Wherein,R indicates that receiving antenna number index, p indicate antenna end slogan rope
Draw,Indicate the pilot tone columns of port p, it is assumed that receiving antenna sum is R, and total port number is P.
Step 2, it carries out IDFT to channel estimation in frequency domain result and converts to obtain time domain channel estimated result to be expressed asWherein,Indicate the time domain channel estimation of the column pilot tone of port p
As a result, NFFTIndicate FFT points, r indicates receiving antenna number index, wherein NFFT=256.
Step 3, wherein according to the first noise window general power of calculating and peak power,
Indicate the time domain channel of the column pilot tone of port p
Estimated result, r indicate receiving antenna number index, NFFTIndicate FFT points.NτIndicate the time-domain position of time delay maximum diameter, NleakTable
Show the N of reservationFFTDiameter item number.
Wherein,
Step 4, coarse timing synchronization is carried out, the first timing offset value τ is obtained1。
Specifically, the first effective diameter thresholding is setWherein, table
Show the first noise window power, indicates the first peak power, βnoiseIndicate the first coefficient, βmaxIndicate the second coefficient.Wherein,
βmaxSetting value is greater than βnoise, so that there is the first effect diameter thresholding relatively high, first diameter power is maximum under General System, effective diameter door
Limit the higher relative precision that can guarantee timing estimation.βmaxIt can be determined by emulation.If determine according to formula first has
Diameter thresholding is imitated to meet then again to the first effective diameter thresholding assignment are as follows:
First timing offset value τ1It indicates are as follows:Wherein,P table
Show that total port number, R indicate receiving antenna sum, wherein Γ(r,p)Indicate the first effective diameter thresholding.
Step 5, according to the first timing offset value τ1Calculate the second effective diameter thresholding
Specifically, according to τ1Adjustment physical meaning is that coarse timing synchronization being estimated to, corresponding time-domain taps are mobile
It obtains finally obtaining time domain channel estimated result adjusted to the position of the 0th time-domain taps specific
It is as follows:Wherein, k=0 ..., NFFT- 1, NFFTIt indicates
FFT points, τ1It indicates the first timing offset value, indicates the time domain channel estimated result of the column pilot tone of port p.
Be arranged and to every receiving antenna, each port in noise window [Nτ:NFFT-Nleak]
Being calculated according to the peak work in every receiving antenna, each port for noise power is carried out in range
Rate and noise power determineWherein, and
It can be determined by emulation.Again to second if the second effective diameter thresholding determined according to formula meets
Effective diameter thresholding assignment are as follows:
Step 6, synchro measure is timed to time domain channel estimation and delay spread measures.
Specifically, to tap search space [NFFT-Nleak:NFFT-1,0:Nτ] scan for, obtain Timing Synchronization measured value
Or delay spread measured value, wherein timing offset measured value and delay spread measured value can be respectively set differentWithTo meet the needs of different.
Specifically, timing offset measured value is expressed as τ '1+τ1, τ '1Acquisition process are as follows:Wherein,P table
Show total port number, R indicates receiving antenna sum, wherein indicating the second effective diameter thresholding.Wherein,
Specifically, the acquisition process of delay spread measured value are as follows:
Determine that head path position is
Wherein,
I=-Nleak,…,Nτ, NτIndicate the time-domain position of time delay maximum diameter;
Determine that tail footpath position is
Wherein,
I=-Nleak,…,Nτ;
Determine that tail footpath position subtracts that first path position is resulting as a result, the time delay that the result is current area and adjacent cell expands
Exhibition value.
Specific embodiment two, under LTE FEICIC macro-pico deployment scenario, having a bandwidth is 10MHz macrocell
A, having a bandwidth is the Pico cell B of 10MHz, and UE is in the edge of Pico cell, and the CRS by macrocell is capable and experienced
It disturbs, A cell reaches UE and the time delay of B cell arrival UE has lagged 3us, step 1 in specific implementation process and specific embodiment one
The description of~step 6 is identical, and details are not described herein again.
Based on the same inventive concept, a kind of timing offset estimation device is additionally provided in the embodiment of the present invention, the device
Specific implementation can be found in the description of above method embodiment, and overlaps will not be repeated, as shown in figure 3, the device mainly includes:
First processing module 301, the public reference signal CRS for the adjacent cell according to current area carry out channel estimation
It determines time domain channel estimated result, determines the first noise window power and peak power of the time domain channel estimated result;
Second processing module 302, for determining that first has according to the first noise window power and the peak power
It imitates diameter thresholding and current area and the neighbour is determined according to the time domain channel estimated result and the first effective diameter thresholding
First timing offset value of cell;
Third processing module 303, for being determined according to the first timing offset value the time domain channel estimated result
When deviation be adjusted, the second noise window power of time domain channel estimated result adjusted is determined, according to second noise
Window power and the peak power determine the second effective diameter thresholding;
Fourth processing module 304 is used for according to the time domain channel estimated result adjusted and described second effectively
Diameter thresholding scans for determining the second timing offset value of current area and the adjacent cell, according to institute to tap search space
It states the first timing offset value and the second timing offset value determines timing offset between current area and the adjacent cell.
In implementation, further includes the 5th processing module 305, is used for:
According to time domain channel estimated result, the second effective diameter thresholding and the timing offset adjusted,
Scan for determining the delay spread value of current area and the adjacent cell to tap search space.
In implementation, the first processing module is specifically used for:
Least-squares estimation, which is carried out, according to the CRS of the adjacent cell obtains channel estimation in frequency domain as a result, believing the frequency domain
Road estimated result carries out inverse discrete Fourier transform, obtains the time domain channel estimated result.
In implementation, the first processing module is specifically used for:
Calculate the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, it indicates are as follows:Its
In,Indicate the time domain channel estimation of the column pilot tone of port p
As a result, r indicates receiving antenna number index, NFFTIndicate FFT points;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the first noise window power are as follows:Wherein, Nτ
Indicate the time-domain position of time delay maximum diameter, NleakIndicate the N retainedFFTDiameter item number;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the peak power are as follows:
In implementation, the Second processing module is specifically used for:
The product for calculating the first noise window power and the first coefficient obtains the first product, and calculates the peak work
Rate and the product of the second coefficient obtain the second product;
Select the maximum value in first product and second product, however, it is determined that the maximum value is greater than or equal to the peak
It is worth power, determines that the first effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak power, determines that first has
Effect diameter thresholding is the maximum value.
In implementation, the Second processing module is specifically used for:
Determine the first timing offset value of current area Yu the adjacent cell are as follows:Wherein,P table
Show that total port number, R indicate receiving antenna sum, wherein Γ(r,p)Indicate the first effective diameter thresholding.
In implementation, the third processing module is specifically used for:
When the corresponding time-domain taps of first timing offset described in the time domain channel estimated result are moved to zero
Each time-domain taps in the time domain channel estimated result are successively translated, obtain time domain channel adjusted and estimate by domain tap
Count result are as follows:Wherein, k=0 ..., NFFT- 1, NFFT
Indicate FFT points, τ1It indicates the first timing offset value, indicates the time domain channel estimation of the column pilot tone of port p
As a result.
In implementation, the third processing module is specifically used for:
The product for calculating the second noise window power and third coefficient obtains third product, and calculates the peak work
Rate and the product of the 4th coefficient obtain the 4th product;
Select the maximum value in the third product and the 4th product, however, it is determined that the maximum value is greater than or equal to institute
Peak power is stated, determines that the second effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak value
Power determines that the second effective diameter thresholding is the maximum value.
In implementation, the 5th processing module is specifically used for:
According to the time domain channel estimated result adjusted, the second effective diameter thresholding, head path position is determined are as follows:I=-Nleak,…,
Nτ, NτIndicate that the time-domain position of time delay maximum diameter, r indicate receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates the call number of the pilot tone column of port p, indicates the second effective diameter thresholding, NleakIndicate the N retainedFFT's
The item number of diameter, (τ '1+τ1) indicate the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing partially
Difference;
Determine tail footpath position are as follows:Wherein, i=-
Nleak,…,Nτ, r expression receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates the pilot tone of port p
The call number of column indicates the second effective diameter thresholding, NleakIndicate the N retainedFFTDiameter item number, (τ '1+τ1) table
Show the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing offset;
Determine the tail footpath position subtract the first path position it is resulting as a result, by the result be determined as current area with
The delay spread value of the adjacent cell.
Based on the same inventive concept, a kind of terminal is additionally provided in the embodiment of the present invention, the specific implementation of the terminal can be joined
See the specific descriptions of above method embodiment, overlaps will not be repeated, as shown in figure 4, the terminal mainly includes processor 401
With memory 402, wherein preserve preset program in memory 402, processor 401 is saved for reading in memory 402
Program, according to the program execute following procedure:
Channel estimation, which is carried out, according to the public reference signal CRS of the adjacent cell of current area determines time domain channel estimation knot
Fruit determines the first noise window power and peak power of the time domain channel estimated result;
The first effective diameter thresholding is determined according to the first noise window power and the peak power, according to the time domain
Channel estimation results and the first effective diameter thresholding determine the first timing offset value of current area Yu the adjacent cell;
It is adjusted according to timing offset of the first timing offset value to the time domain channel estimated result, determines and adjust
Second noise window power of the time domain channel estimated result after whole, according to the second noise window power and the peak power
Determine the second effective diameter thresholding;
According to the time domain channel estimated result adjusted and the second effective diameter thresholding, to tap search space
The the second timing offset value for scanning for determining current area and the adjacent cell, according to the first timing offset value and described
Second timing offset value determines the timing offset between current area and the adjacent cell.
In implementation, processor according to the time domain channel estimated result adjusted, the second effective diameter thresholding and
The timing offset scans for determining the delay spread value of current area and the adjacent cell to tap search space.
In implementation, processor according to the CRS of the adjacent cell carry out least-squares estimation obtain channel estimation in frequency domain as a result,
Inverse discrete Fourier transform is carried out to the channel estimation in frequency domain result, obtains the time domain channel estimated result.
In implementation, processor determines the first noise window power and peak power of the time domain channel estimated result, tool
Body process are as follows:
Calculate the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, it indicates are as follows:Its
In,Indicate the time domain channel estimation of the column pilot tone of port p
As a result, r indicates receiving antenna number index, NFFTIndicate FFT points;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the first noise window power are as follows:Wherein,
NτIndicate the time-domain position of time delay maximum diameter, NleakIndicate the N retainedFFTDiameter item number;
According to the mould of the time domain channel estimated result of each column pilot tone of each port in the time domain channel estimated result
Square, determine the peak power are as follows:
In implementation, processor calculates the first noise window power and the product of the first coefficient obtains the first product, and
The product for calculating the peak power and the second coefficient obtains the second product;
Select the maximum value in first product and second product, however, it is determined that the maximum value is greater than or equal to the peak
It is worth power, determines that the first effective diameter thresholding is the peak power, however, it is determined that the maximum value is less than the peak power, determines that first has
Effect diameter thresholding is the maximum value.
In implementation, processor determines the first timing offset value of current area Yu the adjacent cell are as follows:Wherein,P table
Show that total port number, R indicate receiving antenna sum, wherein Γ(r,p)Indicate the first effective diameter thresholding.
In implementation, processor according to the first timing offset value to the timing offset of the time domain channel estimated result into
Row adjustment, has process are as follows:
When the corresponding time-domain taps of first timing offset described in the time domain channel estimated result are moved to zero
Each time-domain taps in the time domain channel estimated result are successively translated, obtain time domain channel adjusted and estimate by domain tap
Count result are as follows:Wherein, k=0 ..., NFFT- 1, NFFT
Indicate FFT points, τ1It indicates the first timing offset value, indicates the time domain channel estimation of the column pilot tone of port p
As a result.
In implementation, processor determines the process of the second effective diameter thresholding are as follows:
The product for calculating the second noise window power and third coefficient obtains third product, and calculates the peak work
Rate and the product of the 4th coefficient obtain the 4th product;The maximum value in the third product and the 4th product is selected, if really
The fixed maximum value is greater than or equal to the peak power, determines that the second effective diameter thresholding is the peak power, if really
The fixed maximum value is less than the peak power, determines that the second effective diameter thresholding is the maximum value.
In implementation, processor is determined according to the time domain channel estimated result adjusted, the second effective diameter thresholding
First path position are as follows:
I=-Nleak,…,Nτ, NτIndicate that the time-domain position of time delay maximum diameter, r indicate receiving antenna number index, NFFTIndicate FFT points, p
It indicates port numbers, indicates the call number of the pilot tone column of port p, indicate the second effective diameter thresholding, NleakIt indicates
The N of reservationFFTDiameter item number, (τ '1+τ1) indicate the timing offset, τ1Indicate first timing offset, τ '1Indicate institute
State the second timing offset;
Determine tail footpath position are as follows:Wherein, i=-
Nleak,…,Nτ, r expression receiving antenna number index, NFFTIndicate FFT points, p indicates port numbers, indicates the pilot tone of port p
The call number of column indicates the second effective diameter thresholding, NleakIndicate the N retainedFFTDiameter item number, (τ '1+τ1) table
Show the timing offset, τ1Indicate first timing offset, τ '1Indicate second timing offset;
Determine the tail footpath position subtract the first path position it is resulting as a result, by the result be determined as current area with
The delay spread value of the adjacent cell.
Wherein, it is connected between processor and memory by bus, bus architecture may include any number of interconnection
The various circuits of bus and bridge, the memory that the one or more processors and memory specifically represented by processor represent link
Together.Bus architecture can also be by various other circuits of such as peripheral equipment, voltage-stablizer and management circuit or the like
It links together, these are all it is known in the art, and therefore, it will not be further described herein.Bus interface mentions
For interface.Processor is responsible for managing bus architecture and common processing, and memory can store processor and execute operation when institute
The data used.
Based on the above-mentioned technical proposal, in the embodiment of the present invention, the case where there are time-delay deviations for adjacent cell and current area
Under, channel estimation is carried out according to the CRS of adjacent cell and obtains time domain channel estimated result, determines the of the time domain channel estimated result
One noise window power and peak power are adopted after determining the first effective diameter thresholding according to the first noise window power and peak power
The first timing offset value that thick synchronization gain progress slightly synchronizes is carried out with the first effective diameter thresholding, using the first timing offset value pair
The timing offset of time domain channel estimated result carries out thick synchronous adjustment, determines that the second of time domain channel estimated result adjusted is made an uproar
Sound window power determines the second effective diameter thresholding according to the second noise window power and peak power, using the second effective diameter thresholding
It scans for determining the second timing offset value of precise synchronization to tap search space, is deposited so as to the timing in adjacent area with local area
It is larger in advance or lag may cause effective diameter exit window in the case where, by coarse timing synchronization to time domain channel estimation carry out
Synchronous adjustment so that effective diameter is without falling into noise window, and then obtains effective effective diameter thresholding, and then obtains and relatively accurate determines
When estimation of deviation measurement and delay spread measurement.
It should be understood by those skilled in the art that, the embodiment of the present invention can provide as method, system or computer program
Product.Therefore, complete hardware embodiment, complete software embodiment or reality combining software and hardware aspects can be used in the present invention
Apply the form of example.Moreover, it wherein includes the computer of computer usable program code that the present invention, which can be used in one or more,
The shape for the computer program product implemented in usable storage medium (including but not limited to magnetic disk storage and optical memory etc.)
Formula.
The present invention be referring to according to the method for the embodiment of the present invention, the process of equipment (system) and computer program product
Figure and/or block diagram describe.It should be understood that can be realized by computer program instructions each in flowchart and/or the block diagram
The combination of process and/or box in process and/or box and flowchart and/or the block diagram.It can provide these computers
Processor of the program instruction to general purpose computer, special purpose computer, Embedded Processor or other programmable data processing devices
To generate a machine, so that generating use by the instruction that computer or the processor of other programmable data processing devices execute
In the dress for realizing the function of specifying in one or more flows of the flowchart and/or one or more blocks of the block diagram
It sets.
These computer program instructions, which may also be stored in, is able to guide computer or other programmable data processing devices with spy
Determine in the computer-readable memory that mode works, so that it includes referring to that instruction stored in the computer readable memory, which generates,
Enable the manufacture of device, the command device realize in one box of one or more flows of the flowchart and/or block diagram or
The function of being specified in multiple boxes.
These computer program instructions also can be loaded onto a computer or other programmable data processing device, so that counting
Series of operation steps are executed on calculation machine or other programmable devices to generate computer implemented processing, thus in computer or
The instruction executed on other programmable devices is provided for realizing in one or more flows of the flowchart and/or block diagram one
The step of function of being specified in a box or multiple boxes.
Obviously, various changes and modifications can be made to the invention without departing from essence of the invention by those skilled in the art
Mind and range.In this way, if these modifications and changes of the present invention belongs to the range of the claims in the present invention and its equivalent technologies
Within, then the present invention is also intended to include these modifications and variations.