CN102833849B - Positioning method and user equipment - Google Patents

Abstract

The invention discloses a positioning method and user equipment. The method includes: obtaining the number of FFT/IFFT points N _corr used in PRS correlation operations, the N _corr is a predetermined value that does not change with the PRS bandwidth, and the N _corr is less than or equal to 2048; obtaining the IFFT used by the OFDM symbol corresponding to the PRS bandwidth of the cell The number of points N _ifft-ofdm ; when N _ifft-ofdm ≥ N _corr /2, use the normal sampling rate to receive the PRS receiving sequence in this opportunity, generate the PRS local sequence without CP of the cell, and based on the N _corr the The PRS local sequence without CP is correlated with the PRS received sequence received at normal sampling rate to obtain the PRS arrival time of the cell for OTDOA positioning. The positioning method and user equipment of the embodiments of the present invention use the number of FFT/IFFT points N _corr that does not change with the bandwidth of the PRS through PRS correlation operations, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation.

Description

Positioning method and user equipment

technical field

The present invention relates to the communication field, and more particularly, to a positioning method and user equipment.

Background technique

In LTE (Long Term Evolution, long-term evolution) R9 (release9, version 9), it is proposed to transmit PRS (Position Reference Signal, positioning reference signal) to realize OTDOA (Observation Time Difference of Arrival, observation time difference of arrival) positioning technology. OTDOA positioning technology is a terminal-assisted positioning method. That is, the base station transmits the PRS signal, and the terminal receives the PRS signal sent by each base station within the PRS measurement opportunity (occasion), measures the arrival time difference RSTD (Reference Signal Time difference, reference signal time difference) of the PRS signal sent by each base station, and reports it to the base station. The base station performs hyperbolic positioning according to RSTD to obtain the estimated terminal position.

The method for the terminal to measure RSTD is:

1) Measure the arrival time of the PRS signal in the serving cell;

2) Measure the arrival time of the PRS signal of the neighbor cell;

3) The arrival time of the PRS signal of the neighbor cell is subtracted from the arrival time of the PRS signal of the serving cell to obtain the RSTD of each neighbor cell relative to the serving cell.

Among them, the method for the terminal to measure the arrival time of the PRS signal of a single cell is:

1) Receive the OTDOA positioning assistance information sent by the base station.

2) According to the PRS information of the cell in the auxiliary message, multiple PRS subframes are generated one by one. The symbols containing PRS signals are generated by the following method, and other symbols are filled with zeros of the corresponding sampling points.

a. Generate a local PRS frequency domain signal;

b. Use IFFT (Inverse Fast Fourier Transform) to transform the local PRS frequency domain signal into the time domain;

c. Add CP (cyclic prefix, cyclic prefix).

3) Correlate with the received signal, coherently or non-coherently combine the correlators of multiple subframes to obtain the position of the maximum correlation value and obtain the strongest path delay.

4) Estimate the time delay of the earliest path according to the strongest path, and obtain the PRS arrival time of the cell.

Since the PRS arrival time of a single cell is obtained by correlating the received signal with the local PRS signal, the computational complexity is relatively high. If x(n), y(n) is a finite sequence of N length, then the expression related to x(n), y(n) is:

${\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; xy</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; \&tau;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; \&tau;</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\underset{\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; 0</span>}}{\overset{\mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; -</span>\mathrm{<span\; class="notranslate">\; 1</span>}}{\mathrm{<span\; class="notranslate">\; \&Sigma;</span>}}}\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; )</span>\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; no</span>}<span\; class="notranslate">\; +</span>\mathrm{<span\; class="notranslate">\; \&tau;</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 1</span>}<span\; class="notranslate">\; )</span>$

You can use FFT (Fast Fourier Transform, Fast Fourier Transform) and IFFT to speed up the operation. The number of IFFT/FFT points used for fast correlation is N _corr ≥ N+N-1, and the correlation value is:

${\mathrm{<span\; class="notranslate">\; r</span>}}_{\mathrm{<span\; class="notranslate">\; xy</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; IFFT</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; R</span>}}_{\mathrm{<span\; class="notranslate">\; xy</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; IFFT</span>}<span\; class="notranslate">\; (</span>{\mathrm{<span\; class="notranslate">\; x</span>}}^{<span\; class="notranslate">\; *</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; Y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; K</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span>$

$<span\; class="notranslate">\; =</span>\mathrm{<span\; class="notranslate">\; IFFT</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; FFT</span>}<span\; class="notranslate">\; (</span>\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; *</span>\mathrm{<span\; class="notranslate">\; FFT</span>}<span\; class="notranslate">\; (</span>\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; )</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; -</span><span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; 2</span>}<span\; class="notranslate">\; )</span>$

$\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; x</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; x</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span>& \mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; N</span>}\\ \mathrm{<span\; class="notranslate">\; 0</span>}& \mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; corr</span>}}\end{array}\right.$ $\stackrel{<span\; class="notranslate">\; \&OverBar;</span>}{\mathrm{<span\; class="notranslate">\; the\; y</span>}}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span><span\; class="notranslate">\; =</span>\left\{\begin{array}{cc}\mathrm{<span\; class="notranslate">\; the\; y</span>}<span\; class="notranslate">\; (</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; )</span>& \mathrm{<span\; class="notranslate">\; 0</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; <</span>\mathrm{<span\; class="notranslate">\; N</span>}\\ \mathrm{<span\; class="notranslate">\; 0</span>}& \mathrm{<span\; class="notranslate">\; N</span>}<span\; class="notranslate">\; \&le;</span>\mathrm{<span\; class="notranslate">\; k</span>}<span\; class="notranslate">\; <</span>{\mathrm{<span\; class="notranslate">\; N</span>}}_{\mathrm{<span\; class="notranslate">\; corr</span>}}\end{array}\right.$

In order to speed up the operation, usually the number of points N _corr of FFT/IFFT is an integer power of 2.

Since the PRS subframe is a 1ms, each subframe contains multiple PRS symbols. For example, when the PRS bandwidth is 20M, according to the normal sampling rate of 30.72M, the sampling points within 1ms are 30720 points, directly using this fast correlation The method is not realistic.

Contents of the invention

Embodiments of the present invention provide a positioning method and user equipment, which can reduce the demand of FFT/IFFT resources for fast correlation.

In the first aspect, a positioning method is provided. The method includes: obtaining the fast Fourier transform FFT/fast inverse Fourier transform IFFT points N _corr used in the PRS correlation operation of the positioning reference signal, and the N _corr does not vary with the PRS bandwidth. The predetermined value of the change, and the N _corr is less than or equal to 2048; the number of IFFT points N _ifft-ofdm used by the orthogonal frequency division multiplexing OFDM symbol corresponding to the PRS bandwidth of the cell is obtained; when N _ifft-ofdm ≥ N _corr /2, Use the normal sampling rate to receive the PRS receiving sequence in this opportunity, generate the PRS local sequence without the cyclic prefix CP of the cell, and combine the PRS local sequence without the CP with the PRS received at the normal sampling rate based on the N _corr Correlation operation is performed on the sequence to obtain the PRS arrival time of the cell, and the observed time difference of arrival OTDOA positioning is performed.

In a first possible implementation, in combination with the first aspect, the method further includes: when N _ifft-ofdm < N _corr /2, using a normal sampling rate to receive the PRS reception sequence in this opportunity, and generate the cell's The PRS local sequence with CP, based on the N _corr , performs a correlation operation between the local PRS sequence with CP and the received PRS sequence received at a normal sampling rate to obtain the PRS arrival time of the cell for OTDOA positioning.

In a second possible implementation, in combination with the first aspect, the method further includes: when _Nifft-ofdm <N _corr /2, using an oversampling rate to receive the PRS reception sequence in this opportunity, and generate the cell's The oversampled PRS local sequence with CP is correlated with the PRS received sequence received at the oversampling rate based on the N _corr to obtain the PRS arrival time of the cell for OTDOA positioning.

In a third possible implementation manner, in combination with the first aspect or the first or second possible implementation manner of the first aspect, the N _corr is 2048, 1024 or 512.

In the fourth possible implementation, combined with the first aspect or the third possible implementation of the first aspect, based on the N _corr , the PRS local sequence without CP is combined with the PRS received sequence received at the normal sampling rate Carry out correlation operations, the specific implementation is: take the i-th sequence of the PRS local sequence without CP, i is an integer and 0≤i≤slice-1, slice is the number of slices, slice=2N _ifft-ofdm /N _corr , The starting position is _{Lind_i} , _{Lind_i} = _{Lind_i-1} + N _corr /2, _{Lind_0} = 0, the length is N _corr /2, and a zero sequence of N _corr /2 length is added behind to form a local of N _corr length Sequence, perform FFT transformation on the N _corr long local sequence to obtain _Xi (K); take the i-th sequence of the PRS receiving sequence received at the normal sampling rate, the starting position is Y _{ind_i} , Y _{ind_i} =Y _{ind_i-1} + N _corr /2, Y _{ind_0} is the initial value of the starting position of the receiving sequence when the normal sampling does not have CP, the length is N _corr , which constitutes a receiving sequence of N _corr length, and performs FFT transformation on the receiving sequence of N _corr length to obtain Y _i (K ); take the first N _corr /2 length of IFFT(Conj(X _i (K))*Y _i (K)) as the correlation value of N _corr /2 length in the i-th slice of the PRS local sequence without CP r _i (n), 0≤n≤N _corr /2-1; according to A correlation value r(n) of length N _corr /2 of the PRS local sequence without CP is obtained.

In a fifth possible implementation, in combination with the first or third possible implementation of the first aspect, based on the N _corr , the PRS local sequence with CP is compared with the PRS received sequence received at a normal sampling rate Correlation operation, specifically implemented as: take the 0th sequence of the PRS local sequence with CP, the starting position is zero, the length is N _ifft-ofdm +N _cp , N _cp is the CP length, and N _corr -( N _ifft-ofdm +N _cp ) long zero sequence constitutes an N _corr long local sequence, and performs FFT transformation on the N _corr long local sequence to obtain X ₀ (K); take the first PRS received sequence received at a normal sampling rate Segment 0 sequence, the starting position is Y _{ind_cp} , Y _{ind_cp} =Y _{ind_0} -N _cp , Y _{ind_0} is the initial value of the starting position of the receiving sequence when normal sampling without CP, and the length is N _corr , forming a receiving sequence of N _corr length, Perform FFT transformation on the N _corr long received sequence to obtain Y ₀ (K); take the first N _corr /2 length of IFFT(Conj(X ₀ (K))*Y ₀ (K)) as the PRS local sequence with CP N _corr /2 long correlation value r(n), 0≤n≤N _corr /2-1.

In the sixth possible implementation, combined with the second or third possible implementation of the first aspect, based on the N _corr , the oversampled PRS local sequence with CP and the PRS received with the oversampling rate are received Correlation operation is performed on the sequence, and the specific implementation is as follows: take the i-th sequence of the oversampled PRS local sequence with CP, i is an integer and 0≤i≤slice _cp -1, slice _cp is the number of slices, N _upsample is the multiple of the oversampling rate, the starting position is _{Lind_cp_i} , _{Lind_cp_i} = _{Lind_cp_i-1} + N _corr /2, _{Lind_cp_0} = 0, when 0≤i≤slice _cp -2, the length is N _corr /2 , adding a N _corr /2 long zero sequence to form a N _corr long local sequence. When i=slice _cp -1, the length is N _upsample (N _ifft-ofdm +N _cp )-(slice _cp -1) *N _corr /2, add a zero sequence at the back to form a local sequence of N _corr length, perform FFT transformation on the local sequence of N _corr length to obtain _Xi (K); take the i-th received sequence of the PRS received with the oversampling rate Segment sequence, the starting position is Y _{ind_cp_i} , Y _{ind_cp_i} = Y _{ind_cp_i-1} + N _corr /2, Y _{ind_cp_0} = N _upsample (Y _{ind_0} -N _cp ), Y _{ind_0} is the starting position of the receiving sequence when normal sampling does not have CP The initial value, the length is N _corr , which constitutes a receiving sequence of N _corr length, and performs FFT transformation on the receiving sequence of N _corr length to obtain Y _i (K); take IFFT(Conj(X _i (K))*Y _i (K) ) as the correlation value r _i (n) of N _{corr /} 2 length in the i-th slice of the oversampled PRS local sequence with CP, 0≤n≤N _corr /2-1; according to A correlation value r(n) of length N _corr /2 of the oversampled PRS local sequence with CP is obtained.

In the second aspect, a user equipment is provided, including: an acquisition module, used to acquire the fast Fourier transform FFT/fast inverse Fourier transform IFFT points N _corr used in the correlation operation of the positioning reference signal PRS, and the N _corr is not random The predetermined value of the PRS bandwidth change, and the N _corr is less than or equal to 2048, and the number of IFFT points N _ifft-ofdm used by the orthogonal frequency division multiplexing OFDM symbol corresponding to the PRS bandwidth of the cell is obtained; the receiving module is used for N _ifft When _-ofdm ≥ N _corr /2, use the normal sampling rate to receive the PRS reception sequence in this opportunity; the processing module is used to generate the CP without cyclic prefix of the cell when N _ifft-ofdm ≥ N _corr /2 The PRS local sequence, based on the N _corr, correlates the PRS local sequence without CP with the PRS received sequence received at a normal sampling rate to obtain the PRS arrival time of the cell, and perform OTDOA positioning.

In the first possible implementation, in combination with the second aspect, the receiving module is also used to receive the PRS receiving sequence in this opportunity at a normal sampling rate when N _ifft-ofdm < N _corr /2; the processing module It is also used to generate the PRS local sequence with CP of the cell when N _ifft-ofdm <N _corr /2, and correlate the PRS local sequence with CP with the PRS received sequence received at the normal sampling rate based on the N _corr operation to obtain the PRS arrival time of the cell for OTDOA positioning.

In a second possible implementation, in combination with the second aspect, the receiving module is also configured to use an oversampling rate to receive the PRS receiving sequence in this opportunity when _Nifft-ofdm < _Ncorr /2; the processing module It is also used to generate the oversampled PRS local sequence with CP of the cell when N _ifft-ofdm < N _corr /2, and based on the N _corr , combine the oversampled PRS local sequence with CP with the PRS received at the oversampling rate Correlation calculations are performed on the received sequence to obtain the PRS arrival time of the cell for OTDOA positioning.

In a third possible implementation manner, in combination with the second aspect or the first or second possible implementation manner of the second aspect, the N _corr is 2048, 1024 or 512.

In the fourth possible implementation manner, in combination with the second aspect or the third possible implementation manner of the second aspect, the processing module is specifically configured to obtain the i-th sequence of the PRS local sequence without CP, i is an integer and 0≤i≤slice-1, slice is the number of slices, slice=2N _ifft-ofdm /N _corr , the starting position is _{Lind_i} , _{Lind_i} =L _{ind_i-1} +N _corr /2, _{Lind_0} =0 , the length is N _corr /2, adding N _corr /2 long zero sequence in the back to form a N _corr long local sequence, and performing FFT transformation on the N _corr long local sequence to obtain _Xi (K); take the normal sampling rate The i-th sequence of the received PRS receiving sequence, the starting position is Y _{ind_i} , Y _{ind_i} = Y _{ind_i-1} + N _corr /2, Y _{ind_0} is the initial value of the starting position of the receiving sequence when normal sampling does not have CP, and the length is N _corr , constitute the N _corr long receiving sequence, and perform FFT transformation on the N _corr long receiving sequence to obtain Y _i (K); take the first N _corr of IFFT(Conj(X _i (K))*Y _i (K)) /2 length as the correlation value r _i (n) of N _corr /2 length in the i-th slice of the PRS local sequence without CP, 0≤n≤N _corr /2-1; according to A correlation value r(n) of length N _corr /2 of the PRS local sequence without CP is obtained.

In the fifth possible implementation manner, in combination with the first or third possible implementation manner of the second aspect, the processing module is specifically configured to take the 0th sequence of the PRS local sequence with CP, and start The position is zero, the length is N _ifft-ofdm +N _cp , N _cp is the CP length, and a zero sequence of N _corr -(N _ifft-ofdm +N _cp ) length is added behind to form a local sequence of N _corr length, and N Perform FFT transformation on the local sequence with long _corr to obtain X ₀ (K); take the 0th sequence of the PRS receiving sequence received at the normal sampling rate, the starting position is Y _{ind_cp} , Y _{ind_cp} =Y _{ind_0} -N _cp , Y _{ind_0} is The initial value of the starting position of the receiving sequence when normal sampling does not have a CP, the length is N _corr , which constitutes a receiving sequence of N _corr long, and performs FFT transformation on the receiving sequence of N _corr long to obtain Y ₀ (K); take IFFT(Conj(X ₀ (K))*Y ₀ (K)) The first N _corr /2 length is used as the correlation value r(n) of the PRS local sequence N _corr /2 length with CP, 0≤n≤N _corr /2-1 .

In a sixth possible implementation manner, in combination with the second or third possible implementation manner of the second aspect, the processing module is specifically configured to obtain the i-th sequence of the oversampled PRS local sequence with CP, i is an integer and 0≤i≤slice _cp -1, slice _cp is the number of slices, N _upsample is the multiple of the oversampling rate, the starting position is _{Lind_cp_i} , _{Lind_cp_i} = _{Lind_cp_i-1} + N _corr /2, _{Lind_cp_0} = 0, when 0≤i≤slice _cp -2, the length is N _corr /2 , adding a N _corr /2 long zero sequence to form a N _corr long local sequence. When i=slice _cp -1, the length is N _upsample (N _ifft-ofdm +N _cp )-(slice _cp -1) *N _corr /2, add a zero sequence at the back to form a local sequence of N _corr length, perform FFT transformation on the local sequence of N _corr length to obtain _Xi (K); take the i-th received sequence of the PRS received with the oversampling rate Segment sequence, the starting position is Y _{ind_cp_i} , Y _{ind_cp_i} = Y _{ind cp i-1} + N _corr /2, Y _{ind_cp_0} = N _upsample (Y _{ind_0} -N _cp ), Y _{ind_0} is the start of receiving sequence when normal sampling without CP The initial value of the starting position, the length is N _corr , constitutes the N _corr long receiving sequence, and performs FFT transformation on the N _corr long receiving sequence to obtain Y _i (K); take IFFT(Conj(X _i (K))*Y _i ( The first N _corr /2 length of K)) is used as the correlation value r _i (n) of N _corr /2 length in the i-th slice of the oversampled PRS local sequence with CP, 0≤n≤N _corr /2-1 ;according to A correlation value r(n) of length N _corr /2 of the oversampled PRS local sequence with CP is obtained.

Based on the above technical solution, the positioning method and user equipment of the embodiment of the present invention use the FFT/IFFT points N _corr that do not change with the PRS bandwidth through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the impact of fast correlation on FFT/IFFT resources demand.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following will briefly introduce the accompanying drawings required in the embodiments of the present invention. Obviously, the accompanying drawings in the following description are only some embodiments of the present invention. For Those of ordinary skill in the art can also obtain other drawings based on these drawings without making creative efforts.

Fig. 1 is a schematic flowchart of a positioning method according to an embodiment of the present invention.

Fig. 2 is another schematic flowchart of a positioning method according to an embodiment of the present invention.

Fig. 3 is another schematic flowchart of a positioning method according to an embodiment of the present invention.

Fig. 4 is a schematic block diagram of a user equipment according to an embodiment of the present invention.

Fig. 5 is a schematic block diagram of a user equipment according to another embodiment of the present invention.

Detailed ways

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

It should be understood that the technical solutions of the embodiments of the present invention can be applied to various communication systems that use OFDM (Orthogonal Frequency Division Multiplex, Orthogonal Frequency Division Multiplex) reference signals for positioning, for example: Long Term Evolution (Long Term Evolution, referred to as " LTE") system, LTE Frequency Division Duplex (Frequency Division Duplex, referred to as "FDD") system, LTE Time Division Duplex (Time Division Duplex, referred to as "TDD"), Worldwide Interoperability for Microwave Access , referred to as "WiMAX") communication system, etc.

It should also be understood that in this embodiment of the present invention, a user equipment (User Equipment, referred to as "UE") may communicate with one or more core networks via a radio access network (Radio Access Network, referred to as "RAN"), For example, the user equipment may be a mobile phone, a computer, etc. For example, the user equipment may also be a portable, pocket, hand-held, computer built-in or vehicle-mounted wireless transceiver device, which exchanges voice and/or data with the wireless access network.

The signal in the embodiment of the present invention refers to the baseband digital signal. Therefore, after the signal is sampled at a certain sampling rate, it is represented as a discrete sequence in mathematical form. If the length of this sequence is the length of a symbol, it is also called a symbol. If the sequence The length of is the length of a subframe, also called a subframe, and so on.

Fig. 1 shows a schematic flowchart of a positioning method 100 according to an embodiment of the present invention. The method 100 is executed by the user equipment, as shown in FIG. 1, the method 100 includes:

S110. Obtain the fast Fourier transform FFT/fast inverse Fourier transform IFFT point number N _corr used in the positioning reference signal PRS correlation operation, where the N _corr is a predetermined value that does not change with the PRS bandwidth, and the N _corr is less than or equal to 2048;

S120, acquiring the number of IFFT points N _ifft-ofdm used by the OFDM symbol corresponding to the PRS bandwidth of the cell;

S130, when N _ifft-ofdm ≥ N _corr /2, use the normal sampling rate to receive the PRS reception sequence in this opportunity, generate the PRS local sequence without cyclic prefix CP of the cell, and based on the N _corr , the PRS without CP The PRS local sequence of the CP is correlated with the PRS received sequence received at a normal sampling rate to obtain the PRS arrival time of the cell, and perform OTDOA positioning.

In OTDOA positioning, the PRS arrival time of a single cell is obtained by correlating the received signal with the local PRS signal, and the correlation operation uses FFT and IFFT to speed up the operation. Since each subframe of the PRS contains multiple PRS symbols, it is not realistic to directly use a fast correlation method. Therefore, it is necessary to correlate each OFDM symbol in the subframe respectively. Correlation values in each OFDM symbol are coherently combined to obtain correlation values in the entire subframe.

The PRS symbol adopts IFFT to realize OFDM modulation. Different PRS bandwidths according to the protocol correspond to different IFFT points N _ifft-ofdm , for example, the IFFT points corresponding to the 1.4/3/5/10/15/20M system bandwidth are 128/256/512/1024/2048/2048. However, in order to resist multipath extension, a CP needs to be added in front of each OFDM symbol, and the length is N _cp , so adding one symbol length of the CP does not satisfy the integer power of 2.

In order to realize the correlation between a received PRS symbol and a local PRS symbol, for the case of local sequence without CP, N _corr =2N _ifft-ofdm , and the correlation value of N _ifft-ofdm points can be obtained at one time. 1.4/3/5/10/15/20M system bandwidth corresponds to 256/512/1024/2048/2048/4096 FFT/IFFT points used in the correlation, which can satisfy the integer power of 2. For the case of local sequence with CP, in order to satisfy N _corr ≥(N _ifft-ofdm +N _cp )+(N _ifft-ofdm +N _cp )-1, when N _corr =4N _ifft-ofdm , one can obtain N _corr -(N _ifft-ofdm +N _cp ) point correlation value, for 1.4/3/5/10/15/20M system bandwidth, the corresponding FFT/IFFT points used in the correlation are 512/1024/2048/2048/ 4096/8192, can meet the integer power of 2.

Since the implementation complexity is determined by the maximum bandwidth, the maximum resource required for local sequence band CP correlation is 8192 points of IFFT/FFT resources. The local sequence without CP correlation requires a maximum resource of 4096 IFFT/FFT resources. In order to generate local OFDM signals corresponding to PRSs with different bandwidths, the maximum number of IFFT points is 2048 points. Therefore, directly adopting the fast correlation algorithm will lead to an increase of IFFT resources.

In the embodiment of the present invention, in order to reduce the requirement of fast correlation on FFT/IFFT resources, the number of FFT/IFFT points N _corr adopts a predetermined value less than or equal to 2048 that does not change with the PRS bandwidth. That is to say, for different PRS bandwidth configurations, the same N _corr is used, and N _corr does not exceed the maximum number of IFFT points 2048 required for OFDM symbol generation. In addition, the user equipment determines whether to carry CP correlation according to the size of the PRS bandwidth of the cell. The user equipment obtains the number of IFFT points N _ifft-ofdm used by the OFDM symbol corresponding to the PRS bandwidth of the cell according to the PRS bandwidth of the cell. Since N _corr adopts a predetermined value that does not change with the PRS bandwidth, it can be determined by the size relationship between N _ifft-ofdm and N _corr Determine whether to bring CP correlation. When N _ifft-ofdm ≥ N _corr /2, the PRS bandwidth of the cell is large, and the user equipment uses a normal sampling rate (such as the Nyquist sampling rate) to receive the PRS receiving sequence in this opportunity. Using normal sampling rate means not using oversampling rate, for example, for 20M and 15M bandwidth, use 30.72M sampling rate, 10M bandwidth, use 15.36M sampling rate, 5M bandwidth, use 7.68M sampling rate, and 3M bandwidth, use 3.84M sampling rate Rate, 1.4M bandwidth with 1.92M sampling rate, corresponding to a subframe of 1ms, there are 30720 points, 15360 points, 7680 points, 3840 points, 1920 points of sampling points respectively. The user equipment generates the PRS local sequence without CP of the cell, and then performs a correlation operation between the local PRS sequence without CP and the received PRS sequence received at a normal sampling rate based on the N _corr to obtain the PRS arrival time of the cell , perform OTDOA positioning. Because the number of FFT/IFFT points N _corr used in the correlation operation is a predetermined value not exceeding 2048, the high requirement of fast correlation on FFT/IFFT specifications is reduced.

Therefore, the positioning method of the embodiment of the present invention uses the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for fast correlation on FFT/IFFT resources.

In the embodiment of the present invention, N _corr is preferably 2048, 1024 or 512. Correspondingly, the preferred value of the local sequence slice length N _corr /2 is 1024, 512 or 256. Because the operation efficiency of IFFT/FFT with small number of points is lower than that of IFFT/FFT with larger number of points, therefore, from the perspective of operation efficiency, N _corr =2048 is the optimal value without increasing IFFT resources, but considering the memory Requirements, N _corr =1024, or N _corr =512 will save more memory.

In S130, when N _ifft-ofdm ≥ N _corr /2, the user equipment uses the normal sampling rate to receive the PRS reception sequence in this opportunity, generates the PRS local sequence without CP of the cell, and based on the N _corr The PRS local sequence without CP is correlated with the PRS received sequence received at normal sampling rate to obtain the PRS arrival time of the cell for OTDOA positioning.

When N _ifft-ofdm ≥ N _corr /2, the PRS bandwidth of the cell is large, the oversampling mode is not adopted, and the normal sampling mode is adopted, and the user equipment receives the PRS receiving sequence in this opportunity at the normal sampling rate. Because the PRS bandwidth of the cell is large, the mode without CP is adopted, and the user equipment generates the PRS local sequence without CP of the cell and the received sequence to perform correlation calculation. According to the PRS information of the cell in the OTDOA positioning assistance information sent by the base station, the user equipment generates local PRS frequency domain signals in the corresponding subframe and on the corresponding bandwidth one by one, and then uses IFFT to transform the local PRS frequency domain signal into the time domain. Add CP to obtain the PRS local sequence without CP of the cell, where the number of IFFT points is N _ifft-ofdm , that is, the length of the local sequence is N _ifft-ofdm . Then, based on the N _corr , the user equipment performs a correlation operation on the PRS local sequence without CP and the PRS received sequence received at a normal sampling rate to obtain a correlation value, thereby obtaining the PRS arrival time of the cell for OTDOA positioning. Optionally, based on the N _corr , performing a correlation operation on the PRS local sequence without CP and the PRS received sequence received at a normal sampling rate, including:

Take the i-th sequence of the PRS local sequence without CP, i is an integer and 0≤i≤slice-1, slice is the number of slices, slice=2N _ifft-ofdm /N _corr , the starting position is L _{ind_i} , L _{ind_i} =L _{ind_i-1} +N _corr /2, _{Lind_0} =0, the length is N _corr /2, and a zero sequence of N _corr /2 length is added behind to form a local sequence of N _corr length, and the local sequence of N _corr length Perform FFT transformation on the sequence to obtain _Xi (K);

Take the i-th segment of the PRS receiving sequence received at a normal sampling rate, the starting position is Y _{ind_i} , Y _{ind_i} = Y _{ind_i-1} + N _corr /2, Y _{ind_0} is the starting position of the receiving sequence when normal sampling does not have CP The initial value, the length is N _corr , constitutes the N _corr long receiving sequence, performs FFT transformation on the N _corr long receiving sequence to obtain Y _i (K);

Take the first N _corr /2 length of IFFT(Conj(X _i (K))*Y _i (K)) as the correlation value _{r i} of N _corr /2 length in the i-th slice of the PRS local sequence without CP (n), _{0≤n≤Ncorr} /2-1;

according to A correlation value r(n) of length N _corr /2 of the PRS local sequence without CP is obtained.

Specifically, for normal sampling without CP mode, the slice number slice=2N _ifft-ofdm /N _corr . When N _ifft-ofdm ≥ N _corr /2, the minimum number of slices is 1 slice. In order to obtain the N _corr /2 long correlation value r(n) of the local sequence, it is necessary to obtain the N _corr /2 long correlation value r _i (n) in each local sequence slice, and then add them accordingly, namely The method to obtain the correlation value r _i (n) of length N _corr /2 in each local sequence slice is:

1) Take the i-th sequence of the local sequence, the starting position is _{Lind_i} , the length is N _corr /2, and the subsequent N _corr /2 sequence is zero, forming an N _corr long local sequence FFT input, where the initial value of _{Lind_i} is L _{ind_0} is 0, which means to start from the first data of the symbol, and the update method of the starting position of the local sequence is: _{Lind_i} = _{Lind_i-1} + N _corr /2.

2) Input the FFT of the N _corr long local sequence, and perform FFT transformation to obtain _Xi (K).

3) Take the i-th sequence corresponding to the receiving sequence, the starting position is Y _{ind_i} , and the length is N _corr to form the N _corr long receiving sequence FFT input, where the initial value of Y _{ind_i} is Y _{ind_0} , and the starting position of the receiving sequence is The update method is: Y _{ind_i} =Y _{ind_i-1} +N _corr /2.

4) Input the N _corr long received sequence into FFT, and perform FFT transformation to obtain Y _i (K).

5) Conj(X _i (K) multiplied by Y _i (K) or Y _i (K) multiplied by Conj(X _i (K) to obtain N _corr long IFFT input.

6) IFFT(Conj(X _i (K))*Y _i (K)) or IFFT(Y _i (K)*Conj(X _i (K))) to obtain N _corr long IFFT output.

7) Take the first N _corr /2 as r _i (n).

After obtaining all r _i (n), according to A correlation value r(n) of length N _corr /2 is obtained for the entire local sequence.

In the embodiment of the present invention, as shown in FIG. 2, optionally, the method 100 further includes:

S140. When N _ifft-ofdm < N _corr /2, use the normal sampling rate to receive the PRS reception sequence in this opportunity, generate the PRS local sequence with CP of the cell, and localize the PRS with CP based on the N _corr The sequence is correlated with the PRS received sequence received at a normal sampling rate to obtain the PRS arrival time of the cell for OTDOA positioning.

When N _ifft-ofdm <N _corr /2, the PRS bandwidth of the cell is small, and the number of subcarriers containing PRS signals is small, because the correlation with CP can increase the number of sample points involved in the operation and improve the correlation characteristics of the signal. Therefore, this Carrying out correlation with CP in time can guarantee a certain performance. Therefore, when N _ifft-ofdm < N _corr /2, the normal sampling and CP mode can be used, that is, the user equipment uses the normal sampling rate to receive the PRS receiving sequence in this opportunity, and generates the PRS local sequence with CP of the cell Correlate with the received sequence. According to the PRS information of the cell in the OTDOA positioning assistance information sent by the base station, the user equipment generates the local PRS frequency domain signals in the corresponding subframe and on the corresponding bandwidth one by one, and then uses IFFT transformation to transform the local PRS frequency domain signal into the time domain, where The number of IFFT points is N _ifft-ofdm , and CP is added to obtain the PRS local sequence with CP of the cell, that is, the data of the last N _cp length of the ofdm symbol is copied to the head of the ofdm symbol to form a symbol with a length of N _ifft-ofdm + N _cp . Then, based on the N _corr , the user equipment performs a correlation operation on the PRS local sequence with CP and the PRS received sequence received at a normal sampling rate to obtain a correlation value, thereby obtaining the PRS arrival time of the cell for OTDOA positioning. Optionally, based on the N _corr , performing a correlation operation on the PRS local sequence with CP and the PRS received sequence received at a normal sampling rate, including:

Take the 0th sequence of the PRS local sequence with CP, the starting position is zero, the length is N _ifft-ofdm +N _cp , N _cp is the CP length, and N _corr -(N _ifft-ofdm +N _cp is added after ) long zero sequence to form an N _corr long local sequence, and perform FFT transformation on the N _corr long local sequence to obtain X ₀ (K);

Take the 0th sequence of the PRS receiving sequence received at the normal sampling rate, the starting position is Y _{ind_cp} , Y _{ind_cp} = Y _{ind_0} -N _cp , Y _{ind_0} is the initial value of the starting position of the receiving sequence when the normal sampling does not have CP, and the length is N _corr , constitutes an N _corr long receiving sequence, performs FFT transformation on the N _corr long receiving sequence to obtain Y ₀ (K);

Take the first N _corr /2 length of IFFT(Conj(X ₀ (K))*Y ₀ (K)) as the correlation value r(n) of the N _corr /2 length of the PRS local sequence with CP, 0≤n≤ N _corr /2-1.

Specifically, when N _ifft-ofdm < N _corr /2, the length of the local sequence is less than N _corr /2, so for normal sampling, with CP mode, the number of slices is 1. The method to obtain the correlation value r(n) of the local sequence N _corr /2 is as follows:

1) Take the 0th sequence of the local sequence, the starting position is zero, the length is N _ifft-ofdm + N _cp , and the subsequent N _corr -(N _ifft-ofdm + N _cp ) sequence is zero, forming an N _corr long local Sequence FFT input.

2) Input the FFT of the N _corr long local sequence, and perform FFT transformation to obtain X ₀ (K).

3) Take the 0th sequence corresponding to the receiving sequence, the starting position is Y _{ind_cp} , Y _{ind_cp} = Y _{ind_0} -N _cp , the length is N _corr , Y _{ind_0} is the initial starting position of the receiving sequence when normal sampling does not have CP value, which constitutes the N _corr long received sequence FFT input.

4) Input the FFT of the received sequence with a length of N _corr , and perform FFT transformation to obtain Y ₀ (K).

5) Conj(X ₀ (K)) multiplied by Y ₀ (K) or Y ₀ (K) multiplied by Conj(X ₀ (K)) to obtain N _corr long IFFT input.

6) IFFT(Conj(X ₀ (K))*Y ₀ (K)) or IFFT(Y ₀ (K)*Conj(X ₀ (K))) to obtain N _corr long IFFT output.

7) Take the first N _corr /2 as r(n).

Therefore, in the positioning method of the embodiment of the present invention, the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth is used through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation; and, in When the bandwidth is small, the PRS local sequence with CP is generated and the received sequence is correlated with the received sequence, which can improve the positioning performance under the small bandwidth without increasing the IFFT specification.

When the bandwidth is small, in order to enhance the characteristics of the small bandwidth, an oversampling mode may be used. Therefore, in the embodiment of the present invention, as shown in FIG. 3, optionally, the method 100 further includes:

S150, when N _ifft-ofdm < N _corr /2, use the oversampling rate to receive the PRS reception sequence in this opportunity, generate the PRS local sequence of the oversampling band CP of the cell, and based on the N _corr the oversampling band Correlation operation is performed between the PRS local sequence of the CP and the received PRS sequence received with the oversampling rate to obtain the PRS arrival time of the cell for OTDOA positioning.

When N _ifft-ofdm <N _corr /2, the PRS bandwidth of the cell is small, and the positioning performance under small bandwidth can be enhanced by adopting the oversampling mode. The oversampling rate N _upsample can be pre-configured, for example, 2 times the oversampling rate for 3M bandwidth, and 4 times the oversampling rate for 1.4M bandwidth. Therefore, when N _ifft-ofdm <N _corr /2, the oversampling and CP mode can be used, that is, the user equipment uses the oversampling rate to receive the PRS receiving sequence in this opportunity, and generates the oversampling and CP PRS of the cell The local sequence and the received sequence are correlated. According to the PRS information of the cell in the OTDOA positioning assistance information sent by the base station, the user equipment generates local PRS frequency domain signals in the corresponding subframe and on the corresponding bandwidth one by one, and then adds (N _upsample -1)N _{ifft- Ofdm} point zero, carry out N _upsample *N _ifft-ofdm point IFFT, and add CP, the length of CP is N _upsample *N _cp , obtain the PRS local sequence of the oversampling band CP of this community, the length is N _upsample (N _{ifft- ofdm} +N _cp ). Then, based on the N _corr , the user equipment performs a correlation operation on the oversampled PRS local sequence with CP and the PRS received sequence received at an oversampling rate to obtain a correlation value, thereby obtaining the PRS arrival time of the cell for OTDOA positioning. Optionally, based on the N _corr , performing a correlation operation on the oversampled PRS local sequence with CP and the PRS received sequence received at an oversampling rate, including:

Take the i-th sequence of the oversampled PRS local sequence with CP, i is an integer and 0≤i≤slice _cp -1, slice _cp is the number of slices, N _upsample is the multiple of the oversampling rate, the starting position is _{Lind_cp_i} , _{Lind_cp_i} = _{Lind_cp_i-1} + N _corr /2, _{Lind_cp_0} = 0, when 0≤i≤slice _cp -2, the length is N _corr /2 , adding a N _corr /2 long zero sequence to form a N _corr long local sequence. When i=slice _cp -1, the length is N _upsample (N _ifft-ofdm +N _cp )-(slice _cp -1) *N _corr /2, add a zero sequence at the back to form a local sequence of N _corr length, perform FFT transformation on the local sequence of N _corr length to obtain _Xi (K);

Take the i-th sequence of the PRS receiving sequence received with the oversampling rate, the starting position is Y _{ind_cp_i} , Y _{ind_cp_i} =Y _{ind_cp_i-1} +N _corr /2, Y _{ind_cp_0} =N _upsample (Y _{ind_0} -N _cp ), Y _{ind_0} is the initial value of the starting position of the receiving sequence when normal sampling does not have a CP, and the length is N _corr , which constitutes a receiving sequence of N _corr length, and performs FFT transformation on the receiving sequence of N _corr length to obtain Y _i (K);

Take the first N _corr /2 length of IFFT(Conj(X _i (K))*Y _i (K)) as the correlation value r of N _corr /2 length in the i-th slice of the oversampled PRS local sequence with CP _i (n), _{0≤n≤Ncorr} /2-1;

according to A correlation value r(n) of length N _corr /2 of the oversampled PRS local sequence with CP is obtained.

Specifically, for oversampling, with CP mode, the number of slices in, Indicates rounding up. In this case, it is not necessarily a single slice, that is, the number of slices is greater than or equal to 1. In order to obtain the N _corr /2 long correlation value r(n) of the local sequence, it is necessary to obtain the N _corr /2 long correlation value r _i (n) in each local sequence slice, and then add them accordingly, namely The method to obtain the correlation value r _i (n) of length N _corr /2 in each local sequence slice is:

1) Take the i-th sequence of the local sequence, the starting position is _{Lind_cp_i} , the length is N _corr /2, and the subsequent N _corr /2 sequence is zero, forming an N _corr long local sequence FFT input, where the initial value of _{Lind_cp_i} is L _{ind_cp_0} is 0, which means that the first data of the symbol is taken, and the update method of the starting position of the local sequence is: _{Lind_cp_i} = _{Lind_cp_i-1} + N _corr /2. Since the local sequence length in the last slice may be less than N _corr /2, in this case, take the remaining length, that is, when i=slice _cp -1, the length is N _upsample (N _ifft-ofdm +N _cp ) -(slice _cp -1)*N _corr /2, and the others are zeroed to form an N _corr long local sequence FFT input.

2) Input the FFT of the N _corr long local sequence, and perform FFT transformation to obtain _Xi (K).

3) Take the i-th sequence corresponding to the receiving sequence, the starting position is Y _{ind_cp_i} , and the length is N _corr to form the N _corr long receiving sequence FFT input, where the initial value of Y _{ind_cp_i} is Y _{ind_cp_0} = N _upsample (Y _{ind_0} -N _cp ), Y _{ind_0} is the initial value of the starting position of the receiving sequence when the normal sampling does not have CP, and the updating method of the starting position of the receiving sequence is: Y _{ind_cp_i} =Y _{ind_cp_i-1} +N _corr /2.

4) Input the N _corr long received sequence into FFT, and perform FFT transformation to obtain Y _i (K).

5) Conj(X _i (K) multiplied by Y _i (K) or Y _i (K) multiplied by Conj(X _i (K) to obtain N _corr long IFFT input.

6) IFFT(Conj(X _i (K))*Y _i (K)) or IFFT(Y _i (K)*Conj(X _i (K))) to obtain N _corr long IFFT output.

7) Take the first N _corr /2 as r _i (n).

After obtaining all r _i (n), according to A correlation value r(n) of length N _corr /2 is obtained for the entire local sequence.

Therefore, in the positioning method of the embodiment of the present invention, the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth is used through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation; and, in When the bandwidth is small, the oversampled PRS local sequence with CP is generated and the received sequence is correlated with the received sequence, which can enhance the positioning performance under the small bandwidth without increasing the IFFT specification.

The positioning method according to the embodiment of the present invention is described in detail above with reference to FIG. 1 to FIG. 3 , and the user equipment according to the embodiment of the present invention will be described below in conjunction with FIG. 4 and FIG. 5 .

Fig. 4 shows a schematic block diagram of a user equipment 400 according to an embodiment of the present invention. As shown in FIG. 4, the user equipment 400 includes:

The obtaining module 410 is used to obtain the fast Fourier transform FFT/fast inverse Fourier transform IFFT points N _corr used in the PRS correlation operation of the positioning reference signal. The N _corr is a predetermined value that does not change with the PRS bandwidth, and the N _corr is less than Or equal to 2048, and obtain the number of IFFT points N _ifft-ofdm used by the OFDM symbol corresponding to the PRS bandwidth of the cell;

The receiving module 420 is used to receive the PRS receiving sequence in this opportunity at a normal sampling rate when N _ifft-ofdm ≥ N _corr /2;

The processing module 430 is configured to generate a PRS local sequence without a CP of the cell when N _ifft-ofdm ≥ N _corr /2, and combine the PRS local sequence without a CP with a normal sampling rate based on the N _corr Correlation calculation is performed on the received PRS receiving sequence to obtain the PRS arrival time of the cell, and perform OTDOA positioning.

The user equipment in the embodiment of the present invention uses the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation.

In the embodiment of the present invention, optionally, the receiving module 420 is also configured to receive the PRS receiving sequence in this opportunity at a normal sampling rate when N _ifft-ofdm < N _corr /2;

The processing module 430 is further configured to generate a PRS local sequence with a CP of the cell when N _ifft-ofdm <N _corr /2, and combine the PRS local sequence with a CP with the PRS received at a normal sampling rate based on the N _corr Correlation calculations are performed on the received sequence to obtain the PRS arrival time of the cell for OTDOA positioning.

The user equipment in the embodiment of the present invention uses the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation; and, when the bandwidth is small , generate the PRS local sequence with CP and perform correlation operation with the received sequence, which can improve the positioning performance under small bandwidth without increasing the IFFT specification.

In the embodiment of the present invention, optionally, the receiving module 420 is also configured to use an oversampling rate to receive the PRS reception sequence in this opportunity when N _ifft-ofdm < N _corr /2;

The processing module 430 is also used to generate the oversampled PRS local sequence with CP of the cell when N _ifft-ofdm <N _corr /2, and compare the oversampled PRS local sequence with CP based on the N _corr with the oversampled Correlation operation is performed on the PRS receiving sequence received at high rate to obtain the PRS arrival time of the cell for OTDOA positioning.

The user equipment in the embodiment of the present invention uses the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation; and, when the bandwidth is small , generate oversampled PRS local sequence with CP and perform correlation operation with the received sequence, which can enhance the positioning performance in small bandwidth without increasing the IFFT specification.

In this embodiment of the present invention, optionally, the N _corr is 2048, 1024 or 512.

In the embodiment of the present invention, optionally, the processing module 430 is specifically configured to take the i-th sequence of the PRS local sequence without CP, where i is an integer and 0≤i≤slice-1, and slice is the number of slices , slice=2N _ifft-ofdm /N _corr , the starting position is _{Lind_i} , _{Lind_i} =L _{ind_i-1} +N _corr /2, _{Lind_0} =0, the length is N _corr /2, and N _corr /2 is added later The long zero sequence constitutes a long local sequence of N _corr , and performs FFT transformation on the long local sequence of N _corr to obtain _Xi (K); take the i-th sequence of the PRS receiving sequence received at a normal sampling rate, and the starting position is Y _{ind_i} , Y _{ind_i} =Y _{ind_i-1} +N _corr /2, Y _{ind_0} is the initial value of the start position of the receiving sequence when normal sampling does not have CP, and the length is N _corr , which constitutes a receiving sequence of N _{corr length} . Y _i (K) is obtained by performing FFT transformation on the received sequence; take the first N _corr /2 length of IFFT (Conj(X _i (K))*Y _i (K)) as the i-th PRS local sequence without CP Correlation value r _i (n) of N _corr /2 length in the slice, 0≤n≤N _corr /2-1; according to A correlation value r(n) of length N _corr /2 of the PRS local sequence without CP is obtained.

In the embodiment of the present invention, optionally, the processing module 430 is specifically configured to take the 0th sequence of the PRS local sequence with CP, the starting position is zero, and the length is N _ifft-ofdm + N _cp , N _cp is the length of the CP, adding a N _corr -(N _ifft-ofdm +N _cp ) long zero sequence to form a N _corr long local sequence, and performing FFT transformation on the N _corr long local sequence to obtain X ₀ (K); Take the 0th sequence of the PRS receiving sequence received at the normal sampling rate, the starting position is Y _{ind_cp} , Y _{ind_cp} = Y _{ind_0} -N _cp , Y _{ind_0} is the initial value of the starting position of the receiving sequence when the normal sampling does not have CP, and the length is N _corr , constitutes an N _corr long receiving sequence, performs FFT transformation on the N _corr long receiving sequence to obtain Y ₀ (K); take the first N of IFFT(Conj(X ₀ (K))*Y ₀ (K)) _corr /2 length is used as the correlation value r(n) of the PRS local sequence N _corr /2 length with CP, 0≤n≤N _corr /2-1.

In the embodiment of the present invention, optionally, the processing module 430 is specifically configured to take the i-th sequence of the oversampled PRS local sequence with CP, where i is an integer and 0≤i≤slice _cp -1, slice _cp is the number of slices, N _upsample is the multiple of the oversampling rate, the starting position is _{Lind_cp_i} , _{Lind_cp_i} = _{Lind_cp_i-1} + N _corr /2, _{Lind_cp_0} = 0, when 0≤i≤slice _cp -2, the length is N _corr /2 , adding a N _corr /2 long zero sequence to form a N _corr long local sequence. When i=slice _cp -1, the length is N _upsample (N _ifft-ofdm +N _cp )-(slice _cp -1) *N _corr /2, add a zero sequence at the back to form a local sequence of N _corr length, perform FFT transformation on the local sequence of N _corr length to obtain _Xi (K); take the i-th received sequence of the PRS received with the oversampling rate Segment sequence, the starting position is Y _{ind_cp_i} , Y _{ind_cp_i} = Y _{ind_cp_i-1} + N _corr /2, Y _{ind_cp_0} = N _upsample (Y _{ind_0} -N _cp ), Y _{ind_0} is the starting position of the receiving sequence when normal sampling does not have CP The initial value, the length is N _corr , which constitutes a receiving sequence of N _corr length, and performs FFT transformation on the receiving sequence of N _corr length to obtain Y _i (K); take IFFT(Conj(X _i (K))*Y _i (K) ) as the correlation value r _i (n) of N _{corr /} 2 length in the i-th slice of the oversampled PRS local sequence with CP, 0≤n≤N _corr /2-1; according to A correlation value r(n) of length N _corr /2 of the oversampled PRS local sequence with CP is obtained.

The user equipment 400 according to the embodiment of the present invention may correspond to the user equipment in the positioning method according to the embodiment of the present invention, and the above-mentioned and other operations and/or functions of the various modules in the user equipment 400 are respectively in order to realize the For the sake of brevity, the corresponding flow of each method in 3 will not be repeated here.

The user equipment in the embodiment of the present invention uses the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation.

Fig. 5 shows a schematic block diagram of a user equipment 500 according to another embodiment of the present invention. As shown in FIG. 5, the user equipment 500 includes:

The processor 510 is used to obtain the fast Fourier transform FFT/fast inverse Fourier transform IFFT point number N _corr used in the PRS correlation operation of the positioning reference signal. The N _corr is a predetermined value that does not vary with the PRS bandwidth, and the N _corr is less than Or equal to 2048, and obtain the number of IFFT points N _ifft-ofdm used by the OFDM symbol corresponding to the PRS bandwidth of the cell;

The receiver 520 is configured to receive the PRS reception sequence in this opportunity at a normal sampling rate when N _ifft-ofdm ≥ N _corr /2;

The processor 510 is also configured to generate a PRS local sequence without a CP of the cell when N _ifft-ofdm ≥ N _corr /2, and compare the PRS local sequence without a CP with normal sampling based on the N _corr Correlation operation is performed on the PRS receiving sequence received at a high rate to obtain the PRS arrival time of the cell, and perform the observed time difference of arrival OTDOA positioning.

The user equipment in the embodiment of the present invention uses the number of FFT/IFFT points N _corr that does not change with the PRS bandwidth through the PRS correlation operation, and N _corr does not exceed 2048, which can reduce the demand for FFT/IFFT resources for fast correlation.

Optionally, the receiver 520 is also used to receive the PRS reception sequence in this opportunity at a normal sampling rate when N _ifft-ofdm < N _corr /2;

The processor 510 is further configured to generate a PRS local sequence with a CP of the cell when N _ifft-ofdm <N _corr /2, and combine the PRS local sequence with a CP with the PRS received at a normal sampling rate based on the N _corr Correlation calculations are performed on the received sequence to obtain the PRS arrival time of the cell for OTDOA positioning.

Optionally, the receiver 520 is also used to receive the PRS reception sequence in this opportunity with an oversampling rate when N _ifft-ofdm < N _corr /2;

The processor 510 is also configured to generate the oversampled PRS local sequence with CP of the cell when N _ifft-ofdm <N _corr /2, and compare the oversampled PRS local sequence with CP with the oversampled PRS local sequence based on the N _corr Correlation operation is performed on the PRS receiving sequence received at high rate to obtain the PRS arrival time of the cell for OTDOA positioning.

Optionally, the N _corr is 2048, 1024 or 512.

Optionally, the processor 510 is specifically configured to take the i-th sequence of the PRS local sequence without CP, i is an integer and 0≤i≤slice-1, slice is the number of slices, slice=2N _ifft-ofdm /N _corr , the starting position is L _{ind_i} , L _{ind_i} =L _{ind_i-1} +N _corr /2, L _{ind_0} =0, the length is N _corr /2, and a zero sequence of N _corr /2 length is added behind to form N _Corr -long local sequence, perform FFT transformation on the N _corr- long local sequence to obtain _Xi (K); take the i-th sequence of the PRS receiving sequence received at a normal sampling rate, the starting position is Y _{ind_i} , Y _{ind_i} =Y _{ind_i-1} +N _corr /2, Y _{ind_0} is the initial value of the start position of the receiving sequence when normal sampling does not have a CP, the length is N _corr , which constitutes a receiving sequence of N _corr length, which is obtained by performing FFT transformation on the receiving sequence of N _corr length Y _i (K); Take the first N _corr /2 length of IFFT(Conj(X _i (K))*Y _i (K)) as the N _corr /2 in the i-th slice of the PRS local sequence without CP The long correlation value r _i (n), 0≤n≤N _corr /2-1; according to A correlation value r(n) of length N _corr /2 of the PRS local sequence without CP is obtained.

Optionally, the processor 510 is specifically configured to take the 0th segment sequence of the PRS local sequence with CP, the starting position is zero, and the length is N _ifft-ofdm +N _cp , where N _cp is the length of the CP. Add N _corr -(N _ifft-ofdm +N _cp ) long zero sequence to form a N _corr long local sequence, and perform FFT transformation on the N _corr long local sequence to obtain X ₀ (K); take the normal sampling rate received The 0th sequence of the PRS receiving sequence, the starting position is Y _{ind_cp} , Y _{ind_cp} = Y _{ind_0} -N _cp , Y _{ind_0} is the initial value of the starting position of the receiving sequence when normal sampling does not have CP, the length is N _corr , and constitutes N _corr For the long received sequence, perform FFT transformation on the N _corr long received sequence to obtain Y ₀ (K); take the first N _corr /2 length of IFFT(Conj(X ₀ (K))*Y ₀ (K)) as the band The correlation value r(n) of the PRS local sequence N _corr /2 long of the CP, 0≤n≤N _corr /2-1.

Optionally, the processor 510 is specifically configured to take the i-th sequence of the oversampled PRS local sequence with CP, where i is an integer and 0≤i≤slice _cp -1, slice _cp is the number of slices, N _upsample is the multiple of the oversampling rate, the starting position is _{Lind_cp_i} , _{Lind_cp_i} = _{Lind_cp_i-1} + N _corr /2, _{Lind_cp_0} = 0, when 0≤i≤slice _cp -2, the length is N _corr /2 , adding a N _corr /2 long zero sequence to form a N _corr long local sequence. When i=slice _cp -1, the length is N _upsample (N _ifft-ofdm +N _cp )-(slice _cp -1) *N _corr /2, add a zero sequence at the back to form a local sequence of N _corr length, perform FFT transformation on the local sequence of N _corr length to obtain _Xi (K); take the i-th received sequence of the PRS received with the oversampling rate Segment sequence, the starting position is Y _{ind_cp_i} , Y _{ind_cp_i} = Y _{ind_cp_i-1} + N _corr /2, Y _{ind_cp_0} = N _upsample (Y _{ind_0} -N _cp ), Y _{ind_0} is the starting position of the receiving sequence when normal sampling does not have CP The initial value, the length is N _corr , which constitutes a receiving sequence of N _corr length, and performs FFT transformation on the receiving sequence of N _corr length to obtain Y _i (K); take IFFT(Conj(X _i (K))*Y _i (K) ) as the correlation value r _i (n) of N _{corr /} 2 length in the i-th slice of the oversampled PRS local sequence with CP, 0≤n≤N _corr /2-1; according to A correlation value r(n) of length N _corr /2 of the oversampled PRS local sequence with CP is obtained.

The user equipment 500 according to the embodiment of the present invention may correspond to the user equipment in the positioning method according to the embodiment of the present invention, and the above-mentioned and other operations and/or functions of each module in the user equipment 500 are respectively in order to realize the For the sake of brevity, the corresponding flow of each method in 3 will not be repeated here.

It should be understood that in the embodiments of the present invention, the term "and/or" is only an association relationship describing associated objects, indicating that there may be three relationships. For example, A and/or B may mean that A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character "/" in this article generally indicates that the contextual objects are an "or" relationship.

Those of ordinary skill in the art can realize that the units and algorithm steps of the examples described in conjunction with the embodiments disclosed herein can be implemented by electronic hardware, computer software, or a combination of the two. In order to clearly illustrate the relationship between hardware and software Interchangeability. In the above description, the composition and steps of each example have been generally described according to their functions. Whether these functions are executed by hardware or software depends on the specific application and design constraints of the technical solution. Those skilled in the art may use different methods to implement the described functions for each specific application, but such implementation should not be regarded as exceeding the scope of the present invention.

Those skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the above-described system, device and unit can refer to the corresponding process in the foregoing method embodiment, and will not be repeated here.

In the several embodiments provided in this application, it should be understood that the disclosed systems, devices and methods may be implemented in other ways. For example, the device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or May be integrated into another system, or some features may be ignored, or not implemented. In addition, the mutual coupling or direct coupling or communication connection shown or discussed may be indirect coupling or communication connection through some interfaces, devices or units, and may also be electrical, mechanical or other forms of connection.

The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the solution of the embodiment of the present invention.

In addition, each functional unit in each embodiment of the present invention may be integrated into one processing unit, each unit may exist separately physically, or two or more units may be integrated into one unit. The above-mentioned integrated units can be implemented in the form of hardware or in the form of software functional units.

If the integrated unit is realized in the form of a software function unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention is essentially or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of software products, and the computer software products are stored in a storage medium Among them, several instructions are included to make a computer device (which may be a personal computer, a server, or a network device, etc.) execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage media include: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), magnetic disk or optical disk and other media that can store program codes. .

The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily think of various equivalents within the technical scope disclosed in the present invention. Modifications or replacements shall all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (14)

1. A method of positioning, comprising:

fast Fourier Transform (FFT)/fast inverse Fourier transform (IFFT) point number N used for obtaining Positioning Reference Signal (PRS) related operation_corrSaid N is_corrIs a predetermined value that does not vary with the PRS bandwidth, and said N_corrLess than or equal to 2048;

obtaining IFFT point number N adopted by orthogonal frequency division multiplexing OFDM symbol corresponding to PRS bandwidth of cell_ifft-ofdm；

In N_ifft-ofdm≥N_corrWhen the cell is/2, receiving the PRS receiving sequence in the opportunity by adopting a normal sampling rate, generating a PRS local sequence without a Cyclic Prefix (CP) of the cell, and based on the N_corrAnd carrying out correlation operation on the PRS local sequence without the CP and a PRS receiving sequence received by adopting a normal sampling rate so as to obtain the PRS arrival time of the cell and carry out OTDOA positioning of the observed time difference of arrival.

2. The method of claim 1, further comprising:

in N_ifft-ofdm<N_corrWhen the cell is/2, receiving the PRS receiving sequence in the opportunity by adopting a normal sampling rate, generating the PRS local sequence with the CP of the cell, and based on the N_corrAnd carrying out correlation operation on the PRS local sequence with the CP and a PRS receiving sequence received by adopting a normal sampling rate so as to obtain the PRS arrival time of the cell and carry out OTDOA positioning.

3. The method of claim 1, further comprising:

in N_ifft-ofdm<N_corrWhen the cell is in the second time, the PRS receiving sequence in the current opportunity is received by adopting the oversampling rate, the PRS local sequence of the oversampling band CP of the cell is generated, and the N is based on the PRS local sequence_corrAnd carrying out correlation operation on the PRS local sequence of the over-sampling band CP and the PRS receiving sequence received by adopting the over-sampling rate so as to obtain the PRS arrival time of the cell and carry out OTDOA positioning.

4. The method of any one of claims 1 to 3, wherein N is_corr2048, 1024 or 512.

5. The method of claim 1, wherein the basing on the N is based on the N_corrCorrelating the PRS local sequence without the CP with a PRS received sequence received at a normal sampling rate, comprising:

taking the ith segment sequence of the PRS local sequence without the CP, wherein i is an integer and is more than or equal to 0 and less than or equal to slice-1, and slice is the slice number and is 2N_ifft-ofdm/N_corrThe initial position is L_{ind_i}，L_{ind_i}＝L_{ind_i-1}+N_corr/2，L_{ind_0}0, length N_corr2, adding N later_corrA long sequence of zeros, forming N_corrLong local sequence, N_corrFFT conversion is carried out on the long local sequence to obtain X_i(K)；

Taking the ith segment sequence of PRS receiving sequence received by normal sampling rate, and setting the starting position as Y_{ind_i}，Y_{ind_i}＝Y_{ind_i-1}+N_corr/2，Y_{ind_0}For normal sampling, the initial value of the initial position of the receiving sequence without CP is N_corrForm N_corrLong receive sequence, N_corrFFT conversion is carried out on the long receiving sequence to obtain Y_i(K)；

Taking IFFT (Conj (X)_i(K))*Y_i(K) First N of (b)_corr2 as N in the ith slice of the PRS local sequence without CP_corrLong correlation value r_i(n)，0≤n≤N_corr/2-1；

According toObtaining the PRS local sequence N without CP_corrLong correlation value r (n).

6. The method of claim 2, wherein the basing on the N is based on the N_corrPerforming correlation operation on the PRS local sequence with the CP and a PRS receiving sequence received by adopting a normal sampling rate, wherein the correlation operation comprises the following steps:

taking the 0 th segment sequence of the PRS local sequence with the CP, wherein the starting position is zero, and the length is N_ifft-ofdm+N_cp，N_cpFor CP Length, add N later_corr-(N_ifft-ofdm+N_cp) Long sequence of zeros, forming N_corrLong native sequencesIs a reaction of N_corrFFT conversion is carried out on the long local sequence to obtain X₀(K)；

Taking 0 th segment sequence of PRS receiving sequence received by normal sampling rate, and setting the starting position as Y_{ind_cp}，Y_{ind_cp}＝Y_{ind_0}-N_cp，Y_{ind_0}For normal sampling, the initial value of the initial position of the receiving sequence without CP is N_corrForm N_corrLong receive sequence, N_corrFFT conversion is carried out on the long receiving sequence to obtain Y₀(K)；

Taking IFFT (Conj (X)₀(K))*Y₀(K) First N of (b)_corrThe length of 2 is taken as the PRS local sequence N with the CP_corrA long correlation value r (N), 0. ltoreq. n.ltoreq.N_corr/2-1。

7. The method of claim 3, wherein the N is based on_corrCorrelating the PRS local sequence of the over-sample band CP with a PRS received sequence received at an over-sample rate, comprising:

taking the ith segment sequence of the PRS local sequence of the oversampling band CP, i being an integer and being more than or equal to 0 and less than or equal to slice_cp-1，slice_cpThe number of the slices is the number of the slices,N_upsamplethe initial position is L for the multiple of the oversampling rate_{ind_cp_i}，L_{ind_cp_i}＝L_{ind_cp_i-1}+N_corr/2，L_{ind_cp_0}I is not less than 0 and is not less than slice_cpWhen-2, length is taken as N_corr2, adding N later_corrA long sequence of zeros, forming N_corrLong local sequence, in i-slice_cpWhen-1, length is taken as N_upsample(N_ifft-ofdm+N_cp)-(slice_cp-1)*N_corrAnd/2, adding a zero sequence to the sequence to form N_corrLong local sequence, N_corrFFT conversion is carried out on the long local sequence to obtain X_i(K)；

Taking the i-th segment of the PRS received sequence received with the over-sampling rateSequence, start position is Y_{ind_cp_i}，Y_{ind_cp_i}＝Y_{ind_cp_i-1}+N_corr/2，Y_{ind_cp_0}＝N_upsample(Y_{ind_0}-N_cp)，Y_{ind_0}For normal sampling, the initial value of the initial position of the receiving sequence without CP is N_corrForm N_corrLong receive sequence, N_corrFFT conversion is carried out on the long receiving sequence to obtain Y_i(K)；

Taking IFFT (Conj (X)_i(K))*Y_i(K) First N of (b)_corr2 as N in the ith slice of the PRS local sequence of the oversampling band CP_corrLong correlation value r_i(n)，0≤n≤N_corr/2-1；

According toObtaining PRS local sequence N of the oversampling band CP_corrLong correlation value r (n).

8. A user device, comprising:

an obtaining module, configured to obtain FFT/IFFT points N used for PRS correlation operation of positioning reference signals_corrSaid N is_corrIs a predetermined value that does not vary with the PRS bandwidth, and said N_corrLess than or equal to 2048, and obtaining IFFT point number N adopted by orthogonal frequency division multiplexing OFDM symbol corresponding to PRS bandwidth of cell_ifft-ofdm；

A receiving module for receiving at N_ifft-ofdm≥N_corrWhen the PRS receiving sequence is in the opportunity, the PRS receiving sequence in the opportunity is received by adopting a normal sampling rate;

a processing module for processing at N_ifft-ofdm≥N_corrAt/2, generating PRS local sequences without Cyclic Prefix (CP) for the cell based on the N_corrAnd carrying out correlation operation on the PRS local sequence without the CP and a PRS receiving sequence received by adopting a normal sampling rate so as to obtain the PRS arrival time of the cell and carry out OTDOA positioning of the observed time difference of arrival.

9. The UE of claim 8, wherein the receiving module is further configured to receive a message at N_ifft-ofdm<N_corrWhen the PRS receiving sequence is in the opportunity, the PRS receiving sequence in the opportunity is received by adopting a normal sampling rate;

the processing module is further configured to process the data at N_ifft-ofdm<N_corrAt/2, generating PRS local sequence with CP for the cell based on the N_corrAnd carrying out correlation operation on the PRS local sequence with the CP and a PRS receiving sequence received by adopting a normal sampling rate so as to obtain the PRS arrival time of the cell and carry out OTDOA positioning.

10. The UE of claim 8, wherein the receiving module is further configured to receive a message at N_ifft-ofdm<N_corrWhen the PRS receiving sequence is in the opportunity, adopting the oversampling rate to receive the PRS receiving sequence in the opportunity;

the processing module is further configured to process the data at N_ifft-ofdm<N_corrAt/2, generating a PRS local sequence of an oversampled band CP for the cell based on the N_corrAnd carrying out correlation operation on the PRS local sequence of the over-sampling band CP and the PRS receiving sequence received by adopting the over-sampling rate so as to obtain the PRS arrival time of the cell and carry out OTDOA positioning.

11. The UE of any one of claims 8 to 10, wherein N is_corr2048, 1024 or 512.

12. The UE of claim 8, wherein the processing module is specifically configured to take an ith sequence of the PRS local sequence without CP, i is an integer and is greater than or equal to 0 and less than or equal to slice-1, slice is a slice number, and slice is 2N_ifft-ofdm/N_corrThe initial position is L_{ind_i}，L_{ind_i}＝L_{ind_i-1}+N_corr/2，L_{ind_0}0, length N_corr2, adding N later_corrA long sequence of zeros, forming N_corrLong local sequence, N_corrFFT conversion is carried out on the long local sequence to obtain X_i(K) (ii) a Taking the ith segment sequence of PRS receiving sequence received by normal sampling rate, and setting the starting position as Y_{ind_i}，Y_{ind_i}＝Y_{ind_i-1}+N_corr/2，Y_{ind_0}For normal sampling, the initial value of the initial position of the receiving sequence without CP is N_corrForm N_corrLong receive sequence, N_corrFFT conversion is carried out on the long receiving sequence to obtain Y_i(K) (ii) a Taking IFFT (Conj (X)_i(K))*Y_i(K) First N of (b)_corr2 as N in the ith slice of the PRS local sequence without CP_corrLong correlation value r_i(n)，0≤n≤N_corr2-1; according toObtaining the PRS local sequence N without CP_corrLong correlation value r (n).

13. The UE of claim 9, wherein the processing module is specifically configured to take the 0 th segment of the PRS local sequence with CP, start position is zero, and length is N_ifft-ofdm+N_cp，N_cpFor CP Length, add N later_corr-(N_ifft-ofdm+N_cp) Long sequence of zeros, forming N_corrLong local sequence, N_corrFFT conversion is carried out on the long local sequence to obtain X₀(K) (ii) a Taking 0 th segment sequence of PRS receiving sequence received by normal sampling rate, and setting the starting position as Y_{ind_cp}，Y_{ind_cp}＝Y_{ind_0}-N_cp，Y_{ind_0}For normal sampling, the initial value of the initial position of the receiving sequence without CP is N_corrForm N_corrLong receive sequence, N_corrFFT conversion is carried out on the long receiving sequence to obtain Y₀(K) (ii) a Taking IFFT (Conj (X)₀(K))*Y₀(K) First N of (b)_corr2 Length as P of said strip CPRS local sequence N_corrA long correlation value r (N), 0. ltoreq. n.ltoreq.N_corr/2-1。

14. The UE of claim 10, wherein the processing module is specifically configured to take an ith segment of the PRS local sequence of the over-sampled strip CP, i being an integer and 0 ≦ i ≦ slice_cp-1，slice_cpThe number of the slices is the number of the slices,N_upsamplethe initial position is L for the multiple of the oversampling rate_{ind_cp_i}，L_{ind_cp_i}＝L_{ind_cp_i-1}+N_corr/2，L_{ind_cp_0}I is not less than 0 and is not less than slice_cpWhen-2, length is taken as N_corr2, adding N later_corrA long sequence of zeros, forming N_corrLong local sequence, in i-slice_cpWhen-1, length is taken as N_upsample(N_ifft-ofdm+N_cp)-(slice_cp-1)*N_corrAnd/2, adding a zero sequence to the sequence to form N_corrLong local sequence, N_corrFFT conversion is carried out on the long local sequence to obtain X_i(K) (ii) a Taking the ith segment sequence of PRS receiving sequence received by adopting oversampling rate, and setting the starting position as Y_{ind_cp_i}，Y_{ind_cp_i}＝Y_{ind_cp_i-1}+N_corr/2，Y_{ind_cp_0}＝N_upsample(Y_{ind_0}-N_cp)，Y_{ind_0}For normal sampling, the initial value of the initial position of the receiving sequence without CP is N_corrForm N_corrLong receive sequence, N_corrFFT conversion is carried out on the long receiving sequence to obtain Y_i(K) (ii) a Taking IFFT (Conj (X)_i(K))*Y_i(K) First N of (b)_corr2 as N in the ith slice of the PRS local sequence of the oversampling band CP_corrLong correlation value r_i(n)，0≤n≤N_corr2-1; according toObtaining PRS local sequence N of the oversampling band CP_corrLong correlation value r (n).