NR terminal positioning method

Abstract

The invention provides a positioning method of an NR terminal, and the positioning method comprises the following steps: 1, a positioning server determines a positioning cell list of target UE; step 2, the positioning server selects reference UE; step 3, the positioning server determines a positioning cell list; step 4, configuring positioning detection reference signals for the reference UE and the target UE; step 5, the positioning server calculates the time delay after calibration of the target UE; and step 6, calculating the position of the target UE. The method has the beneficial effects that the time delay measurement of the target UE is calibrated according to the time delay measurement of each base station on the reference UE, so that the accuracy of time delay estimation is improved; meanwhile, clock synchronization errors of different UEs are considered, and the clock synchronization errors are solved as unknown numbers which are the same as coordinates of the target UE, so that the positioning precision is remarkably improved, and the operation complexity of a positioning algorithm is reduced; and the implementation complexity of the base station and the UE is reduced while the positioning precision is ensured.

Description

Technical Field

[0001] The present invention relates to the field of terminal positioning technology, and in particular to a positioning method for an NR terminal. Background Art

[0002] With the widespread application of NR (New Radio), various intelligent scenarios have put forward higher requirements for location-based services. Therefore, NR has enhanced the standard and introduced positioning reference signals to provide support for high-precision positioning outdoors and indoors. For example, by introducing positioning sounding reference signals (Pos-SRS) and positioning reference signals (PRS), base stations can locate users by measuring the uplink time difference of arrival (UL-TDOA), and users can locate themselves by measuring the downlink time difference of arrival (DL-TDOA). Affected by the synchronization error of the base station and various interferences in the wireless channel environment, the base station has errors in measuring the arrival time of the uplink positioning reference signal, which will lead to positioning errors.

[0003] For example, the invention patent application publication number CN113115440A records "a 5G NR positioning calibration method and system", which includes: measuring and calibrating the location information of a 5G terminal at a fixed position within the 5G positioning service area; and calibrating the current position of the terminal to be positioned through a screened positioning algorithm based on the calibrated location information of the 5G terminal at a fixed position and the wireless measurement data uploaded by the 5G terminal at a fixed position. By first measuring and calibrating the position of the 5G terminal at a fixed position, calibrated location information and measurement data are provided, and used as prior information for subsequent positioning calibration to calibrate and improve the positioning accuracy of the 5G terminal to be positioned; the calibration technology of 5G NR positioning accuracy and the indoor and outdoor positioning accuracy based on 5G technology are improved.

[0004] For another example, the invention patent application publication number CN113423061A discloses an invention entitled "Positioning method and device for terminal equipment in 5G network", which provides a method based on improving the accuracy of delay estimation and then using the Chan algorithm to improve the TDOA positioning accuracy. Since the NR standard does not require the clock accuracy of the UE as high as that of the base station, there are certain differences in the frame headers of different UEs. For the calibration positioning method based on the reference UE, this error will greatly reduce the positioning accuracy; the premise of the Chan algorithm is that the measurement error of TDOA is small, but there will be measurement values ​​with large errors in actual propagation, which will affect the positioning accuracy to a certain extent. In order to solve the problem that the positioning accuracy does not meet the expected results by using the reference UE for positioning calibration without considering the clock differences between UEs in the prior art, and the measurement error makes the positioning results of the commonly used Chan algorithm fail to meet expectations.

[0005] For another example, invention patent application number CN202310879007.4 discloses an interference detection method, which is characterized in that it is applied to a base station, including: triggering the activation of a cell reference signal interference assessment NR CRS-IM signal based on an interference detection trigger condition; configuring the working execution parameters of the NR CRS-IM signal to configure the NRCRS-IM signal based on the working execution parameters; sending the activation information of the NR CRS-IM signal and the working execution parameters to the interfered terminal, so that the terminal starts receiving the NR CRS-IM signal based on the activation information; and sending the NRCRS-IM signal to the terminal, so that the terminal performs an interference detection operation on the NR CRS-IM signal based on the working execution parameters; receiving the interference detection result reported by the terminal to locate the interfering cell based on the interference detection result.

[0006] The above-mentioned prior art fails to solve the problem of positioning accuracy caused by errors in the measurement of the arrival time of the uplink positioning reference signal by the base station due to the influence of base station synchronization errors and various interferences in the wireless channel environment. Summary of the invention

[0007] The object of the present invention is to provide a positioning method for an NR terminal, the positioning method for the NR terminal comprising the following steps:

[0008] Step 1. The positioning server determines the positioning cell list of the target UE;

[0009] Step 2. The positioning server selects a reference UE;

[0010] Step 3. The positioning server determines the positioning cell list;

[0011] Step 4. Configure positioning sounding reference signals for the reference UE and the target UE;

[0012] Step 5. The positioning server calculates the calibrated delay of the target UE;

[0013] Step 6. Calculate the location of the target UE.

[0014] Furthermore, in step 1, the positioning server determines a positioning cell list of the target UE, including:

[0015] The positioning server maintains each cell under each base station and a list of base station and cell information that assists in positioning;

[0016] Determine multiple base stations and cell information for assisting in positioning the target UE according to the serving cell where the target UE is located;

[0017] The target UE's serving cell and auxiliary positioning cell constitute the target UE's positioning cell list. The target UE's positioning cell list only includes multiple cells involved in positioning calculation, including a serving cell accessed by the UE and several neighboring cells around the serving cell.

[0018] Further, in step 2, the positioning server selects a reference UE:

[0019] According to the positioning cell list of the target UE, a reference UE is selected, and the positioning cell list of the target UE is required to be a part of or all cells in the positioning cell list of the reference UE.

[0020] Furthermore, in step 3, the positioning server determines a positioning cell list:

[0021] The positioning cell list of the target UE is used as the final positioning cell list.

[0022] Further, in step 4, configuring a positioning sounding reference signal for the reference UE and the target UE includes:

[0023] The positioning server notifies the base station where the service cell of the reference UE and the target UE in the positioning cell list is located, and the base station then notifies the corresponding cell to configure the positioning detection reference signal for the reference UE and the target UE respectively, and notifies all base stations and cells in the positioning cell list of the configuration information; wherein, the configuration of the positioning detection reference signal includes the sending period of the positioning detection reference signal, the starting position in the frequency domain, the bandwidth, the comb division, the code division, the expected power, the path loss compensation factor and the path loss reference signal and other information.

[0024] Furthermore, in step 4, when configuring the positioning detection reference signal, the serving cell configures reasonable power control parameters of the positioning detection reference signal, the power control parameters including expected power, path loss compensation factor and path loss reference signal, etc., to ensure that the signal-to-noise ratio of the positioning detection reference signal received by each cell in the positioning cell list exceeds a predefined threshold value, so as to ensure the accuracy and reliability of the delay measurement.

[0025] Further, in step 5, the positioning server calculates the calibrated delay of the target UE:

[0026] The delay between the reference UE and the target UE measured in each cell in the positioning cell list is reported to the positioning server;

[0027] The positioning server calculates based on the obtained delay, the location of the reference UE, and the location information of each cell in the positioning cell list:

[0028] The distance from the kth cell to the reference UE is denoted as DisRef k , k = 1, 2, 3, 4, ...;

[0029] The kth cell measures the reference UE delay, which is denoted as TaRef k , k = 1, 2, 3, 4, ...;

[0030] The kth cell measures the current UE delay, which is recorded as TaTarget k , k = 1, 2, 3, 4, ...;

[0031] Then the delay of the target UE after calibration is:

[0032] Ta k =TaTarget k -(TaRef k -DisRef k / c), k = 1, 2, 3, 4, ..... N,

[0033] Here, c represents the speed of light.

[0034] Further, in step 6, the location of the target UE is calculated:

[0035] Step 6.1 The multi-point positioning method is to solve the following N (N ≥ 4) equations, as shown below:

[0036] (xx k ) 2 +(yy k ) 2 =c 2 ·(Ta k -t) 2,k=1,2,3,4,...,N...(1),

[0037] Where: (x, y) is the coordinate of the target UE; (x k ,y k ), k = 1, 2, 3, 4, ..., N, corresponding to the coordinates of the kth cell respectively; t represents the clock error between the target UE and the reference UE;

[0038] Step 6.2: Subtract the N equations in equation (1) in step 6.1 from each other to obtain N-1 new equations, as shown in equation (2):

[0039] A·z=b......(2),

[0040] in:

[0041]

[0042] k=1,2,3,...,N-1;R k =c·Ta k ;

[0043] Step 6.3: According to the least squares method, we can get the estimated value of z As shown in formula (3):

[0044]

[0045] Finally, the estimated value of the coordinates (x, y) of the target UE is obtained.

[0046] The present invention has the following beneficial effects:

[0047] 1. The positioning method of the NR positioning terminal of the present invention calibrates the delay measurement of the target UE according to the delay measurement of each base station on the reference UE, thereby improving the accuracy of the delay estimation;

[0048] 2. The positioning method of the NR positioning terminal described in the present invention takes into account the clock synchronization error of different UEs, and solves the clock synchronization error as an unknown number that is the same as the coordinates of the target UE, which significantly improves the positioning accuracy and reduces the computational complexity of the positioning algorithm.

[0049] 3. The positioning method of the NR positioning terminal described in the present invention ensures the positioning accuracy while reducing the implementation complexity of the base station and UE. Among them, the UE is only required to support the sending of the positioning detection reference signal, without measuring the "UE sending and receiving time difference" and reporting it to the positioning server; for the base station, it is required to measure the delay based on the positioning detection reference signal, and there is no need to measure the "gNB sending and receiving time difference" and report it to the positioning server. BRIEF DESCRIPTION OF THE DRAWINGS

[0050] Figure 1 A flowchart of the positioning method of the NR positioning terminal described in the present invention.

[0051] In order to more clearly illustrate the specific technical solutions of the embodiments of the present invention, the specific embodiments of the positioning method of the NR positioning terminal of the present invention are further described in detail below in conjunction with the accompanying drawings of the specification. The described embodiments are only part of the embodiments of the present invention, not all of them. Example

[0052] The technical solutions in the embodiments of the present invention will be described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0053] like Figure 1 As shown, the positioning method of the NR terminal includes the following steps:

[0054] Step 1. The positioning server determines the positioning cell list of the target UE;

[0055] Step 2. The positioning server selects a reference UE;

[0056] Step 3. The positioning server determines the positioning cell list;

[0057] Step 4. Configure positioning sounding reference signals for the reference UE and the target UE;

[0058] Step 5. The positioning server calculates the calibrated delay of the target UE;

[0059] Step 6. Calculate the location of the target UE.

[0060] As an example of some specific steps of the present invention, in step 1, the positioning server determines a positioning cell list of the target UE, including:

[0061] The positioning server maintains each cell under each base station and a list of base station and cell information that assists in positioning;

[0062] Determine multiple base stations and cell information for assisting in positioning the target UE according to the serving cell where the target UE is located;

[0063] The target UE's serving cell and auxiliary positioning cell constitute the target UE's positioning cell list. The target UE's positioning cell list only includes multiple cells involved in positioning calculation, including a serving cell accessed by the UE and several neighboring cells around the serving cell.

[0064] As an example of some specific steps of the present invention, in step 2, the positioning server selects a reference UE:

[0065] According to the positioning cell list of the target UE, a reference UE is selected, and the positioning cell list of the target UE is required to be a part of or all cells in the positioning cell list of the reference UE.

[0066] As an example of some specific steps of the present invention, in step 3, the positioning server determines a positioning cell list:

[0067] The positioning cell list of the target UE is used as the final positioning cell list.

[0068] As an example of some specific steps of the present invention, in step 4, configuring a positioning sounding reference signal for the reference UE and the target UE includes:

[0069] The positioning server notifies the base station where the service cell of the reference UE and the target UE in the positioning cell list is located, and the base station then notifies the corresponding cell to configure the positioning detection reference signal for the reference UE and the target UE respectively, and notifies all base stations and cells in the positioning cell list of the configuration information; wherein, the configuration of the positioning detection reference signal includes the sending period of the positioning detection reference signal, the starting position in the frequency domain, the bandwidth, the comb division, the code division, the expected power, the path loss compensation factor and the path loss reference signal and other information.

[0070] As an example of some specific steps of the present invention, in step 4, when configuring the positioning detection reference signal, the serving cell configures reasonable power control parameters of the positioning detection reference signal, and the power control parameters include expected power, path loss compensation factor and path loss reference signal, etc., to ensure that the signal-to-noise ratio of the positioning detection reference signal received by each cell in the positioning cell list exceeds a predefined threshold value, so as to ensure the accuracy and reliability of the delay measurement.

[0071] As an example of some specific steps of the present invention, in step 5, the positioning server calculates the calibrated delay of the target UE:

[0072] The delay between the reference UE and the target UE measured in each cell in the positioning cell list is reported to the positioning server;

[0073] The positioning server calculates based on the obtained delay, the location of the reference UE, and the location information of each cell in the positioning cell list:

[0074] The distance from the kth cell to the reference UE is denoted as DisRef k , k = 1, 2, 3, 4, ...;

[0075] The kth cell measures the reference UE delay, which is denoted as TaRef k , k = 1, 2, 3, 4, ...;

[0076] The kth cell measures the current UE delay, which is recorded as TaTargetk , k = 1, 2, 3, 4, ...;

[0077] Then the delay of the target UE after calibration is:

[0078] Ta k =TaTarget k -(TaRef k -DisRef k / c), k=1,2,3,4,...

[0079] Here, c represents the speed of light.

[0080] As an example of some specific steps of the present invention, in step 6, the location of the target UE is calculated:

[0081] Step 6.1 The multi-point positioning method is to solve the following N (N ≥ 4) equations, as shown below:

[0082] (xx k ) 2 +(yy k ) 2 =c 2 ·(Ta k -t) 2 ,k=1,2,3,4,...,N...(1),

[0083] Where: (x, y) is the coordinate of the target UE; (x k ,y k ), k = 1, 2, 3, 4, ..., N, corresponding to the coordinates of the kth cell respectively; t represents the clock error between the target UE and the reference UE;

[0084] Step 6.2: Subtract the N equations in equation (1) in step 6.1 from each other to obtain N-1 new equations, as shown in equation (2):

[0085] A·z=b......(2),

[0086] in:

[0087]

[0088] k=1,2,3,...,N-1;R k =c·Ta k ;

[0089] Step 6.3: According to the least squares method, we can get the estimated value of z As shown in formula (3):

[0090]

[0091] Finally, the estimated value of the coordinates (x, y) of the target UE is obtained.

[0092] The preferred embodiments of the present invention disclosed above are only used to help explain the present invention. The preferred embodiments do not describe all the details in detail, nor do they limit the invention to only the specific implementation methods described. The specific embodiments selected and specifically described in this specification are to better explain the principles and practical applications of the present invention, so that technicians in the relevant technical field can better understand and utilize the present invention.

Claims

1. A method for positioning a NR terminal, wherein the method for positioning a NR terminal comprises: The following steps are involved: Step 1. The positioning server determines the positioning cell list of the target UE; Step 2. The positioning server selects a reference UE; Step 3. The positioning server determines the positioning cell list; Step 4. Configure positioning sounding reference signals for the reference UE and the target UE; Step 5. The positioning server calculates the calibrated delay of the target UE; Step 6. Calculate the location of the target UE.

2. The NR terminal positioning method according to claim 1, characterized in that: In step 1, the positioning server determines a positioning cell list of the target UE, including: The positioning server maintains each cell under each base station and a list of base station and cell information that assists in positioning; Determine multiple base stations and cell information for assisting in positioning the target UE according to the serving cell where the target UE is located; The target UE's serving cell and auxiliary positioning cell constitute the target UE's positioning cell list. The target UE's positioning cell list only includes multiple cells involved in positioning calculation, including a serving cell accessed by the UE and several neighboring cells around the serving cell.

3. The NR terminal positioning method according to claim 1, characterized in that: In step 2, the positioning server selects a reference UE, specifically: According to the positioning cell list of the target UE, a reference UE is selected, and the positioning cell list of the target UE is required to be a part of or all cells in the positioning cell list of the reference UE.

4. The NR terminal positioning method according to claim 1, characterized in that: In step 3, the positioning server determines the positioning cell list, specifically: The positioning cell list of the target UE is used as the final positioning cell list.

5. The NR terminal positioning method according to claim 1, characterized in that: In step 4, configuring positioning sounding reference signals for the reference UE and the target UE includes: The positioning server notifies the base station where the service cell of the reference UE and the target UE in the positioning cell list is located, and the base station then notifies the corresponding cell to configure the positioning detection reference signal for the reference UE and the target UE respectively, and notifies all base stations and cells in the positioning cell list of the configuration information; wherein, the configuration of the positioning detection reference signal includes the sending period of the positioning detection reference signal, the starting position in the frequency domain, the bandwidth, the comb division, the code division, the expected power, the path loss compensation factor and the path loss reference signal and other information.

6. The NR terminal positioning method according to claim 1, characterized in that: In step 4, when configuring the positioning detection reference signal, the serving cell configures reasonable power control parameters of the positioning detection reference signal. The power control parameters include expected power, path loss compensation factor and path loss reference signal, etc., to ensure that the signal-to-noise ratio of the positioning detection reference signal received by each cell in the positioning cell list exceeds a predefined threshold value, so as to ensure the accuracy and reliability of the delay measurement.

7. The NR terminal positioning method according to claim 1, characterized in that: In step 5, the positioning server calculates the calibrated delay of the target UE: The delay between the reference UE and the target UE measured in each cell in the positioning cell list is reported to the positioning server; The positioning server calculates based on the obtained delay, the location of the reference UE, and the location information of each cell in the positioning cell list: The distance from the kth cell to the reference UE is denoted as DisRef k , k = 1, 2, 3, 4, ...; The kth cell measures the reference UE delay, which is denoted as TaRef k , k = 1, 2, 3, 4, ...; The kth cell measures the current UE delay, which is recorded as TaTarget k , k = 1, 2, 3, 4, ...; Then the delay of the target UE after calibration is: Ta k =TaTarget k -(TaRef k -DisRef k / c),k=1,2,3,4,... Here, c represents the speed of light.

8. The NR terminal positioning method according to claim 1, characterized in that: In step 6, the location of the target UE is calculated: Step 6.1 The multi-point positioning method is to solve the following N (N ≥ 4) equations, as shown below: (xx k ) 2 +(yy k ) 2 =c 2 ·(Are k -t) 2 ,k=1,2,3,4,...,N......(1), Where: (x, y) is the coordinate of the target UE; (x k ,y k ), k = 1, 2, 3, 4, ..., N, corresponding to the coordinates of the kth cell respectively; t represents the clock error between the target UE and the reference UE; Step 6.2: Subtract the N equations in equation (1) in step 6.1 from each other to obtain N-1 new equations, as shown in equation (2): A·z=b......(2), in: Step 6.3: According to the least squares method, we can get the estimated value of z As shown in formula (3): Finally, the estimated value of the coordinates (x, y) of the target UE is obtained.

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