CN100415044C - A method for realizing wireless terminal positioning in a multi-sector cell - Google Patents

Abstract

The invention discloses a method for realizing wireless terminal positioning in a multi-sector cell. The method includes the following steps: A. The radio network controller RNC determines the cell where the UE is located; B. According to the pre-stored cell information, the RNC judges the cell Whether the cell where the UE is located is a multi-sector cell, if not, locate the UE in this cell; if so, proceed to step C; C. determine the sector where the UE is located, and locate the UE in this sector. In the method of the present invention, by measuring the neighboring cells of the cell where the UE is located, the obtained neighboring cell identifier of the cell where the UE is located is matched with the identifiers of neighboring cells of each sector of the cell where the UE is located that are pre-stored on the network side, and the UE is judged. sector. This method narrows the positioning range and improves the positioning accuracy.

Description

A method for realizing wireless terminal positioning in a multi-sector cell

technical field

The present invention relates to a wireless positioning technology, especially a method for realizing wireless terminal positioning based on a cell positioning mode (CELL_ID) or an enhanced cell positioning mode (CELL_ID+RTT) in a multi-sector cell.

Background technique

The positioning service is an important service in the wireless cellular communication system. There are three main positioning technologies in the third generation wireless communication system (3G): Assisted Global Positioning System (A-GPS) positioning, observed time difference of arrival (OTDOA) positioning and CELL_ID+RTT positioning.

A-GPS positioning requires the wireless terminal (UE) to have a built-in GPS receiver, which cooperates with the network to complete the positioning. The positioning accuracy is the highest, and the wireless terminal needs to be able to face three satellites at the same time; The hyperbolic positioning method is used to complete the positioning, and the mobile phone needs to support OTDOA measurement; CELL_ID+RTT positioning is an enhanced method of CELL_ID positioning, and the positioning of the wireless terminal is completed by determining the distance between the cell where the wireless terminal is located and the base station antenna. .

CELL_ID positioning identifies the location of the UE according to the cell or base station NodeB where the UE is located in the network. The UE may be anywhere in the cell, so the CELL_ID positioning accuracy depends entirely on the size of the cell. In most areas except dense urban areas, the cell radius of the CDMA system is generally more than 1km, especially in the suburbs and rural areas, even reaching more than ten kilometers. At this time, the accuracy of CELL_ID positioning will not be better than 500m, which is far from Can not meet the requirements of most users. Therefore, on the basis of the CELL_ID positioning method, some improved technologies have emerged, such as the CELL_ID+RTT technology, that is, to complete the positioning of the wireless terminal by determining the distance between the cell where the wireless terminal is located and the base station antenna. Although this improved technology can improve the positioning accuracy to a certain extent, the improvement effect is not obvious.

In an actual network, it often occurs that one logical cell corresponds to multiple sectors, as shown in FIG. 1 . According to the principle of minimum gap, when locating a UE, sectors that do not belong to the current cell will be included in the current cell, resulting in the expansion of the sector area and reducing the positioning accuracy. For example, in the situation in Figure 1, assuming that the sector angle corresponding to cell 3 is smaller than the sector angle corresponding to cell 2, sector A, sector B, and sector 3 of cell 1 are combined into one continuous sector, as shown in the figure 1, and treat the merged continuous sectors as the corresponding area of the cell.

Fig. 2 is a flowchart of a wireless terminal positioning method in the CELL_ID+RTT positioning mode in a multi-sector cell in the prior art. It is assumed that the core network (CN) initiates a positioning UE request to the radio network controller (RNC). In conjunction with Fig. 1, it is assumed that the UE In cell 1, the specific steps include:

Step 200: the RNC determines the cell where the UE is located.

In this step, after the CN initiates a request to locate the UE, the RNC will first select an optimal positioning method according to the positioning request. This application involves the CELL_ID+RTT positioning method, so here it is assumed that the positioning method selected by the RNC is CELL_ID+RTT positioning Way.

Afterwards, the RNC inquires whether there is UE state measurement information locally. If there is no RNC, it needs to initiate paging for the UE to complete the state transfer of the UE, so that the UE is transferred from the idle state, such as the URA_PCH state or the IDLE state, to the active state, such as Cell_DCH state or Cell_FACH state. After the UE completes the state transfer, it will report the transfer success message to the RNC. The transfer success message comes from the cell where the UE is located, so the RNC can determine the cell where the UE is located according to the transfer success message; if the RNC locally stores the UE’s state measurement information, the cell where the UE is located is determined according to the status measurement information.

Step 201: the RNC determines the distance between the UE and the base station through measurement.

In this step, the RNC sends a round-trip travel time (RTT) measurement request to the NodeB. _{What the RTT measures is the travel time T total of} the wireless signal from the NodeB _to the UE. to the processing time T _between the radio signal and the return radio signal. After receiving the request, the NodeB reports the RTT measurement result to the RNC after completing the RTT measurement.

The RNC sends a second type of user equipment reception and transmission time difference (Rx-Tx Type2) measurement request to the UE. The Rx-Tx Type2 _measures the processing time T between the UE receiving the wireless signal and returning the wireless signal. After receiving the request, the UE reports the Rx-Tx Type2 measurement result to the RNC after completing the Rx-Tx Type2 measurement.

According to the RTT measurement report and the Rx-Tx Type2 measurement report, the RNC calculates the signal transmission time _Tpass from the UE to the RNC, _{where Tpass} =( _Ttotal -T)/2. The reason for dividing by two here is because the travel time T _{is always} a round-trip process. The RNC calculates the distance d from the UE to the NodeB antenna according to the calculated signal transmission time from the UE to the RNC and the pre-stored wireless signal propagation speed v in the air. The distance d=T _xv .

In this embodiment, through the state measurement in step 200, it is determined that the cell where the UE is located is cell 1, and through the distance measurement in step 201, it is determined that the distance between the UE and the NodeB antenna is d, and the measurement information of these UEs is stored in the database of the RNC middle. It should be noted here that when the UE returns to the idle state, the UE measurement information obtained in steps 200 and 201 and stored in the RNC will be automatically deleted from the RNC database.

Steps 202 to 203: The RNC determines the positioning result according to the pre-stored information of the cell where the UE is located, and then reports it.

In this step, the RNC performs CELL_ID+RTT processing according to the calculated distance d and the pre-stored information of cell 1 to obtain the final positioning result of the UE, and the RNC reports the final positioning result of the UE to the CN.

Wherein, the CELL_ID+RTT process includes: determining the final positioning result of the UE according to the calculated distance d, the coordinates of the NodeB pre-stored in the RNC, and the geometric shape of the corresponding cell. For example, when the pre-stored cell is an omni-directional cell, the final reported positioning result is a circle with the NodeB coordinates as the center and the distance d as the radius, that is, the location of the UE is on this circle; for another example, when the pre-stored When the cell is a sector, the final reported positioning result is a circular arc with the coordinates of NodeB as the center and the distance d as the radius. The direction of the cell is the same.

In this embodiment, the cell 1 where the UE is located includes sector A and sector B. According to the principle of minimum gap, when locating the UE, sector A, sector B and sector 3 of cell 1 will be combined into one continuous sector sector, as shown in the shaded part in Figure 1, and treat the merged continuous sectors as the corresponding area of the cell. Therefore, the final positioning result is: the position of the UE is in the merged sector, with the NodeB as the center and the distance d as the radius.

The above is the wireless terminal positioning method in the CELL_ID+RTT positioning mode in the multi-sector cell in the prior art. From the above method, it can be seen that since there is no specific distinction between whether the UE is located in sector A of cell 1 or in the sector of cell 1 B, the positioning range of the UE is expanded, thereby reducing the positioning accuracy.

In addition, the wireless terminal positioning method in the CELL_ID positioning mode in multi-sector cells in the prior art is a part of the process in FIG. 2 , and step 201 can be omitted, and the final positioning result is that the UE is located in cell 1.

Contents of the invention

In view of this, the main purpose of the present invention is to provide a method for realizing wireless terminal positioning in a multi-sector cell, which can reduce the positioning range and improve the positioning accuracy.

In order to achieve the above object, the technical solution of the present invention is specifically realized in the following way:

A method for realizing positioning of a wireless terminal UE in a multi-sector cell, the method includes the following steps:

A. The radio network controller RNC determines the cell where the UE is located;

B. According to the pre-stored cell information, the RNC judges whether the cell where the UE is located is a multi-sector cell, if not, locates the UE in the cell; if so, enters step C;

C. According to the measurement information, determine the neighbor cell identity of the UE; match the obtained neighbor cell identity of the UE with the pre-stored neighbor cell identity of each sector of the cell where the UE is located. If the zone identifiers are the same, it is determined that the UE is in the sector, and the UE is located in the sector.

In step A, the method for determining the cell where the UE is located is: the RNC inquires whether there is measurement information of the UE locally, if not, the RNC initiates paging to the UE, and determines the cell where the UE is located according to the paging transfer success message; If yes, the cell where the UE is located is determined according to the measurement information of the UE stored in the RNC.

In step C, before determining the neighbor cell identity of the UE according to the measurement information, the method further includes: the RNC inquires whether there is UE measurement information locally, if not, the RNC initiates paging to the UE, and according to the paging information The transfer success message determines the cell where the UE is located; if there is, the cell where the UE is located is determined according to the measurement information of the UE stored in the RNC.

The measurement information includes status measurement information and distance measurement information obtained after paging;

After the RNC queries the measurement information of the UE not stored locally, and the RNC initiates paging to the UE, the method further includes: the RNC initiates distance measurement to the UE to determine the distance between the UE and the NodeB antenna;

In step B, the method of locating the UE behind the cell further includes: determining that the UE is in the cell according to the pre-stored cell information of the UE and the distance between the UE and the NodeB antenna obtained from the distance measurement s position;

In step C, the positioning UE is behind the sector, and the method further includes: determining that the UE is located in the sector according to the distance between the UE and the NodeB antenna obtained from the pre-stored sector information and the distance measurement. position in .

The method for determining the position of the UE in the cell according to the pre-stored information of the cell where the UE is located and the distance between the UE and the NodeB antenna is as follows:

According to the coordinates of the base station pre-stored in the RNC and the geometric shape of the cell where the UE is located, the position of the wireless terminal is determined to be on a circle or an arc whose radius is the distance from the UE to the NodeB antenna with the coordinates of the base station as the center.

The method for determining the position of the UE in the sector according to the prestored sector information and the distance between the UE and the NodeB antenna is as follows:

According to the coordinates of the NodeB pre-stored in the RNC and the geometry of the sector where the UE is located, the position of the wireless terminal is determined as: on a circular arc with the base station coordinates as the center and the distance from the UE to the NodeB antenna as the radius.

The distance measurement includes: round-trip travel time RTT measurement and Rx-Tx Type2 measurement;

The method for determining the distance between the UE and the NodeB antenna is: calculating the difference between the transmission time of the wireless signal in the air in the RTT measurement report and the processing time of the wireless signal by the UE in the Rx-Tx Type2 measurement report, and the obtained difference is the same as the two The quotient of , and the product of the obtained quotient value and the propagation speed of the pre-stored wireless signal in the air is used as the distance from the UE to the NodeB antenna.

It can be seen from the above technical solution that the method for realizing wireless terminal positioning in a multi-sector cell according to the present invention, through the measurement of the neighboring cells of the cell where the UE is located, compares the obtained neighbor cell ID of the cell where the UE is located with the pre-stored network side Match the neighbor cell identifiers of each sector of the cell where the UE is located, determine the sector where the UE is located, and then perform positioning according to the sector parameters. This method narrows the positioning range and improves the positioning accuracy.

Description of drawings

FIG. 1 is a schematic diagram of a network corresponding to multiple sectors in one cell;

Fig. 2 is the flowchart of the radio terminal positioning method under the CELL_ID+RTT positioning mode in the prior art multi-sector cell;

Fig. 3 is a schematic diagram of a network according to an embodiment of the present invention;

Fig. 4 is the flowchart of the wireless terminal positioning method under the CELL_ID+RTT positioning mode in the multi-sector cell of the present invention;

Fig. 5 is a flowchart of a wireless terminal positioning method in a CELL_ID positioning mode in a multi-sector cell according to the present invention.

Detailed ways

The core idea of the present invention is: according to the neighbor cell measurement report of the UE's cell, the RNC matches the neighbor cell ID in the neighbor cell measurement report with the neighbor cell ID of each sector of the UE's cell pre-stored on the network side, and judges the UE's location. The sector at the location is located, and then the positioning is performed according to the parameters of the sector, which reduces the positioning range and improves the positioning accuracy.

In order to make the object, technical solution and advantages of the present invention clearer, the present invention will be further described in detail below with reference to the accompanying drawings and preferred embodiments.

Fig. 3 is a schematic diagram of a network according to an embodiment of the present invention. In the network shown in Fig. 3, a logical cell 1 in the base station 1 includes two sectors, sector A and sector B; there is an omnidirectional cell 5 in the base station 2 , cell 5 is a neighboring cell of sector A of cell 1; there is also an omnidirectional cell 6 in base station 3, and cell 6 is a neighboring cell of sector B of cell 1. The relationship information between these cells, and the information parameters of each cell, such as whether the cell is a multi-sector cell, the identity of the cell, etc., have been stored in the network side database during network construction. The following describes in detail the methods for positioning a wireless terminal in a multi-sector cell in a CELL_ID-based positioning manner and a CELL_ID+RTT-based positioning manner in conjunction with FIG. 3 .

Embodiment 1: In the CELL_ID+RTT positioning mode, a wireless terminal positioning method in a multi-sector cell.

Figure 4 is a flow chart of the wireless terminal positioning method in the CELL_ID+RTT positioning mode in a multi-sector cell according to the present invention, assuming that the CN initiates a positioning UE request to the RNC, combined with the network structure shown in Figure 3, assuming that the UE is located in the sector of cell 1 In A, the specific working steps of the present invention are as follows:

Step 400: Determine the cell where the UE is located and the distance between the UE and the NodeB.

This step is completely consistent with steps 200 to 201 in the prior art, and will not be repeated here. Through measurement, in this embodiment, it can be concluded that the UE is located in cell 1, and it is assumed that the distance between the UE and the NodeB antenna is d.

Step 401: Determine whether the cell where the UE is located is multi-sector, if yes, go to step 402; otherwise, go to step 407.

In this step, according to the cell information pre-stored in the RNC, it is judged whether the cell 1 where the UE is located obtained in step 400 is a multi-sector cell. The judgment result in this embodiment is that cell 1 is a multi-sector cell.

Steps 402 to 403: Determine whether the RNC has UE measurement information including status measurement and distance measurement results. If not, the RNC initiates paging and distance measurement to the UE and proceeds to step 404; if yes, proceeds to step 404.

In this step, there are steps 402 and 403 because the UE may enter the idle state again before entering step 404 .

The RNC initiates paging for the UE, completes the state transition of the UE, and makes the UE transfer from an idle state, such as URA_PCH state or IDLE state, to an active state, such as Cell_DCH state or Cell_FACH state. After the UE completes the state transfer, it will report a successful transfer message to the RNC. The successful transfer message comes from the cell where the UE is located, so the RNC can determine the cell where the UE is located according to the successful transfer message;

After that, the RNC sends an RTT measurement request to the NodeB, sends a Rx-Tx Type2 measurement request to the UE, and calculates the signal _transmission time T from the UE to the RNC according to the RTT measurement report and the Rx-Tx Type2 measurement report;

Finally, according to the _calculated T and the pre-stored wireless signal propagation speed v in the air, calculate the distance d from the UE to the NodeB antenna. The distance d=T _xv .

The paging and measuring method and process in this step are completely consistent with the prior art.

Steps 404 to 405: Query the UE measurement information, obtain the neighbor cell ID, and match the obtained neighbor cell ID with the pre-stored neighbor cell IDs of each sector of the cell where the UE is located, and finally determine the sector where the UE is located according to the matching result .

In this step, it can be obtained from the measurement information that the neighbor cell of the UE is cell 5, and the RNC extracts the identity of cell 5 from the measurement information to match the pre-stored neighbor cell identity of each sector of cell 1 where the UE is located. It can be seen from Figure 3 that cell 1 The neighbor cell of sector A is cell 5. Through matching, it can be concluded that the ID of the neighbor cell of sector A is the same as the ID of cell 5 in the measurement report, so it can be concluded that the UE is located in sector A of cell 1.

Step 406: Obtain the information of the sector where the UE is located.

In this step, the RNC calls out the pre-stored parameters of the sector A of the cell 1 from the database, such as the geometric shape of the sector, the opening direction of the sector, and the like.

Step 407: Obtain the information of the cell where the UE is located.

In this step, the RNC calls out the pre-stored parameters of the cell 1 from the database, such as the geometric shape of the cell 1, whether the cell 1 is omnidirectional or fan-shaped, and if it is fan-shaped, the direction of the fan-shaped opening, etc.

Step 408: The RNC determines and reports the UE positioning result.

In this step, the RNC performs positioning according to the pre-stored NodeB coordinates and the parameters of the cell or sector where the UE is located: if the cell is a single sector, the final positioning result is a circle or circle with the NodeB as the center and the distance d as the radius On the arc; if the cell is multi-sector, the final positioning result is on a circular arc of a certain sector of the cell with the NodeB as the center and the distance d as the radius.

In this embodiment, the final positioning result of the UE is that the UE is located on a circular arc in sector A of the cell 1 with the NodeB as the center and the distance d as the radius.

From the method of the present invention, it is not difficult to see that in the CELL_ID+RTT positioning mode, when the UE is located in a multi-sector cell, the final positioning result is narrower than the positioning range of the existing method, which improves the positioning accuracy of the UE.

Embodiment 2: In the CELL_ID positioning mode, a wireless terminal positioning method in a multi-sector cell.

Figure 5 is a flow chart of the wireless terminal positioning method in the CELL_ID5 positioning mode in the multi-sector cell of the present invention, assuming that the CN initiates a positioning UE request to the RNC, combined with the network structure shown in Figure 3, assuming that the UE is located in sector A of cell 1 , the concrete working steps of the present invention are as follows:

Step 500: Determine the cell where the UE is located.

This step is completely consistent with step 200 in the prior art, and will not be repeated here. In this embodiment, it can be concluded that the UE is located in cell 1.

Step 501: Determine whether the cell where the UE is located is multi-sector, if yes, go to step 502; otherwise, go to step 507.

In this step, according to the cell information pre-stored in the RNC, it is judged whether the cell 1 where the UE is located obtained in step 500 is a multi-sector cell. The judgment result in this embodiment is that cell 1 is a multi-sector cell.

Step 502-Step 503: Determine whether the RNC has the measurement report information of the UE, if not, the RNC initiates paging to the UE and proceeds to step 504; if yes, proceeds to step 504.

In this step, there are steps 502 and 503 because the UE may enter the idle state again before entering step 504 . The paging method and process in this step are completely consistent with the process in step 200 and will not be described again.

Steps 504 to 505: Query the UE measurement report, obtain the neighbor cell ID, and match the obtained neighbor cell ID with the pre-stored neighbor cell IDs of each sector of the cell where the UE is located, and finally determine the sector where the UE is located according to the matching result .

In this step, it can be obtained from the measurement report that the neighbor cell of the UE is cell 5, and the RNC extracts the identifier of cell 5 from the measurement report to match the pre-stored neighbor cell identifiers of each sector of cell 1 where the UE is located. It can be seen from Figure 3 that cell 1 The neighbor cell of sector A is cell 5. Through matching, it can be concluded that the ID of the neighbor cell of sector A is the same as the ID of cell 5 in the measurement report, so it can be concluded that the UE is located in sector A of cell 1.

Step 506: Obtain the information of the sector where the UE is located.

In this step, the RNC calls out the pre-stored parameters of the sector A of the cell 1 from the database, such as the geometric shape of the sector, the opening direction of the sector, and the like.

Step 507: Obtain the information of the cell where the UE is located.

In this step, the RNC calls out the pre-stored parameters of the cell 1 from the database, such as the geometric shape of the cell 1, whether the cell 1 is omnidirectional or fan-shaped, and if it is fan-shaped, the direction of the fan-shaped opening, etc.

Step 508: RNC determines and reports the UE positioning result.

In this step, the RNC performs positioning according to the pre-stored NodeB coordinates and the parameters of the cell or sector where the UE is located: if the cell is a single sector, the final positioning result is that the UE is located in this cell; if the cell is multi-sector, then The final positioning result is that the UE is located in a certain sector of the cell.

In this embodiment, the final positioning result of the UE is that the UE is located in sector A of cell 1 .

From the method of the present invention, it is not difficult to see that in the CELL_ID positioning mode, when the UE is located in a multi-sector cell, the final positioning result is narrower than the positioning range of the existing method, and the positioning accuracy of the UE is improved.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the protection scope of the present invention.

Claims (8)

1. A method for realizing wireless terminal UE positioning in a multi-sector cell, is characterized in that the method comprises the following steps: A. The radio network controller RNC determines the cell where the UE is located; B. According to the pre-stored cell information, the RNC judges whether the cell where the UE is located is a multi-sector cell, if not, locates the UE in the cell; if so, enters step C; C. According to the measurement information, determine the neighbor cell identity of the UE; match the obtained neighbor cell identity of the UE with the pre-stored neighbor cell identity of each sector of the cell where the UE is located. If the zone identifiers are the same, it is determined that the UE is in the sector, and the UE is located in the sector. 2. The method according to claim 1, wherein in step A, the method for determining the cell where the UE is located is: the RNC inquires whether there is UE measurement information locally, if not, the RNC initiates a search to the UE and determine the cell where the UE is located according to the paging transfer success message; if so, determine the cell where the UE is located according to the measurement information of the UE stored in the RNC. 3. The method according to claim 1, wherein in step C, before determining the neighbor cell identity of the UE according to the measurement information, the method further comprises: the RNC inquires whether there is measurement information of the UE locally, if If not, the RNC initiates paging to the UE, and determines the cell where the UE is located according to the paging transfer success message; if yes, determines the cell where the UE is located according to the measurement information of the UE stored in the RNC. 4. The method according to claim 2 or 3, wherein the measurement information comprises state measurement information obtained after paging. 5. The method according to claim 2 or 3, wherein the measurement information comprises state measurement information and distance measurement information obtained after paging; After the RNC queries the measurement information of the UE not stored locally, and the RNC initiates paging to the UE, the method further includes: the RNC initiates distance measurement to the UE to determine the distance between the UE and the NodeB antenna; In step B, the method of locating the UE behind the cell further includes: determining that the UE is in the cell according to the pre-stored cell information of the UE and the distance between the UE and the NodeB antenna obtained from the distance measurement s position; In step C, the positioning UE is behind the sector, and the method further includes: determining that the UE is located in the sector according to the distance between the UE and the NodeB antenna obtained from the pre-stored sector information and the distance measurement. position in . 6. The method according to claim 5, wherein the method for determining the position of the UE in the cell according to the prestored information about the cell where the UE is located and the distance between the UE and the NodeB antenna is: According to the coordinates of the base station pre-stored in the RNC and the geometric shape of the cell where the UE is located, the position of the wireless terminal is determined to be on a circle or an arc whose radius is the distance from the UE to the NodeB antenna with the coordinates of the base station as the center. 7. The method according to claim 5, wherein the method for determining the position of the UE in the sector according to the prestored sector information and the distance between the UE and the NodeB antenna is: According to the coordinates of the NodeB pre-stored in the RNC and the geometry of the sector where the UE is located, the position of the wireless terminal is determined as: on a circular arc with the base station coordinates as the center and the distance from the UE to the NodeB antenna as the radius. 8. The method according to claim 5, wherein the distance measurement comprises: round-trip travel time RTT measurement and Rx-Tx Type2 measurement; The method for determining the distance between the UE and the NodeB antenna is: calculating the difference between the transmission time of the wireless signal in the air in the RTT measurement report and the processing time of the wireless signal by the UE in the Rx-Tx Type2 measurement report, and the obtained difference is the same as the two The quotient of , and the product of the obtained quotient value and the propagation speed of the pre-stored wireless signal in the air is used as the distance from the UE to the NodeB antenna.

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