RU2255433C2 - Method and system for quality-based location of site - Google Patents

Abstract

FIELD: location of wireless terminal in cellular communication network.

SUBSTANCE: novelty is that request on location includes information about quality for determining desired quality of location service quality, checkup of information about quality in location request transmission channel of cellular communication network, and selection of network component to be used for locating wireless terminal basing on requirement to quality indicated by means of information about quality, network component being chosen out of base network and cellular communications radio access network components in which location can be found.

EFFECT: enhanced throughput capacity of network concerning location requests.

14 cl, 4 dwg

Description

FIELD OF THE INVENTION

The present invention relates to a method and system for determining location, which are designed to determine the location of a wireless terminal in a cellular communication network.

State of the art

Positioning systems use one or more positioning technologies to determine the location of a terminal such as a mobile station, subscriber unit, or any other type of radio terminal. Positioning a given terminal includes measuring the signal and calculating a location estimate from the measured signals. An assessment of location or positioning usually gives the geographical location of the mobile station and / or existing mobile communications equipment in the form of latitude and longitude data. The location estimate can be presented in a given universal format.

Positioning technology for positioning systems (COM, LCS) as part of a cellular communication network of a global mobile communication system (GSM) can be implemented based on a method with determining the time of arrival (ORP) of an uplink signal, methods with determining the time difference (ODS, OTD) of the arrival of the signal (for example, ARIA, OTDOA or the method of high-precision OTD (B-ODS, E-OTD)), a method that uses global positioning system (GPS), a method for identifying cells (ID, CI), requests for registering the location of the subscriber from ti (Romas, HLR) or register positioning visitor network (ROMVS, VLR) or any combination of these methods. As a backup procedure to support any of the mentioned positioning technologies, except for positioning using ROMAS / ROMVS (HLR / VLR) (registering the location of the network subscriber or registering the location of the network visitor), the synchronization advance parameter (OS, TA) can be applied. The OS value is usually known for the serving base transceiver station, which provides an OS value for a given mobile station in standby mode. A special call that the user or subscriber of the mobile station does not notify is established using the search call (paging) procedure, for example, not a real call, and in response to this call, the cell number (CI) (cell identifier) of the serving cell and the OS are transmitted.

In GSM, in accordance with the positioning method on the ORP of an uplink signal, the arrival time of a known signal transmitted by a mobile station and received by at least three measuring modules is measured. A known signal is an access data packet generated by an asynchronous handoff performed by a mobile station. In order to accurately measure the time of arrival of data packets, the method requires the installation of additional equipment constituting the measuring module on the network, in the geographical vicinity of the mobile station, i.e. position measurement module (MIM, LMU). Since the geographical coordinates of the measuring modules are known, the position of the mobile station can be calculated in the main center of position calculations by the method of hyperbolic triangulation.

In addition, the B-ODS method is based on measurements of a high-precision difference in the arrival times of data packets of neighboring pairs of base transceiver stations (BTS, BTS) performed by a mobile station. To ensure accurate triangulation, B-ODS measurements must be performed for at least three different pairs of geographically dispersed BTSs. The location of the mobile station can be calculated from the measured values of B-ODS either in the network or in the mobile station itself, if the mobile station has all the necessary information.

The method based on GPS means involves any of several options in which GPS signals or additional signals obtained from GPS signals are used to calculate the coordinates of the mobile station.

The positioning system is logically implemented in a cellular communication network using an additional network node: the location center of mobile terminals (COMMT, MLC). In particular, they will equip the gateway center for determining the location of mobile terminals (МЦОММТ, GMLC), which is the first node in a cellular network to which an external client accesses. The mobile terminal location network gateway center (MCOMMT) requests routing information from the network subscriber location register (ROMAS), authorizes registration, transmits a positioning request to the network, and receives location estimates from the network. In addition, a service center for determining the location of mobile terminals (OCOMMT, SMLC) is equipped, which controls the overall coordination and scheduling of the resources necessary to perform positioning or positioning of a mobile or wireless terminal. This center also calculates the final location estimate and its accuracy. One cellular network may contain several OTsOMMT and ITSOMT.

The so-called OCOMMT based on the navigation satellite service (NSS, NSS) supports the positioning of a given mobile station by transmitting a signal to a freely accessible switching center of mobile terminals (CCMT, MSC), and the so-called OCOMMT based on the broadcasting-satellite service (RCC, BSS) supports positioning by transmitting a signal to a base station controller (BSC, BSC) serving a given mobile station. Both types of OCOMMTs can support a communication interface to provide access to information held by another OCOMMT.

OTSOMMT manages the MIM group to obtain measurement data via the radio channel interface to determine or support the location of mobile station subscribers in the area served by this center. The signals exchanged by the OCMMT based on the NCC and MIM are transmitted through the CCMT serving the MIM, and the signals exchanged by the OCOMMT based on the RCC and the MIM are transmitted through the BSC controller, which serves the MIM or controls them. The functions of the OCOMMT and the MCOMMT can be combined into one physical node from among existing physical nodes or distributed across different nodes of a cellular network.

A more detailed description of known positioning systems is given in the technical description of GSM 03.71.

EP 0905992 A1 describes a location procedure when location requests are transmitted to mobile terminals. The decision module in the composition of the mobile terminals is configured to measure the quality level of the received radio signals and enable a special positioning function when the measured quality level falls below the set level. Therefore, the positioning procedure depends on the quality of the received radio signals and allows to achieve a high probability of successful execution.

In the aforementioned conventional location systems, each location request places a heavy burden on network functions related to signaling, location calculation and measurement. Therefore, to organize a positioning system (COM, LCS) in a network, sufficient bandwidth for signal transmission and centralized computing and / or measuring power should be provided. However, COM with known configurations is no longer able to process the required number of location requests per second in accordance with the requirements of the operator.

SUMMARY OF THE INVENTION

For this reason, it is an object of the present invention to provide a method and system for determining location by which it is possible to increase network throughput by location requests.

This problem is solved by a method for determining the location of a wireless terminal in a cellular network in response to a location request, namely that quality information is included in the location request, and the quality information determines the required service quality, quality information is controlled in the request transmission channel locations in the cellular network, and based on the quality information, a network element is selected in which the location of the wireless terminal should be determined.

Although the quality requirements are already taken into account in well-known location procedures, they are used only when choosing local methods. In practice, this means that the parameter of service quality (QoS, QoS) is used only in the configurations of the BSS and the NSS to select the applicable method. In contrast to the above, in accordance with the present invention, the method selection logic can be distributed throughout the network, namely, MCOMMT (positioning based on the ROMAS / ROMVS zones), CCMT (positioning based on KBS), KBS (positioning according to IN, a, in addition, in some cases using B-ODS technology and using GPS means) and mobile stations (MS, MS) (positioning based on MS using B-ODS technology and using GPS means). With this approach, the calculation can be performed by a device that is optimal in terms of the required accuracy and the use of network resources.

In addition, the aforementioned problem is solved by using a network element for sending a location request to a critical network element that determines the requested location of the wireless terminal, containing

control means for monitoring quality information included in the location request, the quality information determining the required quality of service and

selection means for selecting a critical network element based on quality information.

In addition, the aforementioned task is solved by a system for determining the location of a wireless terminal in a cellular communication network in response to a location request containing service functional means for including quality information in the location request and a network element for selection based on the network element quality information in which determines the location of the wireless terminal, and to send a location request to the selected network element, and the selected network element is made with possible the ability to receive a location request and determine a location in response to a location request.

In accordance with the present invention, the known centralized location configuration is improved by distributing the processing power of the positioning system. In addition, the transmission of location requests can be interrupted at the earliest possible stage in accordance with the quality of service (CS) required by the location service. Location data can be computed at multiple locations or network elements and need not always be routed to a radio access network. Thus, the signaling load is reduced, since some location requests may be serviced at a network point closer to their source, and they need not be routed along the entire route to the radio access network. The distribution of computing means reduces the computing load on the network element in question.

In a preferred embodiment, the desired quality of service is used when selecting a location method determined based on the accuracy and / or response time indicated by the quality of service. Thus, location requests with a low accuracy requirement and / or fast response requirement need not be sent to the end to the radio access network, but can be processed already in the core network.

If the quality information involves fast response time and low accuracy, the location of the wireless terminal can be determined in the network element of the core network. In particular, the MCOMMT center or the CCMT center may be a network element that can determine the location by a cell identifier. At the same time, the location can be determined using the CAMEL function (special applications for the extended logic of the mobile communication network) or location information received from a ROMAS or ROMBC request.

Advantageous modifications or further embodiments of the invention are set forth in the dependent claims.

Brief Description of the Drawings

The following is a detailed description of the present invention as an example of a preferred embodiment with reference to the accompanying drawings, in which:

Figure 1 is a block diagram of a conventional positioning system in which all location requests are routed to a radio access network;

2 is a diagram depicting various location methods with their response times and accuracy;

Figure 3 is a block diagram of a positioning system in accordance with a preferred embodiment of the invention;

4 is a flowchart of a location request processing in accordance with a preferred embodiment of the invention.

Description of a preferred embodiment of the invention

The following is a description of a preferred embodiment of the invention using an example of a COM configuration in which location requests are forwarded from a COM client 40 to the IOMCMT 30 of the core network in question.

Figure 1 shows COM in a traditional configuration in which all location requests received from an external COM client 40 are sent using MCOMMT 30 through a core network element 20, for example, a second or third generation CCMT as part of a core network based on GSM, or a service node for support of general packet radio services (GCS, SGSN) of the second or third generation as part of a core network built on the basis of the public packet radio services (GPRS) system, to the radio access network (RAN) 10, content living OCOMMT. The WDS 10 may be a GPRS (GERAN) standard or a UMTS (Universal Mobile Telecommunications System) standard (UTRAN) ground control system. The routing performed by MCOMMT 30 may be based on a query of the internal subscriber database, for example, the internal subscriber server (BAC, HSS) 50. Thus, as shown in FIG. 1, the location calculation function is implemented centrally in the DRS 10.

However, it is very likely that most of the location services requested by the external COM 40 client can be performed with limited accuracy (for example, the method based on the ID), and only a few services need to use more accurate methods that require operations in the corresponding mobile terminal 1 or in the DRS 10. Therefore, in accordance with a preferred embodiment of the invention, the load necessary for determining the location can be distributed in accordance with the quality of service required location determination. In order to achieve this, quality information is attached to the location request message of the mobile terminal. Quality information can be included or embedded in the location request message from the 40 COM client. The quality information may establish or indicate the desired CS and may be used to select the appropriate or most suitable method for determining the location and, therefore, the place where the location should be determined or calculated.

FIG. 2 is a diagram depicting various location methods with their response times and accuracy. In addition, the arrow indicates where in the network the appropriate method can be implemented. In accordance with FIG. 2, GPS-based positioning or positioning methods are implemented in the mobile terminal 1 (or BSC / radio network controller (RNC)), and ODS methods are implemented in the base station controller (BSC) (or mobile terminal) SRD 10. Methods based on IN can be implemented in KBS / KSR, TsKMT or OUPUP of a basic network 20 or in MTsOMMT 30. Positioning on the basis of the ROMVS / ROMAS zones can be carried out in the center MTsOMMT. In addition, as can be seen from figure 2, high-precision location determination (i.e., with an accuracy better than about 100 m) should be performed in the DRS 10 when a longer required response time is assigned until the result is obtained. On the other hand, positioning with low accuracy (i.e., with accuracy worse than about 100 m) can be performed in the core network, and response time can be reduced.

Thus, it is possible to make a decision on where to process location requests in the MCOMMT 30 or other suitable switching element of the core network in order to send only such location requests that provide the corresponding level of CS, to the DRS 10, i.e. high accuracy and / or long response time. Therefore, it is possible to process and calculate some location requests already in the ILCMMT 30 or in the CCMT, or in the OUPUP of the core network 20.

In accordance with a preferred embodiment of the invention, it is possible to formulate the following model of load distribution depending on the required level of KU:

Requirement for KU level A type “fast response time, low accuracy”:

If the quality information added to the location request indicates the above requirement, then methods based on the ID or the POMC / POMAC zones are most suitable. Therefore, the calculation can be performed or started in the MCOMMT 30 or in a system with a configuration based on the NSS (i.e., in CCMT or OUPUP of the core network 20). The necessary location information may be requested by the CAMEL function (special applications for extended mobile network logic) (e.g. ATI) or by any other suitable means.

The requirement for the level of KU type B is “high accuracy, long response time”:

If the location request contains the above quality information, then more advanced positioning methods are required. Therefore, the location request is sent to the DRS 10, where the necessary measurements and calculations begin.

Most of the location requests will likely include a requirement for the level of the type A control unit, which means that most of the calculations for determining the location will be performed or started at the ILCMMT 30. This allows you to partially remove the burden associated with calculations and signal transmission from the SRDS 10.

Figure 3 is a schematic diagram of a COM in accordance with a preferred embodiment of the invention. COM requests coming from the COM client 40 are sent to the ICOMMT 30 center. The COM client 40 can include a COM combined with at least one client that can provide location-related services through the use of location information. Typically, the COM client 40 is a logical functional entity that requests location information with a predetermined set of parameters, for example, the QoS level, for at least one desired mobile terminal or mobile station. COM client 40 may be part of an object within a cellular network or as part of an external entity with respect to a cellular network. The COM client 40 is configured to add, enable, or attach quality information that indicates the desired level of QoS and transmits a location request to the MCOMMT 30. Then, the control function of the MCOMMT 30 extracts and checks the quality information to determine a suitable location for determining the location. Based on the result of this control operation, the selection tool provided in the ILCMMT 30 selects a suitable location for performing location determination operations. This choice may also be the choice of one of two networks of the second or third generation (2G / 3G).

Figure 4 is a sequence diagram of the implementation of the control and selection functions in MCOMMT 30. After the location request is received in step S100, it is transmitted to the control function, which determines the type of the required level of control unit in step S101. Based on the indicated KU level, for example, the KU level of type A or type B, the procedure branches out in step S102. If the level of KU type A is detected, the procedure proceeds to step S103, where the calculation or determination of the location in the MCOMMT 30 begins, for example, by sending a location request to the location server 60, which provides the information necessary for implementing the positioning method based on the ID ( or ROMVS / ROMAS zones). On the other hand, if the level of the KU type B is detected, the procedure proceeds to step S104, where the location request is sent by the MCOMMT 30 to the WDS 10 to determine the location more accurately.

It should be noted that the control or decisive function and the selection function can be implemented using the corresponding standard programs of the control program that controls the processor provided in the MCOMMT 30, or can be implemented in the form of corresponding discrete hardware functions of the MCOMMT 30.

Since most COM requests are interrupted at the earliest possible stage, the load on other elements of the communication network is reduced. In addition, the computational load is so distributed over the network that the computational load on the network element in question is also reduced.

In the case of dual-mode terminals, restrictions are imposed on the simultaneous use of the GSM system and WCDMA / GPRS networks (wideband code division multiple access communication system (CMDKR) / public packet radio communication system) or other means. In practice, this means that connections to WCDMA / GPRS networks are temporarily terminated if the location or call of the mobile terminal is carried out in the GSM system. Therefore, quality-based monitoring and assignment in accordance with the proposed invention can be carried out to make decisions about choosing either a local location or positioning method, for example, location based on an ID in a WCDMA standard network, or an improved location method by another system terminal.

In particular, MCOMMT 30 may receive a location request from COM client 40. This request includes, for example, the subscriber number of the user whose location you want to determine, and the required level KU. The level of KU is stored in ICMMT 30 for subsequent use. Then MCOMMT 30 sends a request to the internal subscriber database 50, for example to ROMAS, to determine the appropriate network and element of the core network that serve the subscriber. МЦОММТ 30 can receive a response from the internal subscriber database 50, which shows that the subscriber maintains an active connection to some network that does not belong to the GSM system (for example, a network of WCDMA standard). In addition, the terminal is connected to the GSM network. Firstly, “local” positioning methods are used, for example, a location request is sent to the core network in which the terminal operates. For example, MCOMMT 30 may transmit a location request to a third generation (3G) core network. The core network uses an active overhead signaling channel to send a location request to a radio access network, for example, to a RRC (radio network controller). The considered element of the radio communication network performs operations related to COM, which can be built into it. It should be noted that these operations may or may not provide the requirements for the level of KU set in the location request. The location estimate is transmitted back to the core network with the COM parameters, which may include the coordinates of the terminal, ID, etc. In addition, the answer includes the achieved accuracy of the positioning assessment.

The core network transmits the assessment to the ILCMMT 30, which checks whether the requirement for the level of QI is met. If the requirement for the KU level is not fulfilled, then МЦОММТ 30 transmits the СОМ request to CCMT (mobile terminal switching center) of the GSM network, which forms a signal transmission channel to the terminal and sends the request to the serving BSC or OCOMMT. At the same time, the BSC or OCOMMT has an open channel for transmitting signals to the terminal and is therefore able to enable COM measurements. OCOMMT calculates a location using B-ODS, A-GPS technology (using GPS) or similar methods. The location estimate is sent back to the CCMT, which sends the new assessment to the ILCMT 30. The ILCM 30 sends the most suitable location estimate to the COM client 40.

Thus, in appropriate cases, improved methods for positioning or positioning in the GSM system may be provided. It should be noted that if the requirements for the level of control are fulfilled, the execution of the COM procedure can be stopped when the first location estimate is received from the “local” positioning system. However, if the requirement for the KU level is not fulfilled, then МЦОММТ 30 can use the capabilities of the GSM network to increase accuracy.

It should be noted that the present invention is applicable to COM of any configuration in which a location request is routed through centralized network elements to special location functional units. In addition, it should also be noted that quality information (QoS) is not necessarily included in the original location request received by the IOMCMT from the COM application. In this case, this MCOMMT may include quality information depending on a given dynamic load on the network and / or other specified parameters. Moreover, the backup procedure mentioned, reinforcing advanced positioning or positioning methods, can be performed in the case of any other network system and, therefore, does not imply limited use as a backup procedure for the GSM system. Therefore, the present invention is not limited to the preferred embodiment described above, and is subject to change within the scope of the invention defined by the claims below.

Claims (14)

1. The method of determining the location of the wireless terminal (1) in a cellular network in response to a location request, namely, that a) quality information is included in the location request, the quality information determining the required quality of the location service, b) quality information is monitored on a location request transmission channel in a cellular network and c) based on the quality requirement indicated by the quality information, select the network element used to determine the location of the wireless terminal (1), while the network element is selected from among those network elements of the core network and the radio access network of the cellular communication network in which positioning can be performed. 2. The method according to claim 1, characterized in that said required quality of service is used at the selection stage to obtain a positioning method for accuracy and / or response time indicated by said quality of service. 3. The method according to claim 1, characterized in that the location of the wireless terminal (1) is determined in the network element of the core network, if the quality information indicates that a quick response is required and low accuracy is acceptable. 4. The method according to claim 2, characterized in that the location of the wireless terminal (1) is determined in the network element of the core network, if the quality information indicates that a quick response is required and low accuracy is acceptable. 5. The method according to claim 4, characterized in that the network element is a gateway location center for mobile terminals (MCOMMT) (30) or a switching center for mobile terminals (CCMT), wherein said location is determined using a location method based on cell identification . 6. The method according to claim 5, characterized in that said location is determined using the CAMEL function (special applications for extended logic of the mobile communication network) or using location information obtained from a request from the network subscriber location register (ROMAS) or register determining the location of the visitor network (ROMVS). 7. The method according to any one of claims 1 to 6, characterized in that the request for the location of the wireless terminal (1) is sent to the radio access network (10) of the cellular communication network if the quality information indicates that high accuracy and an acceptable long response time are required. 8. A network element (30) for sending a location request to a critical network element that determines the requested location of the wireless terminal, comprising a) monitoring means for monitoring quality information included in the location request, the quality information determining the desired quality of the location service and b) a selection tool for selecting a critical network element based on a quality requirement indicated by quality information, wherein the critical network element is selected and of the network elements of the core network and radio access network of the cellular network in which the location determination may be performed. 9. The network element of claim 8, characterized in that it is the gateway center for determining the location of mobile terminals (IOMC) (30). 10. The network element according to claim 8, characterized in that the selection means is configured to select the decisive network element for determining in the ICMMT (30) or the switching center of mobile terminals (CCMT), if the quality information indicates that a quick response is required and low accuracy of said positioning is acceptable. 11. The network element according to claim 9, characterized in that the selection means is configured to select the decisive network element for determining in the MCOMMT (30) or the switching center of mobile terminals (CCMT), if the quality information indicates that a quick response is required and low accuracy of said positioning is acceptable. 12. A network element according to any one of claims 8 to 11, characterized in that the selection means is configured to select said decision network element for determining radio access in the network (10), if the quality information indicates that high accuracy is required and a permissible long duration response time. 13. A system for determining the location of a wireless terminal (1) in a cellular network in response to a location request, comprising a) service functionality (40) for including quality information in a location request, the quality information determining the desired quality of the location service, b) a network element (30) for selecting, based on the quality requirement indicated by the quality information, a network element (10, 60) in which the location of the wireless terminal (1) should be determined, and for sending a location request to the selected network element (10, 60), while the selected network element (10, 30) is selected from among those network elements of the core network and the radio access network of the cellular communication network in which location can be performed, c) whereby the network element (10, 60) is configured to receive a location request and determine said location in response to a location request. 14. The system according to item 13, wherein the network element is a gateway center for determining the location of mobile terminals (ICOMMT) (30), configured to select either server (60) for determining the location of the core network to which ICOMMT belongs (30), or a radio access network (10) serving the wireless terminal (1).

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