CN101316439B

Movatterモバイル変換

Info

Publication number: CN101316439B
Application number: CN2007101085204A
Authority: CN
Inventors: 小田恭弘; 沈纪恽; 山田武史
Original assignee: NTT Docomo Inc
Current assignee: NTT Docomo Inc
Priority date: 2007-05-31
Filing date: 2007-05-31
Publication date: 2012-06-27
Anticipated expiration: 2027-05-31
Also published as: CN101316439A

Abstract

本发明提供一种服务器装置、移动终端以及定位方式选择方法，其在单独用GPS无法实施定位的状况下从可利用的定位方式中选择误差小的定位方式。计算服务器(300)对接收来自GPS卫星的信号且与基站进行通信的移动终端(100)的位置进行估计。计算服务器(300)具备：定位信息解析部(302)，其根据蜂窝基站(200)和移动终端(100)之间的距离，选择使用小区/扇区定位或者混合定位中的任意一种定位方式；和位置检测部(303)，其使用由定位信息解析部(302)选择的定位方式，来计算移动终端(100)的位置。

The present invention provides a server device, a mobile terminal, and a positioning method selection method for selecting a positioning method with a small error from available positioning methods in a situation where GPS alone cannot be used for positioning. A calculation server (300) estimates the position of a mobile terminal (100) receiving signals from GPS satellites and communicating with a base station. The calculation server (300) has: a positioning information analysis unit (302), which selects any one of cell/sector positioning or hybrid positioning according to the distance between the cellular base station (200) and the mobile terminal (100) and a position detection unit (303) that calculates the position of the mobile terminal (100) using the positioning method selected by the positioning information analysis unit (302).

Description

Translated fromChinese

服务器装置、移动终端以及定位方式选择方法Server device, mobile terminal and positioning method selection method

技术领域technical field

本发明涉及从多个定位方式中选择一种定位方式的服务器装置、移动终端以及定位方式选择方法。The invention relates to a server device, a mobile terminal and a positioning method selection method for selecting a positioning method from multiple positioning methods.

背景技术Background technique

历来，公开了如下定位方法：在移动终端中内置GPS接收机，单独用来自GPS卫星的信号、或者用来自GPS卫星的信号和来自蜂窝基站的信号来确定终端位置(例如，参照专利文献1)。在室外的没有障碍物的环境，移动终端可以充分地接收来自GPS卫星的信号，在大部分场所都可以接收4个以上的来自GPS卫星的信号。Conventionally, a positioning method has been disclosed in which a mobile terminal has a built-in GPS receiver and uses signals from GPS satellites alone, or signals from GPS satellites and signals from cellular base stations to determine the position of the terminal (for example, refer to Patent Document 1) . In an outdoor environment without obstacles, the mobile terminal can fully receive signals from GPS satellites, and can receive more than 4 signals from GPS satellites in most places.

在使用了GPS的定位中，由于三维位置坐标X、Y、Z以及在终端的接收时刻为未知，因此需要接收来自至少4个GPS卫星的信号。即，若能从4个以上的GPS卫星接收信号，则可以仅用GPS来确定位置。In positioning using GPS, since the three-dimensional position coordinates X, Y, Z and the receiving time of the terminal are unknown, it is necessary to receive signals from at least four GPS satellites. That is, if signals can be received from four or more GPS satellites, the position can be determined using only GPS.

另外，由于移动终端用于各种场所，例如在大楼走廊或室内也使用移动终端。在这样的环境中，移动终端不能捕获来自GPS卫星的微弱电波(信号)，很多时候只能从不足4个的GPS卫星接收信号。这样若只能从不足4个的GPS卫星接收信号，则不能仅通过GPS卫星来测定移动终端的位置。In addition, since mobile terminals are used in various places, for example, mobile terminals are also used in corridors of buildings or indoors. In such an environment, the mobile terminal cannot capture weak radio waves (signals) from GPS satellites, and can only receive signals from less than four GPS satellites in many cases. In this way, if signals can only be received from less than four GPS satellites, the position of the mobile terminal cannot be measured only by the GPS satellites.

作为这种情况的对策，公开了如下混合(hybrid)定位方式，即使只能从不足4个的GPS卫星接收信号也可测定移动终端的位置。通过混合定位方式，该方法不是仅用GPS来进行位置计算，而是将蜂窝基站作为信号发送源之一来处理。As a countermeasure against such a situation, a hybrid positioning method is disclosed that can measure the position of a mobile terminal even if signals can only be received from less than four GPS satellites. Through the hybrid positioning method, the method does not only use GPS for position calculation, but handles the cellular base station as one of the signal transmission sources.

具体地，通过测定从蜂窝基站发送来的信号的接收定时，由此与GPS卫星同等地处理蜂窝基站，使信号源数不低于4。因此，从而在各种场所可以测定移动终端的位置。此外，作为特殊情况，即使在没有可从GPS卫星接收的信号的情况下，如果可接收4个以上的从基站发送的信号，则也可以通过同样的方法测定移动终端的位置。Specifically, by measuring the reception timing of a signal transmitted from a cellular base station, the cellular base station is treated on the same level as the GPS satellite so that the number of signal sources is not less than four. Therefore, the position of the mobile terminal can be measured in various places. In addition, as a special case, even if there are no signals that can be received from GPS satellites, if four or more signals transmitted from the base station can be received, the position of the mobile terminal can be measured by the same method.

在上述方法中，要求可接收的GPS以及蜂窝基站的信号源数量为4个以上。移动终端可接收的信号源数量因移动终端周围的状况而不同，也有信号源数未满4个的情况。In the above method, the number of receivable GPS and cellular base station signal sources is required to be four or more. The number of signal sources that can be received by a mobile terminal varies depending on the surrounding conditions of the mobile terminal, and the number of signal sources may be less than four.

作为这种情况的对策，公开有小区(cell)/扇区(sector)定位方式。具体地，将移动终端所在的蜂窝基站的位置计算为移动终端的位置。若蜂窝基站被扇区化，则可以使用该扇区的中心。此外，在可测定RTT(Round Trip Time)时，可以计算蜂窝基站～移动终端之间的距离，因此也可以用该距离和扇区信息来测定移动终端的位置。使用了小区/扇区定位方式的移动终端定位方法可以被用作在无法用GPS定位或混合定位的场所中的补充方法。若是移动终端的服务区(service area)，则是可以测定移动终端的位置的方法。As a countermeasure against this situation, a cell/sector positioning method is disclosed. Specifically, the location of the cellular base station where the mobile terminal is located is calculated as the location of the mobile terminal. If the cell site is sectorized, the center of the sector can be used. In addition, when the RTT (Round Trip Time) can be measured, the distance between the cell base station and the mobile terminal can be calculated, so the position of the mobile terminal can also be measured using the distance and sector information. The mobile terminal positioning method using the cell/sector positioning method can be used as a supplementary method in places where GPS positioning or hybrid positioning cannot be used. In the case of the service area of the mobile terminal, it is a method that can measure the position of the mobile terminal.

如上所述，移动终端的定位方式有多种方式，揭示了根据移动终端的使用环境来切换GPS定位、混合定位、或小区/扇区定位的方法(例如，参照非专利文献1)。As mentioned above, there are many ways of positioning a mobile terminal, and a method of switching GPS positioning, hybrid positioning, or cell/sector positioning according to the usage environment of the mobile terminal is disclosed (for example, refer to Non-Patent Document 1).

在非专利文献1中，根据可接收的信号源来判断定位方式的切换。具体地，如果信号源数量为4个以上则选择GPS定位或混合定位，如果不足4个则选择小区/扇区定位。InNon-Patent Document 1, the switching of the positioning method is judged according to the receivable signal source. Specifically, if the number of signal sources is more than 4, select GPS positioning or hybrid positioning, and if there are less than 4, select cell/sector positioning.

【专利文献1】特开2005-20216号公报[Patent Document 1] JP-A-2005-20216

【非专利文献1】“高精度测位ポジショニングシステムの応用とサ—ビス展開”シンポジウムテキストp.43-54平成18年3月3日機械振興会館地下2階ホ—ル主催：社团法人電子情報通信学会東京支部[Non-Patent Document 1] "High-precision Positioning Pojishioning System の応用とサービス Development" Symposium Tekistop p.43-54 March 3, 2018 Machine Promotion Hall Basement 2nd Floor Host: Incorporated Electronic Information Communication Society Tokyo Branch

发明内容Contents of the invention

小区/扇区定位的定位精度比GPS定位或混合定位精度差。因此，在移动终端可接收的信号源数量未满4时选择小区/扇区定位。The positioning accuracy of cell/sector positioning is worse than that of GPS positioning or hybrid positioning. Therefore, when the number of signal sources that the mobile terminal can receive is less than 4, cell/sector positioning is selected.

然而，当移动终端位于大楼走廊或室内等时，移动终端接收到来自蜂窝基站的信号时接收到的信号恶化，有时即使可接收的信号源数为4个以上，通过GPS定位或混合定位也不能得到充分的定位精度。However, when the mobile terminal is located in a corridor of a building or indoors, the signal received by the mobile terminal is degraded when it receives a signal from a cellular base station, and even if the number of signal sources that can be received is four or more, GPS positioning or hybrid positioning cannot Get sufficient positioning accuracy.

另一方面，位于小区(扇区)内的移动终端数量越多、即小区密度越高，则小区/扇区定位的定位精度就越高。也就是，小区半径和定位精度之间存在比例关系。因此，在小区半径小的城市，在大楼走廊或室内等使用混合定位时，与小区/扇区定位相比，定位精度有时更差。On the other hand, the greater the number of mobile terminals located in a cell (sector), that is, the higher the cell density, the higher the positioning accuracy of cell/sector positioning. That is, there is a proportional relationship between the cell radius and the positioning accuracy. Therefore, in cities with small cell radii, when hybrid positioning is used in building corridors or indoors, etc., the positioning accuracy is sometimes worse compared to cell/sector positioning.

因此，本发明鉴于以上问题而提出，其目的在于提供在单独用GPS无法测定移动终端位置的状况下从可利用的定位方式中适当地选择误差小的定位方式的服务器装置、移动终端以及定位方式选择方法。Therefore, the present invention is made in view of the above problems, and its object is to provide a server device, a mobile terminal, and a positioning method that appropriately selects a positioning method with a small error from available positioning methods in a situation where the position of the mobile terminal cannot be measured by GPS alone. Method of choosing.

为了达到上述目的，本发明的第一特征是，一种服务器装置，其对接收来自GPS卫星的信号且与基站进行通信的移动终端的位置进行估计，该服务器装置具有：(a)定位信息解析部，其根据基站与移动终端之间的距离，选择使用小区/扇区定位或者混合定位中的某一种定位方式；和(b)位置检测部，其使用由定位信息解析部选择的定位方式，计算移动终端的位置。In order to achieve the above object, the first feature of the present invention is a server device that estimates the position of a mobile terminal that receives a signal from a GPS satellite and communicates with a base station, the server device has: (a) positioning information analysis A part, which selects one of cell/sector positioning or hybrid positioning according to the distance between the base station and the mobile terminal; and (b) a position detection part, which uses the positioning method selected by the positioning information analysis part , to calculate the position of the mobile terminal.

根据第一特征的服务器装置，能够在单独用GPS无法实施定位的状况下从可利用的定位方式中，选择误差小的定位方式。According to the server device of the first aspect, it is possible to select a positioning method with a small error from available positioning methods in a situation where positioning cannot be performed by GPS alone.

另外，在第一特征的服务器装置中，也可以根据所述基站与所述移动终端之间的往返时间，确定距离。In addition, in the server device of the first aspect, the distance may be specified based on the round-trip time between the base station and the mobile terminal.

另外，第一特征的服务器装置的定位信息解析部也可以根据小区/扇区定位的估计误差和混合定位的估计误差计算出规定的阈值，将该规定的阈值和距离进行比较，在距离比规定阈值小的情况下，选择小区/扇区定位。In addition, the positioning information analysis unit of the server device according to the first feature may calculate a predetermined threshold value based on the estimated error of cell/sector positioning and the estimated error of mixed positioning, compare the predetermined threshold with the distance, and determine the difference between the distance ratio and the predetermined threshold. When the threshold is small, cell/sector positioning is selected.

本发明的第二特征是，一种移动终端，其接收来自GPS卫星的信号，并与基站进行通信，该移动终端具有：(a)定位信息解析部，其根据基站与移动终端之间的距离，选择使用小区/扇区定位或混合定位中的某一种定位方式；和(b)位置检测部，其使用由定位信息解析部选择的定位方式，计算移动终端的位置。The second feature of the present invention is a mobile terminal that receives signals from GPS satellites and communicates with a base station, the mobile terminal having: (a) a positioning information analysis unit that analyzes the distance between the base station and the mobile terminal; , selecting to use one of cell/sector positioning or hybrid positioning; and (b) a position detection unit, which uses the positioning mode selected by the positioning information analysis unit to calculate the position of the mobile terminal.

本发明的第三特征是，一种定位方式选择方法，其选择对接收来自GPS卫星的信号且与基站进行通信的移动终端的位置进行估计时使用的定位方式，该定位方式选择方法包括如下步骤：(a)根据基站与移动终端之间的距离，来选择使用小区/扇区定位或者混合定位中的某一种定位方式；(b)使用所选择的定位方式，计算移动终端的位置。The third feature of the present invention is a positioning method selection method for selecting a positioning method used when estimating the position of a mobile terminal that receives a signal from a GPS satellite and communicates with a base station, the positioning method selection method includes the following steps (a) according to the distance between the base station and the mobile terminal, choose to use a certain positioning method in cell/sector positioning or hybrid positioning; (b) use the selected positioning method to calculate the position of the mobile terminal.

根据本发明，可以提供能够在单独用GPS无法测定移动终端位置的状况下从可利用的定位方式中适当地选择误差小的定位方式的服务器装置、移动终端以及定位方式选择方法。According to the present invention, it is possible to provide a server device, a mobile terminal, and a positioning method selection method capable of appropriately selecting a positioning method with a small error from available positioning methods when the position of the mobile terminal cannot be measured by GPS alone.

附图说明Description of drawings

图1是本实施方式的通信系统的结构框图。FIG. 1 is a block diagram showing the configuration of a communication system according to this embodiment.

图2是表示本实施方式的定位方式的选择方法的流程图。FIG. 2 is a flowchart showing a method of selecting a positioning method according to this embodiment.

图3是用于说明本实施方式的扇区ID定位方式的图。FIG. 3 is a diagram for explaining a sector ID positioning method in this embodiment.

图4是表示本实施方式的小区/扇区定位的位置估计误差与通过混合定位得到的位置估计误差的模拟结果的曲线图。FIG. 4 is a graph showing simulation results of a position estimation error of cell/sector positioning and a position estimation error obtained by hybrid positioning according to the present embodiment.

图5是本实施方式的小区ID定位方式的说明图。FIG. 5 is an explanatory diagram of a cell ID positioning method according to this embodiment.

图6是本实施方式的RTT定位方式的说明图。FIG. 6 is an explanatory diagram of the RTT positioning method in this embodiment.

图7是变更例的通信系统的框结构图。FIG. 7 is a block configuration diagram of a communication system according to a modified example.

具体实施方式Detailed ways

下面，参照附图对本发明的实施方式进行说明。在以下附图的记载中，对于相同或类似的部分标注相同或类似的标号。其中，应注意的是附图是示意图。Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following description of the drawings, the same or similar reference numerals are attached to the same or similar parts. Wherein, it should be noted that the drawings are schematic diagrams.

(通信系统的结构)(Structure of Communication System)

本实施方式的通信系统具备：移动终端100，其接收来自GPS卫星的信号、且与蜂窝基站200进行通信；蜂窝基站200；以及计算服务器300，其对移动终端100的位置进行估计。The communication system of this embodiment includes:mobile terminal 100 that receives signals from GPS satellites and communicates withcellular base station 200 ;cellular base station 200 ; andcalculation server 300 that estimates the position ofmobile terminal 100 .

移动终端100接收来自GPS卫星的信号，并与蜂窝基站200进行通信。移动终端100具备GPS接收部101、蜂窝通信部102以及数据存储部103。Themobile terminal 100 receives signals from GPS satellites and communicates with thecellular base station 200 . Themobile terminal 100 includes aGPS receiving unit 101 , acellular communication unit 102 , and adata storage unit 103 .

GPS接收部101包括接收来自GPS卫星的信号的GPS天线、RF部、相关部和信号处理部。GPS接收部101使用在GPS天线接收到的信号中含有的GPS卫星信号序列的信息，来确定接收卫星的固有号码(以下称为“卫星ID”)。TheGPS receiving unit 101 includes a GPS antenna for receiving signals from GPS satellites, an RF unit, a correlation unit, and a signal processing unit. TheGPS receiving unit 101 specifies the unique number of the receiving satellite (hereinafter referred to as "satellite ID") using the information of the GPS satellite signal sequence included in the signal received by the GPS antenna.

GPS接收部101对于每一个可接收的GPS卫星，计算信号的接收定时以及接收时刻。之后，GPS接收部101向数据存储部103发送包含可接收信号的GPS卫星数、该卫星的卫星ID、接收定时以及接收时刻的GPS卫星信息。TheGPS receiving unit 101 calculates the signal reception timing and reception time for each receivable GPS satellite. Thereafter, theGPS receiving unit 101 transmits to thedata storage unit 103 GPS satellite information including the number of GPS satellites capable of receiving signals, the satellite ID of the satellite, the receiving timing, and the receiving time.

蜂窝通信部102通过接收蜂窝基站200发送的导频信号，决定进行通信的蜂窝基站和其扇区。这里，将所决定的蜂窝基站的扇区称为所在扇区。蜂窝通信部102向数据存储部103发送包含基站的固有号码(以下称为“基站ID”)和该基站ID的所在扇区的基站信息。Thecellular communication unit 102 receives the pilot signal transmitted from thecellular base station 200 to determine the cellular base station and its sector for communication. Here, the determined sector of the cellular base station is referred to as the existing sector. Thecellular communication unit 102 transmits the base station information including the unique number of the base station (hereinafter referred to as “base station ID”) and the sector where the base station ID is located to thedata storage unit 103 .

另外，蜂窝通信部102使用无线通信线路，经由蜂窝基站200向计算服务器300发送保存在数据存储部103中的GPS卫星信息以及基站信息。Also, thecellular communication unit 102 transmits the GPS satellite information and base station information stored in thedata storage unit 103 to thecalculation server 300 via thecellular base station 200 using a wireless communication line.

数据存储部103存储从GPS接收部101发送来的GPS卫星信息。另外，数据存储部103存储从蜂窝通信部102发送来的基站信息。Thedata storage unit 103 stores GPS satellite information transmitted from theGPS receiving unit 101 . Also, thedata storage unit 103 stores base station information transmitted from thecellular communication unit 102 .

蜂窝基站200与移动终端100进行通信。另外，蜂窝基站200从移动终端100接收GPS卫星信息和基站信息。蜂窝基站200通过网络发送给计算服务器300发送接收到的GPS卫星信息和基站信息。Thecellular base station 200 communicates with themobile terminal 100 . In addition, thecellular base station 200 receives GPS satellite information and base station information from themobile terminal 100 . Thecellular base station 200 sends the received GPS satellite information and base station information to thecomputing server 300 through the network.

蜂窝基站200测定基站～移动终端之间的往返时间(RTT)。蜂窝基站200从计算服务器300当接收到RTT测定的请求信号时，向移动终端100发送测定开始的请求信号。蜂窝基站200通过测定发送定时和接收定时来测定RTT。通过网络向计算服务器300发送RTT的测定结果。Thecellular base station 200 measures the round-trip time (RTT) between the base station and the mobile terminal. Thecellular base station 200 transmits a measurement start request signal to themobile terminal 100 upon receiving the RTT measurement request signal from thecalculation server 300 . Thecellular base station 200 measures RTT by measuring transmission timing and reception timing. The RTT measurement result is sent to thecalculation server 300 via the network.

计算服务器300收集移动终端100的位置测定(计算)所需要的信息，计算移动终端100的位置。移动终端100将计算结果发送给移动终端100。计算服务器300具有服务器通信部301、定位信息解析部302以及位置检测部303。Thecalculation server 300 collects information necessary for measuring (calculating) the position of themobile terminal 100 and calculates the position of themobile terminal 100 . Themobile terminal 100 sends the calculation result to themobile terminal 100 . Thecalculation server 300 has aserver communication unit 301 , a positioninginformation analysis unit 302 , and aposition detection unit 303 .

服务器通信部301通过蜂窝基站200从移动终端100接收GPS卫星信息和基站信息。服务器通信部301将接收到的GPS卫星信息和基站信息发送给定位信息解析部302。另外，服务器通信部301从蜂窝基站200接收蜂窝基站200所测定的RTT信息。服务器通信部301将接收到的RTT信息发送给定位信息解析部302。Theserver communication unit 301 receives GPS satellite information and base station information from themobile terminal 100 via thecellular base station 200 . Theserver communication unit 301 sends the received GPS satellite information and base station information to the positioninginformation analysis unit 302 . Also, theserver communication unit 301 receives the RTT information measured by thecellular base station 200 from thecellular base station 200 . Theserver communication unit 301 transmits the received RTT information to the positioninginformation analysis unit 302 .

然后，服务器通信部301从位置检测部303接收移动终端100的位置计算结果。服务器通信部301通过蜂窝基站200将接收到的位置计算结果发送给移动终端100。Then, theserver communication unit 301 receives the position calculation result of the mobile terminal 100 from theposition detection unit 303 . Theserver communication unit 301 transmits the received position calculation result to themobile terminal 100 via thecellular base station 200 .

定位信息解析部302根据GPS卫星信息、基站信息和RTT测定结果来选择最佳定位方式。在本实施方式中，使用GPS定位、混合定位以及小区/扇区定位三种方式。The positioninginformation analysis unit 302 selects an optimal positioning method based on GPS satellite information, base station information, and RTT measurement results. In this embodiment, three modes of GPS positioning, hybrid positioning and cell/sector positioning are used.

定位信息解析部302对基于这三种定位方式的位置定位误差进行估计。为了进行该估计，使用可用于位置计算的GPS卫星数以及基站数、信号的接收定时和卫星以及基站的配置、所在扇区信息、以及RTT测定结果。关于该估计方法以及定位方式的选择方法，将在后面叙述。The positioninginformation analysis unit 302 estimates position positioning errors based on these three positioning methods. For this estimation, the number of GPS satellites and the number of base stations that can be used for position calculation, the timing of receiving signals, the arrangement of satellites and base stations, information on the sector where they are located, and RTT measurement results are used. The estimation method and the selection method of the positioning method will be described later.

位置检测部303使用在定位信息解析部302选择的定位方式进行移动终端100的位置计算，并将位置计算结果发送给服务器通信部301。Theposition detection unit 303 calculates the position of themobile terminal 100 using the positioning method selected by the positioninginformation analysis unit 302 , and sends the position calculation result to theserver communication unit 301 .

(定位方式选择方法)(positioning method selection method)

下面，使用图2对本实施方式的定位方式的选择方法进行说明。Next, a method of selecting a positioning method according to this embodiment will be described using FIG. 2 .

首先，计算服务器300的定位信息解析部302指示位置检测部303尝试利用GPS进行单独定位(S201)。然后，位置检测部303利用移动终端100可接收信号的、即可观测的GPS卫星数以及定位误差判定，判断可否进行GPS单独定位(S202)。First, the positioninginformation analyzing unit 302 of thecomputing server 300 instructs theposition detecting unit 303 to try individual positioning using GPS (S201). Then, theposition detection unit 303 judges whether GPS independent positioning is possible or not by using the number of GPS satellites that can be received by themobile terminal 100 , that is, the number of observable GPS satellites, and the positioning error judgment ( S202 ).

在步骤S202，在可进行GPS单独定位时，定位信息解析部302选择GPS定位作为定位方式。位置检测部303使用GPS定位进行移动终端100的位置计算，结束处理(S208)。In step S202, when independent GPS positioning is possible, the positioninginformation analysis unit 302 selects GPS positioning as the positioning method. Theposition detection unit 303 calculates the position of themobile terminal 100 using GPS positioning, and ends the process (S208).

另一方面，在步骤S202，在不能进行GPS单独定位时，位置检测部303通过服务器通信部301向蜂窝基站200委托RTT测定。蜂窝基站200测定RTT(S203)。On the other hand, in step S202, when GPS independent positioning cannot be performed, theposition detection unit 303 requests RTT measurement to thecellular base station 200 through theserver communication unit 301 . Thecellular base station 200 measures RTT (S203).

接着，定位信息解析部302从基站200接收基站信息(基站ID、扇区数)以及RTT测定结果(S204)。然后，定位信息解析部302根据基站ID、扇区数，按照后述的方法求出小区/扇区定位有效的阈值X(S205)。通过事先实施模拟求出RTT和定位误差(小区/扇区定位以及混合定位)的关系来决定阈值X。Next, the positioninginformation analysis unit 302 receives base station information (base station ID, number of sectors) and RTT measurement results from the base station 200 (S204). Then, the positioninginformation analysis unit 302 obtains the threshold X for effective cell/sector positioning based on the base station ID and the number of sectors in accordance with a method described later (S205). Threshold X is determined by performing simulation in advance to obtain the relationship between RTT and positioning error (cell/sector positioning and hybrid positioning).

定位信息解析部302对所测定的RTT和阈值X进行比较(S206)。在步骤S206中，在RTT比X小的情况下，定位信息解析部302选择小区/扇区定位。位置检测部303使用小区/扇区定位进行移动终端100的位置计算，并结束处理(S209)。The positioninginformation analysis unit 302 compares the measured RTT with the threshold X (S206). In step S206, when the RTT is smaller than X, the positioninginformation analysis unit 302 selects cell/sector positioning. Theposition detection unit 303 calculates the position of themobile terminal 100 using cell/sector positioning, and ends the process (S209).

另一方面，在步骤S206中，在RTT为X以上时，利用可观测的卫星数、可观测的基站数、以及定位误差判定，来判断可否进行混合定位(S207)。在步骤S207中，在可以进行混合定位时，定位信息解析部302选择混合定位。位置检测部303使用混合定位进行移动终端100的位置计算，并结束处理(S210)。On the other hand, in step S206, when the RTT is greater than or equal to X, it is judged whether or not to perform hybrid positioning using the number of observable satellites, the number of observable base stations, and positioning error judgment (S207). In step S207, when hybrid positioning is possible, the positioninginformation analysis unit 302 selects hybrid positioning. Theposition detection unit 303 calculates the position of themobile terminal 100 using hybrid positioning, and ends the process (S210).

另一方面，当在步骤S207中不能进行混合定位时，定位信息解析部302选择小区/扇区定位。位置检测部303使用小区/扇区定位进行移动终端100的位置计算，结束处理(S210)。On the other hand, when hybrid positioning cannot be performed in step S207, the positioninginformation analysis unit 302 selects cell/sector positioning. Theposition detection unit 303 calculates the position of themobile terminal 100 using cell/sector positioning, and ends the process (S210).

下面，说明步骤S205中的阈值X的计算方法的一例。在阈值X的计算中，计算出小区/扇区定位的估计误差和混合定位的估计误差，求出这些距离特性曲线的交点。Next, an example of a calculation method of the threshold X in step S205 will be described. In the calculation of the threshold X, the estimation error of cell/sector positioning and the estimation error of hybrid positioning are calculated, and the intersection point of these distance characteristic curves is obtained.

首先，对小区/扇区定位的位置估计误差E_sector的计算方法进行叙述。如图3所示，在小区/扇区定位中，求出移动终端100所在的扇区的重心位置并将其作为定位结果。接着，求出扇区内的所有点和扇区的重心位置的距离。由于该距离为在各点的估计误差。将各点的估计误差相加后除以扇区面积就得出扇区内的平均估计误差E_sector。First, the calculation method of the position estimation error E_sector for cell/sector positioning is described. As shown in FIG. 3 , in cell/sector positioning, the centroid position of the sector where themobile terminal 100 is located is obtained and used as the positioning result. Next, the distances between all the points in the sector and the position of the center of gravity of the sector are obtained. Since this distance is an estimation error at each point. The average estimation error E_sector in the sector is obtained by adding the estimation errors of each point and dividing by the sector area.

另一方面，如下计算出混合定位的估计误差。在混合定位中，利用根据来自GPS卫星的信号的接收定时计算出的GPS卫星～移动终端间的距离和根据蜂窝基站～移动终端间的RTT计算出的蜂窝基站～移动终端间的距离，进行3边测量。On the other hand, the estimation error of hybrid localization is calculated as follows. In the hybrid positioning, the distance between the GPS satellite and the mobile terminal calculated from the reception timing of the signal from the GPS satellite and the distance between the cell base station and the mobile terminal calculated from the RTT between the cell base station and the mobile terminal are used to perform 3 side measure.

这里，考虑到利用了2个GPS卫星和1个蜂窝基站～移动终端间的RTT的混合定位。若设GPS卫星～移动终端间的距离误差为σ_GPS1、σ_GPS2，设蜂窝基站～移动终端间的距离误差为σ_BS，则可以用式(1)表示混合定位中的位置估计误差E_Hybrid。Here, hybrid positioning using two GPS satellites and one RTT between a cellular base station and a mobile terminal is considered. If the distance error between the GPS satellite and the mobile terminal is σ_GPS1 and σ_GPS2, and the distance error between the cellular base station and the mobile terminal is σ_BS, the position estimation error E_Hybrid in hybrid positioning can be expressed by formula (1).

E_Hybrid＝{(σ_GPS1)²+(σ_GPS2)²+(σ_BS)²}1/2……式(1)E_Hybrid＝{(σ_GPS1)² +(σ_GPS2)² +(σ_BS)² }1/2...Formula (1)

关于σ_GPS1、σ_GPS2、σ_BS，可通过进行多次测定以使用其RMS(RootMean Square：均方根)。另外，也可以使用通过经验取得的值来估计σ_GPS1、σ_GPS2、σ_BS。Regarding σ_GPS1, σ_GPS2, and σ_BS, RMS (Root Mean Square: root mean square) can be used by performing multiple measurements. In addition, σ_GPS1, σ_GPS2, and σ_BS may be estimated using empirically acquired values.

图4表示小区/扇区定位中的位置估计误差E_sector和混合定位中的位置估计误差E_Hybrid的模拟结果的一例。如图4所示，可知E_sector和E_Hybrid具有交点。此时的阈值X就使用该交点的值。FIG. 4 shows an example of simulation results of a position estimation error E_sector in cell/sector positioning and a position estimation error E_Hybrid in hybrid positioning. As shown in Figure 4, it can be known that E_sector and E_Hybrid have an intersection. The threshold X at this time uses the value of the intersection point.

另外，在上述定位方式的选择方法中，作为小区/扇区定位，说明了使用扇区ID定位方式的情况，在该扇区ID定位方式中求出移动终端所在的扇区的重心位置并将该重心位置作为定位结果，而作为小区/扇区定位，也可以使用其他方式。In addition, in the selection method of the positioning method described above, as the cell/sector positioning, the case of using the sector ID positioning method is described. In this sector ID positioning method, the barycentric position of the sector where the mobile terminal is located is obtained and The position of the center of gravity is used as a positioning result and as a cell/sector positioning, and other methods may also be used.

例如，图5表示使用了小区ID定位方式的情况。在小区ID定位方式中，根据基站的纬度、经度、所在小区ID来计算出小区的中心坐标。即，将基站的坐标作为移动终端的位置来进行估计的方法。For example, FIG. 5 shows the case where the cell ID positioning method is used. In the cell ID positioning method, the center coordinates of the cell are calculated according to the latitude, longitude, and cell ID of the base station. That is, a method of estimating the coordinates of the base station as the position of the mobile terminal.

另外，图6表示使用了RTT定位方式的情况。RTT定位方式中，是将根据RTT计算出的圆和扇区中心线的交点作为移动终端的位置来进行估计的方法。In addition, FIG. 6 shows the case where the RTT positioning method is used. In the RTT positioning method, it is a method of estimating the position of the mobile terminal at the intersection of the circle calculated from the RTT and the center line of the sector.

另外，在图2的步骤S209中，在选择了扇区定位时，也可以根据可观测的GPS卫星数、可测定RTT的基站数或者小区种类，从上述的扇区ID定位方式、小区ID定位方式、RTT定位方式中，详细选择使用哪一种定位方式。作为小区种类，例如可以举出是扇区小区或者整个小区。In addition, in step S209 of FIG. 2, when sector positioning is selected, the above-mentioned sector ID positioning method and cell ID positioning method can also be used according to the number of observable GPS satellites, the number of base stations that can measure RTT, or the type of cell. Mode and RTT positioning method, select which positioning method to use in detail. As the cell type, for example, a sector cell or a whole cell can be mentioned.

(变更例)(change example)

接着，使用图7对本实施方式的通信系统的变更例进行说明。如图7所示，在变更例的通信系统中，移动终端400收集定位方式的选择所需的信息。即，移动终端400根据可观测的GPS卫星数、可观测的基站数以及RTT的测定结果选择最佳定位方式，进行移动终端400的位置计算。Next, a modified example of the communication system of this embodiment will be described using FIG. 7 . As shown in FIG. 7 , in the communication system according to the modified example,mobile terminal 400 collects information necessary for selecting a positioning method. That is, themobile terminal 400 selects an optimal positioning method based on the number of observable GPS satellites, the number of observable base stations, and the RTT measurement results, and calculates the position of themobile terminal 400 .

变更例的通信系统具有蜂窝基站200、移动终端400和信息服务器500。A communication system according to a modified example includes acellular base station 200 , amobile terminal 400 , and aninformation server 500 .

蜂窝基站200与移动终端400进行通信。另外，蜂窝基站200测定蜂窝基站200～移动终端400之间的往返时间(RTT)。蜂窝基站200在接收到RTT测定的请求信号时，向移动终端400发送测定开始的请求信号。蜂窝基站200通过测定发送定时和接收定时来进行RTT测定。Thecellular base station 200 communicates with themobile terminal 400 . In addition, thecellular base station 200 measures the round-trip time (RTT) between thecellular base station 200 and themobile terminal 400 . Upon receiving the RTT measurement request signal, thecellular base station 200 transmits a measurement start request signal to themobile terminal 400 . Thecellular base station 200 performs RTT measurement by measuring transmission timing and reception timing.

另外，蜂窝基站200通过无线通信线路向移动终端400发送RTT的测定结果。In addition, thecellular base station 200 transmits the RTT measurement result to themobile terminal 400 via a wireless communication line.

移动终端400接收来自GPS卫星的信号，并与蜂窝基站200进行通信，进行位置计算。Themobile terminal 400 receives signals from GPS satellites, communicates with thecellular base station 200, and performs position calculation.

GPS接收部401包括接收来自卫星的信号的GPS天线、RF部、相关部和信号处理部。GPS接收部401采用在GPS天线接收到的信号中包含的GPS卫星信号序列的信息，确定接收卫星的卫星ID，并计算可接收的每个卫星的接收定时以及接收时刻。之后，GPS接收部101向位置检测部404发送包含可接收信号的GPS卫星数、该GPS卫星的卫星ID、接收定时以及接收时刻的GPS卫星信息。TheGPS receiving unit 401 includes a GPS antenna for receiving signals from satellites, an RF unit, a correlation unit, and a signal processing unit. TheGPS receiver 401 specifies the satellite ID of the receiving satellite using information on the GPS satellite signal sequence included in the signal received by the GPS antenna, and calculates the receiving timing and receiving time for each receivable satellite. Thereafter, theGPS receiving unit 101 transmits to theposition detecting unit 404 GPS satellite information including the number of GPS satellites receivable, the satellite ID of the GPS satellite, the receiving timing, and the receiving time.

蜂窝通信部402通过接收蜂窝基站200所发送的导频信号，来决定进行通信的蜂窝基站和其扇区。另外，蜂窝通信部402向定位信息解析部403发送包含基站ID以及该基站ID的所在扇区的基站信息。Thecellular communication unit 402 determines the cellular base station and its sector for communication by receiving the pilot signal transmitted from thecellular base station 200 . In addition, thecellular communication unit 402 transmits the base station information including the base station ID and the sector where the base station ID is located to the positioninginformation analysis unit 403 .

另外，蜂窝通信部402从蜂窝基站200接收RTT测定结果。蜂窝通信部402向定位信息解析部403发送从蜂窝基站200接收到的RTT测定结果。In addition, thecellular communication unit 402 receives the RTT measurement result from thecellular base station 200 . Thecellular communication unit 402 transmits the RTT measurement result received from thecellular base station 200 to the positioninginformation analysis unit 403 .

定位信息解析部403根据GPS卫星信息、基站信息和RTT测定结果选择最佳定位方式。作为定位方式，如上所述采用GPS定位、混合定位、扇区定位。The positioninginformation analysis unit 403 selects the optimal positioning method based on GPS satellite information, base station information, and RTT measurement results. As the positioning method, GPS positioning, hybrid positioning, and sector positioning are used as described above.

定位信息解析部302对利用这三种定位方式的位置定位误差进行估计。为了进行该估计，采用可用于位置计算的GPS卫星数以及基站数、信号的接收定时与卫星和基站的配置、所在扇区信息、以及RTT测定结果。关于定位方式选择方法，与图2中所说明的一样。The positioninginformation analysis unit 302 estimates position positioning errors using these three positioning methods. For this estimation, the number of GPS satellites and the number of base stations available for position calculation, signal reception timing, arrangement of satellites and base stations, location sector information, and RTT measurement results are used. The positioning method selection method is the same as that described in FIG. 2 .

位置检测部404使用定位信息解析部403中所选择的定位方式进行移动终端400的位置计算。Theposition detecting unit 404 calculates the position of themobile terminal 400 using the positioning method selected by the positioninginformation analyzing unit 403 .

变更例的定位方式选择方法由于与图2所示的流程图一样，因此在这里省略其说明。The positioning method selection method of the modified example is the same as the flow chart shown in FIG. 2 , so its description is omitted here.

(作用以及效果)(function and effect)

根据基于本实施方式的计算服务器300、移动终端100的定位方式的选择方法，可以根据蜂窝基站200和移动终端100之间的距离，选择使用小区/扇区定位或混合定位中的某一种定位方式，并使用所选择的定位方式来计算移动终端100的位置。According to the selection method of thecalculation server 300 and the positioning mode of themobile terminal 100 based on this embodiment, one of the cell/sector positioning or hybrid positioning can be selected according to the distance between thecellular base station 200 and themobile terminal 100 method, and use the selected positioning method to calculate the location of themobile terminal 100.

因此，能够在单独用GPS无法实施定位的状况下从可利用的定位方式中选择误差小的定位方式。Therefore, it is possible to select a positioning method with a small error from available positioning methods in a situation where positioning cannot be performed by GPS alone.

另外，也可以直接使用RTT来代替蜂窝基站200和移动终端100之间的距离。In addition, RTT may be directly used instead of the distance between thecellular base station 200 and themobile terminal 100 .

另外，在本实施方式中，根据小区/扇区定位的估计误差和混合定位的估计误差计算出规定的阈值。并且，将该规定的阈值与蜂窝基站～移动终端间的距离进行比较，在该距离比规定阈值小的情况下，选择小区/扇区定位。In addition, in this embodiment, the predetermined threshold is calculated based on the estimation error of cell/sector positioning and the estimation error of hybrid positioning. Then, the predetermined threshold is compared with the distance between the cellular base station and the mobile terminal, and when the distance is smaller than the predetermined threshold, cell/sector positioning is selected.

以往认为小区/扇区定位的精度比混合定位差，但是在小区大小较小的城市等中，也有小区/扇区定位的精度良好的情况。在本实施方式中，在这种情况下也可以选择定位误差小的定位方式。In the past, it was considered that the accuracy of cell/sector positioning is worse than that of hybrid positioning, but in cities with small cell sizes, etc., the accuracy of cell/sector positioning may be good. In this embodiment, a positioning method with a small positioning error can also be selected in this case.

另外，在选择定位方式时，除了距离，还可以根据基站的小区种类选择定位方式。例如，通过根据扇区小区或整个小区来选择定位方式，能够选择更符合实际的最佳定位方式。In addition, when selecting a positioning method, in addition to the distance, the positioning method can also be selected according to the cell type of the base station. For example, by selecting a positioning method according to a sector cell or an entire cell, it is possible to select an optimal positioning method that is more realistic.

Claims

1. A server device for estimating the position of a mobile terminal that receives signals from GPS satellites and communicates with a base station,

the disclosed device is provided with:

a positioning information analysis unit that selects one of cell/sector positioning and hybrid positioning to use, based on a distance between the base station and the mobile terminal; and

a position detection unit that calculates a position of the mobile terminal using the positioning method selected by the positioning information analysis unit; wherein,

the cell/sector positioning mode is a mode of calculating the center of a cell in which the mobile terminal is positioned or the center of a sector in which the mobile terminal is positioned as the position of the mobile terminal;

the hybrid positioning system is a system for measuring the position of a mobile terminal using signals received from GPS satellites and signals received from a base station; wherein,

the positioning information analysis unit calculates a predetermined threshold value from the estimation error of the cell/sector positioning and the estimation error of the hybrid positioning, compares the predetermined threshold value with the distance, and selects the cell/sector positioning when the distance is smaller than the predetermined threshold value; and if the distance is larger than a predetermined threshold value, determining whether hybrid positioning is possible or not according to the number of observable satellites, the number of observable base stations, and the positioning error, and if hybrid positioning is possible, selecting hybrid positioning, and if hybrid positioning is not possible, selecting cell/sector positioning.

2. The server apparatus according to claim 1,

and determining the distance according to the round trip time between the base station and the mobile terminal.

3. A mobile terminal that receives signals from GPS satellites and communicates with a base station,

the disclosed device is provided with:

4. A positioning method selection method for selecting a positioning method used when estimating a position of a mobile terminal which receives signals from GPS satellites and communicates with a base station,

the method comprises the following steps:

selecting one of cell/sector positioning and hybrid positioning according to the distance between the base station and the mobile terminal; and

calculating the position of the mobile terminal using the positioning method selected by the positioning information analysis unit; wherein,

calculating a predetermined threshold value from the estimation error of the cell/sector positioning and the estimation error of the hybrid positioning, comparing the predetermined threshold value with the distance, and selecting the cell/sector positioning when the distance is smaller than the predetermined threshold value; and if the distance is larger than a predetermined threshold value, determining whether hybrid positioning is possible or not according to the number of observable satellites, the number of observable base stations, and the positioning error, and if hybrid positioning is possible, selecting hybrid positioning, and if hybrid positioning is not possible, selecting cell/sector positioning.