WO2014147606A1

WO2014147606A1 - System and method for implementation of retrieval of gps data

Info

Publication number: WO2014147606A1
Application number: PCT/IL2014/000018
Authority: WO
Inventors: Roy Glasberg; Ishay Barlev
Original assignee: U-Tx Ltd.
Priority date: 2013-03-21
Filing date: 2014-03-20
Publication date: 2014-09-25

Abstract

A method for third party determining the location of a wireless device using GPS data, comprising sending a request message from a third party, asking for GPS assistance data, to a predetermined wireless device, the wireless device having a GPS receiver; receiving a response message from the wireless device, the response comprising GPS assistance data; calculating and determining the location of the wireless device.

Description

SYSTEM AND METHOD FOR IMPLEMENTATION OF RETRIEVAL OF GPS DATA

FIELD OF THE INVENTION

The present invention generally relates to mobile telephone technology, and more particularly to a system and method for implementation of assistance data for GPS.

BACKGROUND OF THE INVENTION

Mobile phones having GPS receiving capabilities are widespread, and are utilized in a plurality of cellular phone applications which take note of a user's location. The GPS determining capabilities must typically be initially activated or defined as "allowed" by a user.

It would be advantageous in certain circumstances to allow a third party to locate a user's cellular phone, such as when law enforcement personnel wish to locate lost individuals.

It is an object of the present invention to provide a method of ascertaining the location of a wireless device using GPS location, even when an individual has turned off the GPS locator functions on his wireless device.

These and other objects will be better described hereinbelow.

SUMMARY OF THE INVENTION

Glossary

Assistance Data (AD) is a set of data provided to the Mobile Station (MS) by the network and used by an Assisted-Global Positioning System (A-GPS) capable MS to improve measurement performance: i.e., to accurately and precisely locate and utilize the satellites faster in order to decrease the calculation time of its GPS location. The definition applies only to MS-based methods.

The National Marine Electronics Association (NMEA) standard for communicating with GPS receivers is a simple, yet comprehensive American Standards Code Information Interchange (ASCII), serial communications protocol which defines both the communication interface and the data format. It is used for communication between electronic devices such as GPS receivers and many other types of instruments. ASCII is a code in which alphanumeric characters are represented as eight-digit binary numbers.

A-GPS positioning methods

There are two basic methods of assisted GPS employed in MS:

MS-assisted

Is defined as an implementation where assistance data is provided to the MS, by the network, such that the MS can acquire GPS satellite signals and determine their corresponding pseudo-range measurements. These time- stamped satellite pseudo-ranges are returned to the network, where the location estimate is then calculated.

- MS-based

o Is defined as an implementation where assistance data is provided to the MS, by the network, such that the MS can calculate its own location estimate. Both methods require a GPS receiver to be integrated into MS.

Accordingly, the MS-based method is presently preferred for the present invention. This method is depicted in Table I.

Table I MS-based Assisted GPS positioning method:

The Differential Global Positioning System (DGPS) uses a network of fixed, ground- based reference stations to broadcast the difference between positions indicated. The GPS almanac is a set of data that every GPS satellite transmits, including information about the state of the entire GPS satellite population of the network, and coarse data on every satellite's orbit. When a GPS receiver has current almanac data in memory, it can acquire satellite signals and determine initial position more quickly.

MS Prerequisites for Global System for Mobile Communications (GSM)

In order to retrieve a GPS location estimate from an MS, it should:

Has an integrated GPS receiver;

Supports LCS (Location Services).

Supports MS based GPS capability.

In one embodiment, the present invention is applied at one or more checkpoints, in a specific area, for example, at an airport. There are mobile phone towers in the area. There is a surreptitious tower, provided separately from the towers of the mobile phone network by the system of the present invention (named Private Network or NW). The target phone is in the purview of the PN, and the phone is sending measurements and information to the PN tower.

The present invention uses assisted GPS (AGPS). If a smart phone with such GPS capabilities "sees" the sky, it can see the GPS satellites, get the signals from them and basically find its own position, similar to the operation of a GPS device in a car. Also the real network can do the calculation itself. The mobile phone still calculates the GPS position. The operator of the present invention system gives this information to the phone. The phone finishes the calculation and gets the position in seconds. It is helpful if the protocol is known and to know which pieces of information the cellular network operator must pass to the phone. This technique is accurate for meters up to tens of meters in the worst case. If silent call is used, the information is made available in a continuous way.

The present invention also incorporates a public safety technique regarding any GPS- capable mobile device. The operator can send a command to locate the position of any mobile with A-GPS, even if the GPS capability of the device was turned off by the user of the mobile device.

The present invention can be used for finding lost people, such as lost teenagers, locating someone injured in a car crash, etc. If the person calls the 911 operator the operator can signal the cell phone and get the GPS location. This works even if the user of the cell phone turns off his GPS capability. The user's menu indicates that the GPS feature is off. Phones belonging to people who work at the checkpoint are "blacklisted" so as not to be affected by this operation.

Accordingly, it is a principal object of the present invention to ascertain the location of a wireless device using GPS location.

It is another principal object of the present invention to connect a wireless device to a network such as a GSM/UMTS communication network and use messages including standard defined messages to cause the wireless device to send data without alerting the users of the wireless device.

It is one other principal object of the present invention to enable retrieval of GPS/A- GPS coordinate measurements of the wireless device.

It is yet another principal object of the present invention to provide a gathering system that may be an unrelated standalone device and/or not connected to the serving network of the wireless device.

The GPS location data retrieval is accomplished by sending a special request message (which may contain some assistance data) to the mobile device. Assistance data may include precise satellite orbital elements (such as: almanac, approximate position and time, atmospheric interference and delays, ephemeris or its compressed equivalent).

The mobile device may use this assistance data to shorten the time needed to perform a position calculation. The mobile device sends the location data back to the network. These request/response messages are a part of standard mobile communication protocol that allows GPS location retrieval from mobile device for emergency and rescue purposes. Location data retrieval process is transparent and mostly undetectable or completely undetectable for the mobile device's user. This process can be performed by means of a standalone software and base transceiver system. It may be done simultaneously with other location activity such as ones using direction finding of RF signals.

There has thus been outlined, rather broadly, the more important features of the invention in order that the detailed description thereof that follows hereinafter may be better understood. Additional details and advantages of the invention will be set forth in the detailed description, and in part will be appreciated from the description, or may be learned by practice of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

In order to understand the invention and to see how it may be carried out in practice, a preferred embodiment will now be described, by way of a non-limiting example only, with reference to the accompanying drawings. In the drawings:

FIG. 1 shows the GPS Harvest Architecture, constructed according to exemplary embodiments of the present invention;

FIG. 2 is a GSM/UMTS Data Flow diagram showing the GPS Harvest request during presence verification, constructed according to exemplary embodiments of the present invention;

FIG. 3 is a data flow diagram illustrating the message flow for a GPS harvest during a GSM/UMTS location update, constructed according to exemplary embodiments of the present invention; and

FIG. 4 is a data flow diagram illustrating assistance data retrieval, constructed according to exemplary embodiments of the present invention.

All the above and other characteristics and advantages of the invention will be further understood through the following illustrative and non-limitative description of preferred embodiments thereof.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

The principles and operation of a method and an apparatus according to the present invention may be better understood with reference to the drawings and the accompanying description, it being understood that these drawings are given for illustrative purposes only and are not meant to be limiting. FIG. 1 shows the GPS Harvest Architecture, constructed according to exemplary embodiments of the present invention, connected to a personal computer and mobile phone. General GPS harvest architecture: Structure, Components and Interfaces.

The Common GPS Parser 130 is a component which communicates with a dedicated, AD capable GPS receiver 1 10. Each specific GPS receiver device 110 has a software implementation module based on this Common Parser 130 and has its own interface with the receiver 1 10. Also, each parser will have its own data processing implementation that converts the received AD from the receiver in a format defined by the 3GPP standard which is accepted by the MS. Such a flexible modular design allows using different GPS receiver devices with their own parser implementations that can be used within the GPS harvest system.

GPS Parser is responsible for:

Communication with GPS receiver:

o Retrieving AD

o Retrieving current GPS receiver location

o Retrieving GPS status

Communication with AGPS Location Manager:

o Sending converted AD on request

o Sending GPS status on request

o Sending current GPS receiver location on request

Converting assistance data (AD) to 3^rd generation partnership project (3GPP) format The GPS Parser 120 is based on the Common GPS parser 130. The communication between parser 120 and receiver 1 10 is done using the NMEA protocol via a serial COM interface. GPS receiver 1 10 supports the latest release of NMEA with additional proprietary NMEA sentences which allow retrieving the information used for assistance data.

The AGPS Location Manager (LM) 140 is responsible for:

Communication with common GPS Parser 130

o Retrieving AD

o Retrieving current GPS receiver location

o Retrieving current GPS status

Communication with the Client User Interface (Ul) 142

o Sending GPS harvest status

Communication with the 3G/2G Manager 143

o Sending GPS harvest status

o Sending AD

Enabling/disabling of GPS harvest functionality depending on license availability and GPS receiver status. AGPS LM 140 should constantly request AD from GPS Parser 130 based on a timer timeout. The optimal timeout value will be calculated experimentally. At the moment new AD is retrieved, it is sent to the 3G/2G Manager 143, which forwards the data to the 3G/2G BSC 150.

The caching of AD is done inside the 3G/2G BSC 150 as soon as it is sent by AGPS LM 140.

Data Structures

GPS Assistance Data is a detailed list of assistance data required by MS is presented below in Tables II through VII. The components which constitute the assistance data are optional, as an MS will only use a subset of this information. For example, it may be enough for the MS to use only approximate position, ephemeris, and approximate time.

Location Information: The MS can return the position to the network via a Location Information message: 3GPP TS 04.31 - A.3.2.4. The message contains the device's position data along with optional uncertainty and altitude.

Workflow

FIG. 2 is a Data Flow diagram showing the GPS Harvest request during presence verification (215), constructed according to exemplary embodiments of the present invention.

1. Client Ul sends 210 a presence verification request 221 to the 3G/2G BSC 230.

2. 3G/2G BSC 230 sends a CheckAlive page to the target 231.

3. Target answers 251.

4. Network Measure Report (NMR) request is sent 232 (a list of neighbors).

5. Position Request is sent 233 using RRLP protocol if:

a. GPS Harvest feature is enabled;

b. AD is present; and

c. Phone supports AGPS capabilities.

If at least one of these is not present, a fallback to NMR workflow is done 252.

6. The target is kept alive until one of the following will happen:

a. RRLP protocol error is received 253;

b. Measure Position Response is received 234; or

c. Timeout (x seconds) (An exemplary, non-binding default value should be

decided)

7. If RRLP error is received, 3G/2G BSC sends NMR results to 3G/2G Manager, which in its turn forwards them to AGPS Location Manager 222.

8. In case Measure Position Response is received from the target 254, NMR result sending is blocked and MS GPS Location is sent 235 to 3G/2G Manager instead. 9. 3G/2G Manager sends MS location to Client Ul 223.

10. The channel is released

FIG. 3 is a data flow diagram illustrating the message flow for a GPS harvest during a location update, constructed according to exemplary embodiments of the present invention.

1. MS sends a Location Update to the 3G/2G BSC 351.

2. A network measurement record (NMR) request is sent to a list of neighbors 331.

3. A Position Request is sent 332 using Radio Resource Location services (LCS) Protocol (RRLP) if:

a. The GPS Harvest feature is enabled.

b. AD is present.

c. The phone supports AGPS capabilities.

If at least one of these is not present, a fallback to NMR workflow is done (352).

4. The target is asked for identity until one of the following happens:

a. RRLP protocol error is received (353)

b. Measure Position Response is received

c. Timeout (x seconds) (An exemplary, non-binding default value should be decided)

5. Accept/Reject message is sent to the target.

6. Accept/Reject message is sent to Client Ul.

7. Channel is released

8. If RRLP error was received, 3G/2G BSC sends NMR results (333) to 3G/2G Manager, which in its turn forwards them (321) to AGPS Location Manager.

9. In case Measure Position Response was received (354) from the target, NMR result sending is blocked and MS GPS Location is sent (334) to 3G/2G Manager instead.

10. 3G/2G Manager sends MS location (322) to Client Ul.

FIG. 4 is a data flow diagram illustrating assistance data retrieval, constructed according to exemplary embodiments of the present invention

1. AGPS LM on a timeout requests AD from GPS Parser 431.

2. GPS Parser requests AD from GPS receiver 421.

3. AGPS LM receives the AD 432 and sends it 433 to 3G/2G Manager.

4. AD is sent 441 to the 3G/2G BSC and is cached there. GPS Assistance Data

Table II: Required Assistance Data

Table III: Reference Time

Parameter # Bits Scale Range Units Incl.

Factor

GSM Time 1 Boolean M Present

GPS Week 10 1 0 - 1023 weeks M

GPS TOW 23 0.08 0-604799.92 sec M

Table IV: Navigation Model

Table V: Ionospheric Model

Table VI: Universal Time (UTC) Model

Table VII: Almanac

Claims

1. A method for third party determining the location of a wireless device using GPS data, comprising:

sending a request message from a third party, asking for GPS assistance data, to a predetermined wireless device, said wireless device having a GPS receiver;

receiving a response message from said wireless device, said response comprising GPS assistance data;

calculating and determining the location of said wireless device.

2. The method of claim 1 , further comprising:

providing a surreptitious tower in the vicinity of said wireless device,

acquiring said target device by the system;

obtaining measurements by the system, the measurements comprising the relative position of the target device to said surreptitious network tower;

identifying the relative position of the target device; and

running an algorithm by the system to calculate the position of the target device relative to the towers by triangulation,

identifying the location of said target device.

3. The method of claim 1 , wherein the wireless device is a mobile phone.

4. The method of claim 1 , wherein the wireless device is selected from: a cellular phone, a PDA, a tablet, a laptop, a device having a Global Positioning System receiver, and a wireless tracker tag.