Position-Verified Access Apparatus, Method, and Program Product

• US 20050270232A1
• Filed: 06/02/2005
• Published: 12/08/2005
• Est. Priority Date: 06/02/2004
• Status: Active Grant

• Current Assignee: Lenovo PC International Limited (Lenovo Group Ltd.)
• Original Assignee: Lenovo Singapore Pte Limited (Lenovo Group Ltd.)
• Inventors: Masuda, Kazuo
• Granted Patent: US 7,609,201 B2
• Time in Patent Office: Days
• US Class Current: 342/357.250
• CPC Class Codes: G01S 19/03 Cooperating elements; Interaction or communication between different cooperating elements or between cooperating elements and receivers
• CPC Class Codes: G01S 19/14 specially adapted for specific applications
• CPC Class Codes: G01S 19/22 Multipath-related issues
• CPC Class Codes: G01S 19/23 Testing, monitoring, correcting or calibrating of receiver elements
• CPC Class Codes: G01S 19/42 Determining position

Abstract

An acquisition apparatus for acquiring the positional information indicating the position of a position detecting device which, in one embodiment, detects position based on a GPS (Global Positioning System). The position detecting device measures the device distance to each of a plurality of satellites and calculates the device position based on the device distance and the position of each of the plurality of satellites. The acquisition apparatus comprises a receiving part for receiving the device distance and the device position from the position detecting device, and a verification position calculating part for calculating the verification position that is the position to be calculated by the position detecting device, based on the received device distance and the position of each of the plurality of satellites at the time of measuring the device distance. The apparatus further includes a validity judgment part for judging that the device position detected by the position detecting device is valid, on condition that the device position is coincident with the verification position.

Claims

1. Apparatus comprising:

a receiver which receives a device distance and a device position from a position detecting device which measures the device distance from the position detecting device to each of a plurality of satellites and calculates the device position that is the position of the position detecting device based on the device distance and the position of each of the plurality of satellites;

a verification position calculator, coupled to said receiver, which calculates a verification position that is the position to be calculated by the position detecting device, based on the received device distance and the position of each of the plurality of satellites at the time of measuring the device distance; and

a validity circuit, coupled to said verification position calculator, which judges that the device position detected by the position detecting device is valid, on condition that the device position is coincident with the verification position.

2. Apparatus according to claim 1,

wherein the apparatus wirelessly communicates with the position detecting device over at least one wireless communication base station;

wherein said verification position calculator calculates as an other verification position the position to be calculated by the position detecting device, based on the position of the wireless communication base station over which communication with the position detecting device wirelessly occurs; and

wherein said validity circuit judges that the device position detected by the position detecting device is valid, further provided that the distance between the other verification position and the device position is within a predetermined reference distance.

3. Apparatus according to claim 1, wherein said validity circuit judges that the device position is valid, further provided that a time which has elapsed since the position detecting device measures the device distance until said receiver receives the device distance and the device position is less than a predetermined reference time.

4. Apparatus according to claim 1,

wherein the position detecting device measures the device distances between the position detecting device and each of at least five satellites, based on a time elapsed since each of the at least five satellites transmit a signal and until the position detecting device receives the signal;

and

wherein said verification position calculator calculates the verification position based on an equation, for each of the at least five satellites, whose unknowns are a clock error of the position detecting device and each element of the vector showing the coordinates of the device position, the equation showing that the distance to the satellite measured by the position detecting device, plus the clock error multiplied by the signal velocity is equal to the distance calculated based on the position of each of the at least five satellites and the device position.

5. Apparatus according to claim 1, further comprising:

a distance calculator, coupled to said validity circuit, which calculates the distance between the position of each of the plurality of satellites at the time of measuring the device distance by the position detecting device and the device position received by said receiver;

wherein the validity circuit judges that the device position is valid, further provided that the device distance received by said receiver differs from the distance calculated by said distance calculator by a predetermined difference value or more.

6. Apparatus according to claim 1,

wherein said receiver further receives from the position detecting device a device type identification information identifying the device type of the position detecting device;

and

wherein said verification position calculator calculates the verification position by a predetermined calculating method corresponding to the device type identification information.

7. Apparatus comprising:

a receiver which receives a device distance and a device position from a communication device which measures the device distance from the communication device to each of a plurality of satellites and calculates the device position that is the position of the communication device based on the device distance and the position of each of the plurality of satellites;

a verification position calculator, coupled to said receiver, which calculates a verification position that is the position to be calculated by the communication device, based on the received device distance and the position of each of the plurality of satellites at the time of measuring the device distance;

a validity circuit, coupled to said verification position calculator, which judges that the device position detected by the communication device is valid, on condition that the device position is coincident with the verification position; and

an access circuit, coupled to said validity circuit, which permits the communication device to gain access to a network on condition that it is judged that the device position of the communication device is valid and the device position is within a predetermined access permission area.

8. A method comprising:

receiving a device distance and a device position from a position detecting device which measures the device distance from the position detecting device to each of a plurality of satellites and calculates the device position that is the position of the position detecting device based on the device distance and the position of each of the plurality of satellites;

calculating a verification position that is the position to be calculated by the position detecting device, based on the received device distance and the position of each of the plurality of satellites at the time of measuring the device distance; and

judging that the device position detected by the position detecting device is valid, on condition that the device position is coincident with the verification position.

9. A method comprising:

receiving a device distance and a device position from a communication device which measures the device distance from the communication device to each of a plurality of satellites and calculates the device position that is the position of the communication device based on the device distance and the position of each of the plurality of satellites;

calculating a verification position that is the position to be calculated by the communication device, based on the received device distance and the position of each of the plurality of satellites at the time of measuring the device distance;

judging that the device position detected by the communication device is valid, on condition that the device position is coincident with the verification position; and

permitting the communication device to gain access to a network on condition that it is judged that the device position of the communication device is valid and the device position is within a predetermined access permission area.

10. A product comprising:

a computer usable medium having computer readable program code stored therein, the computer readable program code in said product being effective to;

receive a device distance and a device position from a position detecting device which measures the device distance from the position detecting device to each of a plurality of satellites and calculates the device position that is the position of the position detecting device based on the device distance and the position of each of the plurality of satellites;

calculate a verification position that is the position to be calculated by the position detecting device, based on the received device distance and the position of each of the plurality of satellites at the time of measuring the device distance; and

judge that the device position detected by the position detecting device is valid, on condition that the device position is coincident with the verification position.

11. A product comprising:

a computer usable medium having computer readable program code stored therein, the computer readable program code in said product being effective to;

receive a device distance and a device position from a communication device which measures the device distance from the communication device to each of a plurality of satellites and calculates the device position that is the position of the communication device based on the device distance and the position of each of the plurality of satellites;

calculate a verification position that is the position to be calculated by the communication device, based on the received device distance and the position of each of the plurality of satellites at the time of measuring the device distance;

judge that the device position detected by the communication device is valid, on condition that the device position is coincident with the verification position; and

permit the communication device to gain access to a network on condition that it is judged that the device position of the communication device is valid and the device position is within a predetermined access permission area.