NOVAS HYBRID POSITIONING TECHNOLOGY USING TERRESTRIAL DIGITAL BROADCASTING SIGNAL (DBS) AND GLOBAL POSITIONING SYSTEM (GPS) SATELLITE SIGNAL

• US 20100171660A1
• Filed: 03/18/2010
• Published: 07/08/2010
• Est. Priority Date: 11/15/2005
• Status: Active Grant

• Current Assignee: Maishi Electronic (Shanghai) Limited
• Original Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Inventors: SHYR, You-Yuh Jack, JI, CUICHAI, CHENG, MINGQIANG
• Granted Patent: US 8,004,460 B2
• Time in Patent Office: Days
• US Class Current: 342/357.620
• CPC Class Codes: G01S 19/48 by combining or switching between position solutions derived from the satellite radio beacon positioning system and position solutions derived from a further system

Abstract

A positioning method using global positioning system (GPS) signal and digital broadcasting system (DBS) signal. The method includes detecting a presence status of the GPS signal through a signal detector in a receiver, detecting a presence status of the DBS signal through the signal detector, determining the signal strength of the GPS signal if the GPS signal is detected, determining the signal strength of the DBS signal if the DBS signal is detected, choosing one positioning mode among a plurality of positioning modes in a signal processing unit in the receiver based on signal presence status and the signal strength of a detected signal, and determining a location of the receiver based on the chosen positioning mode. The plurality of positioning modes includes standalone GPS mode, assisted GPS (AGPS) mode, assisted GPS positioning with DBS assist mode, DBS positioning with GPS assist mode, standalone DBS mode, and assist DBS mode.

Claims

1. A receiver for receiving wireless signals from transmitters to calculate location information, comprising:

a first tuner for receiving a global positioning system (GPS) signal, the GPS signal having a signal strength;

a second tuner for receiving a digital broadcasting system (DBS) signal, the DBS signal having a signal strength;

a signal detecting unit for detecting a signal-to-noise ratio for the GPS signal and a signal-to-noise ratio for the DBS signal, the signal detecting unit outputting a signal indicating an positioning mode based on the signal-to-noise ratios of the GPS signal and the DBS signal;

a hybrid signal processing unit in communication with the first tuner, the second tuner, and the signal detecting unit, the hybrid signal processing unit capable of operating in standalone GPS mode, standalone DBS mode, or assisted mode according to the positioning mode and determining a position of the transmitters and difference between the time the GPS signal and the DBS signal are received at the receiver; and

a measurement data processing unit coupled to the hybrid signal processing unit for determining the location information of the receiver based on the position of the transmitters and the difference between the time the GPS signal and the DBS signal are received at the receiver.

2. The receiver of claim 1, further comprising an assist data processing unit coupled to the hybrid signal processing unit for receiving assistance data from an assist station and providing the assistance data to the hybrid signal processing unit for further signal processing when an assist positioning mode is chosen.

3. The receiver of claim 1, wherein the hybrid signal processing unit further being capable of operating a first assist positioning mode for providing time synchronization information from the DBS signal to reduce synchronization time required in an assisted GPS positioning mode, wherein the hybrid signal processing unit uses GPS signal to determine a position based on the assistance data and DBS signal.

4. The receiver of claim 1, wherein the hybrid signal processing unit further being capable of operating in an assisted GPS positioning mode, wherein the hybrid signal processing unit uses the GPS signal to determine position based on the assistance data.

5. The receiver of claim 1, wherein the hybrid signal processing unit operating in the standalone GPS mode, the hybrid signal processing unit only processes GPS signals.

6. The receiver of claim 1, wherein the hybrid signal processing unit further being capable of operating in a second assist positioning mode for providing a GPS signal to assist DBS positioning when the transmitters transmitting the DBS signal are limited and the transmitters transmitting the GPS signal are limited, wherein the hybrid signal processing unit uses both DBS signal and GPS signals to determine a position.

7. The receiver of claim 1, wherein the hybrid signal processing unit operating in the standalone DBS mode, the DBS positioning mode being chosen when the presence of GPS signals is not detected by the signal detector, wherein the hybrid signal processing unit only processes the DBS signal.

8. The receiver of claim 1, wherein the hybrid signal processing unit further being capable of operating in an assist DBS positioning mode, wherein the hybrid signal processing unit uses the DBS signals to determine position based on the assistant DBS signal.

9. A positioning method for a receiver using global positioning system (GPS) signal and digital broadcasting system (DBS) signal, wherein GPS signal having a signal strength and DBS signal also having a signal strength, comprising:

detecting presence of the GPS signal through a signal detector;

detecting presence of the DBS signal through the signal detector;

determining the signal strength of the GPS signal if the GPS signal is detected;

determining the signal strength of the DBS signal if the DBS signal is detected;

determining a ratio between the signal strength of the GPS signal and the signal strength of the DBS signal;

choosing one positioning mode among a plurality of positioning modes based on the presence of detected signals and the ratio between the signal strength of the GPS signal and the signal strength of the DBS signal; and

determining a current position based on the chosen positioning mode,

wherein the plurality of positioning modes comprises

a first assist positioning mode for obtaining a time synchronization information from the DBS signal to reduce synchronization time required in an assisted GPS positioning mode, wherein the receiver uses the GPS signal to determine a position based on assistance data and the DBS signal,

an assisted GPS positioning mode, wherein the receiver uses the GPS signal to determine a position based on assistance data from an assist server, and

a standalone GPS positioning mode, wherein the receiver only receives the GPS signal.

10. The method of claim 9, wherein the plurality of positioning modes further comprising a second assist positioning mode for providing the GPS signal to assist a DBS positioning mode when the number of transmitters transmitting the DBS signal are limited and the number of transmitters transmitting the GPS signal are limited, wherein the receiver uses both DBS signal and GPS signals to determine position.

11. The method of claim 9, wherein the plurality of positioning modes further comprising a DBS positioning mode, the DBS positioning mode being chosen when the presence of the GPS signals is not detected by the signal detector, and wherein receiver only processes DBS signals.

12. The method of claim 9, wherein the plurality of positioning modes further comprising an assist DBS positioning mode, wherein the receiver uses the DBS signals to determine position based on the assistant DBS signal.

13. A receiver for receiving wireless signals from transmitters to calculate location information, comprising:

a first tuning means for receiving a global positioning system (GPS) signal, the GPS signal having a signal strength;

a second tuning means for receiving a digital broadcasting system (DBS) signal, the DBS signal having a signal strength;

means for detecting a signal-to-noise ratio for the GPS signal and a signal-to-noise ratio for the DBS signal, the means for detecting the signal-to-ratio outputting a signal indicating an positioning mode based on the signal-to-noise ratios of the GPS signal and the DBS signal;

means for processing hybrid signals in communication with the first tuning means, the second tuner, and the means for detecting the signal-to-ratio, the means for processing hybrid signals capable of operating in standalone GPS mode, standalone DBS mode, or assisted mode according to the positioning mode and determining a position of the transmitters and difference between the time the GPS signal and the DBS signal are received at the receiver; and

means for processing measurement data coupled to the means for processing hybrid signals, the means for processing measurement data being capable of determining the location information of the receiver based on the position of the transmitters and the difference between the time the GPS signal and the DBS signal are received at the receiver.

14. The receiver of claim 13, further comprising an assist data processing means coupled to the means for processing hybrid signals for receiving assistance data from an assist station and providing the assistance data to the hybrid signal processing unit for further signal processing when an assist positioning mode is chosen.

15. The receiver of claim 13, wherein the means for processing hybrid signals further being capable of operating a first assist positioning mode for providing time synchronization information from the DBS signal to reduce synchronization time required in an assisted GPS positioning mode, wherein the means for processing hybrid signals uses GPS signal to determine a position based on the assistance data and DBS signal.

16. The receiver of claim 13, wherein the means for processing hybrid signals further being capable of operating in an assisted GPS positioning mode, wherein the means for processing hybrid signals uses the GPS signal to determine position based on the assistance data.

17. The receiver of claim 13, wherein the means for processing hybrid signals operating in the standalone GPS mode, the means for processing hybrid signals only processes GPS signals.

18. The receiver of claim 13, wherein the means for processing hybrid signals further being capable of operating in a second assist positioning mode for providing a GPS signal to assist DBS positioning when the transmitters transmitting the DBS signal are limited and the transmitters transmitting the GPS signal are limited, wherein the means for processing hybrid signals uses both DBS signal and GPS signals to determine a position.

19. The receiver of claim 13, wherein the means for processing hybrid signals operating in the standalone DBS mode, the DBS positioning mode being chosen when the presence of GPS signals is not detected by the signal detector, wherein the means for processing hybrid signals only processes the DBS signal.

20. The receiver of claim 13, wherein the means for processing hybrid signals further being capable of operating in an assist DBS positioning mode, wherein the means for processing hybrid signals uses the DBS signals to determine position based on the assistant DBS signal.