Method for performing positioning and an electronic device

• US 6,714,159 B1
• Filed: 09/16/2002
• Issued: 03/30/2004
• Est. Priority Date: 09/17/2001
• Status: Expired due to Fees

• Current Assignee: Nokia Corporation
• Original Assignee: Nokia Corporation
• Inventors: Syrjärinne, Jari, Alanen, Kimmo
• Primary Examiner(s): Tarcza, Thomas H.
• Assistant Examiner(s): MULL, FRED H
• Application Number:
  US10/246,129
• Time in Patent Office: 561 Days
• Field of Search: 342/357.06, 342/357.12, 342/357.13, 342/357.15
• US Class Current: 342/357.25
• CPC Class Codes: G01S 19/24 Acquisition or tracking or demodulation of signals transmitted by the system synchronisation aspects of direct sequence spread spectrum modulation H04B1/7073
• CPC Class Codes: G01S 19/42 Determining position

Abstract

The invention relates to a method for performing positioning, in which a spread spectrum signal modulated with a repetition code and transmitted by satellites, is received. The method comprises the steps of acquiring the received, spread spectrum modulated signal, measuring the code phase of the received, spread spectrum modulated signal, and receiving the Ephemeris parameters of satellites which are used in the positioning. Furthermore, in the method, said code phase measurement results are stored, which have been measured at least partly before receiving the Ephemeris parameters, wherein the stored measurement results are used in the positioning after the Ephemeris parameters have been received.

Claims

1. A method for performing positioning, comprising the steps of receiving a spread spectrum signal modulated with a repetition code and transmitted by satellites;

performing acquisition of the received spread spectrum modulated signal;

measuring the code phase of the received spread spectrum modulated signal; and

receiving satellite position information to be used in the positioning, wherein in the method, said code phase measurement results, which have been measured at least partly before receiving the position information, are stored, wherein the stored measurement results are used for positioning after the position information has been received.

2. The method according to claim 1, wherein said measurement results are filtered.

3. The method according to claim 2, wherein a Kalman filter is used in the filtering.

4. The method according to claim 1, wherein position information is received from the signal transmitted by the satellites.

5. The method according to claim 1, wherein for performing the positioning, the spread spectrum modulated signal transmitted by at least four satellites is received, the code phase of each received signal is measured, the measurements results of each received signal are stored, the position information of said at least four satellites is received, wherein the positioning is performed after the position information of said at least four satellites has been received, and the measurement results stored from the received signals are used in the positioning.

6. An electronic device comprising means for performing positioning, comprising means for receiving a spread spectrum signal modulated with a repetition code and transmitted by satellites;

means for acquiring the received spread spectrum modulated signal;

means for measuring the code phase of the received spread spectrum modulated signal; and

means for receiving the position information of satellites to be used in the positioning, the electronic device also comprising at least means for storing said code phase measurement results which have been measured at least partly before receiving the position information, and means for using said stored measurement results in the positioning after position information has been received.

7. The electronic device according to claim 6 also comprising means for filtering measurement results.

8. The electronic device according to claim 7, said means for filtering measurement results comprising a Kalman filter.

9. An electronic device according to claim, 6, wherein the means for receiving the position information of the satellites to be used in the positioning comprise means for receiving the position information from the signal transmitted by the satellites.

10. The electronic device according to claim 6, comprising means for receiving the signals transmitted by at least four satellites substantially simultaneously;

means for measuring the code phase of each received spread spectrum modulated signal;

means for storing the measurement results of the code phase of the signal of said at least four satellites, which have been measured at least partly before receiving the position information;

means for receiving the position information of at least four satellites used in the positioning; and

means for using said stored measurement results in the positioning after position information has been received.

11. A method for performing positioning, comprising the steps of receiving a spread spectrum signal modulated with a repetition code and transmitted by satellites;

performing acquisition of the received spread spectrum modulated signal;

measuring the code phase of the received spread spectrum modulated signal; and

receiving satellite position information to be used in the positioning, wherein in the method, said code phase measurement results, which have been measured at least partly before receiving the position information from the signal transmitted by the satellites, are stored, wherein the stored measurement results are used for positioning after the position information has been received, in which method for performing the positioning, the spread spectrum modulated signal transmitted by at least four satellites is received, the code phase of each received signal is measured, the measurements results of each received signal are stored, the position information of said at least four satellites is received, wherein the positioning is performed after the position information of said at least four satellites has been received, and the measurement results stored from the received signals are used in the positioning.

12. An electronic device comprising means for performing positioning, comprising means for receiving a spread spectrum signal modulated with a repetition code and transmitted by satellites;

means for acquiring the received spread spectrum modulated signal;

means for measuring the code phase of the received spread spectrum modulated signal;

means for receiving the position information of satellites to be used in the positioning;

means for storing said code phase measurement results which have been measured at least partly before receiving the position information, means for using said stored measurement results in the positioning after position information has been received;

means for receiving the signals transmitted by at least four satellites substantially simultaneously;

means for measuring the code phase of each received spread spectrum modulated signal;

means for storing the measurement results of the code phase of the signal of said at least four satellites, which have been measured at least partly before receiving the position information;

means for receiving from the signals transmitted by the satellites the position information of at least four satellites used in the positioning; and

means for using said stored measurement results in the positioning after position information has been received.