GPS receiver

• US 7,649,494 B2
• Filed: 06/05/2006
• Issued: 01/19/2010
• Est. Priority Date: 06/09/2005
• Status: Active Grant

• Current Assignee: Seiko Epson Corporation (Seiko Group)
• Original Assignee: Seiko Epson Corporation (Seiko Group)
• Inventors: Matsumoto, Kazumi, Terashima, Maho
• Primary Examiner(s): Ghayour; Mohammad H
• Assistant Examiner(s): DSOUZA, JOSEPH FRANCIS A
• Application Number:
  US11/446,216
• Publication Number:
  US 20060280233A1
• Time in Patent Office: 1,324 Days
• Field of Search: 340/426.19, 340/539.13, 342/357.06, 342/357.12, 701/213, 701/215
• US Class Current: 342/357.63
• CPC Class Codes: G01S 19/30 code related G01S19/246 takes precedence
• CPC Class Codes: G01S 19/37 Hardware or software details of the signal processing chain

Abstract

A GPS receiver which performs correlation processing by using replicas of C/A codes generated in the GPS receiver after a GPS signal received from a GPS satellite is subjected to accumulating processing, wherein in the accumulating processing, a plurality of signals for integrating generated in the GPS receiver by predicting modulation of the GPS signal by a navigation message are integrated with the received GPS signal, and results of the integration are accumulatively added.

Claims

1. A GPS receiver comprising:

receiving means that receives GPS signals modulated by a navigation message;

bit pattern signal generating means that predicts modulation of the GPS signals by the navigation message, and generates bit pattern signals corresponding to each of a plurality of bit patterns that differ from each other while making phases different at predetermined intervals, the number of the bit pattern signals corresponding to each of the plurality of bit patterns being obtained by dividing a 1-bit length of the navigation message by the predetermined interval, the predetermined interval being equal to or more than one cycle of C/A codes and less than the 1-bit length of the navigation massage;

integrating means that integrates each of the bit pattern signals generated by the bit pattern signal generating means with the GPS signals received by the receiving means; and

accumulative adding means that accumulatively adds signals output from the integrating means,

the C/A codes being Clear and Acquisition codes or Coarse and Access codes.

2. A method of controlling a GPS receiver, comprising:

receiving GPS signals modulated by a navigation message;

predicting modulation of the GPS signals by the navigation message, and generating bit pattern signals corresponding to each of a plurality of bit patterns that differ from each other while making phases different at predetermined intervals, the number of the bit pattern signals corresponding to each of the plurality of bit patterns being obtained by dividing a 1-bit length of the navigation message by the predetermined interval, the predetermined interval being equal to or more than one cycle of C/A codes and less than the 1-bit length of the navigation message;

integrating each of the bit pattern signals generated by the bit pattern signal generating means with the GPS signals received by the receiving means; and

accumulatively adding signals output from the integrating means,

the C/A codes being Clear and Acquisition codes or Coarse and Access codes.