Method for measuring distance and position using spread spectrum signal, and an equipment using the method

• US 20080068254A1
• Filed: 10/30/2007
• Published: 03/20/2008
• Est. Priority Date: 06/27/2000
• Status: Active Grant

• Current Assignee: Katsuhiko Tsunehara, Mikio Kuwahara, Nobukazu Doi, Tomoaki Ishifuji
• Original Assignee: Katsuhiko Tsunehara, Mikio Kuwahara, Nobukazu Doi, Tomoaki Ishifuji
• Inventors: Kuwahara, Mikio, Doi, Nobukazu, Tsunehara, Katsuhiko, Ishifuji, Tomoaki
• Granted Patent: US 7,663,532 B2
• Time in Patent Office: Days
• US Class Current: 342/125
• CPC Class Codes: G01S 1/026 of associated receivers
• CPC Class Codes: G01S 1/045 Receivers
• CPC Class Codes: G01S 5/0218 Multipath in signal reception
• CPC Class Codes: G01S 5/10 Position of receiver fixed by co-ordinating a plurality of position lines defined by path-difference measurements , e.g. omega or decca systemsG01S5/12 takes precedence ; beacons and receivers cooperating therewith G01S1/306, G01S1/308
• CPC Class Codes: H04B 1/70755 Setting of lock conditions, e.g. threshold
• CPC Class Codes: H04B 2201/70715 with application-specific features

Abstract

By using the delay profile created by delay profile creating section 102 and the first threshold value 330 received from the first threshold value calculation 105, the first threshold value timing detection section 103 selects only the earliest receive timing exceeding the first threshold value, from all the timing that the correlation value in the delay profile becomes a maximum. By using the receive timing and the second threshold value 331 received from the second threshold value calculation section 107, reference timing calculation section 106 selects the reference timing required for calculating the receive timing for the incoming wave of the minimum propagation delay time. The timing delayed by previously set timing behind said reference timing is sent from receive timing calculation section 108 as the receive timing 113 of the incoming wave of the minimum propagation delay time.

Claims

1. A method for measuring distance comprising:

a first step to create a delay profile from the signal wave received from a signal transmitting station;

a second step to detect the startup timing of the delay profile as reference timing; and

a third step to detect the timing delayed by a predetermined value behind the reference timing as the receive timing for the signal wave;

wherein the distance between the signal transmitting station and signal receiving station is measured from the difference between the transmitting timing of said signal transmitting station and the receive timing.