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US5036330A
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Ranging system using correlation between two spread spectrum wave signals
Assignee: National Institute of Information and Communications Technology
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Filing: 1990-03-26
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Granted: 1991-07-30
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Expires: 2010-03-26
Abstract
Abstract A ranging system using the correlation between two spread spectrum wave signals includes an antenna for receiving from a single radio source two spread spectrum modulated signals simultaneously transmitted in the same code on carrier waves of different frequency, a multiplier for multiplying the received signals by each other to generate two continuous signals of frequencies respectively equal to the difference and the sum of the carrier waves of the spread spectrum signals, and a data processing computer for measuring the phases of the two continuous signals with reference to a reference clock at the receiving station so as to remove the ambiguity at the time of range measurement.
Inventors
- 👤 Michito Imae
- 👤 Chihiro Miki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 14:28
CPC Classifications
G; G01; G01S; G01S19/00; G01S19/01; G01S19/13; G01S19/32; G01S19/24; G01S19/30
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
103 words
A ranging system using the correlation between two spread spectrum wave signals comprising means for receiving from a single radio source two spread spectrum modulated signals simultaneously transmitted in the same code on carrier waves of different frequency, means for multiplying the received signals by each other to generate two continuous signals of frequencies respectively equal to the difference and the sum of the carrier waves of the spread spectrum signals, and means for measuring the phases of the two continuous signals with reference to a reference clock at the receiving station, whereby the ambiguity at the time of range measurement is removed.
Claim 2
Dependent Claim
103 words
A ranging system using the correlation between two spread spectrum wave signals comprising means for receiving from a single radio source two spread spectrum modulated signals simultaneously transmitted in the same code on carrier waves of different frequency, means for multiplying the received signals by each other to generate two continuous signals of frequencies respectively equal to the difference and the sum of the carrier waves of the spread spectrum signals, and means for measuring the phases of the two continuous signals with reference to a reference clock at the receiving station, whereby the ambiguity at the time of range measurement is removed.
References Cited (Backward Citations)
US4809005A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-07-29 | 1995-01-28 | 1995-07-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-07-29 | 1999-01-28 | 1999-07-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-07-29 | 2003-01-28 | 2003-07-30 | $7700.00 | Window Closed / Lapsed |