US3798641A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Process and system for the identification of a vehicle
Assignee: Societe de Fabrication dInstruments de Mesure SFIM SA
•
Filing: 1971-05-03
•
Granted: 1974-03-19
•
Expires: 1991-05-03
Abstract
Abstract A method and system for identifying a vehicle. An interrogation station transmits a frequency modulated continuous microwave to a vehicle having responder equipment which modulates the received microwave in accordance with an identifying binary code which is decoded at the interrogation station which receives the reflected modulated microwave. The modulation may be further frequency modulated at two different frequencies or may be modulated to give decoded pulses having different widths.
Inventors
- 👤 J Preti
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 04:06
CPC Classifications
B; B61; B61L; B61L25/00; B61L25/02; B61L25/04; B61L25/045; G; G01; G01S; G01S13/00; G01S13/74; G01S13/82
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
114 words
In a process for the identification of a vehicle from an interrogation station, in which the interrogation station transmits a continuous microwave to a zone through which the vehicle passes, the vehicle receives this microwave when it is passing through the zone and reflects the wave to the interrogation station in the form of a modulated reflected wave, this modulation comprising a coding characteristic of the vehicle, and the interrogation station receives the modulated reflected wave and detects the code which it contains, the improvement comprising said wave transmitted by the interrogation station being frequency modulated with a modulation frequency equal at least to one thousand times the modulation frequency of the reflected wave.
Claim 2
Dependent Claim
114 words
In a process for the identification of a vehicle from an interrogation station, in which the interrogation station transmits a continuous microwave to a zone through which the vehicle passes, the vehicle receives this microwave when it is passing through the zone and reflects the wave to the interrogation station in the form of a modulated reflected wave, this modulation comprising a coding characteristic of the vehicle, and the interrogation station receives the modulated reflected wave and detects the code which it contains, the improvement comprising said wave transmitted by the interrogation station being frequency modulated with a modulation frequency equal at least to one thousand times the modulation frequency of the reflected wave.
Claim 3
Dependent Claim
29 words
Process as claimed in claim 1, in which the said code is a binary code formed by a succession of pulses, each pulse having one of two different widths.
Claim 4
Dependent Claim
30 words
Process as claimed in claim 1, in which the code is a binary code, and the 0''s and 1''s of the code are formed by modulations at two different frequencies.
Claim 5
Dependent Claim
20 words
Process as claimed in claim 3, in which the said different frequencies are at about 10 percent from one another.
Claim 6
Independent Claim
113 words
A system for identifying a vehicle, comprising: an interrogation station comprising a transmitter for generating a frequency modulated continuous microwave, antenna means coupled to said transmitter, detector means, and demodulating means coupled to said detector means; and responder means on said vehicle comprising code modulation means, and means coupled to said code modulation means for receiving and supplying said continuous microwave to said code modulation means to be modulated with a periodic signal in accordance with a predetermined code characteristic of said vehicle, the modulation frequency of the continuous microwave being at least one thousand times the frequency of the periodic signal, and for returning the code modulated microwave to said interrogation station.
Claim 7
Independent Claim
113 words
A system for identifying a vehicle, comprising: an interrogation station comprising a transmitter for generating a frequency modulated continuous microwave, antenna means coupled to said transmitter, detector means, and demodulating means coupled to said detector means; and responder means on said vehicle comprising code modulation means, and means coupled to said code modulation means for receiving and supplying said continuous microwave to said code modulation means to be modulated with a periodic signal in accordance with a predetermined code characteristic of said vehicle, the modulation frequency of the continuous microwave being at least one thousand times the frequency of the periodic signal, and for returning the code modulated microwave to said interrogation station.
Claim 8
Dependent Claim
20 words
A system as claimed in claim 5, wherein said demodulating means includes two filter means tuned to respective different frequencies.
Claim 9
Dependent Claim
18 words
A system as claimed in claim 5, wherein said code modulation means is a binary code modulation means.
References Cited (Backward Citations)
US3353178A
Cited
US3384892A
Cited
FR1514341A
Cited
US3406391A
Cited
FR1517371A
Cited
US3521280A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1977-03-18 | 1977-09-17 | 1978-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-03-18 | 1981-09-17 | 1982-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-03-18 | 1985-09-17 | 1986-03-19 | $7700.00 | Window Closed / Lapsed |