US3863253A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multiple frequency doppler radar system for vehicle passengers
Assignee: Nissan Motor Co Ltd
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Filing: 1973-05-25
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Granted: 1975-01-28
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Expires: 1993-05-25
Abstract
Abstract A multiple frequency doppler radar system for a vehicle passenger which detects a distance between the vehicle and an object in the vehicle path by transmitting two signals differing only slightly in frequency in advance of contact of the vehicle with the object, which is characterized by means for converting the doppler signals corresponding to the transmitted two signals into two rectangular signals, an exclusive OR gate which receives the two rectangular signals for producing pulses each appearing at a time period when either of the rectangular signals appears, and means for averaging the pulses from the exclusive OR gate so as to produce a distance signals representing the distance between the vehicle and the object.
Inventors
- 👤 Masami Kiyoto
- 👤 Makoto Anzai
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 18:06
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88; G01S13/93; G01S13/931; G01S13/02; G01S13/06; G01S13/08; G01S13/10; G01S13/103; G01S13/24; G01S13/32; G01S13/34; G01S13/348
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
122 words
In a doppler radar system for a vehicle which detects a distance between the vehicle and an object in the vehicle path by transmitting two separate signals differing only slightly in frequency, the improvement comprises: first means for converting each of the doppler signals corresponding to the transmitted separate two signals into a pulse signal consisting of pulses appearing during alternative half waves of said each of the doppler signals; second means for producing a pulse train consisting of a plurality of pulses each appearing at a time period when either one of the two pulse signals appears; and third means for averaging said pulse train so as to produce a distance signal representing the distance between the vehicle and the object.
Claim 2
Dependent Claim
122 words
In a doppler radar system for a vehicle which detects a distance between the vehicle and an object in the vehicle path by transmitting two separate signals differing only slightly in frequency, the improvement comprises: first means for converting each of the doppler signals corresponding to the transmitted separate two signals into a pulse signal consisting of pulses appearing during alternative half waves of said each of the doppler signals; second means for producing a pulse train consisting of a plurality of pulses each appearing at a time period when either one of the two pulse signals appears; and third means for averaging said pulse train so as to produce a distance signal representing the distance between the vehicle and the object.
Claim 3
Dependent Claim
32 words
The invention as claimed in claim 1, in which said first means includes amplifying means for amplifying said doppler signals, and limit means for limitting the amplitudes of the amplified doppler signals.
Claim 4
Dependent Claim
44 words
The invention as claimed in claim 2, in which said limit means adapted to produce a pulse rising up when the intensity of the input signal exceeds a predetermined value and falling down when the intensity of the input signal lowers a predetermined value.
Claim 5
Dependent Claim
23 words
The invention as claimed in claim 1, in which said second means includes an exclusive OR gate means connected to said first means.
Claim 6
Dependent Claim
27 words
The invention as claimed in claim 1, in which said third means includes an integrator consisting of a resistor and a capacitor serially connected to said resistor.
Claim 7
Dependent Claim
34 words
The invention as claimed in claim 1, which further comprises: fourth means for disabling said third means when one pulse of said pulse train from said second means lasts over a predetermined time period.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-01-27 | 1978-07-29 | 1979-01-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-01-27 | 1982-07-29 | 1983-01-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-01-27 | 1986-07-29 | 1987-01-28 | $7700.00 | Window Closed / Lapsed |