US3757329A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Systems for measuring velocities of moving bodies
Assignee: Toyota Motor Corp
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Filing: 1971-03-01
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Granted: 1973-09-04
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Expires: 1991-03-01
Abstract
Abstract In the system disclosed a random noise signal frequencymodulates a Doppler radar. More specifically the relative velocity between moving bodies or between a moving body and a fixed object is measured by transmitting an undulatory signal toward the body and receiving the reflected wave whose frequency has been shifted by the Doppler effect. The Doppler signal is detected by a homodyne detection system using a portion of the transmission signal as a reference. The transmitted undulatory signal exhibits frequency-modulation generated by a random noise signal. A portion of the frequency modulated undulatory wave is used as a reference. The frequency modulation by the random noise prevents erroneous operation caused by interference between different transmitted undulatory signals.
Inventors
- 👤 K Sato
- 👤 H Watanabe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 06:08
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/88; G01S13/91; G01S13/92
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
104 words
A velocity measuring system, comprising energy generating means for continuously transmitting undulatory waves from one position and receiving object-reflected undulatory waves at a position fixed relative to the one position, frequency comparator means responsive to said generating means for combining the frequency of the transmitted wave with the frequency of the received wave to form a Doppler signal as a measure of velocity, and exclusion means for identifying the transmitted undulatory waves so as to exclude velocity measurement with extrAneous signals, said exclusion means including modulating means forming a part of said generating means for continuously modulating the transmitted signal on a random basis.
Claim 2
Dependent Claim
104 words
A velocity measuring system, comprising energy generating means for continuously transmitting undulatory waves from one position and receiving object-reflected undulatory waves at a position fixed relative to the one position, frequency comparator means responsive to said generating means for combining the frequency of the transmitted wave with the frequency of the received wave to form a Doppler signal as a measure of velocity, and exclusion means for identifying the transmitted undulatory waves so as to exclude velocity measurement with extrAneous signals, said exclusion means including modulating means forming a part of said generating means for continuously modulating the transmitted signal on a random basis.
Claim 3
Dependent Claim
22 words
A system as in claim 1, wherein said modulating means include frequency changing means for modulating the frequency of the transmitted signal.
Claim 4
Dependent Claim
25 words
A system as in claim 2, wherein said modulating means include limiting means for limiting the frequency range of the modulation of the transmitted signal.
Claim 5
Dependent Claim
41 words
A system as in claim 1, wherein said modulating means include random signal generating means having band-pass filter means for controlling the frequency output of said random generating means, and a modulator responsive to the output of said band-pass filter means.
Claim 6
Dependent Claim
22 words
A system as in claim 1, wherein said comparator means includes low-pass filter means for limiting the frequency of the Doppler signal.
Claim 7
Dependent Claim
72 words
A system as in claim 5, wherein said generating means include oscillator means for forming an alternating signal; wherein said modulating means includes random signal forming means for forming random signals, band-pass filter means for limiting the frequency range of the random signals, and a modulator responsive to said band-pass filter means and connected to said generator means for modulating the transmitted signal over a frequency range determined by said band-pass filter.
Claim 8
Dependent Claim
123 words
A velocity measuring system, comprising oscillator means for generating an undulating wave signal, frequency modulating means responsive to said oscillator means for randomly frequency-modulating the wave signal by a random noise signal which varies between predetermined frequencies, transmitting and receiving means coupled to said frequency modulating means for transmitting the frequency-modulated wave signal toward an oncoming object and for receiving the wave signal reflected by said oncoming object so that the wave signal received is a Doppler shifted, and homodyne detecting means coupled to said transmitting and receiving means for mixing the part of the transmitted wave signal as a reference signal with the reflected wave signal and detecting the frequency shift as a measure of the relative velocity of the oncoming object.
Claim 9
Dependent Claim
123 words
A velocity measuring system, comprising oscillator means for generating an undulating wave signal, frequency modulating means responsive to said oscillator means for randomly frequency-modulating the wave signal by a random noise signal which varies between predetermined frequencies, transmitting and receiving means coupled to said frequency modulating means for transmitting the frequency-modulated wave signal toward an oncoming object and for receiving the wave signal reflected by said oncoming object so that the wave signal received is a Doppler shifted, and homodyne detecting means coupled to said transmitting and receiving means for mixing the part of the transmitted wave signal as a reference signal with the reflected wave signal and detecting the frequency shift as a measure of the relative velocity of the oncoming object.
Claim 10
Dependent Claim
24 words
An apparatus as in claim 7, wherein said homodyne detecting means includes low pass filter means for limiting the frequency of the Doppler signal.
Claim 11
Dependent Claim
36 words
A system as in claim 7, wherein said frequency modulating means includes noise generator means, and band-pass filter means coupled to said noise generator means for establishing the predetermined frequencies between which the noise signal varies.
Claim 12
Dependent Claim
20 words
An apparatus as in claim 9, wherein said frequency modulating means includes a modulator responsive to said band-pass filter means.
References Cited (Backward Citations)
US3212083A
Cited
US3474444A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-09-03 | 1977-03-05 | 1977-09-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-09-03 | 1981-03-05 | 1981-09-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-09-03 | 1985-03-05 | 1985-09-04 | $7700.00 | Window Closed / Lapsed |