US3805262A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Transmission antenna mixer doppler motion detection
Assignee: Johnson Service Co
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Filing: 1972-07-03
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Granted: 1974-04-16
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Expires: 1992-07-03
Abstract
Abstract An intrusion Doppler motion detector detects the motion of a human intruder into a selected volumetric space. An oscillator of the avalanche or IMPATT diode type operating above 5GHz is mounted within an oscillator cavity and establishes and transmitts an RF field to a separate mixer cavity which also functions as a transmitting waveguide for feeding a common transmitting and receiving antenna. A separate mixer diode is coupled to the mixer cavity and thereby exposed to both the transmitted and the echo signal to produce a Doppler frequency output signal. A signal processing circuit is connected to the mixer diode and actuates an alarm in response to the Doppler signal.
Inventors
- 👤 C Klein
- 👤 A Giovanelli
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 21:20
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/50; G01S13/52; G01S13/56
Claims Analysis
Total Claims: 13
Claim 1
Independent Claim
79 words
A low powered Doppler motion detection apparatus for detection of intrusion into a limited space adjacent the apparatus, comprising a microwave oscillator means including a transmitting cavity means, a mixer-detector waveguide cavity means, a reduce height waveguide impedance transformer connecting said waveguide cavity means to the transmitting cavity means, a common transmitting and receiving antenna connected to the mixerdetection waveguide cavity means, and a mixer solid state means having a non-linear characteristic coupled to said mixerdetection waveguide cavity means.
Claim 2
Dependent Claim
79 words
A low powered Doppler motion detection apparatus for detection of intrusion into a limited space adjacent the apparatus, comprising a microwave oscillator means including a transmitting cavity means, a mixer-detector waveguide cavity means, a reduce height waveguide impedance transformer connecting said waveguide cavity means to the transmitting cavity means, a common transmitting and receiving antenna connected to the mixerdetection waveguide cavity means, and a mixer solid state means having a non-linear characteristic coupled to said mixerdetection waveguide cavity means.
Claim 3
Dependent Claim
54 words
The Doppler motion detection apparatus of claim 1 wherein said waveguide cavity means is constructed to establish coupling impedances between said mixer means and said antenna and between said mixer means and said oscillator means to create a minimum transmitter voltage standing wave ratio and a relatively large received signal at the mixer means.
Claim 4
Dependent Claim
65 words
The low powered Doppler motion detection apparatus of claim 1 wherein said mixer means is a diode means coupled to said mixer-detection waveguide cavity and said waveguide cavity means is constructed to establish coupling impedances to create a minimum transmitter voltage standing wave ratio and said diode means is located relative to said antenna to establish a relatively large received signal at the diode means.
Claim 5
Dependent Claim
18 words
The Doppler motion detection apparatus of claim 3 wherein said mixer diode means is mounted within the cavity.
Claim 6
Dependent Claim
23 words
The Doppler motion detection apparatus of claim 3 wherein said mixer diode means is coupled to said waveguide cavity means by a probe.
Claim 7
Dependent Claim
48 words
The Doppler motion detection apparatus of claim 1 having an amplification means connected to said mixer means to amplify the Doppler motion signal, a level detector connected to said amplification means to respond to signals of a predetermined minimum level, and alarm means connected to said level detector.
Claim 8
Dependent Claim
34 words
The Doppler motion detection apparatus of claim 1 wherein said oscillator means includes an oscillator diode means mounted within said transmitting cavity and connected to a power supply means for creating said microwave energy.
Claim 9
Dependent Claim
123 words
The low powered Doppler motion detection apparatus of claim 1 wherein said microwave oscillator means includes an oscillator diode means mounted within said transmitting cavity means and connected to a power supply means for creating said microwave energy, said mixer means is a diode means mounted coupled to said mixer-detection waveguide cavity means, said waveguide cavity means being constructed to create a minimum transmitter voltage standing ratio wave and said diode means being located to establish a maximum received signal at the diode means, amplification means connected to said mixer diode means to amplify the Doppler motion signal, a level detector connected to said amplification means to respond to signals of a predetermined minimum level, and alarm means connected to said level detector.
Claim 10
Dependent Claim
102 words
A low powered Doppler motion detection apparatus for detection of intrusion into a limited space adjacent the apparatus, comprising a coaxial cavity oscillator including an open end coaxial line within a transmitting cavity means, said cavity means haVing a transmitting iris in the sidewall thereof, a reduced height waveguide impedance transformer extending from said iris, a mixer-detection waveguide cavity means extending outwardly from said transformer and terminating in a common transmitting and receiving antenna means, and a mixing means having a non-linear characteristic coupled to the mixer-detection waveguide cavity means to produce an output signal in accordance with received Doppler motion signals.
Claim 11
Dependent Claim
102 words
A low powered Doppler motion detection apparatus for detection of intrusion into a limited space adjacent the apparatus, comprising a coaxial cavity oscillator including an open end coaxial line within a transmitting cavity means, said cavity means haVing a transmitting iris in the sidewall thereof, a reduced height waveguide impedance transformer extending from said iris, a mixer-detection waveguide cavity means extending outwardly from said transformer and terminating in a common transmitting and receiving antenna means, and a mixing means having a non-linear characteristic coupled to the mixer-detection waveguide cavity means to produce an output signal in accordance with received Doppler motion signals.
Claim 12
Dependent Claim
37 words
The low powered Doppler motion detection apparatus of claim 9 including an aperture screw selectively positioned within said transformer immediately adjacent the iris to control the coupling between the transmitting cavity means and the waveguide cavity means.
Claim 13
Dependent Claim
62 words
The low powered Doppler motion detection apparatus of claim 9 including a detection probe unit having a central conductor mounted in insulated relationship within an outer wall and extending inwardly into the waveguide cavity means, a mixing diode mounted in insulated relationship within the probe unit and connected in series between the central probe and the outer wall of the probe unit.
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) | 1977-04-15 | 1977-10-15 | 1978-04-16 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-04-15 | 1981-10-15 | 1982-04-16 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-04-15 | 1985-10-15 | 1986-04-16 | $7700.00 | Window Closed / Lapsed |