US4231038A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doppler radar device
Assignee: US Philips Corp
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Filing: 1979-01-24
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Granted: 1980-10-28
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Expires: 1999-01-24
Abstract
Abstract A device for indicating whether a target is approaching or receding from a Doppler radar or the like comprising a length of wave-guide having a reflective termination at the end at which microwave energy is introduced into the guide, and two mixer diodes spaced along the guide. The diodes are spaced apart along the guide axis by an odd number of quarter-wavelengths and spaced from the termination by an odd number of eighth-wavelengths. Suitably, the diodes are positioned so as to be loosely-coupled to signals within the guide, thereby rendering the selection of suitable diodes much less critical.
Inventors
- 👤 Kenneth Holford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 04:22
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/06; G01S13/08; G01S13/32; H; H03; H03D; H03D9/00; H03D9/06; H03D9/0608; H03D9/0616
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
167 words
Apparatus for use in a Doppler radar or the like comprising a length of waveguide having a reflective termination at one end, means at said one end for introducing microwave energy into the waveguide and two mixer diodes arranged within and spaced apart along the waveguide so that energy to be transmitted can flow in one direction along the waveguide past the diodes to the other end of the waveguide and return energy reflected from a target can flow past the diodes in the opposite direction, the mixer diodes being spaced apart along the axis of the waveguide by a distance (2n+1)λ/4+γλ where n is zero or a positive integer, λ is the wavelength at the designed operating frequency and γ is a factor which compensates for the effect of the diodes on propagation within the guide and wherein the distance along the axis of the waveguide between the termination and the mixer diode nearer thereto is substantially (2m+1).λ/8 where m is zero or a positive integer.
Claim 2
Dependent Claim
167 words
Apparatus for use in a Doppler radar or the like comprising a length of waveguide having a reflective termination at one end, means at said one end for introducing microwave energy into the waveguide and two mixer diodes arranged within and spaced apart along the waveguide so that energy to be transmitted can flow in one direction along the waveguide past the diodes to the other end of the waveguide and return energy reflected from a target can flow past the diodes in the opposite direction, the mixer diodes being spaced apart along the axis of the waveguide by a distance (2n+1)λ/4+γλ where n is zero or a positive integer, λ is the wavelength at the designed operating frequency and γ is a factor which compensates for the effect of the diodes on propagation within the guide and wherein the distance along the axis of the waveguide between the termination and the mixer diode nearer thereto is substantially (2m+1).λ/8 where m is zero or a positive integer.
Claim 3
Dependent Claim
24 words
The apparatus as claimed in claim 1 wherein the diodes are positioned so as to be loosely coupled to the signals in the waveguide.
Claim 4
Dependent Claim
19 words
The apparatus as claimed in claim 2 wherein the diodes are positioned transversely from the axis of the waveguide.
Claim 5
Independent Claim
27 words
The apparatus as claimed in any preceding claim wherein the termination is a short circuit and said means includes a probe for introducing energy into the waveguide.
Claim 6
Independent Claim
27 words
The apparatus as claimed in any of claims 1, 2 or 3 wherein the termination is an iris through which energy can be introduced into the waveguide.
Claim 7
Dependent Claim
14 words
A device as claimed in claim 1 wherein γ is not more than 0.08.
Claim 8
Dependent Claim
9 words
A device as claimed in claim 1 wherein m=2.
Claim 9
Dependent Claim
9 words
A device as claimed in claim 1 wherein n=0.
References Cited (Backward Citations)
US3546633A
Cited
US3980974A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1983-10-28 | 1984-04-28 | 1984-10-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1987-10-28 | 1988-04-28 | 1988-10-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1991-10-28 | 1992-04-28 | 1992-10-28 | $7700.00 | Window Closed / Lapsed |