US3634860A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Doppler radar with target velocity direction and range indication, utilizing a variable-frequency generator
Assignee: United States Department of the Army
•
Filing: 1970-01-21
•
Granted: 1972-01-11
•
Expires: 1990-01-21
Abstract
Abstract The energy output from the CW oscillator of this radar is periodically phase shifted plus and minus 22.5* under the control of the output of a variable frequency square wave generator. The echo signals are combined with a sample of the transmitted signals and applied to a single mixer. A pair of Doppler signals are sequentially derived from the mixer output by means of a gate circuit operated by the square wave generator. At a certain generator frequency which depends on target range, the relative phases of the two Doppler signals will indicate the sense of direction of target movement. The generator frequencyadjusting means can be calibrated in terms of target range.
Inventors
- 👤 Otto E Rittenbach
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 04:50
CPC Classifications
G; G01; G01S; G01S13/00; G01S13/02; G01S13/50; G01S13/58; G01S13/62; G01S13/06; G01S13/08; G01S13/32; G01S13/325
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
176 words
A Doppler radar set with target directivity and range measurement capability, comprising, a continuous wave oscillator for generating the energy to be transmitted, a two-state plus and minus 22.5* phase shifter connected to the output of said oscillator, an adjustable frequency square wave generator connected to said phase shifter to periodically change the state of the phase shifter, means connected to the output of said phase shifter for transmitting the phase shifted energy to an antenna and to receive echoes of the transmitted energy and to provide an output of superimposed echoes of the transmitted signal and a sample of the transmitted signal, a mixer connected to the output of said means to derive a signal which changes phase by 90* at the frequency of said square wave generator, and a double-output gate connected to the output of said mixer and to said square wave generator for sequentially applying the two phases of the output of said mixer to a pair of Doppler channels respectively under the control of the output of said square wave generator.
Claim 2
Dependent Claim
176 words
A Doppler radar set with target directivity and range measurement capability, comprising, a continuous wave oscillator for generating the energy to be transmitted, a two-state plus and minus 22.5* phase shifter connected to the output of said oscillator, an adjustable frequency square wave generator connected to said phase shifter to periodically change the state of the phase shifter, means connected to the output of said phase shifter for transmitting the phase shifted energy to an antenna and to receive echoes of the transmitted energy and to provide an output of superimposed echoes of the transmitted signal and a sample of the transmitted signal, a mixer connected to the output of said means to derive a signal which changes phase by 90* at the frequency of said square wave generator, and a double-output gate connected to the output of said mixer and to said square wave generator for sequentially applying the two phases of the output of said mixer to a pair of Doppler channels respectively under the control of the output of said square wave generator.
Claim 3
Dependent Claim
229 words
In a Doppler radar set with target directivity and range measurement capability of the type that includes an antenna for emitting signal energy and for intercepting echoes of the emitted signal energy, a mixer, a double-output gate connected to the output of the mixer and having two operating states for delivering the mixer output alternately to a pair of Doppler channels, a circulator for transmitting signal energy to the antenna and to receive echoes of the transmitted signal and to deliver a sample of the transmitted signal and the signal echoes returned through the antenna to the input of the mixer, means for generating continuous wave signal energy, a phase shifter connected to the output of the signal generating means and coupling the signal energy to the circulator and having two operating states in which the respective signal energies delivered to the circulator have a fixed phase difference and means for shifting states of the phase shifter and of the double-output gate in a predetermined relationship, the improvement therein which comprises said state shifting means being operable to shift states of the phase shifter and the double-output gate in synchronism with equal time intervals in each state and selectively adjustable to change the lengths of the time intervals, and said phase shifter being of the type for delivering outputs in the two states that differ in phase by 45*.
Claim 4
Dependent Claim
229 words
In a Doppler radar set with target directivity and range measurement capability of the type that includes an antenna for emitting signal energy and for intercepting echoes of the emitted signal energy, a mixer, a double-output gate connected to the output of the mixer and having two operating states for delivering the mixer output alternately to a pair of Doppler channels, a circulator for transmitting signal energy to the antenna and to receive echoes of the transmitted signal and to deliver a sample of the transmitted signal and the signal echoes returned through the antenna to the input of the mixer, means for generating continuous wave signal energy, a phase shifter connected to the output of the signal generating means and coupling the signal energy to the circulator and having two operating states in which the respective signal energies delivered to the circulator have a fixed phase difference and means for shifting states of the phase shifter and of the double-output gate in a predetermined relationship, the improvement therein which comprises said state shifting means being operable to shift states of the phase shifter and the double-output gate in synchronism with equal time intervals in each state and selectively adjustable to change the lengths of the time intervals, and said phase shifter being of the type for delivering outputs in the two states that differ in phase by 45*.
Claim 5
Dependent Claim
40 words
The radar set defined in claim 2 wherein said phase shiFter is a plus and minus 22.5* phase shifter and said state shifting means is a square wave generator delivering its output to said phase shifter and said double-output gate.
References Cited (Backward Citations)
US3422430A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-01-10 | 1975-07-12 | 1976-01-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-01-10 | 1979-07-12 | 1980-01-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-01-10 | 1983-07-12 | 1984-01-11 | $7700.00 | Window Closed / Lapsed |