US3893113A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tracking receiver
Assignee: BBC Brown Boveri AG Switzerland
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Filing: 1973-12-18
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Granted: 1975-07-01
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Expires: 1993-12-18
Abstract
Abstract A tracking receiver particularly for use in the radar art for determining the frequency of Doppler signals in laser-Doppler flow probes includes a voltage-controlled oscillator the control voltage of which is varied during search operations until the frequency of the converted input signal comes to lie in the band pass of an intermediate frequency stage and so produces in a frequency discriminator a regulating voltage for the voltagecontrolled oscillator and with a threshold-value logic controlled by a peak-value detector connected to the intermediate-frequency stage for switching over the output of the frequency discriminator depending upon the intermediate frequency signal. Switching over of the frequency discriminator takes place only when the output signal from the intermediate frequency stage approaches the peak value of the output signal stored during the preceding search operation covering the whole tuning range of the receiver, or reaches a specific fraction of the peak value.
Inventors
- 👤 Paul D Iten
- 👤 Jiri Mastner
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 10:51
CPC Classifications
H; H03; H03J; H03J7/00; H03J7/18; H03J7/20; H03J7/24; H03J7/26; G; G01; G01S; G01S17/00; G01S17/02; G01S17/50
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
218 words
A tracking receiver comprising a mixer, a voltage-controlled oscillator having its output connected as one input to said mixer and the input signal connected as the other input to said mixer, an intermediate frequency stage having a pass band and which is connected to the output from said mixer, a frequency discriminator connected to the output from said intermediate frequency stage and which produces at its output a variable control voltage connected to said oscillator for varying the output frequency thereof during a search operation until the frequency of the output signal from said mixer comes to lie in the pass band of said intermediate frequency stage, an instantaneous-value detector connected to the output of said intermediate frequency stage, a peak-value detector also connected to the output of said intermediate frequency stage for storing the peak value of the output therefrom, a comparator for comparing the outputs from said instantaneous and peak-value detectors, and means including switching means disposed in the connection between the output from said frequency discriminator and said oscillator for switching over the discriminator when the instantaneous output signal from said intermediate frequency stage approaches or reaches a specific fraction of the peak value of its signal stored in said peak-value detector during the preceding search operation covering the whole tuning range of the receiver.
Claim 2
Dependent Claim
218 words
A tracking receiver comprising a mixer, a voltage-controlled oscillator having its output connected as one input to said mixer and the input signal connected as the other input to said mixer, an intermediate frequency stage having a pass band and which is connected to the output from said mixer, a frequency discriminator connected to the output from said intermediate frequency stage and which produces at its output a variable control voltage connected to said oscillator for varying the output frequency thereof during a search operation until the frequency of the output signal from said mixer comes to lie in the pass band of said intermediate frequency stage, an instantaneous-value detector connected to the output of said intermediate frequency stage, a peak-value detector also connected to the output of said intermediate frequency stage for storing the peak value of the output therefrom, a comparator for comparing the outputs from said instantaneous and peak-value detectors, and means including switching means disposed in the connection between the output from said frequency discriminator and said oscillator for switching over the discriminator when the instantaneous output signal from said intermediate frequency stage approaches or reaches a specific fraction of the peak value of its signal stored in said peak-value detector during the preceding search operation covering the whole tuning range of the receiver.
Claim 3
Dependent Claim
48 words
A tracking receiver as defined in claim 1 and wherein said means for switching over said frequency discriminator includes a logic connected between the output from said comparator and said switching means, said logic being controlled by the comparator output and by said control voltage of said oscillator.
Claim 4
Dependent Claim
34 words
A tracking receiver as defined in claim 1 and which further includes means deriving a control signal dependent upon the signal-to-noise ratio and means utilizing said control signal to also control said switching means.
Claim 5
Dependent Claim
78 words
A tracking receiver as defined in claim 3 wherein said means deriviNg a control signal dependent upon the signal-to-noise ratio comprises an integration network in which is stored the entire noise component of the input spectrum passing through said intermediate frequency stage and further comprising means for comparing a voltage corresponding to said stored noise with a voltage corresponding to the peak value of the output voltage of the intermediate frequency stage stored during the same search operation.
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) | 1978-06-30 | 1978-12-30 | 1979-07-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-06-30 | 1982-12-30 | 1983-07-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-06-30 | 1986-12-30 | 1987-07-01 | $7700.00 | Window Closed / Lapsed |