US3665321A
Expired / Lapsed
US
⏱️ 0.0 years remaining
System for passing on-frequency signals and for gating-out off-frequency signals
Assignee: Sierra Research Corp
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Filing: 1969-07-02
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Granted: 1972-05-23
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Expires: 1989-07-02
Abstract
Abstract A system for accepting signals of a desired frequency as well as undesired signals of other frequencies together therewith, examining the desired and undesired frequency components with regard to their intensities and using the results thereof to control gating means in the main receiver output path to pass signals whenever the relative levels of desired and undesired signal components fall within a satisfactory range. This determination is made by regulating a composite of both signal components to a constant level, and then comparing the level of a selected one of these components of the regulated composite with a preadjusted reference threshold level to derive a gate control signal.
Inventors
- 👤 Lewis Michnik
- 👤 William G Tapply
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:26
CPC Classifications
G; G01; G01S; G01S7/00; G01S7/02; G01S7/28; G01S7/285; G01S7/292; G01S7/2921; G01S7/36
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
275 words
A system having an input for accepting signals including onfrequency desired type components and off-frequency undesired type components, and said system being operative to pass signals to its output whenever the level of desired components relative to the undesired components is greater than an arbitrarily selected threshold and being operative to block the passage of signals to its output when the relative level is less, comprising: a. Main passband means coupled to said input and tuned to pass signals including said on-frequency components; b. Gate means connecting said main passband means to said output; c. Auxiliary passband means coupled to said input to accept said desired and undesired components and including means operative to regulate said accepted components and deliver to its own output composite signals whose magnitude is constant, and said auxiliary passband means further including filter means connected to accept said regulated output composite signals, to distinguish between desired-type and undesired-type frequency components and to pass one selected type of said components while blocking the other type of said components; and d. Reference level comparison means connected to the auxiliary passband means to receive said selected type components, said comparison means having means for establishing a reference level representing said arbitrary threshold and having means for comparing the level of the selected components with the reference level, and the comparison means having output control signals dependent upon the comparison of these levels and coupled to control said gate means to pass signals when the level of desired components relative to the undesired components as determined by said comparison is greater than said threshold and to block signals when the relative level is less.
Claim 2
Independent Claim
275 words
A system having an input for accepting signals including onfrequency desired type components and off-frequency undesired type components, and said system being operative to pass signals to its output whenever the level of desired components relative to the undesired components is greater than an arbitrarily selected threshold and being operative to block the passage of signals to its output when the relative level is less, comprising: a. Main passband means coupled to said input and tuned to pass signals including said on-frequency components; b. Gate means connecting said main passband means to said output; c. Auxiliary passband means coupled to said input to accept said desired and undesired components and including means operative to regulate said accepted components and deliver to its own output composite signals whose magnitude is constant, and said auxiliary passband means further including filter means connected to accept said regulated output composite signals, to distinguish between desired-type and undesired-type frequency components and to pass one selected type of said components while blocking the other type of said components; and d. Reference level comparison means connected to the auxiliary passband means to receive said selected type components, said comparison means having means for establishing a reference level representing said arbitrary threshold and having means for comparing the level of the selected components with the reference level, and the comparison means having output control signals dependent upon the comparison of these levels and coupled to control said gate means to pass signals when the level of desired components relative to the undesired components as determined by said comparison is greater than said threshold and to block signals when the relative level is less.
Claim 3
Dependent Claim
41 words
In a system as set forth in claim 1, said auxiliary passband including high gain amplifier means, and said regulating means together with said amplifier means having a composite passband which is very broad as compared with the main passband means.
Claim 4
Dependent Claim
73 words
In a system as set forth in claim 1, said filter means in the auxiliary passband comprising a notch filter tuned to reject on-frequency components whereby the output of the auxiliary passband means comprises the off-frequency component of the regulated composite signal, and said comparison means comparing the level of said off-frequency component with said reference level to obtain a control signal to block said gate means when the former exceeds the latter.
Claim 5
Dependent Claim
74 words
In a system as set forth in claim 1, said filter means in the auxiliary passband comprising a pass filter tuned to pass on-frequency components whereby the output of the auxiliary passband means comprises the on-frequency component of the regulated composite signal, and said comparison means compaRing the level of said on-frequency components with said reference level to obtain a control signal to render said gate means conductive when the former exceeds the latter.
Claim 6
Dependent Claim
51 words
In a system as set forth in claim 1, said system comprising a heterodyne receiver having frequency converter means and intermediate-frequency amplifier means, and said main passband means and auxiliary passband means being coupled in the receiver to accept output from the converter means, said on-frequency comprising the receiver intermediate frequency.
Claim 7
Dependent Claim
68 words
In a system as set forth in claim 1, said system being tunable to accept and pass any frequency within a band of selected on-frequencies and to reject off-frequencies having main energy spectra displaced from the selected on-frequency, and said system including means for tuning the main passband means to said selected on-frequency and means for tuning the filter means in the auxiliary passband means to track therewith.
Claim 8
Dependent Claim
31 words
In a system as set forth in claim 6, said main passband means and said filter means being voltage tunable circuits, and said tuning means including a scan-voltage generator coupled thereto.
Claim 9
Independent Claim
205 words
A system for receiving desired signals whose energy spectrum peaks up within a tuned passband and for rejecting spurious signals whose spectrum lacks an energy peak therewithin, comprising: a. Means for receiving a composite of both desired and spurious signal components, and including main passband means to accept and pass desired components of said signals; b. Gate means connecting said main passband means to an output of the system; c. Auxiliary passband means connected to said receiving means to receive said composite signals, and including automatic amplifier means for regulating its own output to a constant level upon receipt of a signal, and further including filter means tuned to accept said regulated output level and pass only spurious components of said output level; and d. Reference level comparison means having means for establishing a reference threshold level, and the comparison means being connected to said auxiliary means to receive said spurious components and compare their instantaneous levels with said threshold level, and having means responsive to the relative level of said spurious components as compared with said threshold level and operative to block said gate whenever the spurious component level exceeds said threshold level and to unblock the gate whenever the latter exceeds the former.
Claim 10
Independent Claim
205 words
A system for receiving desired signals whose energy spectrum peaks up within a tuned passband and for rejecting spurious signals whose spectrum lacks an energy peak therewithin, comprising: a. Means for receiving a composite of both desired and spurious signal components, and including main passband means to accept and pass desired components of said signals; b. Gate means connecting said main passband means to an output of the system; c. Auxiliary passband means connected to said receiving means to receive said composite signals, and including automatic amplifier means for regulating its own output to a constant level upon receipt of a signal, and further including filter means tuned to accept said regulated output level and pass only spurious components of said output level; and d. Reference level comparison means having means for establishing a reference threshold level, and the comparison means being connected to said auxiliary means to receive said spurious components and compare their instantaneous levels with said threshold level, and having means responsive to the relative level of said spurious components as compared with said threshold level and operative to block said gate whenever the spurious component level exceeds said threshold level and to unblock the gate whenever the latter exceeds the former.
Claim 11
Dependent Claim
38 words
In a system as set forth in claim 8, said automatic amplifier means having plural stages at least some of which are saturated by received signals having amplitudes above the minimum level for which the system is operative.
Claim 12
Dependent Claim
31 words
In a system as set forth in claim 8, said automatic amplifier means having automatic gain control means for adjusting the instantaneous level of the received signals to a constant value.
Claim 13
Dependent Claim
47 words
In a system as set forth in claim 8 for receiving pulses comprising bursts of high frequency energy, said automatic amplifier means having a time constant which is short as compared with the rise time of a pulse within the composite frequency range passed by the system.
Claim 14
Dependent Claim
115 words
In a system as set forth in claim 8, said receiving means including a mixer and local oscillator for changing the input signal frequencies to an intermediate frequency, and said auxiliary passband means operating upon said intermediate frequency and adjusting the instantaneous peak level of the signal components to be substantially constant, the main passband means and the auxiliary passband means including means respectively tuned to pass the desired signal and to pass a broad range of frequencies on both sides of but excluding the desired frequency; a main detector connected to the main passband means and to the gate; and an auxiliary detector connected to the auxiliary passband means and to the comparison means.
Claim 15
Dependent Claim
59 words
In a system as set forth in claim 12, said auxiliary passband means includIng a broad band filter whose bandwidth on each side of the main passband filter is very broad as compared with the bandwidth of the latter, and said broad band filter having a notch which is substantially co-extensive with the bandwidth of the main passband filter.
Claim 16
Dependent Claim
58 words
In a system as set forth in claim 8, said adjustable reference level in the comparison means comprising means for establishing an adjustable DC level which is less than the peak level to which said regulating means adjusts its output signal level, and means for comparing the instantaneous peak voltage of the spurious component with said DC level.
Claim 17
Independent Claim
135 words
The method of receiving and passing to an output desired signal components of one frequency and blocking spurious components of other frequencies which are also received therewith including the steps of: a. Taking a portion of the received composite components and adjusting the level of said portion of the components to a standardized value; b. Substantially separating said adjusted components; c. Comparing the level of one of the separated components with a preselected reference level whose magnitude represents a certain proportion of said standardized value to determine the ratio of said components; and d. Blocking the passage of said components to the output whenever the ratio of desired components to spurious components falls below said certain proportion and enabling the passage of said components to the output whenever said ratio is above said certain proportion.
Claim 18
Independent Claim
135 words
The method of receiving and passing to an output desired signal components of one frequency and blocking spurious components of other frequencies which are also received therewith including the steps of: a. Taking a portion of the received composite components and adjusting the level of said portion of the components to a standardized value; b. Substantially separating said adjusted components; c. Comparing the level of one of the separated components with a preselected reference level whose magnitude represents a certain proportion of said standardized value to determine the ratio of said components; and d. Blocking the passage of said components to the output whenever the ratio of desired components to spurious components falls below said certain proportion and enabling the passage of said components to the output whenever said ratio is above said certain proportion.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-05-23 | 1975-11-22 | 1976-05-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-05-23 | 1979-11-22 | 1980-05-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-05-23 | 1983-11-22 | 1984-05-23 | $7700.00 | Window Closed / Lapsed |