US3781706A
Expired / Lapsed
US
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Incremental phase shift frequency synthesizer
Assignee: United States Department of the Navy
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Filing: 1972-08-04
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Granted: 1973-12-25
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Expires: 1992-08-04
Abstract
Abstract Apparatus for synthesizing an adjusted reference signal at a frequency that is controllable to a prescribed value performs the programmed addition (or subtraction) of sequential incrementation of phase shift to the reference signal output of an undisturbed oscillator that has a characteristic frequency of oscillation that is accurately predictable for a significant time period into the future. Purposes of the proposed apparatus include (a) the generation and maintaining of small offsets in the frequency of the adjusted output reference signal relative to the nominal or actual frequency of the oscillator, (b) the compensation for the time dependent predictable drift of the source oscillator to maintain the adjusted output signal at the desired frequency even though the source oscillator frequency changes, (c) the operation of precise time and frequency systems with complete coherency between the modulation representing timing and the RF carrier representing frequency, and (d) the ability to calibrate, adjust, and normalize the timing of a clock system operating from the adjusted reference signal both as to location of its epoch(s) and its scale relative to an accepted system primary standard of time.
Inventors
- 👤 E Osborne
- 👤 T Mcgovern
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 15:09
CPC Classifications
H; H03; H03H; H03H7/00; H03H7/18; H03H7/21; G; G01; G01S; G01S11/00; G01S11/02; H03B; H03B21/00; H03H11/00; H03H11/02; H03H11/16; H03H11/22; H03H17/00; H03H17/08; H03L; H03L7/00; H03L7/06; H03L7/08; H03L7/099; H03L7/0991; H03L7/0992
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
300 words
Apparatus for producing from an input signal of frequency f1 a normalized output signal at a specified reference frequency fr comprising, a signal of preselected frequency, frequency divider means connected to receive said signal of preselected frequency, control means responsive to control data operably connected to control said frequency divider means to divide down said preselected frequency to produce a lower frequency signal, incremental phase shift means connected to receive said input signal at frequency f1 and responsive to lower frequency signal from said frequency divider means for imparting incremental phase shifts to said input signal at a rate determined by said lower frequency signal to produce an incrementally phase shifted signal at the specified reference frequency fr, and band-pass filter means Having a pass band centered at said specified reference frequency fr operably connected to said incremental phase shift means for filtering said incrementally phase shifted signal, said frequency divider means including, a command controlled register means having multiple bit storage positions for stroing in binary bit form a digital count selected by said control data representing the desired frequency value of said lower frequency signal, a variable frequency dividing counter means operably connecting said signal of preselected frequency to said incremental phase shift means and having multiple bit counting positions equal in number to the multiple bit storage positions of said command controlled register means, means operably connected to said variable frequency dividing counter means and said command controlled register means for performing a bit-by-bit comparison of the bit positions of said counter means and said registering means, and means responsive to said comparison means for repetitively resetting said counter means to a zero count condition each time correspondence is detected by said comparison means between all corresponding bit positions in said counter means and said registering means.
Claim 2
Dependent Claim
300 words
Apparatus for producing from an input signal of frequency f1 a normalized output signal at a specified reference frequency fr comprising, a signal of preselected frequency, frequency divider means connected to receive said signal of preselected frequency, control means responsive to control data operably connected to control said frequency divider means to divide down said preselected frequency to produce a lower frequency signal, incremental phase shift means connected to receive said input signal at frequency f1 and responsive to lower frequency signal from said frequency divider means for imparting incremental phase shifts to said input signal at a rate determined by said lower frequency signal to produce an incrementally phase shifted signal at the specified reference frequency fr, and band-pass filter means Having a pass band centered at said specified reference frequency fr operably connected to said incremental phase shift means for filtering said incrementally phase shifted signal, said frequency divider means including, a command controlled register means having multiple bit storage positions for stroing in binary bit form a digital count selected by said control data representing the desired frequency value of said lower frequency signal, a variable frequency dividing counter means operably connecting said signal of preselected frequency to said incremental phase shift means and having multiple bit counting positions equal in number to the multiple bit storage positions of said command controlled register means, means operably connected to said variable frequency dividing counter means and said command controlled register means for performing a bit-by-bit comparison of the bit positions of said counter means and said registering means, and means responsive to said comparison means for repetitively resetting said counter means to a zero count condition each time correspondence is detected by said comparison means between all corresponding bit positions in said counter means and said registering means.
Claim 3
Dependent Claim
16 words
The apparatus specified in claim 1 wherein said signal of preselected frequency is said input signal.
Claim 4
Dependent Claim
86 words
The apparatus specified in claim 1 wherein said incremental phase shift means includes, a plurality of phase shift means each capable of imparting a predetermined different amount of phase shift to said input signal, and commutating control means operably connected to receive said lower frequency signal for sequentially interconnecting selectively said plurality of phase shift means between said input signal and said filter means at a rate determined by said lower frequency signal, whereby said reference frequency depends on the frequency of said lower frequency signal.
Claim 5
Dependent Claim
68 words
The apparatus specified in claim 1 wherein said incremental phase shift means comprises circuit means for producing a plurality of signals each being incrementally displaced in phase relative to said input signal by progressively increasing amounts which range from 0360*/n , . . . (n - 1)/n 360*, where n is the desired number of phase steps or increments into which said input signal is to be incremented.
Claim 6
Dependent Claim
102 words
The apparatus specified in claim 4 wherein said circuit means includes, means connected to receive said input signal for producing output signals representing respectively said input signal displaced by 0*, 90*, 180*and 270*, and a four quadrant potentiometer means each quadrant of which is connected between quadrature displaced pairs of said 0*, 90*, 180* and 270* displaced signals and including resistive means effictive to subdivide each quadrant of said potentiometer into n nodes at which appears the plurality of signals incrementally displaced in phase relatively to said input signal within the range 0*, 360*/n , . . . (n - 1)/n 360*.
Claim 7
Dependent Claim
51 words
The apparatus specified in claim 4 wherein said circuit means for producing said plurality of phase displaced signals includes a multiple tapped delay line connected to receive said input signal and capable of producing at its multiple taps said plurality of signals increasing displaced in phase relative to said input signal.
Claim 8
Dependent Claim
27 words
The apparatus specified in claim 4 further including means for sequentially commutating the plurality of signals produced by said incremental phase shift means to said filter means.
Claim 9
Dependent Claim
42 words
The apparatus specified in claim 7 wherein said sequential commutator means operates at a rate determined by said lower frequency, whereby the cumulative phase shift imparted to said input signal by said incremental phase shift means is dependent upon said lower frequency.
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) | 1976-12-24 | 1977-06-25 | 1977-12-25 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-12-24 | 1981-06-25 | 1981-12-25 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-12-24 | 1985-06-25 | 1985-12-25 | $7700.00 | Window Closed / Lapsed |