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US4137505A Expired / Lapsed US ⏱️ 0.0 years remaining

Method of and apparatus for frequency control

Assignee: Patelhold Patenverwertungs and Elektro-Holding AG
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Filing: 1976-04-08
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Granted: 1979-01-30
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Expires: 1996-04-08
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Abstract

Abstract Method and apparatus for demodulation of a phase shift keyed carrier in which a plurality of auxiliary signal frequency sources are provided and a substantially constant phase difference is maintained therebetween. Each auxiliary signal frequency is mixed with the modulated carrier and the mixer outputs are combined to form the product thereof to yield a control signal for regulating the auxiliary.

Inventors

  • 👤 Gustav Guanella

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 10:25
CPC Classifications
H; H03; H03L; H03L7/00; H03L7/06; H03L7/08; H03L7/085; H03L7/087; H04; H04L; H04L27/00; H04L27/18; H04L27/22; H04L27/227; H04L27/2271; H04L27/2273; H04L27/0014; H04L2027/0016

Claims Analysis

Total Claims: 37
Claim 1
Independent Claim 156 words
A demodulator for a phase keyed carrier comprising: means for providing first and second frequency signals having a substantially constant phase difference therebetween; first means for mixing the modulated carrier with one of said first and second signals; second means for mixing the modulated carrier with the remaining one of said first and second frequency signal; means for combining the outputs of said first and second mixers for generating a control signal coupled to said providing means for regulating at least one of said first and second frequency signals product-forming means for forming the products of the outputs of said first and second mixer means; said means for combining further including a sum-forming circuit coupled between said first and second mixers and said combining means and a difference-forming circuit coupled between said first and second mixers and said combining means to respectively couple the sums and the differences of the mixer outputs to said product-forming means.
Claim 2
Dependent Claim 156 words
A demodulator for a phase keyed carrier comprising: means for providing first and second frequency signals having a substantially constant phase difference therebetween; first means for mixing the modulated carrier with one of said first and second signals; second means for mixing the modulated carrier with the remaining one of said first and second frequency signal; means for combining the outputs of said first and second mixers for generating a control signal coupled to said providing means for regulating at least one of said first and second frequency signals product-forming means for forming the products of the outputs of said first and second mixer means; said means for combining further including a sum-forming circuit coupled between said first and second mixers and said combining means and a difference-forming circuit coupled between said first and second mixers and said combining means to respectively couple the sums and the differences of the mixer outputs to said product-forming means.
Claim 3
Dependent Claim 143 words
Apparatus for the demodulation of a phase-keyed high frequency signal w comprising, in combination: variable frequency means for producing first and second auxiliary high frequency signals h 1 and h 2 ; phase-shift means connected to said variable frequency means for producing a phase shift between said first and second signals h 1 and h 2 ; first and second mixer circuit means each receiving, as inputs, said high frequency signal w and said auxiliary high frequency signals h 1 and h 2 respectively, and producing output signals a and b respectively; product forming circuit means for producing a control signal r having a value related to a b (b 2 -a 2 ); and means connecting said control signal r to said variable frequency means and varying the output frequencies h 1 and h 2 in accordance with said control signal r.
Claim 4
Dependent Claim 143 words
Apparatus for the demodulation of a phase-keyed high frequency signal w comprising, in combination: variable frequency means for producing first and second auxiliary high frequency signals h 1 and h 2 ; phase-shift means connected to said variable frequency means for producing a phase shift between said first and second signals h 1 and h 2 ; first and second mixer circuit means each receiving, as inputs, said high frequency signal w and said auxiliary high frequency signals h 1 and h 2 respectively, and producing output signals a and b respectively; product forming circuit means for producing a control signal r having a value related to a b (b 2 -a 2 ); and means connecting said control signal r to said variable frequency means and varying the output frequencies h 1 and h 2 in accordance with said control signal r.
Claim 5
Dependent Claim 47 words
Apparatus in accordance with claim 2 wherein the output signals of the mixers are applied to the product forming circuit on the one hand directly and on the other hand by way of at least one sum-forming circuit and by way of at least one difference-forming circuit.
Claim 6
Dependent Claim 20 words
Apparatus in accordance with claim 2 wherein the input signals applied to the product forming circuit are limited in amplitude.
Claim 7
Dependent Claim 37 words
Apparatus in accordance with claim 2 wherein the product-forming circuit is comprised of a switching circuit, the constant amplitude output signal of which has a sign corresponding to the product of the signs of the input signals.
Claim 8
Dependent Claim 40 words
Apparatus in accordance with claim 2 wherein the output signal of the product-forming circuit is applied to a low-pass filter for the suppression of rapid fluctuations and the output signal of this filter is applied to control the generator frequency.
Claim 9
Independent Claim 155 words
The method of demodulating a phase-keyed high frequency signal w having a given number n of possible keying conditions, comprising the steps of: producing at least first and second auxiliary high frequency signals h 1 and h 2 , respectively, having the same frequency and having a constant phase difference; mixing said phase-keyed high frequency signal w with said first and second high frequency signals respectively to produce respective difference frequency signals a and b; producing an output control signal r for controlling the frequency of said first and second auxiliary high frequency signals h 1 and h 2 by producing, from the vector voltage V k of the signal, its involute V k n , and deriving said control signal from one component of said involute vector V k n ; and varying said frequency of said signals h 1 and h 2 in accordance with the variation of said output control signal r.
Claim 10
Independent Claim 155 words
The method of demodulating a phase-keyed high frequency signal w having a given number n of possible keying conditions, comprising the steps of: producing at least first and second auxiliary high frequency signals h 1 and h 2 , respectively, having the same frequency and having a constant phase difference; mixing said phase-keyed high frequency signal w with said first and second high frequency signals respectively to produce respective difference frequency signals a and b; producing an output control signal r for controlling the frequency of said first and second auxiliary high frequency signals h 1 and h 2 by producing, from the vector voltage V k of the signal, its involute V k n , and deriving said control signal from one component of said involute vector V k n ; and varying said frequency of said signals h 1 and h 2 in accordance with the variation of said output control signal r.
Claim 11
Dependent Claim 18 words
The method of claim 7 wherein said signals a and b are phase-shifted from one another by 90°.
Claim 12
Dependent Claim 22 words
The method of claim 8 wherein said control signal r follows the form of a b (b 2 - a 2 ).
Claim 13
Dependent Claim 33 words
The method of claim 9 wherein said control signal r is produced by circuit means for producing the difference (b-a) and the sum (b+a) and by producing the product of a b (b-a)(b+a).
Claim 14
Dependent Claim 39 words
The method of claim 9 which includes the steps of squaring the signals a and b respectively, and then taking the difference of (b 2 -a 2 ) and multiplying said difference by the product of a and b.
Claim 15
Dependent Claim 46 words
The method in accordance with claim 9 wherein from said signals a and b there are derived the sum signal (b + a) and the difference signal (b - a) and to form the control signal the product of a, b, (b+a) and (b-a) is produced.
Claim 16
Dependent Claim 58 words
The method in accordance with claim 8 wherein from signals a and b there are derived the sum signals (b +√3 a), (√3 b + a) and also the difference signals (b -3√a), (√3 b - a) and to form the control signal the product of the signals a, b and these sum and difference signals are produced.
Claim 17
Dependent Claim 74 words
The method in accordance with claim 8 wherein from said signals a and b there are derived the sum signals (b + a), [b + (√2 + a)a], [b + √2 - 1)a] and also the difference signals (b - a), [b - (√2 + 1)a], [b - (√2 - 1) a] and the control signals is formed by the product of the signals a, b and these sum and difference signals are produced.
Claim 18
Dependent Claim 45 words
The method in accordance with claim 7 wherein at least three further signals are derived by mixing the phase keyed high frequency oscillation with at least three auxiliary oscillations of unlike phase, the control signal being produced by forming the product of said further signals.
Claim 19
Dependent Claim 35 words
The method in accordance with claim 15 wherein three said further signals are derived by mixing the phase keyed high frequency oscillation with three auxiliary oscillations differing in phase by π/3 or integral multiples thereof.
Claim 20
Dependent Claim 35 words
The method in accordance with claim 15 wherein four said further signals are derived by mixing the phase keyed high frequency oscillation with four auxiliary oscillations differing in phase by π/4 or integral multiples thereof.
Claim 21
Dependent Claim 35 words
The method in accordance with claim 15 wherein six said further signals are derived by mixing the phase keyed high frequency oscillation with six auxiliary oscillations differing in phase by π/6 or integral multiples thereof.
Claim 22
Dependent Claim 35 words
The method in accordance with claim 15 wherein eight said further signals are derived by mixing the phase keyed high frequency oscillation with eight auxiliary oscillations differing in phase by π/8 or integral multiples thereof.
Claim 23
Dependent Claim 45 words
The method in accordance with claim 15 wherein n said further signals are derived by mixing the phase keyed high frequency oscillation with n auxiliary oscillations differing in phase by π/n or integral multiples thereof, where n = 2, 3, 4, . . . ,n.
Claim 24
Dependent Claim 39 words
The method in accordance with claim 7 wherein said output control signal r consists of a signal of constant amplitude of which the sign varies in accordance with the product of the signs of the signals a and b.
Claim 25
Dependent Claim 27 words
The method in accordance with claim 7 wherein said signals a and b and the signals formed therefrom are amplitude limited before being used for product formation.
Claim 26
Dependent Claim 20 words
The method in accordance with claim 15 wherein said further signals are amplitude limited before being processed for product formation.
Claim 27
Dependent Claim 45 words
The method in accordance with claim 7 wherein there are derived by mixing the phase keyed oscillation with two mutually orthogonal auxiliary oscillations two further signals from which a control signal controlling the frequency of the auxiliary oscillations is obtained by limiting and product formation.
Claim 28
Dependent Claim 24 words
The method in accordance with claim 22 wherein the auxiliary oscillations mixed with the phase keyed high frequency oscillation are additionally wobbled in phase.
Claim 29
Dependent Claim 32 words
The method in accordance with claim 22 wherein at least selected ones of the amplitude limited signals are varied before being processed for product formation by the addition of variable additional signals.
Claim 30
Dependent Claim 16 words
The method in accordance with claim 24 wherein the variable additional signal comprises a noise signal.
Claim 31
Dependent Claim 17 words
The method in accordance with claim 21 wherein the variable additional signal comprises a periodic squarewave signal.
Claim 32
Dependent Claim 19 words
The method in accordance with claim 20 wherein the variable additional signal comprises a periodic and symmetrical sawtooth signal.
Claim 33
Dependent Claim 27 words
The method in accordance with claim 7 wherein the control signal is smoothed by a low-pass filter before being applied for frequency control of the auxiliary signals.
Claim 34
Dependent Claim 39 words
The method in accordance with claim 30 wherein a further control signal derived by rectification of the phase keyed high frequency oscillation is applied to produce an increase in the filter time-constant with diminishing amplitude of the high-frequency oscillation.
Claim 35
Dependent Claim 44 words
The method in accordance with claim 29 wherein there is derived by rectification of the control signal freed from direct-current components a further control signal which in response to diminishing amplitude of the control signal fluctuations increases the time constant of the subsequent smoothing.
Claim 36
Dependent Claim 21 words
The method in accordance with claim 7 wherein the phase evaluation is interrupted during the transitions between the individual keyed conditions.
Claim 37
Dependent Claim 25 words
The method in accordance with claim 7 wherein the control signal derived by product formation is interrupted during the transitions between the individual keyed conditions.

References Cited (Backward Citations)

US2481659A Cited
US2522371A Cited
US3638125A Cited
US3748590A Cited
US3789316A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1982-01-29 1982-07-31 1983-01-30 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1986-01-29 1986-07-31 1987-01-30 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1990-01-29 1990-07-31 1991-01-30 $7700.00 Window Closed / Lapsed

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