Patent US4994768A successfully refreshed from Google Patents.
US4994768A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Frequency synthesizer with FM modulation
Assignee: Quarterhill Inc
•
Filing: 1990-03-26
•
Granted: 1991-02-19
•
Expires: 2010-03-26
Abstract
Abstract A frequency synthesizer (10) for providing a modulated output signal (fo) includes a reference frequency signal (fr) and a voltage controlled oscillator (14). For dividing the frequency of the output signal from the voltage controlled oscillator (14) by a divisor, a programmable divider (16) is coupled to the output of the voltage controlled oscillator (14). To produce a phase-locked loop in which the frequency of the output signal from the voltage controlled oscillator (14) is equal to the frequency of the reference frequency (fr) signal multiplied by the divisor, a phase detector (12 ) having a first input coupled to the reference frequency signal (fr), a second input coupled to the output of the programmable divider (16), and an output coupled to the input of the voltage controlled oscillator (14) is also provided. A first integrator (24) for integrating a modulating signal provides an integrated signal and a first control signal. Similarly, a second integrator (25) coupled to the first integrator (24) for integrating the integrated signal provides a second control signal. A differentiator ( 36, 42 and 48) coupled to the second integrator (25) differentiates the second control signal to provide a third control signal. Finally, a processor (41 and 43) coupled to the first integrator (24), the second integrator (25) and the differentiator (36, 42 and 48) processes the first, second, and third control signals and a divider modulus code (M). The processor (41 and 43) coupled to the programmable divider modifies the divider modulus code (M) in response to the modulating signal (9) to provide the divisor, whereby the frequency of the output signal from the voltage controlled oscillator (14) is modulated by the modulating signal (9).
Inventors
- 👤 Wayne P. Shepherd
- 👤 Darrell E. Davis
- 👤 Frederick L. Martin
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 16:42
CPC Classifications
H; H03; H03C; H03C3/00; H03C3/02; H03C3/09; H03C3/0908; H03C3/0966; H03C3/0916; H03C3/0925; H03C3/0933; H03C3/0941; H03C3/0958
Claims Analysis
Total Claims: 26
Claim 1
Independent Claim
255 words
A frequency synthesizer for providing a modulated output signal, comprising: means for producing a reference frequency signal; a voltage controlled oscillator; programmable dividing means coupled to the output of the voltage controlled oscillator for dividing the frequency of the output signal from the voltage controlled oscillator by a divisor; phase detector means having a first input coupled to said means for producing a reference frequency signal, a second input coupled to the output of said programmable dividing means, and an output coupled to the input of the voltage controlled oscillator to produce a phase-locked loop in which the frequency of the output signal from the voltage controlled oscillator is equal to the frequency of the reference frequency signal multiplied by said divisor; first integrating means for integrating a modulating signal to provide an integrated signal and a first control signal; second integrating means coupled to said first integrating means for integrating said integrated signal to provide a second control signal; differentiating means coupled to said second integrating means for differentiating said second control signal to provide a third control signal; and processing means coupled to said first integrating means, said second integrating means, and said differentiating means for processing said first, second, and third control signals and a divider modulus code, said processing means modifying said divider modulus code in response to said modulating signal and being coupled to said programmable dividing means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulating signal.
Claim 2
Dependent Claim
255 words
A frequency synthesizer for providing a modulated output signal, comprising: means for producing a reference frequency signal; a voltage controlled oscillator; programmable dividing means coupled to the output of the voltage controlled oscillator for dividing the frequency of the output signal from the voltage controlled oscillator by a divisor; phase detector means having a first input coupled to said means for producing a reference frequency signal, a second input coupled to the output of said programmable dividing means, and an output coupled to the input of the voltage controlled oscillator to produce a phase-locked loop in which the frequency of the output signal from the voltage controlled oscillator is equal to the frequency of the reference frequency signal multiplied by said divisor; first integrating means for integrating a modulating signal to provide an integrated signal and a first control signal; second integrating means coupled to said first integrating means for integrating said integrated signal to provide a second control signal; differentiating means coupled to said second integrating means for differentiating said second control signal to provide a third control signal; and processing means coupled to said first integrating means, said second integrating means, and said differentiating means for processing said first, second, and third control signals and a divider modulus code, said processing means modifying said divider modulus code in response to said modulating signal and being coupled to said programmable dividing means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulating signal.
Claim 3
Dependent Claim
71 words
The frequency synthesizer of claim 1 wherein said processing means comprises: encoder means having inputs for said first, second, and third control signals; adder means coupled to said encoder means and having an input for said divider modulus code; and analog-to-digital conversion means being coupled to said first integrating means for digitizing an input modulating signal, said processing means modifying said divider modulus code in response to said input modulating signal.
Claim 4
Dependent Claim
14 words
The frequency synthesizer of claim 1 wherein said means for integrating comprise summing means.
Claim 5
Dependent Claim
14 words
The frequency synthesizer of claim 1 wherein said means for integrating comprise summing means.
Claim 6
Dependent Claim
24 words
The frequency synthesizer of claim 1 wherein said first, second, and third control signal each consists of a first output and a second output.
Claim 7
Dependent Claim
75 words
The frequency synthesizer of claim 1 wherein said first integrating means comprises: a first carry output and a second carry output to provide said first control signal for varying said divider modulus code, said first integrating means being operable to cumulatively add said modulating signal to a content therein to provide a first cumulative sum to generate said first control signal; and a third output for providing said integrated signal to said second integrating means.
Claim 8
Dependent Claim
74 words
The frequency synthesizer of claim 6 wherein said second integrating means comprises: an input connected to said third output of said second integrating means; and a first carry output and a second carry output to provide said second control signal for varying said divider modulus code, said second integrating means being operable to cumulatively add said integrated signal to a content therein to provide a second cumulative sum to generate said second control signal.
Claim 9
Dependent Claim
68 words
The frequency synthesizer of claim 7 wherein said differentiating means comprises a first delaying and inverting means coupled to said first carry output of said second control signal to provide a first inverted output of said third control signal and a second delaying and inverting means coupled to said second carry output of said second control signal to provide a second inverted output of said third control signal.
Claim 10
Dependent Claim
17 words
The frequency synthesizer of claim 8 wherein said first delaying and inverting means comprises a first flip-flop.
Claim 11
Dependent Claim
45 words
The frequency synthesizer of claim 9 wherein said second delaying and inverting means comprises an inverter coupled to said second carry output of said second control signal and being coupled to a second flip-flop to provide said second inverted output of said third control signal.
Claim 12
Dependent Claim
33 words
The frequency synthesizer of claim 6 wherein said first carry output of said control signal increases said divider modulus code when said first cumulative sum reaches at least a predetermined positive threshold value.
Claim 13
Dependent Claim
34 words
The frequency synthesizer of claim 6 wherein said second carry output of said first control signal decreases said divider modulus code when said first cumulative sum reaches at least a predetermined negative threshold value.
Claim 14
Dependent Claim
47 words
The frequency synthesizer of claim 8 wherein said first carry output of said second control signal and said first inverted output of said third control signal increase and subsequently decrease said divider modulus code when said second cumulative sum reaches at least a predetermined positive threshold value.
Claim 15
Dependent Claim
32 words
The frequency synthesizer of claim 8 wherein said first carry output of said second control signal is coupled to said first delaying and inverting means to subsequently decrease said divider modulus code.
Claim 16
Dependent Claim
47 words
The frequency synthesizer of claim 8 wherein said second carry output of said second control signal and said second inverted output of said third control signal decrease and subsequently increase said divider modulus code when said second cumulative sum reaches at least a predetermined negative threshold value.
Claim 17
Dependent Claim
32 words
The frequency synthesizer of claim 8 wherein said second carry output of said second control signal is coupled to said second delaying and inverting means to subsequently increase said divider modulus code.
Claim 18
Dependent Claim
25 words
The frequency synthesizer of claim 10 wherein said first and second integrating means, and said first and second flip-flops are clocked at said reference frequency.
Claim 19
Independent Claim
222 words
A method of modulating a synthesizer, comprising the steps of: producing a reference frequency signal; producing an output frequency signal from a voltage controlled oscillator; dividing the frequency of the output frequency signal by a divisor in a programmable dividing means; comparing said reference and divided output frequency signals in a phase detector means to produce a phase control signal; controlling said voltage controlled oscillator with said phase control signal so that said output frequency signal becomes equal to said reference frequency signal multiplied by said divisor; integrating a modulating signal in a first integrating means to provide an integrated signal and a first control signal; integrating said integrated signal from said first integrating means in a second integrating means to provide a second control signal; differentiating said second control signal from said second integrating means in a differentiating means to provide a third control signal; and processing said first, second, and third control signals and a divider modulus code in a processing means coupled to said first integrating means, said second integrating means and said differentiating means, said processing means modifying said divider modulus code in response to said modulating signal and being coupled to said programmable dividing means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulating signal.
Claim 20
Independent Claim
222 words
A method of modulating a synthesizer, comprising the steps of: producing a reference frequency signal; producing an output frequency signal from a voltage controlled oscillator; dividing the frequency of the output frequency signal by a divisor in a programmable dividing means; comparing said reference and divided output frequency signals in a phase detector means to produce a phase control signal; controlling said voltage controlled oscillator with said phase control signal so that said output frequency signal becomes equal to said reference frequency signal multiplied by said divisor; integrating a modulating signal in a first integrating means to provide an integrated signal and a first control signal; integrating said integrated signal from said first integrating means in a second integrating means to provide a second control signal; differentiating said second control signal from said second integrating means in a differentiating means to provide a third control signal; and processing said first, second, and third control signals and a divider modulus code in a processing means coupled to said first integrating means, said second integrating means and said differentiating means, said processing means modifying said divider modulus code in response to said modulating signal and being coupled to said programmable dividing means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulating signal.
Claim 21
Dependent Claim
232 words
A frequency synthesizer in a radio for providing a modulated output signal comprising: a voltage controlled oscillator; means for producing a frequency signal; programmable dividing means coupled to the output of the voltage controlled oscillator for dividing the frequency of the output signal from the voltage controlled oscillator by a divisor; phase detector means having a first input coupled to said means for producing a reference frequency signal, a second input coupled to the output of said programmable dividing means, and an output coupled to the input of the voltage controlled oscillator to produce a phase-locked loop in which the frequency of the output signal from the voltage controlled oscillator is equal to the frequency of the reference frequency signal multiplied by said divisor; signal converting means for receiving a modulation signal and for converting said modulation signal to digital signals; a cascaded plurality of integrating means for processing said digital signals to induce a plurality of phase adjustments into said phase-locked loop to track said modulation signal; divisor means coupled to said programmable dividing means and to said cascaded plurality of integrating means to modify a divider modulus code in response to said digital signals converted by said signal converting means and processed by said plurality of integrating means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulation signal.
Claim 22
Dependent Claim
232 words
A frequency synthesizer in a radio for providing a modulated output signal comprising: a voltage controlled oscillator; means for producing a frequency signal; programmable dividing means coupled to the output of the voltage controlled oscillator for dividing the frequency of the output signal from the voltage controlled oscillator by a divisor; phase detector means having a first input coupled to said means for producing a reference frequency signal, a second input coupled to the output of said programmable dividing means, and an output coupled to the input of the voltage controlled oscillator to produce a phase-locked loop in which the frequency of the output signal from the voltage controlled oscillator is equal to the frequency of the reference frequency signal multiplied by said divisor; signal converting means for receiving a modulation signal and for converting said modulation signal to digital signals; a cascaded plurality of integrating means for processing said digital signals to induce a plurality of phase adjustments into said phase-locked loop to track said modulation signal; divisor means coupled to said programmable dividing means and to said cascaded plurality of integrating means to modify a divider modulus code in response to said digital signals converted by said signal converting means and processed by said plurality of integrating means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulation signal.
Claim 23
Dependent Claim
192 words
A frequency synthesizer in a radio for providing a modulated output signal, comprising: phase-locked loop including means for producing a reference frequency signal, a phase detector, a voltage controlled oscillator, and programmable dividing means operatively connected to apply a divisor to the output of one of said voltage controlled oscillator and said means for producing a reference frequency signal; first integrating means for integrating a modulating signal to provide an integrated signal and a first control signal; second integrating means coupled to said first integrating means for integrating said integrated signal to provide a second control signal; differentiating means coupled to said second integrating means for differentiating said second control signal to provide a third control signal; and processing means coupled to said first integrating means, said second integrating means, and said differentiating means for processing said first, second, and third control signals and a divider modulus code, said processing means modifying said divider modulus code in response to said modulating signal and being coupled to said programmable dividing means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulating signal.
Claim 24
Dependent Claim
192 words
A frequency synthesizer in a radio for providing a modulated output signal, comprising: phase-locked loop including means for producing a reference frequency signal, a phase detector, a voltage controlled oscillator, and programmable dividing means operatively connected to apply a divisor to the output of one of said voltage controlled oscillator and said means for producing a reference frequency signal; first integrating means for integrating a modulating signal to provide an integrated signal and a first control signal; second integrating means coupled to said first integrating means for integrating said integrated signal to provide a second control signal; differentiating means coupled to said second integrating means for differentiating said second control signal to provide a third control signal; and processing means coupled to said first integrating means, said second integrating means, and said differentiating means for processing said first, second, and third control signals and a divider modulus code, said processing means modifying said divider modulus code in response to said modulating signal and being coupled to said programmable dividing means to provide said divisor, whereby the frequency of the output signal from the voltage controlled oscillator is modulated by said modulating signal.
Claim 25
Dependent Claim
48 words
The frequency synthesizer of claim 20 wherein said programmable dividing means is interposed between said means for producing a reference frequency signal and said phase detector for dividing the frequency of the reference frequency by said divisor, whereby the reference frequency signal is modulated by said modulating signal.
Claim 26
Dependent Claim
37 words
The frequency synthesizer of claim 20 wherein said programmable dividing means is interposed between said voltage controlled oscillator and said phase detector for dividing the frequency of the output signal from said voltage oscillator by said divisor.
References Cited (Backward Citations)
US4068199A
Cited
US4481489A
Cited
US4543542A
Cited
US4609881A
Cited
US4562414A
Cited
US4546331A
Cited
US4573026A
Cited
US4686488A
Cited
US4810977A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1994-02-18 | 1994-08-20 | 1995-02-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1998-02-18 | 1998-08-20 | 1999-02-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2002-02-18 | 2002-08-20 | 2003-02-19 | $7700.00 | Window Closed / Lapsed |