US3656152A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Improved a-d/d-a converter system
Assignee: Raytheon Co
•
Filing: 1970-02-16
•
Granted: 1972-04-11
•
Expires: 1990-02-16
Abstract
Abstract A system for transmitting digital representations of analog signals which increases resolution without a corresponding increase in the number of bits in the digital data which is transmitted. In one embodiment, the analog input signal is applied to a level change circuit and summed with a square wave having peak-to-peak voltage equal to one-half the magnitude of the value of the least significant bit of the digital representation. The square wave pattern output of the level change circuit is applied to an analog-to-digital converter and the digital output is transmitted to a digital-to-analog converter. The output of the digital-to-analog converter is filtered to provide the analog output signal. During the time that the square wave pattern crosses an analog-to-digital converter threshold value, the resultant digital-to-analog output is a square wave with an average value between the normal discrete analog output levels. This results in twice as many levels at the analog output which is equivalent to the addition of one bit of resolution.
Inventors
- 👤 James L Gundersen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 22:23
CPC Classifications
H; H04; H04B; H04B14/00; H04B14/02; H04B14/04; H04B14/046; H03; H03M; H03M1/00; H03M1/06; H03M1/08
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
126 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: means for adding a square wave signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the digital representation to said analog input signal to obtain a resultant analog signal, means for converting the resultant analog signal to a digital representation, means for converting the digital representation to an analog signal containing a square wave component, and means for averaging said square wave component of the analog signal to provide said analog output signal.
Claim 2
Independent Claim
126 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: means for adding a square wave signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the digital representation to said analog input signal to obtain a resultant analog signal, means for converting the resultant analog signal to a digital representation, means for converting the digital representation to an analog signal containing a square wave component, and means for averaging said square wave component of the analog signal to provide said analog output signal.
Claim 3
Independent Claim
200 words
A system for converting an analog input signal to a digital representation of n bits where n in an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, circuit means for adding a square wave signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter means to said analog input signal to obtain a resultant signal, means for coupling the resultant signal of said circuit means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means for providing an analog signal containing a square wave component, and averaging means coupled to receive the analog signal of said digital-to-analog converter means for averaging said square wave component of the received signal to provide said analog output signal.
Claim 4
Independent Claim
200 words
A system for converting an analog input signal to a digital representation of n bits where n in an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, circuit means for adding a square wave signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter means to said analog input signal to obtain a resultant signal, means for coupling the resultant signal of said circuit means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means for providing an analog signal containing a square wave component, and averaging means coupled to receive the analog signal of said digital-to-analog converter means for averaging said square wave component of the received signal to provide said analog output signal.
Claim 5
Dependent Claim
19 words
The system claimed in claim 2 wherein said circuit means includes: a free running multivibrator, and a summing Amplifier.
Claim 6
Dependent Claim
15 words
The system claimed in claim 2 wherein said averaging means includes a low pass filter.
Claim 7
Independent Claim
227 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, signal generator means for generating a square wave signal output having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter means, signal combining means coupled to receive said analog input signal and the square wave signal output of said signal generator means for providing an output signal which is the sum of the received signals, means for coupling the output signal of said signal combining means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means for providing an analog signal containing a square wave component, and averaging means coupled to receive the analog signal of said digital-to-analog converter means for averaging said square wave component of the received signal to provide said analog output signal.
Claim 8
Independent Claim
227 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, signal generator means for generating a square wave signal output having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter means, signal combining means coupled to receive said analog input signal and the square wave signal output of said signal generator means for providing an output signal which is the sum of the received signals, means for coupling the output signal of said signal combining means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means for providing an analog signal containing a square wave component, and averaging means coupled to receive the analog signal of said digital-to-analog converter means for averaging said square wave component of the received signal to provide said analog output signal.
Claim 9
Dependent Claim
33 words
The system claimed in claim 5 wherein: said signal generator means includes a free running multivibrator, said signal combining means includes a summing amplifier, and said averaging means includes a low pass filter.
Claim 10
Independent Claim
295 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, control means for providing a control signal when the digital representation of said analog-to-digital converter means is available at its output, circuit means having two stable states coupled to receive the control signal of said control means for providing an output signal which changes state in response to the received signal, signal conditioning means coupled to receive the output signal of said circuit means for providing an adjusted peak-to-peak voltage of said circuit means output signal equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter means, signal combining means coupled to receive said analog input signal and the adjusted peak-to-peak voltage of said signal conditioning means for providing an output signal which is the sum of the received signals, means for coupling the output signal of said signal combining means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means and the control signal of said control means for providing an analog signal containing a square wave component, and averaging means coupled to receive the analog signal of said digital-to-analog converter for averaging said square wave component of the received signal to provide said analog output signal.
Claim 11
Independent Claim
295 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n 1, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, control means for providing a control signal when the digital representation of said analog-to-digital converter means is available at its output, circuit means having two stable states coupled to receive the control signal of said control means for providing an output signal which changes state in response to the received signal, signal conditioning means coupled to receive the output signal of said circuit means for providing an adjusted peak-to-peak voltage of said circuit means output signal equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter means, signal combining means coupled to receive said analog input signal and the adjusted peak-to-peak voltage of said signal conditioning means for providing an output signal which is the sum of the received signals, means for coupling the output signal of said signal combining means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means and the control signal of said control means for providing an analog signal containing a square wave component, and averaging means coupled to receive the analog signal of said digital-to-analog converter for averaging said square wave component of the received signal to provide said analog output signal.
Claim 12
Dependent Claim
24 words
The system claimed in claim 7 wherein: said signal combining means includes a summing amplifier, and said averaging means incLudes a low pass filter.
Claim 13
Independent Claim
365 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n m where m is an integer, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, control means for providing a control signal when the digital representation of said analog-to-digital converter means is available at its output, binary counter means having m stages coupled to receive the control signal of said control means for counting one count each time a control signal is received and for providing an output signal from each stage indicative of the state of that stage, signal conditioning means coupled to receive the output signals from each stage of said binary counter means for providing an adjusted output signal for the first stage of said binary counter means, the adjusted output signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter, and for providing an adjusted output signal for each succeeding stage of said binary counter means, the adjusted output signal for each succeeding stage having a peak-to-peak voltage equal to one-half the adjusted output signal of the preceding stage, signal combining means coupled to receive said analog input signal and the adjusted output signals of said signal conditioning means for providing an output signal which is the sum of the received signals, means for coupling the output signal of said signal combining means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means and the control signal of said control means for providing an analog signal containing a square wave component, and means coupled to receive the analog signal of said digital-to-analog converter for averaging said square wave component of the received signal to provide said analog output signal.
Claim 14
Independent Claim
365 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n m where m is an integer, said system comprising: analog-to-digital converter means for providing an output which is a digital representation of an analog signal applied to its input, said analog-to-digital converter means having threshold levels equal to the equivalent analog voltage of the least significant bit of the output signal, control means for providing a control signal when the digital representation of said analog-to-digital converter means is available at its output, binary counter means having m stages coupled to receive the control signal of said control means for counting one count each time a control signal is received and for providing an output signal from each stage indicative of the state of that stage, signal conditioning means coupled to receive the output signals from each stage of said binary counter means for providing an adjusted output signal for the first stage of said binary counter means, the adjusted output signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the output signal of said analog-to-digital converter, and for providing an adjusted output signal for each succeeding stage of said binary counter means, the adjusted output signal for each succeeding stage having a peak-to-peak voltage equal to one-half the adjusted output signal of the preceding stage, signal combining means coupled to receive said analog input signal and the adjusted output signals of said signal conditioning means for providing an output signal which is the sum of the received signals, means for coupling the output signal of said signal combining means to the input of said analog-to-digital converter means, digital-to-analog converter means coupled to receive the output of said analog-to-digital converter means and the control signal of said control means for providing an analog signal containing a square wave component, and means coupled to receive the analog signal of said digital-to-analog converter for averaging said square wave component of the received signal to provide said analog output signal.
Claim 15
Dependent Claim
24 words
The system claimed in claim 9 wherein: said signal combining means includes a summing amplifier, and said averaging means includes a low pass filter.
Claim 16
Independent Claim
236 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n m where m is an integer, said system comprising: counter means having m stages for providing an output signal from each stage indicative of the state of that stage, signal conditioning means coupled to receive the output signals from each stage of said counter means for providing an adjusted output signal for the first stage of said counter means, the adjusted output signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the digital representation, and for providing an adjusted output signal for each succeeding stage of said counter means, the adjusted output signal for each succeeding stage having a peak-to-peak voltage equal to one-half the adjusted output signal of the preceding stage, means for combining said analog input signal and the adjusted output signals of said signal conditioning means to obtain a resultant analog signal which is the sum of the received signals, means for converting the resultant analog signal to a digital representation, means for converting the digital representation to an analog signal containing a square wave component, and means for aveRaging said square wave component of the analog signal to provide said analog output signal.
Claim 17
Independent Claim
236 words
A system for converting an analog input signal to a digital representation of n bits where n is an integer, transmitting the digital representation and converting it to an analog output signal, said system having a resolution of 1/2 n m where m is an integer, said system comprising: counter means having m stages for providing an output signal from each stage indicative of the state of that stage, signal conditioning means coupled to receive the output signals from each stage of said counter means for providing an adjusted output signal for the first stage of said counter means, the adjusted output signal having a peak-to-peak voltage equal to one-half the equivalent analog voltage of the least significant bit of the digital representation, and for providing an adjusted output signal for each succeeding stage of said counter means, the adjusted output signal for each succeeding stage having a peak-to-peak voltage equal to one-half the adjusted output signal of the preceding stage, means for combining said analog input signal and the adjusted output signals of said signal conditioning means to obtain a resultant analog signal which is the sum of the received signals, means for converting the resultant analog signal to a digital representation, means for converting the digital representation to an analog signal containing a square wave component, and means for aveRaging said square wave component of the analog signal to provide said analog output signal.
References Cited (Backward Citations)
US2974315A
Cited
US2909676A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-04-11 | 1975-10-11 | 1976-04-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-04-11 | 1979-10-11 | 1980-04-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-04-11 | 1983-10-11 | 1984-04-11 | $7700.00 | Window Closed / Lapsed |