US4719642A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Error detection and concealment using predicted signal values
Assignee: Scientific Atlanta LLC
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Filing: 1985-02-27
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Granted: 1988-01-12
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Expires: 2005-02-27
Abstract
Abstract The system transmits blocks of N signal values preceded by block code words which are used at the receiver to detect errors. In the transmitter, the digital value of the intelligence signal being transmitted is sent to a predictor, a comparator, and an N-word delay line. The predictor estimates the next signal value, which is suitably delayed so that the current value and its estimate may be compared. The comparator subtracts each estimated value from the corresponding actual value, temporarily storing the difference, called a "delta value," while the entire block of N words is processed. A "Maximum Delta Encoder" encodes (with appropriate error correction) the absolute value of the maximum delta value for all N words. The resulting block code word is multiplexed into the data channel ahead of the group of N words to which it corresponds. An "N Sample Delay" is used to delay the N words so that the block code word will precede it. In the receiver, the block code word is demultiplexed and error corrected to recover the absolute value of the maximum delta value for the group of N words which follow. As each of the N words is received, it is subtracted from a predicted value generated by a predictor circuit identical to the one found in the transmitter. If the difference is greater than the maximum delta value for that block, the received signal value represents an error. The error is then concealed by replacing it with the predicted value itself. If the difference is less than or equal to the maximum delta value, the received signal is accepted as correct.
Inventors
- 👤 Keith Lucas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 21:20
CPC Classifications
H; H03; H03M; H03M13/00; G; G11; G11B; G11B20/00; G11B20/10; G11B20/18; G11B20/1876
Claims Analysis
Total Claims: 27
Claim 1
Independent Claim
118 words
A method of enabling the detection of errors introduced in an informal signal during transmission of the informal signal through a communication channel to a receiver, said method comprising the steps of: predicting from the untransmitted information signal a plurality of actual values of the information signal and generating therefrom a plurality of predicted values; determining the difference between each of the plurality of actual values and the corresponding predicted value; developing an error detection signal based on a comparison of the determined differences between each of the plurality of actual values and the corresponding predicted value; transmitting the plurality of actual values through the channel to the receiver; and transmitting the error detection signal to the receiver.
Claim 2
Independent Claim
118 words
A method of enabling the detection of errors introduced in an informal signal during transmission of the informal signal through a communication channel to a receiver, said method comprising the steps of: predicting from the untransmitted information signal a plurality of actual values of the information signal and generating therefrom a plurality of predicted values; determining the difference between each of the plurality of actual values and the corresponding predicted value; developing an error detection signal based on a comparison of the determined differences between each of the plurality of actual values and the corresponding predicted value; transmitting the plurality of actual values through the channel to the receiver; and transmitting the error detection signal to the receiver.
Claim 3
Dependent Claim
13 words
The method of claim 1 wherein the information signal is a correlated signal.
Claim 4
Independent Claim
176 words
A method of detecting errors introduced into an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: predicting from the untransmitted information signal a plurality of actual values of the information signal; determining the difference between each of the plurality of actual values and the corresponding prediction; developing an error detection signal from the determined differences between each of the plurality of actual values and the corresponding prediction; transmitting the plurality of actual values through the channel to the receiver; transmitting the error detection signal to the receiver; receiving the transmitted plurality of actual values and the transmitted error detection signal at the receiver; predicting from the received actual values each of the plurality of actual values of the received information signal; determining the difference between each of the plurality of received actual values and the corresponding prediction; and comparing the received error detection signal with determined differences between each of the plurality of received actual values in the corresponding prediction to detect errors.
Claim 5
Independent Claim
176 words
A method of detecting errors introduced into an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: predicting from the untransmitted information signal a plurality of actual values of the information signal; determining the difference between each of the plurality of actual values and the corresponding prediction; developing an error detection signal from the determined differences between each of the plurality of actual values and the corresponding prediction; transmitting the plurality of actual values through the channel to the receiver; transmitting the error detection signal to the receiver; receiving the transmitted plurality of actual values and the transmitted error detection signal at the receiver; predicting from the received actual values each of the plurality of actual values of the received information signal; determining the difference between each of the plurality of received actual values and the corresponding prediction; and comparing the received error detection signal with determined differences between each of the plurality of received actual values in the corresponding prediction to detect errors.
Claim 6
Dependent Claim
13 words
The method of claim 3 wherein the information signal is a correlated signal.
Claim 7
Independent Claim
99 words
A method of enabling the detection of errors introduced in an information signal during transmission of the information signal through a communication channel to a receiver, said method comprising the steps of; periodically sampling the information signal; calculating from the untransmitted samples a predicted value corresponding to each sample; determining the difference between each sample and the corresponding predicted value; developing an error detection signal based on a comparison of the determined differences between each sample and the corresponding predicted value; transmitting the samples through the channel to the receiver; and transmitting the error detection signal to the receiver.
Claim 8
Independent Claim
99 words
A method of enabling the detection of errors introduced in an information signal during transmission of the information signal through a communication channel to a receiver, said method comprising the steps of; periodically sampling the information signal; calculating from the untransmitted samples a predicted value corresponding to each sample; determining the difference between each sample and the corresponding predicted value; developing an error detection signal based on a comparison of the determined differences between each sample and the corresponding predicted value; transmitting the samples through the channel to the receiver; and transmitting the error detection signal to the receiver.
Claim 9
Dependent Claim
54 words
The method of claim 5 wherein the information signal has known statistical properties and said step of calculating from the untransmitted samples a predicted value corresponding to each sample comprises calculating the predicted value based solely on the value of one or more previous untransmitted samples and the statistical properties of the information signal.
Claim 10
Independent Claim
153 words
A method of detecting errors introduced in an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: periodically sampling the information signal; calculating from the untransmitted samples a predicted value corresponding to each sample; determining the difference between each sample and the corresponding predicted value; developing an error detection signal from the determined differences between each sample and the corresponding predicted value; transmitting the samples through the channel to the receiver; transmitting the error detection signal to the receiver; receiving the transmitted samples and the transmitted error detection signal at the receiver; calculating from the received samples a predicted value corresponding to each of the samples; determining the difference between each received sample and the corresponding predicted value; and comparing the received error detection signal with the determined differences between each received sample and the corresponding predicted value to detect errors.
Claim 11
Independent Claim
153 words
A method of detecting errors introduced in an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: periodically sampling the information signal; calculating from the untransmitted samples a predicted value corresponding to each sample; determining the difference between each sample and the corresponding predicted value; developing an error detection signal from the determined differences between each sample and the corresponding predicted value; transmitting the samples through the channel to the receiver; transmitting the error detection signal to the receiver; receiving the transmitted samples and the transmitted error detection signal at the receiver; calculating from the received samples a predicted value corresponding to each of the samples; determining the difference between each received sample and the corresponding predicted value; and comparing the received error detection signal with the determined differences between each received sample and the corresponding predicted value to detect errors.
Claim 12
Dependent Claim
86 words
The method of claim 7 wherein: the information signal has known statistical properties; said step of calculating from the untransmitted samples a predicted value comprises calculating the predicted value based solely on the value of one or more previous untransmitted samples and the statistical properties of the information signal; and said step of calculating from the received samples a predicted value comprises calculating the predicted value based solely on the value of one or more previous received samples and the statistical properties of the information signal.
Claim 13
Independent Claim
123 words
A method of detecting and concealing errors introduced into an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: receiving a plurality of actual values of the information signal; predicting from the received actual values each of the plurality of actual values of the received information signal; determining the difference between each of the plurality of received actual values and the corresponding prediction; receiving a maximum difference value; comparing the received maximum difference value with the determined differences between each of the plurality of received actual values and the corresponding prediciton in order to detect errors; and substituting, for any received actual value detected to be in error, the corresponding prediction.
Claim 14
Independent Claim
123 words
A method of detecting and concealing errors introduced into an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: receiving a plurality of actual values of the information signal; predicting from the received actual values each of the plurality of actual values of the received information signal; determining the difference between each of the plurality of received actual values and the corresponding prediction; receiving a maximum difference value; comparing the received maximum difference value with the determined differences between each of the plurality of received actual values and the corresponding prediciton in order to detect errors; and substituting, for any received actual value detected to be in error, the corresponding prediction.
Claim 15
Dependent Claim
91 words
The method of claim 9 further comprising the inital steps of: predicting from the untransmitted information signal a plurality of actual values of the information signal; determining the difference between each of the plurality of actual values of the untransmitted information signal and the corresponding prediction; evaluating the maximum value of the determined differences between each of the plurality of actual values of the untransmitted information signal and the corresponding prediction over a predetermined period of time; and transmitting the evaluated maximum value to the receiver as the maximum difference value.
Claim 16
Independent Claim
110 words
A method of detecting and concealing errors introduced into an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: receiving a plurality of samples of the information signal; calculating from the received samples a predicted value corresponding to each of the samples; determining the difference between each received sample and the corresponding predicted value; receiving a maximum difference value; comparing the received maximum difference value with the determined differences between each received sample and the corresponding predicted value in order to detect errors; and substituting, for any received sample detected to be in error, the corresponding predicted value.
Claim 17
Independent Claim
110 words
A method of detecting and concealing errors introduced into an information signal during passage of the information signal through a communication channel to a receiver, said method comprising the steps of: receiving a plurality of samples of the information signal; calculating from the received samples a predicted value corresponding to each of the samples; determining the difference between each received sample and the corresponding predicted value; receiving a maximum difference value; comparing the received maximum difference value with the determined differences between each received sample and the corresponding predicted value in order to detect errors; and substituting, for any received sample detected to be in error, the corresponding predicted value.
Claim 18
Dependent Claim
89 words
The method of claim 11 further comprising the initial steps of: calculating from the untransmitted information signal a predicted value corresponding to each of a plurality of samples of the information signal; determining the difference between each sample of the untransmitted information signal and the corresponding predicted value; evaluating the maximum value of the determined differences between each sample of the untransmitted information signal and the corresponding predicted value for a predtermined number of samples; and transmitting the evaluated maximum value to the receiver as the maximum difference value.
Claim 19
Independent Claim
91 words
A method of detecting errors in actual signal values comprising the steps of: periodically sampling a received signal for producing a plurality of actual signal values; predicting an actual signal value based on the plurality of actual signal values; comparing the predicted signal value to the actual signal value, producing a delta value; determining a maximum delta value for a group of N consecutive samples, where N is a positive integer; and detecting an error if and only if the produced delta value is greater than the predetermined maximum delta value.
Claim 20
Independent Claim
91 words
A method of detecting errors in actual signal values comprising the steps of: periodically sampling a received signal for producing a plurality of actual signal values; predicting an actual signal value based on the plurality of actual signal values; comparing the predicted signal value to the actual signal value, producing a delta value; determining a maximum delta value for a group of N consecutive samples, where N is a positive integer; and detecting an error if and only if the produced delta value is greater than the predetermined maximum delta value.
Claim 21
Dependent Claim
11 words
The method of claim 13 where N is greater than one.
Claim 22
Independent Claim
93 words
A method of detecting and concealing errors in actual signal values comprising the steps of: predicting an actual signal value based on at least one previous actual signal value; comparing the predicted signal value to the corresponding actual signal value, producing a delta value; comparing the delta value to a predetermined maximum delta value; detecting an error if and only if the delta value is greater than the predetermined maximum delta value; and if an error is detected, concealing the error by replacing the actual signal value with the corresponding predicted signal value.
Claim 23
Independent Claim
93 words
A method of detecting and concealing errors in actual signal values comprising the steps of: predicting an actual signal value based on at least one previous actual signal value; comparing the predicted signal value to the corresponding actual signal value, producing a delta value; comparing the delta value to a predetermined maximum delta value; detecting an error if and only if the delta value is greater than the predetermined maximum delta value; and if an error is detected, concealing the error by replacing the actual signal value with the corresponding predicted signal value.
Claim 24
Dependent Claim
35 words
The method of claim 15 wherein the actual signal values are represented by periodic samples, the predetermined maximum delta value being determined for a group of N consecutive periods, where N is a positive integer.
Claim 25
Dependent Claim
11 words
The method of claim 16 where N is greater than one.
Claim 26
Independent Claim
96 words
A method of generating error detection information from periodically sampled actual signal values, said method comprising the steps of: predicting an actual signal value based on at least one previous actual signal value; comparing the predicted signal value to the corresponding actual signal value, producing a delta value; and repeating said steps of predicting and comparing for a total of N actual signal values, where N is a positive integer, while: delaying the actual signal value a period of time corresponding to N sampling rates, and storing the largest delta value as the error detection information.
Claim 27
Independent Claim
96 words
A method of generating error detection information from periodically sampled actual signal values, said method comprising the steps of: predicting an actual signal value based on at least one previous actual signal value; comparing the predicted signal value to the corresponding actual signal value, producing a delta value; and repeating said steps of predicting and comparing for a total of N actual signal values, where N is a positive integer, while: delaying the actual signal value a period of time corresponding to N sampling rates, and storing the largest delta value as the error detection information.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1991-01-11 | 1991-07-13 | 1992-01-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1995-01-11 | 1995-07-13 | 1996-01-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1999-01-11 | 1999-07-13 | 2000-01-12 | $7700.00 | Window Closed / Lapsed |