US3593275A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method and apparatus for the recognition of errors at the receiver in a data transmission system
Assignee: Siemens AG
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Filing: 1968-07-09
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Granted: 1971-07-13
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Expires: 1988-07-09
Abstract
Abstract An error recognition process for a system in which data is transmitted in a one out of m different modulation characteristics (e.g. frequencies) code and wherein errors at the transmitter, or in the transmission system can cause a plurality of modulation characteristics to exist simultaneously at the receiver. The method of the invention takes advantage of the fact that modulation products outside of the assigned frequency band result when two different modulation characteristics are combined in a nonlinear device. Frequencies outside of the assigned band are detected to furnish an error voltage which blocks the decoded output at the receiver to prevent errors.
Inventors
- 👤 Gerhard Pumpe
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 07:25
CPC Classifications
H; H03; H03M; H03M13/00; H03M13/47; H03M13/51
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
150 words
Apparatus for detecting errors in received signals which are transmitted in binary coded form wherein each coded element of said signals comprises a single frequency selected from a predetermined group of frequencies comprising: filter means for sensing in said received signals modulation products occurring upon the appearance of more than one frequency of said predetermined group, said modulation products lying outside of the frequency band of said coded signals, but within a predetermined band width, evaluation circuit means for evaluating the amplitude of the signal resulting from the said sensed modulation products and for producing an error signal when said signal resulting from said modulation products exceeds an amplitude of a predetermined value, and output means for said received signals and having said error signal coupled thereto, said output means being adapted to be blocked to prevent the passage of said received signals thereto when said error signal is present.
Claim 2
Dependent Claim
150 words
Apparatus for detecting errors in received signals which are transmitted in binary coded form wherein each coded element of said signals comprises a single frequency selected from a predetermined group of frequencies comprising: filter means for sensing in said received signals modulation products occurring upon the appearance of more than one frequency of said predetermined group, said modulation products lying outside of the frequency band of said coded signals, but within a predetermined band width, evaluation circuit means for evaluating the amplitude of the signal resulting from the said sensed modulation products and for producing an error signal when said signal resulting from said modulation products exceeds an amplitude of a predetermined value, and output means for said received signals and having said error signal coupled thereto, said output means being adapted to be blocked to prevent the passage of said received signals thereto when said error signal is present.
Claim 3
Dependent Claim
25 words
The apparatus defined in claim 1 wherein said evaluation circuit is adapted to evaluate the disturbance modulation products in a plurality of groups of frequencies.
Claim 4
Independent Claim
131 words
A method for detecting errors in received data signals by using one of a predetermined group of frequencies for each code element of the signal, and wherein the disturbances caused by the actuation of more than one of said frequencies at a time are detected as errors, and comprising the steps of: filtering the received signals so that a signal corresponding to the modulation products of more than one of said frequencies lying outside of the transmission band width of said data signals, but within a predetermined band width, is filtered out, evaluating said filter signal and producing an error signal when the amplitude of said filtered signal exceeds a predetermined value, and blocking the passage of The date signals through a receiver means therefore, when an error signal is present.
Claim 5
Independent Claim
131 words
A method for detecting errors in received data signals by using one of a predetermined group of frequencies for each code element of the signal, and wherein the disturbances caused by the actuation of more than one of said frequencies at a time are detected as errors, and comprising the steps of: filtering the received signals so that a signal corresponding to the modulation products of more than one of said frequencies lying outside of the transmission band width of said data signals, but within a predetermined band width, is filtered out, evaluating said filter signal and producing an error signal when the amplitude of said filtered signal exceeds a predetermined value, and blocking the passage of The date signals through a receiver means therefore, when an error signal is present.
Claim 6
Dependent Claim
21 words
The method of claim 1, in which said filtered signal is developed only from frequencies lying above said assigned frequency band.
Claim 7
Dependent Claim
21 words
The method of claim 1, in which said filtered signal is developed only from frequencies lying below said assigned frequency band.
Claim 8
Dependent Claim
28 words
The method of claim 1, in which filtered signal is developed by filtering out modulation products, to the exclusion or harmonics of frequencies within said assigned frequency band.
Claim 9
Dependent Claim
98 words
The method of claim 1, in which signals within said assigned frequency band are limited and then discriminated as to said modulation characteristics to decode the received signal to furnish an output signal (A1- A4) representative of the data, the limited signals being also filtered (F1) to develop said filtered signal only from the modulation products lying outside of said assigned frequency band, the said filtered signal then being evaluated as to amplitude (AB2) to provide an error signal (S) when the voltage exceeds a predetermined amplitude, and said error signal when present blocks any said output signal.
References Cited (Backward Citations)
US3131264A
Cited
US3104356A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1974-07-12 | 1975-01-11 | 1975-07-13 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1978-07-12 | 1979-01-11 | 1979-07-13 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-07-12 | 1983-01-11 | 1983-07-13 | $7700.00 | Window Closed / Lapsed |