US3748602A
Expired / Lapsed
US
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Determination of equalizer setting in telecommunication system
Assignee: Italtel SpA
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Filing: 1972-06-08
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Granted: 1973-07-24
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Expires: 1992-06-08
Abstract
Abstract A wide-band equalizer for a telecommunication system includes a symmetrical corrector and an asymmetrical corrector, each encompassing the entire band, and a multiplicity of parallel corrective networks centered on the midfrequencies of respective sub-bands. A set of input registers, one for each sub-band, serve for the storage of error voltages representative of the deviations of the signal levels in the equalizer output from predetermined reference values as required under certain (e.g., seasonally variable) operating conditions. A correction simulator, switchable between a symmetrical and an asymmetrical position, generates a group of compensating voltages representing the effect of either of the two overall correctors upon the signal amplitudes in different zones of the band; a group of summing circuits differentially combine these compensating voltages with the stored error voltages relating to the same band zones to provide a composite voltage which is read on an indicator and is minimized by adjustment of the two overall correctors. Thereafter, modified error voltages representing the residual deviations are fed into the input registers and thence to a resistance matrix distributing them to a multiplicity of output terminals, assigned to the several midfrequencies, with a polarity and step-down ratio corresponding to the effects of each corrective network upon the respective midfrequencies; a selector switch provides a reading of the cumulative effect of all the corrective networks upon each midfrequency, with the aid of a further summing circuit, as a basis for an individual readjustment of these networks.
Inventors
- 👤 E Delfrate
- 👤 Nicolay G De
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 11:53
CPC Classifications
H; H04; H04B; H04B3/00; H04B3/02; H04B3/04; H04B3/14; H04B3/141
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
157 words
A method of determining the setting of an equalizer including a multiplicity of proportionally adjustable corrective networks with substantially Gaussian characteristics centered on the midfrequencies of respective sub-bands of a band of singal frequencies to be transmitted over a telecommunication path, comprising the steps of: storing, on a multiplicity of registers respectively assigned to said networks, a group of error voltages representative of deviations of signal levels at the corresponding midfrequencies in the equalizer output from predetermined reference values; multiplying the input voltage stored on each register with a plurality of proportionality factors each representative in sign and in magnitude of the effect of the corresponding network upon a respective midfrequency; additively combining, on a multiplicity of terminals respectively assigned to said midfrequencies, the error voltages from all said registers as multiplied by the corresponding proportionality factors; and measuring the additively combined voltage on each terminal as a basis for an individual readjustment of said corrective networks.
Claim 2
Independent Claim
157 words
A method of determining the setting of an equalizer including a multiplicity of proportionally adjustable corrective networks with substantially Gaussian characteristics centered on the midfrequencies of respective sub-bands of a band of singal frequencies to be transmitted over a telecommunication path, comprising the steps of: storing, on a multiplicity of registers respectively assigned to said networks, a group of error voltages representative of deviations of signal levels at the corresponding midfrequencies in the equalizer output from predetermined reference values; multiplying the input voltage stored on each register with a plurality of proportionality factors each representative in sign and in magnitude of the effect of the corresponding network upon a respective midfrequency; additively combining, on a multiplicity of terminals respectively assigned to said midfrequencies, the error voltages from all said registers as multiplied by the corresponding proportionality factors; and measuring the additively combined voltage on each terminal as a basis for an individual readjustment of said corrective networks.
Claim 3
Dependent Claim
98 words
A method as defined in claim 1 wherein the equalizer also includes a proportionally adjustable overall corrector exerting a significant effect upon the signal level of the entire band, comprising the further step of subtractively combining the error voltages stored on said registers with compensating voltages, each representative in sign and in magnitude of the effect of said overall corrector upon respective portions of the band, and measuring the resulting voltage as a basis for readjustment of said overall corrector and consequent modification of the stored error voltages prior to measuring the additively combined voltages on said terminals.
Claim 4
Dependent Claim
59 words
A method as defined in claim 2 wherein said overall corrector includes a plurality of separately adjustable sections with different characteristics, comprising the further step of modifying said compensating voltages in conformity with the characteristics of respective sections and indiviudally read-adjusting each section on the basis of said resulting voltage as obtained from a corresponding set of compensating voltages.
Claim 5
Dependent Claim
48 words
A method as defined in claim 2 wherein the number of said compensating voltages is a fraction of the number of said error voltages, the latter being additively combined in a number of subgroups equal to the number of compensating voltages upon being differentially combined with the latter.
Claim 6
Independent Claim
182 words
A system for determining the setting of an equalizer including a multiplicity of proportionally adjustable corrective networks with substantially Gaussian characteristics centered on the midfrequencies of respective sub-bands of a band of signal frequencies to be transmitted over a telecommunication path comprising: a multiplicity of input registers respectively assigned to said networks and connected to receive a group of error voltages representative of deviations of signal levels at corresponding midfrequencies in the equalizer output from predetermined reference values; circuitry connected to said registers for multiplying each stored error voltage with a plurality of proportionality factors each representative in sign and in magnitude of the effect of the corresponding network upon a respective midfrequency; a multiplicity of output terminals respectively assigned to said midfrequencies, said circuitry being connected to each of said output terminals for developing thereon an additive combination of the error voltages from all said registers as multiplied by the corresponding proportionality factors; and indicator means selectively connectable to said output terminals for determining the magnitudes of the combined voltages thereon as a basis for a readjustment of said corrective networks.
Claim 7
Independent Claim
182 words
A system for determining the setting of an equalizer including a multiplicity of proportionally adjustable corrective networks with substantially Gaussian characteristics centered on the midfrequencies of respective sub-bands of a band of signal frequencies to be transmitted over a telecommunication path comprising: a multiplicity of input registers respectively assigned to said networks and connected to receive a group of error voltages representative of deviations of signal levels at corresponding midfrequencies in the equalizer output from predetermined reference values; circuitry connected to said registers for multiplying each stored error voltage with a plurality of proportionality factors each representative in sign and in magnitude of the effect of the corresponding network upon a respective midfrequency; a multiplicity of output terminals respectively assigned to said midfrequencies, said circuitry being connected to each of said output terminals for developing thereon an additive combination of the error voltages from all said registers as multiplied by the corresponding proportionality factors; and indicator means selectively connectable to said output terminals for determining the magnitudes of the combined voltages thereon as a basis for a readjustment of said corrective networks.
Claim 8
Dependent Claim
14 words
A system as defined in claim 5 wherein said circuitry comprises a resistance matrix.
Claim 9
Dependent Claim
66 words
A system as defined in claim 6 wherein said circuitry further comprises a multiplicity of conductor pairs, one for each register, said output terminals being divided into two sets connected to respective conductors of each pair, said indicator means including an arithmetic stage with an additive input connectable to the terminals of one set and a subtractive input connectable to the terminals of the other set.
Claim 10
Dependent Claim
27 words
A system as defined in claim 7, further comprising a pair of ganged selector switches between said sets of terminals and said additive and subtractive inputs, respectively.
Claim 11
Dependent Claim
115 words
A system as defined in claim 5, wherein the equalizer also includes a proportionally adjustable overall corrector exerting a significant effect upon the signal level of the entire band, further comprising a proportionally adjustable simulator generating a plurality of compensating voltages each representative in sign and in magnitude of the effect of said overall corrector upon respective portions of the band, summing means connected to said registers and to said simulator for subtractively combining said error voltages with corresponding compensating voltages, and output means giving a reading of a resulting voltage from said summing means as a basis for reAdjustment of said overall corrector and consequent modification of the error voltages stored on said registers.
Claim 12
Dependent Claim
79 words
A system as defined in claim 9 wherein said simulator generates a number of compensating voltages equal to a fraction of the number of said registers, said summing means including a plurality of summing circuits, one for each compensating voltage, each connected to a respective subgroup of said registers for additively combining the error voltages stored thereon while subtracting therefrom a respective compensating voltage, said output means comprising an adder for the combined voltages of all said summing circuits.
Claim 13
Dependent Claim
42 words
A system as defined in claim 9 wherein said overall corrector includes a plurality of separately adjustable sections with different characteristics, said simulator being provided with switchover means for selectively modifying said corrective voltages in conformity with the characteristics of respective sections.
Claim 14
Dependent Claim
27 words
A system as defined in claim 11 wherein said sections include a first section with a substantially symmetrical characteristic and a second section with an asymmetrical characteristic.
References Cited (Backward Citations)
US2607851A
Cited
US3663898A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1976-07-23 | 1977-01-22 | 1977-07-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1980-07-23 | 1981-01-22 | 1981-07-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1984-07-23 | 1985-01-22 | 1985-07-24 | $7700.00 | Window Closed / Lapsed |