US5515398A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Modem line probing signal techniques
Assignee: HP Inc
•
Filing: 1994-03-15
•
Granted: 1996-05-07
•
Expires: 2014-03-15
Abstract
Abstract Techniques for generating a line probing signal. The probing signal is comprised of a plurality of different tones, where the tones have a predetermined phase relationship. The signal may be sent over a communication channel, such as a telephone line. By so using the line probing signal, the non-linearity of the electrical characteristics of the telephone line may be measured with increased accuracy.
Inventors
- 👤 Dale M. Walsh
- 👤 Vladimir Parizhsky
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 01:54
CPC Classifications
H; H04; H04L; H04L43/00; H04L43/50; H04B; H04B3/00; H04B3/02; H04B3/46; H04L1/00; H04L1/24; H04L1/242; H04L1/244; H04M; H04M3/00; H04M3/22; H04M3/26; H04M3/28; H04M3/30
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
227 words
A modem, associated with a computer, for generating a line probing signal over a communication channel for use by a receiving modem to determine the non-linearity of the electrical characteristics of said communication channel comprising, in combination: a first bus for communicating with said computer; a transmitter for generating a finite plurality of different tones, said tones having a predetermined relative phase relationship; and a second bus for delivering signals, including said tones, to said communication channel, said tones being divided into a first group having a first predetermined phase and a second group having a second predetermined phase, said first and second predetermined phases having a predetermined phase relationship, said predetermined phase relationship arranged to substantially minimize the peak to root mean square average value of said line probing signal; wherein said transmitter comprises a signal generator for generating said line probing signal at a first power level for a first predetermined time period and for generating said line probing signal at a second power level for a second predetermined time period later than said first predetermined time period; said line probing signal at said first power level comprising tones having a plurality of amplitude peaks at a power level above the average signal power level of a nominal transmission data signal so as to attain peak amplitudes in the non-linear region of said communication channel.
Claim 2
Dependent Claim
227 words
A modem, associated with a computer, for generating a line probing signal over a communication channel for use by a receiving modem to determine the non-linearity of the electrical characteristics of said communication channel comprising, in combination: a first bus for communicating with said computer; a transmitter for generating a finite plurality of different tones, said tones having a predetermined relative phase relationship; and a second bus for delivering signals, including said tones, to said communication channel, said tones being divided into a first group having a first predetermined phase and a second group having a second predetermined phase, said first and second predetermined phases having a predetermined phase relationship, said predetermined phase relationship arranged to substantially minimize the peak to root mean square average value of said line probing signal; wherein said transmitter comprises a signal generator for generating said line probing signal at a first power level for a first predetermined time period and for generating said line probing signal at a second power level for a second predetermined time period later than said first predetermined time period; said line probing signal at said first power level comprising tones having a plurality of amplitude peaks at a power level above the average signal power level of a nominal transmission data signal so as to attain peak amplitudes in the non-linear region of said communication channel.
Claim 3
Dependent Claim
20 words
A modem, as claimed in claim 1 wherein said predetermined phase relationship is defined substantially by 0 and 180 degrees.
Claim 4
Dependent Claim
90 words
A modem, as claimed in claim 2 wherein the frequency and phase relationships between said tones are substantially as set forth in the following table, wherein frequency is expressed in Hertz and phase is expressed in degrees: ______________________________________
Cosine Frequency, Hertz
Phase, Degrees
______________________________________
150 0
(reference)
300 0
450 180
600 180
750 0
1050 0
1350 0
1500 180
1650 0
1950 0
2100 0
2250 180
2400 0
2550 0
2700 0
2850 0
3000 180
3150 180
3300 0
3450 180
3600 180
3750 180.
______________________________________
Claim 5
Dependent Claim
87 words
A modem, as claimed in claim 2 wherein the frequency and phase relationships between said tones are substantially as set forth in the following table, wherein frequency is expressed in Hertz and phase is expressed in degrees: ______________________________________
Cosine Frequency, Hertz
Phase, Degrees
______________________________________
150 0
300 180
450 0
600 0
750 0
1050 0
1350 0
1500 0
1650 180
1950 0
2100 0
2250 180
2550 0
2700 180
2850 0
3000 180
3150 180
3300 180
3450 180
3600 0
3750 0.
______________________________________
Claim 6
Dependent Claim
17 words
A modem, as claimed in claim 1, wherein said first predetermined time period is approximately 160 milliseconds.
Claim 7
Dependent Claim
24 words
A modem, as claimed in claim 5, wherein the ratio of said first power level to said second power level is approximately 6 decibels.
Claim 8
Independent Claim
197 words
A method for a modem, associated with a computer, for generating a line probing signal over a communication channel for use in determining the non-linearity of the electrical characteristics of said communication channel comprising, in combination, the steps of: (a) generating a finite plurality of different tones, said tones (1) having a predetermined relative phase relationship and (2) being divided into a first group having a first predetermined phase and a second group having a second predetermined phase, said first and second predetermined phases having a predetermined phase relationship, said predetermined phase relationship arranged to substantially minimize the peak to root mean square average value of said line probing signal; (b) generating said line probing signal at a first power level for a first predetermined time period, said first power level being above the average signal power level of a nominal transmission data signal so as to attain peak amplitudes in the non-linear region of said communications channel, and generating said line probing signal at a second power level different from said first power level for a second predetermined time period later than said first predetermined time period; and (c) delivering said tones to said communication channel.
Claim 9
Independent Claim
197 words
A method for a modem, associated with a computer, for generating a line probing signal over a communication channel for use in determining the non-linearity of the electrical characteristics of said communication channel comprising, in combination, the steps of: (a) generating a finite plurality of different tones, said tones (1) having a predetermined relative phase relationship and (2) being divided into a first group having a first predetermined phase and a second group having a second predetermined phase, said first and second predetermined phases having a predetermined phase relationship, said predetermined phase relationship arranged to substantially minimize the peak to root mean square average value of said line probing signal; (b) generating said line probing signal at a first power level for a first predetermined time period, said first power level being above the average signal power level of a nominal transmission data signal so as to attain peak amplitudes in the non-linear region of said communications channel, and generating said line probing signal at a second power level different from said first power level for a second predetermined time period later than said first predetermined time period; and (c) delivering said tones to said communication channel.
Claim 10
Dependent Claim
20 words
A modem, as claimed in claim 7, wherein said predetermined phase relationship is defined substantially by 0 and 180 degrees.
Claim 11
Dependent Claim
90 words
A method, as claimed in claim 8, wherein the frequency and phase relationships between said tones are substantially as set forth in the following table, wherein frequency is expressed in Hertz and phase is expressed in degrees: ______________________________________
Cosine Frequency, Hertz
Phase, Degrees
______________________________________
150 0
(reference)
300 0
450 180
600 180
750 0
1050 0
1350 0
1500 180
1650 0
1950 0
2100 0
2250 180
2400 0
2550 0
2700 0
2850 0
3000 180
3150 180
3300 0
3450 180
3600 180
3750 180.
______________________________________
Claim 12
Dependent Claim
87 words
A method, as claimed in claim 8, wherein the frequency and phase relationships between said tones are substantially as set forth in the following table, wherein frequency is expressed in Hertz and phase is expressed in degrees: ______________________________________
Cosine Frequency, Hertz
Phase, Degrees
______________________________________
150 0
300 180
450 0
600 0
750 0
1050 0
1350 0
1500 0
1650 180
1950 0
2100 0
2250 180
2550 0
2700 180
2850 0
3000 180
3150 180
3300 180
3450 180
3600 0
3750 0.
______________________________________
Claim 13
Dependent Claim
17 words
A method, as claimed in claim 7, wherein said first predetermined time period is approximately 160 milliseconds.
Claim 14
Dependent Claim
24 words
A method, as claimed in claim 11, wherein the ratio of said first power level to said second power level is approximately 6 decibels.
References Cited (Backward Citations)
US5054034A
Cited
US5048054A
Cited
US5048056A
Cited
US5291520A
Cited
US5214637A
Cited
US5265151A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-05-07 | 1999-11-06 | 2000-05-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-05-07 | 2003-11-06 | 2004-05-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-05-07 | 2007-11-06 | 2008-05-07 | $7700.00 | Window Closed / Lapsed |