US5497398A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Multi-carrier transceiver
Assignee: TQ Delta LLC
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Filing: 1993-08-12
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Granted: 1996-03-05
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Expires: 2013-08-12
Abstract
Abstract A multi-carrier data transmission system utilizing lapped transforms. Information to be transmitted is divided into a plurality of channels that are coded using a transform that places information into narrow bandwidth channels. The system makes use of the superior properties of filter banks constructed with narrow-band lapped transforms to provide improved signal isolation between the data channels. A new form of lapped transformation that provides both narrow-band filtering and phase information is described. The transform utilizes two components to provide information on phase changes induced by errors on the communication link. The improved transform provides a means for correcting for phase shifts that occur on the communication link. The system has superior burst noise immunity compared to systems based on FFT's.
Inventors
- 👤 Michael A. Tzannes
- 👤 Marcos C. Tzannes
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-06 01:46
CPC Classifications
H; H04; H04L; H04L27/00; H04L27/26; H04L27/2601; H04L27/2626; H04L27/2627; H04L27/264; H04L27/26414; H04L27/2647; H04L27/2649; H04L27/26534; H04L27/26538
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
206 words
A system for communicating information over a communication link, said system comprising: means for receiving data symbols specifying said information; means for converting groups of M said data symbols to a plurality of time-domain samples, said convening means comprising means for storing the last W said data symbols received by said receiving means, where W is an integer multiple of M and M and W are greater than 1, and first correlation means for computing the correlation of said stored symbols with M vectors i A, for i=1, . . . , M, each said vector having W components; means for sequentially transmitting said time-domain symbols on said communication link, each said time-domain symbol being transmitted as an analog signal on said communication link; means for receiving said analog signals from said communication link and for convening said analog signals to digital values; means for storing the digital values corresponding to the last W said analog signals received; and second correlation means for computing the correlation of said stored digital values with M complex vectors i B+j i B', to obtain M modified data symbols S' i , for i=1, . . . , M, wherein i B and i B' are real valued, and j=√-1.
Claim 2
Independent Claim
206 words
A system for communicating information over a communication link, said system comprising: means for receiving data symbols specifying said information; means for converting groups of M said data symbols to a plurality of time-domain samples, said convening means comprising means for storing the last W said data symbols received by said receiving means, where W is an integer multiple of M and M and W are greater than 1, and first correlation means for computing the correlation of said stored symbols with M vectors i A, for i=1, . . . , M, each said vector having W components; means for sequentially transmitting said time-domain symbols on said communication link, each said time-domain symbol being transmitted as an analog signal on said communication link; means for receiving said analog signals from said communication link and for convening said analog signals to digital values; means for storing the digital values corresponding to the last W said analog signals received; and second correlation means for computing the correlation of said stored digital values with M complex vectors i B+j i B', to obtain M modified data symbols S' i , for i=1, . . . , M, wherein i B and i B' are real valued, and j=√-1.
Claim 3
Dependent Claim
28 words
The system of claim 1 wherein i B= i A and i B'=A/ , wherein, i A/ k = i A W-k for k=0 . . . W-1.
Claim 4
Dependent Claim
30 words
The system of claim 1 further comprising means for correcting said S' i for attenuation and phase shifts resulting from the transmission of said analog signals on said communication link.
Claim 5
Dependent Claim
47 words
The system of claim 3 wherein said correcting means comprises: means for computing the ratio of S' k /U k , where U k is the value of S' k obtained when all of the data symbols input to said receiving means have a known calibration value.
Claim 6
Dependent Claim
162 words
A receiver for use in system for use in system for communication information over a communication link, said receiver decoding a set of M symbols, S i , transmitted on said communication link as a sequence of analog signals obtained by computing the correlation between said symbols and a set of M vectors, i A, for i=1, . . . , M, said receiver comprising: means for receiving said analog signals from said communication link and for convening said analog signals to digital values; means for storing the digital values corresponding to the last W said analog signals received, where W is an integer multiple of M and M and W are greater than 1; and correlation means for computing the correlation of said stored digital values with M complex vectors i B+j i B', to obtain M modified data symbols S' i , for i=1, . . . , M, wherein i B and i B' are real valued, and j=√-1.
Claim 7
Dependent Claim
162 words
A receiver for use in system for use in system for communication information over a communication link, said receiver decoding a set of M symbols, S i , transmitted on said communication link as a sequence of analog signals obtained by computing the correlation between said symbols and a set of M vectors, i A, for i=1, . . . , M, said receiver comprising: means for receiving said analog signals from said communication link and for convening said analog signals to digital values; means for storing the digital values corresponding to the last W said analog signals received, where W is an integer multiple of M and M and W are greater than 1; and correlation means for computing the correlation of said stored digital values with M complex vectors i B+j i B', to obtain M modified data symbols S' i , for i=1, . . . , M, wherein i B and i B' are real valued, and j=√-1.
Claim 8
Dependent Claim
28 words
The system of claim 5 wherein i B= i A and i B'=A/ , wherein, i A/ k = i A W-k for k=0 . . . W-1.
References Cited (Backward Citations)
US5128964A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-03-05 | 1999-09-04 | 2000-03-05 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-03-05 | 2003-09-04 | 2004-03-05 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-03-05 | 2007-09-04 | 2008-03-05 | $7700.00 | Window Closed / Lapsed |