US6144711A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spatio-temporal processing for communication
Assignee: Cisco Technology Inc
•
Filing: 1997-08-27
•
Granted: 2000-11-07
•
Expires: 2017-08-27
Abstract
Abstract A space-time signal processing system with advantageously reduced complexity. The system may take advantage of multiple transmitter antenna elements and/or multiple receiver antenna elements, or multiple polarizations of a single transmitter antenna element and/or single receiver antenna element. The system is not restricted to wireless contexts and may exploit any channel having multiple inputs or multiple outputs and certain other characteristics. Multi-path effects in a transmission medium cause a multiplicative increase in capacity.
Inventors
- 👤 Gregory G. Raleigh
- 👤 Vincent K. Jones, IV
- 👤 Michael A. Pollack
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 14:23
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/02; H04B7/04; H04B7/06; H04B7/0613; H04B7/0615; H04B7/0619; H04B7/0621; H04B7/0626; H04B7/0658; H04B7/068; H04B7/08; H04B7/0837; H04B7/0842; H04B7/0848; H04B7/0854; H04L; H04L1/00; H04L1/004; H04L1/0041; H04L1/0056; H04L1/0057; H04L1/0059; H04L1/006; H04L1/0064; H04L1/0065; H04L1/0071; H04L1/02; H04L1/06; H04L1/0606; H04L1/0618; H04L25/00; H04L25/02; H04L25/0202; H04L25/0204; H04L25/021; H04L25/0212; H04L25/024; H04L25/0242; H04L25/03; H04L25/03006; H04L25/03343; H04L27/00; H04L27/26; H04L27/2601; H04L27/2626; H04L27/2647; H04L5/00; H04L5/0001; H04L5/0028; H04L5/003; H04L5/0044; H04L5/0046; H04B1/00; H04B1/06; H04B1/10; H04B1/1081; H04B7/0413; H04B7/0426; H04B7/0434; H04B7/0443; H04B7/0456; H04B7/046; H04B7/0469; H04B7/0667; H04B7/0669; H04B7/10; H04L1/0045; H04L1/0054; H04L1/12; H04L1/16; H04L1/18; H04L1/1812; H04L2025/0335; H04L2025/03375; H04L2025/03414; H04L2025/03426; H04L2025/03777; H04L2025/03802; H04L25/03178; H04L25/03305; H04L25/03331; H04L5/0003; H04L5/0005; H04L5/0007; H04L5/0014; H04L5/0023; H04W; H04W16/00; H04W16/24; H04W16/28; H04W72/00; H04W88/00; H04W88/02; H04W88/08
Claims Analysis
Total Claims: 35
Claim 1
Independent Claim
119 words
In a digital communication system, a method for receiving via a plurality of outputs from a channel, said method comprising: providing a time domain substantially orthogonalizing procedure to divide said channel into output bins; providing one or more spatial directions for communication defined by corresponding weightings among said channel outputs wherein each output bin has at least one associated spatial direction, said weightings defining said one or more spatial directions so that each spatial direction corresponds to communication via more than one channel output; and receiving information via subchannels of said channel by employing at least two independent parallel applications of said time domain substantially orthogonalizing procedure, each subchannel defined by a combination of output bin and spatial direction.
Claim 2
Dependent Claim
119 words
In a digital communication system, a method for receiving via a plurality of outputs from a channel, said method comprising: providing a time domain substantially orthogonalizing procedure to divide said channel into output bins; providing one or more spatial directions for communication defined by corresponding weightings among said channel outputs wherein each output bin has at least one associated spatial direction, said weightings defining said one or more spatial directions so that each spatial direction corresponds to communication via more than one channel output; and receiving information via subchannels of said channel by employing at least two independent parallel applications of said time domain substantially orthogonalizing procedure, each subchannel defined by a combination of output bin and spatial direction.
Claim 3
Dependent Claim
69 words
The method of claim 1 wherein receiving information comprises: receiving input time domain symbols via said channel outputs; applying said time domain substantially orthogonalizing procedure to said input time domain symbols independently for each of said channel outputs; and applying ones of said weightings corresponding to each of said output bins to results of said time domain substantially orthogonalizing procedure to obtain symbols transmitted via each of said subchannels.
Claim 4
Dependent Claim
43 words
The method of claim 1 wherein receiving information comprises receiving information in subchannels defined by said output bins and at least two spatial directions associated with each of said output bins, said spatial directions being chosen independently for each of said output bins.
Claim 5
Dependent Claim
21 words
The method of claim 3 wherein said at least two spatial directions are mutually orthogonal for each of said output bins.
Claim 6
Dependent Claim
60 words
The method of claim 3 wherein receiving information comprises: receiving time domain symbols via said channel outputs; for each of said channel outputs, independently applying said time domain substantially orthogonalizing procedure to said received input time domain symbols; and applying said weightings to results of said time domain substantially orthogonalizing procedure to obtain symbols transmitted via each of said subchannels.
Claim 7
Dependent Claim
26 words
The method of claim 5 wherein said weightings are selected according to singular value decompositions of matrices characterizing communication via each output bin of said channel.
Claim 8
Dependent Claim
20 words
The method of claim 5 further comprising applying a decoding procedure to said symbols transmitted via each of said subchannels.
Claim 9
Dependent Claim
22 words
The method of claim 3 wherein said at least two spatial directions are not mutually orthogonal for each of said output bins.
Claim 10
Dependent Claim
90 words
The method of claim 8 wherein receiving information comprises: receiving time domain symbols via said channel outputs; for each of said channel outputs, applying said weightings to said time domain symbols to obtain results corresponding to each of said spatial directions; applying said time domain substantially orthogonalizing procedure to said results independently for each of said spatial directions to obtain symbols transmitted via each of said subchannels; and decoding said symbols transmitted via each of said subchannels according to a coding scheme optimized to take advantage of multiple spatial directions.
Claim 11
Dependent Claim
30 words
The method of claim 1 wherein said time domain substantially orthogonalizing procedure belongs to one of a group consisting of a Fast Fourier Transform and an inverse Fast Fourier Transform.
Claim 12
Dependent Claim
24 words
The method of claim 10 wherein said Fast Fourier Transform or said inverse Fast Fourier Transform is preceded by removal of a cyclic prefix.
Claim 13
Dependent Claim
28 words
The method of claim 1 wherein said channel comprises a wireless channel and said plurality of channel outputs are associated with a corresponding plurality of receiver antenna elements.
Claim 14
Dependent Claim
14 words
The method of claim 12 wherein said plurality of receiver antenna elements are co-located.
Claim 15
Dependent Claim
16 words
The method of claim 12 wherein said plurality of receiver antenna elements are at disparate locations.
Claim 16
Dependent Claim
122 words
The method of claim 1 further comprising: receiving via a particular one of said channel outputs, at least v frequency domain training symbols transmitted via a particular input to said channel in a single burst, v being an extent in symbol periods of a duration of significant terms of an impulse response of a channel component coupling said particular channel input and said particular channel output; applying an inverse of said time domain substantially orthogonalizing procedure to said received at least v frequency domain training symbols to obtain a time domain response for said channel component; and applying said time domain substantially orthogonalizing procedure to a zero-padded version of said time domain response to obtain a frequency response for said channel component.
Claim 17
Dependent Claim
133 words
A receiver system for receiving via a plurality of outputs from a channel, said receiver system comprising: at least one processing element that applies a time domain substantially orthogonalizing procedure to divide said channel into output bins; a spatial processor employing weightings among said channel outputs to define spatial directions wherein each output bin has at least one associated spatial direction, said weightings defining said one or more spatial directions so that each spatial direction corresponds to communication via more than one channel output; and wherein said receiver system receives information via subchannels of said channel, by employing at least two independent parallel applications of said time domain substantially orthogonalizing procedure by said at least one processing element, each of said subchannels being defined by a combination of output bin and spatial direction.
Claim 18
Dependent Claim
133 words
A receiver system for receiving via a plurality of outputs from a channel, said receiver system comprising: at least one processing element that applies a time domain substantially orthogonalizing procedure to divide said channel into output bins; a spatial processor employing weightings among said channel outputs to define spatial directions wherein each output bin has at least one associated spatial direction, said weightings defining said one or more spatial directions so that each spatial direction corresponds to communication via more than one channel output; and wherein said receiver system receives information via subchannels of said channel, by employing at least two independent parallel applications of said time domain substantially orthogonalizing procedure by said at least one processing element, each of said subchannels being defined by a combination of output bin and spatial direction.
Claim 19
Dependent Claim
84 words
The receiver system of claim 16 further comprising: a system input that receives time domain input symbols via said channel outputs; and wherein said at least one processing element applies said time domain substantially orthogonalizing procedure to said time domain input symbols independently for each of said channel outputs; and wherein said spatial processor applies ones of said weightings corresponding to each of said output bins to results of said time domain substantially orthogonalizing procedure to obtain symbols transmitted via each of said subchannels.
Claim 20
Dependent Claim
42 words
The receiver system of claim 16 wherein said receiver system receives information in subchannels defined by said output bins and at least two spatial directions associated with each of said output bins, each of said output bins having identical associated spatial directions.
Claim 21
Dependent Claim
44 words
The receiver system of claim 16 wherein said receiver system receives information in subchannels defined by said output bins and at least two spatial directions associated with each of said output bins, said spatial directions being chosen independently for each of said output bins.
Claim 22
Dependent Claim
22 words
The receiver system of claim 19 wherein said at least two spatial directions are mutually orthogonal for each of said output bins.
Claim 23
Dependent Claim
74 words
The receiver system of claim 19 further comprising: a system input that receives time domain symbols via said channel outputs; and wherein said at least one processing element, for each of said channel outputs, independently applies said time domain substantially orthogonalizing procedure to said received time domain symbols; and wherein said spatial processor applies said weightings to results of said time domain substantially orthogonalizing procedure to obtain symbols transmitted via each of said subchannels.
Claim 24
Dependent Claim
27 words
The receiver system of claim 21 wherein said weightings are selected according to singular value decompositions of matrices characterizing communication via each output bin of said channel.
Claim 25
Dependent Claim
25 words
The receiver system of claim 21 further comprising a decoding system that applies a decoding procedure to said symbols transmitted via each of said subchannels.
Claim 26
Dependent Claim
23 words
The receiver system of claim 19 wherein said at least two spatial directions are rot mutually orthogonal for each of said output bins.
Claim 27
Dependent Claim
117 words
The receiver system of claim 24 further comprising: a system input that receives time domain symbols via said channel outputs; and wherein said spatial processor, for each of said channel outputs, applies said weightings to said time domain symbols to obtain result symbols corresponding to each of said spatial directions; and wherein said at least one processing element applies said time domain substantially orthogonalizing procedure to said result symbols independently for each of said spatial directions to obtain symbols transmitted via each of said subchannels; and wherein said receiver system further comprises: a decoding system that decodes symbols transmitted via each of said subchannels according to a coding scheme optimized to take advantage of multiple spatial directions.
Claim 28
Dependent Claim
31 words
The receiver system of claim 16 wherein said time domain substantially orthogonalizing procedure belongs to one of a group consisting of a Fast Fourier Transform and an inverse Fast Fourier Transform.
Claim 29
Dependent Claim
25 words
The receiver system of claim 26 wherein said Fast Fourier Transform or said inverse Fast Fourier Transform is preceded by removal of a cyclic prefix.
Claim 30
Dependent Claim
29 words
The receiver system of claim 16 wherein said channel comprises a wireless channel and said plurality of channel outputs are associated with a corresponding plurality of receiver antenna elements.
Claim 31
Dependent Claim
15 words
The receiver system of claim 28 wherein said plurality of receiver antenna elements are co-located.
Claim 32
Dependent Claim
17 words
The receiver system of claim 28 wherein said plurality of receiver antenna elements are at disparate locations.
Claim 33
Dependent Claim
123 words
The receiver system of claim 16 further comprising: a channel estimation processor that receives via a particular one of said channel outputs, at least v frequency domain training symbols transmitted via a particular input to said channel, v being an extent in symbol periods of a duration of significant items of an impulse response of channel component coupling said particular channel input and said particular channel, applies an inverse of said time domain substantially orthogonalizing procedure to said received at least v frequency domain training symbols to obtain a time domain response for said channel component, and that applies said time domain substantially orthogonalizing procedure to a zero-padded version of said time domain response to obtain a frequency response for said channel component.
Claim 34
Dependent Claim
142 words
A receiver system that receives a burst of time domain symbols via an output of a channel, said receiver system comprising: at least one processing element that performs a time domain substantially orthogonalizing procedure on said burst of time domain symbols to recover a bust of frequency domain symbols; and a channel estimation processor that receives at least v training symbols belonging to said burst of frequency domain symbols, v being an extent in symbol periods of a duration of significant terms of an impulse response of said channel, applies an inverse of said time domain substantially orthogonalizing procedure to said received at least v training symbols to obtain a time domain response for said channel, and that applies said time domain substantially orthogonalizing procedure to a zero-padded version of said time domain response to obtain a frequency response for said channel.
Claim 35
Dependent Claim
142 words
A receiver system that receives a burst of time domain symbols via an output of a channel, said receiver system comprising: at least one processing element that performs a time domain substantially orthogonalizing procedure on said burst of time domain symbols to recover a bust of frequency domain symbols; and a channel estimation processor that receives at least v training symbols belonging to said burst of frequency domain symbols, v being an extent in symbol periods of a duration of significant terms of an impulse response of said channel, applies an inverse of said time domain substantially orthogonalizing procedure to said received at least v training symbols to obtain a time domain response for said channel, and that applies said time domain substantially orthogonalizing procedure to a zero-padded version of said time domain response to obtain a frequency response for said channel.
References Cited (Backward Citations)
US4337376A
Cited
EP0253465A1
Cited
EP0253465B1
Cited
US4710944A
Cited
US5134715A
Cited
US5228025A
Cited
US5315584A
Cited
US5548819A
Cited
US5515378A
Cited
US5592490A
Cited
US5642353A
Cited
US5345599A
Cited
US5510799A
Cited
US5479444A
Cited
US5634199A
Cited
US5471647A
Cited
US5479447A
Cited
US5566209A
Cited
WO1995022873A2
Cited
US5537435A
Cited
US5752173A
Cited
US5691727A
Cited
WO1996030964A1
Cited
US5649287A
Cited
US5809019A
Cited
WO1998009395A1
Cited
WO1998009381A1
Cited
US5905721A
Cited
US5886988A
Cited
US5966094A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 2003-11-07 | 2004-05-08 | 2004-11-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2007-11-07 | 2008-05-08 | 2008-11-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2011-11-07 | 2012-05-08 | 2012-11-07 | $7700.00 | Window Closed / Lapsed |