US5515378A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Spatial division multiple access wireless communication systems
Assignee: Intel Corp
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Filing: 1991-12-12
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Granted: 1996-05-07
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Expires: 2011-12-12
Abstract
Abstract A method and apparatus for increasing the capacity and quality of wireless communication between a plurality of remote users and a base station is disclosed. Using measurements from an array of receiving antennas at the base station, parameters of multiple signals transmitted to the base station from a plurality of users in the same channel are calculated and used to obtain the positions and velocities of the users. The locations and other related signal parameters are used to calculate appropriate spatial demultiplexing strategies, reconstructing the individual transmitted signals from the receiver measurements and reducing interference to acceptable levels. This heretofore unavailable location information is used in solving the hand-off problem. This information is also used to calculate an appropriate spatial multiplexing strategy for simultaneous transmission of signals to users in the same channel. This can be the same as or distinct from the aforementioned receive channel. In combination, the transmit and receive systems establish multiple full-duplex links in the same channel by directively receiving and transmitting signals at the base stations only. This invention can also be implemented at the mobile sites to improve signal quality and to establish point-to-point communication links between multiple mobile users. Furthermore, implementation of both transmit and receive functions at the base station is not required. A receive-only system base station will still improve received signal quality and therefore capacity in addition to mitigating the hand-off problem.
Inventors
- 👤 Richard H. Roy, III
- 👤 Bjorn Ottersten
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 19:44
CPC Classifications
H; H04; H04B; H04B7/00; H04B7/02; H04B7/04; H04B7/06; H04B7/0697; H04B7/24; H04B7/26; H01; H01Q; H01Q1/00; H01Q1/12; H01Q1/22; H01Q1/24; H01Q1/241; H01Q1/246; H01Q3/00; H01Q3/26; H01Q3/2605; H01Q3/267; H04B17/00; H04B17/30; H04B17/309; H04B7/0408; H04B7/0491; H04B7/0613; H04B7/0615; H04B7/08; H04B7/0837; H04B7/0842; H04B7/0845; H04W; H04W16/00; H04W16/24; H04W16/28; H04W64/00; H04W84/00; H04W84/02; H04W84/022; H04W84/025; G; G01; G01S; G01S5/00; G01S5/02; G01S5/12
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
189 words
A wireless system including a base station for receiving uplink signals transmitted by users at different spatial locations comprising: receiving means including a plurality of receiving antennas at said base station for detecting combinations of arriving signals from said users, said receiving means further comprising plural multichannel receivers for obtaining said combinations of arriving signals from said receiving antennas for plural uplink channels from said users, each multichannel receiver having one channel for each uplink channel; processing means at said base station for processing said combinations of arriving signals, said processing means including means for determining a number of arriving signals in each of said uplink channels by employing statistical methods using eigenvalues of a covariance matrix calculated using said combinations of arriving signals, means for obtaining said parameters of said arriving signals including directions of arrival of said arriving signals, means for tracking user parameters including locations of said users from said parameters and said combinations of arriving signals, and spatial demultiplexing means for obtaining estimates of each of said uplink signals from said combinations of arriving signals and said parameters of arriving signals and said user parameters.
Claim 2
Dependent Claim
189 words
A wireless system including a base station for receiving uplink signals transmitted by users at different spatial locations comprising: receiving means including a plurality of receiving antennas at said base station for detecting combinations of arriving signals from said users, said receiving means further comprising plural multichannel receivers for obtaining said combinations of arriving signals from said receiving antennas for plural uplink channels from said users, each multichannel receiver having one channel for each uplink channel; processing means at said base station for processing said combinations of arriving signals, said processing means including means for determining a number of arriving signals in each of said uplink channels by employing statistical methods using eigenvalues of a covariance matrix calculated using said combinations of arriving signals, means for obtaining said parameters of said arriving signals including directions of arrival of said arriving signals, means for tracking user parameters including locations of said users from said parameters and said combinations of arriving signals, and spatial demultiplexing means for obtaining estimates of each of said uplink signals from said combinations of arriving signals and said parameters of arriving signals and said user parameters.
Claim 3
Dependent Claim
109 words
The wireless system as defined by claim 1 wherein said spatial demultiplexing means for obtaining said estimates of said uplink signals comprises: means for using said parameters of arriving signals and said user parameters and said combinations of arriving signals from said receiving antennas in each of said uplink channels for obtaining said arriving signals, means for associating said arriving signals in each of said uplink channels with said users in each of said uplink channels, and means for combining said arriving signals in each of said uplink channels associated with each of said users in each of said uplink channels to obtain said estimates of said uplink signals.
Claim 4
Dependent Claim
62 words
The wireless system as defined by claim 1 wherein said base station is one of a plurality of base stations, and further including means for assigning each user to one of said uplink channels, and means for selecting, at least one of said base stations for spatially demultiplexing said combinations of arriving signals to obtain transmitted uplink signals in said uplink channels.
Claim 5
Dependent Claim
112 words
A wireless system for communication of downlink signals from a base station in downlink channels to users at locations remote from said base station, said wireless system comprising: spatial multiplexing means for combining downlink signals to be transmitted from said base station in downlink channels to said users, and transmitting means having an input connected to said spatial multiplexing means for transmitting the combined downlink signals and including plural transmitting antennas and multichannel transmitters with one multichannel transmitter for each transmitting antenna and with one channel of each of said multichannel transmitters for each of said downlink channels, whereby said downlink signals are transmitted to said users in a spatially selective manner.
Claim 6
Dependent Claim
112 words
A wireless system for communication of downlink signals from a base station in downlink channels to users at locations remote from said base station, said wireless system comprising: spatial multiplexing means for combining downlink signals to be transmitted from said base station in downlink channels to said users, and transmitting means having an input connected to said spatial multiplexing means for transmitting the combined downlink signals and including plural transmitting antennas and multichannel transmitters with one multichannel transmitter for each transmitting antenna and with one channel of each of said multichannel transmitters for each of said downlink channels, whereby said downlink signals are transmitted to said users in a spatially selective manner.
Claim 7
Dependent Claim
185 words
A wireless system for communication of downlink signals from a base station to users at locations remote from said base station, said wireless system comprising: spatial multiplexing means for combining downlink signals to be transmitted from said base station in downlink channels to said users, and transmitting means having an input connected to said spatial multiplexing means for transmitting the combined downlink signals and including plural transmitting antennas and multichannel transmitters with one multichannel transmitter for each transmitting antenna and with one channel of each of said multichannel transmitters for each of said downlink channels, whereby said downlink signals are transmitted to said users in a spatially selective manner and, wherein said base station is one of a plurality of base stations, and wherein said spatial multiplexing means comprises: means for selecting at least one base station from said plurality of base stations for transmission of each of said downlink signals to each user, said spatial multiplexing means including means for combining said downlink signals for each of said downlink channels for each of said transmitting antennas at said selected at least one base station.
Claim 8
Dependent Claim
185 words
A wireless system for communication of downlink signals from a base station to users at locations remote from said base station, said wireless system comprising: spatial multiplexing means for combining downlink signals to be transmitted from said base station in downlink channels to said users, and transmitting means having an input connected to said spatial multiplexing means for transmitting the combined downlink signals and including plural transmitting antennas and multichannel transmitters with one multichannel transmitter for each transmitting antenna and with one channel of each of said multichannel transmitters for each of said downlink channels, whereby said downlink signals are transmitted to said users in a spatially selective manner and, wherein said base station is one of a plurality of base stations, and wherein said spatial multiplexing means comprises: means for selecting at least one base station from said plurality of base stations for transmission of each of said downlink signals to each user, said spatial multiplexing means including means for combining said downlink signals for each of said downlink channels for each of said transmitting antennas at said selected at least one base station.
Claim 9
Dependent Claim
22 words
The wireless system as defined by claim 5 and further including: means for assigning each of said users to a downlink channel.
Claim 10
Dependent Claim
322 words
A wireless system for full duplex communication of downlink signals and uplink signals between a base station and users physically remote from said base station, said wireless system comprising: receiving means at said base station for detecting combinations of arriving signals from said users in said uplink channel and including a plurality of receiving antennas and multichannel receivers with on multichannel receiver for each of said receiving antennas, each channel of each of said multichannel receivers dedicated to an uplink channel, processing means for processing said combinations of arriving signals in each uplink channel, said processing means comprising: means for determining the number of arriving signals in each of said uplink channels by employing statistical methods using eigenvalues of a covariance matrix calculated using said combinations of arriving signals, means for obtaining parameters of said arriving signals including directions of arrival of said arriving signals, and means for tracking user parameters including locations of said users from said parameters and said combinations of arriving signals, spatial demultiplexing means for obtaining estimates of the uplink signals in each uplink channel from said combinations of arriving signals and said parameters of arriving signals and said user parameters, spatial multiplexing means using said parameters of arriving signals and said user parameters for combining downlink signals from said base station to said users in at least one downlink channel, and transmitting means having an input connected to said spatial multiplexing means for transmitting the combined downlink signals and including a plurality of transmitting antennas and multichannel transmitters with one multichannel transmitter for each of said transmitting antennas, one channel of said multichannel transmitters dedicated to a downlink channel and to the spatial transmission of said downlink signals to said users in said at least one downlink channel, whereby reception of multiple uplink signals in multiple uplink channels from said users and transmission of multiple downlink signals in multiple downlink channels to said users can occur simultaneously.
Claim 11
Dependent Claim
322 words
A wireless system for full duplex communication of downlink signals and uplink signals between a base station and users physically remote from said base station, said wireless system comprising: receiving means at said base station for detecting combinations of arriving signals from said users in said uplink channel and including a plurality of receiving antennas and multichannel receivers with on multichannel receiver for each of said receiving antennas, each channel of each of said multichannel receivers dedicated to an uplink channel, processing means for processing said combinations of arriving signals in each uplink channel, said processing means comprising: means for determining the number of arriving signals in each of said uplink channels by employing statistical methods using eigenvalues of a covariance matrix calculated using said combinations of arriving signals, means for obtaining parameters of said arriving signals including directions of arrival of said arriving signals, and means for tracking user parameters including locations of said users from said parameters and said combinations of arriving signals, spatial demultiplexing means for obtaining estimates of the uplink signals in each uplink channel from said combinations of arriving signals and said parameters of arriving signals and said user parameters, spatial multiplexing means using said parameters of arriving signals and said user parameters for combining downlink signals from said base station to said users in at least one downlink channel, and transmitting means having an input connected to said spatial multiplexing means for transmitting the combined downlink signals and including a plurality of transmitting antennas and multichannel transmitters with one multichannel transmitter for each of said transmitting antennas, one channel of said multichannel transmitters dedicated to a downlink channel and to the spatial transmission of said downlink signals to said users in said at least one downlink channel, whereby reception of multiple uplink signals in multiple uplink channels from said users and transmission of multiple downlink signals in multiple downlink channels to said users can occur simultaneously.
Claim 12
Dependent Claim
95 words
The wireless system as defined by claim 7 wherein said spatial demultiplexing means comprise: means for using said parameters and said combinations of arriving signals from said receiving antennas in each of said uplink channels for reducing channel interference and noise, means for associating said arriving signals in each of said uplink channels with said users in each of said uplink channels, and means for combining said arriving signals in each of said uplink channels associated with each of said users in each of said uplink channels to obtain said estimates of said uplink signals.
Claim 13
Dependent Claim
80 words
The wireless system as defined by claim 7 wherein said base station is one of a plurality of base stations, and further including means for selecting at least one base station from said plurality of base stations for transmission of each of said downlink signals to each user, said spatial multiplexing means including means for combining said downlink signals for each of said downlink channels and for each of said transmitting antennas at said selected at least one base station.
Claim 14
Dependent Claim
62 words
The wireless system as defined by claim 7 wherein said base station is one of a plurality of base stations, and further including means for assigning each of said users to an uplink channel, and means for selecting at least one of said base stations for spatially demultiplexing said measurements to obtain said estimates of said uplink signals in said uplink channel.
Claim 15
Dependent Claim
62 words
The wireless system as defined by claim 7 wherein said base station is one of a plurality of base stations, and further including means for assigning each of said users to a downlink channel, and means for selecting at least one of said base stations for transmitting each of said downlink signals to each of said users in an assigned downlink channel.
References Cited (Backward Citations)
US3774209A
Cited
US3704465A
Cited
US3798645A
Cited
US3852749A
Cited
US3946385A
Cited
US4085319A
Cited
US4128740A
Cited
US4434505A
Cited
US4475010A
Cited
US4626859A
Cited
US4796291A
Cited
US4639914A
Cited
US4829554A
Cited
US4972151A
Cited
US4750147A
Cited
US4965732A
Cited
US4737794A
Cited
US4742356A
Cited
US4947452A
Cited
US4955082A
Cited
US4989204A
Cited
US4837800A
Cited
US4910794A
Cited
US4965849A
Cited
US4965850A
Cited
US5052799A
Cited
GB2237706A
Cited
US5159593A
Cited
US5260968A
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 |