| 1. |
- KRISTENSSON, Martin, et al.
(författare)
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Co-channel interference rejection in a digital receiver
- 2000
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Patent (populärvet., debatt m.m.)abstract
- The present invention relates to a method for a digital receiver and a receiver exploiting second order statistics for adaptive co-channel interference rejection in wireless communication. It uses digitally I, in phase, and Q, quadrature, branches of a received transmitted signal as input to the receiver, a coarse synchronization and a coarse frequency offset compensation have being performed on the signal. It comprises a means for derotation, means for separation, means for filtering, means for estimating and means for detecting transmitted symbols in the received signal. The invention thereby improving co-channel rejection in wireless communication, thus making it possible to increase the number of communication channels for frequencies used.
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| 2. |
- Kristensson, Martin, et al.
(författare)
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Receiver
- 2003
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Patent (populärvet., debatt m.m.)abstract
- The present invention relates to a method for a digital receiver and a receiver exploiting second order statistics for adaptive co-channel interference rejection in wireless communication. It uses digitally I, in phase, and Q, quadrature, branches of a received transmitted signal as input to the receiver, a coarse synchronization and a coarse frequency offset compensation have being performed on the signal. It comprises a means for derotation, means for separation, means for filtering, means for estimating and means for detecting transmitted symbols in the received signal. The invention thereby improving co-channel rejection in wireless communication, thus making it possible to increase the number of communication channels for frequencies used.
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| 3. |
- Ottersten, Björn, 1961-, et al.
(författare)
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Spectrally efficient high capacity wireless communication systems with spatio-temporal processing
- 1998
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Patent (populärvet., debatt m.m.)abstract
- A wireless system includes a network of base stations for receiving uplink signals transmitted from a plurality of remote terminals and for transmitting downlink signals to said plurality of remote terminals using a plurality of channels. A plurality of antenna elements at each base station receives uplink signals, and a plurality of antenna elements at each base station for transmits downlink signals. A signal processor at each base station is connected to the receiving antenna elements and to the transmitting antenna elements for determining spatio-temporal signatures. Spatio-temporal multiplexing and demultiplexing functions are provided for each remote terminal antennae for each channel, and a multiple base station network controller optimizies network performance, whereby communication between the base stations and the plurality of remote terminals in each of the channels can occur simultaneously.
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| 4. |
- Roy, Richard H., et al.
(författare)
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Spatial division multiple access wireless communication systems
- 1992
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Patent (populärvet., debatt m.m.)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 ditinct 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.
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| 5. |
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| 6. |
- Yun, Louis C., et al.
(författare)
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Channel assignment and call admission control for spatial division multiple access communication systems
- 1996
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Patent (populärvet., debatt m.m.)abstract
- The methods for channel assignment and channel reassignment are suitable for SDMA systems that accommodate the dynamically adaptive spatial channel conditions and allow for more frequent reuse of conventional channels. Three methods for uplink channel assignment are described: a cost function method, a predictive method, and a hierarchical method. The cost function method computes a cost function for each conventional channel based on a weighted correlation matrix of spatial signatures (vectors) of active subscribers. A spatial channel is created for the selected conventional channel if it is in use. The predictive channel assignment method predicts the uplink received power and interference-plus-noise for each conventional channel. Either the conventional channel with the minimum interference-plus-noise level or the channel with the maximal SINR is selected and a spatial channel is also assigned if the selected channel is in use. The hierarchical method combines the cost function method and the cost function method. The downlink channel assignment method, when not constrained by the uplink channel assignment, assigns a conventional channel to a new connection by estimating the downlink interference-plus-noise level from a subscriber report, spatial signature and weight vector, and computing a predicted downlink received signal level. Three methods for call admission control include: a cost function method, a predictive method, and a load based channel assignment method.
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