摘要:
A method and apparatus of scheduling and transmitting uplink packets within uplink sub-frames of a wireless system is disclosed. The method includes determining a size of a standard data unit, and determining if the standard data unit can be transmitted within a single sub-channel of an uplink frame by comparing the size of the standard data unit with a number of bits that can be transmitted within the uplink frame as determined by an uplink quality. If the standard data unit is too large to be transmitted within a single sub-channel of an uplink frame, then the standard data unit is divided into sub-data units. The sub-data units are transmitted over multiple uplink frames.
摘要:
A method and apparatus of scheduling and transmitting uplink packets within uplink sub-frames of a wireless system is disclosed. The method includes determining a size of a standard data unit, and determining if the standard data unit can be transmitted within a single sub-channel of an uplink frame by comparing the size of the standard data unit with a number of bits that can be transmitted within the uplink frame as determined by an uplink quality. If the standard data unit is too large to be transmitted within a single sub-channel of an uplink frame, then the standard data unit is divided into sub-data units. The sub-data units are transmitted over multiple uplink frames.
摘要:
A method and apparatus of scheduling and transmitting uplink packets within uplink sub-frames of a wireless system is disclosed. The method includes determining a size of a standard data unit, and determining if the standard data unit can be transmitted within a single sub-channel of an uplink frame by comparing the size of the standard data unit with a number of bits that can be transmitted within the uplink frame as determined by an uplink quality. If the standard data unit is too large to be transmitted within a single sub-channel of an uplink frame, then the standard data unit is divided into sub-data units. The sub-data units are transmitted over multiple uplink frames.
摘要:
Embodiments disclose a method of coordinating reception of uplink transmissions in order to reduce interference among transceivers in an OFDM wireless transmission system, or similar communication system, including a number of receivers communicating with one or more basestations in cell or sector arrangements. A basestation within each sector includes an uplink coordinated reception process that imposes coordinated reception techniques across sector or cell boundaries in order to improve uplink transmission quality between target terminals and basestations within each sector.
摘要:
Embodiments described herein include methods for improving the SINR, and therefore communication quality or rate, in the downlink of a cellular communication system. In an embodiment, the system is an orthogonal-frequency-division multiple-access (OFDMA) system. In an embodiment, a set of terminals is designated a coordinated-transmission group. The set of terminal is chosen such that the slot-allocations of the set are given special treatment to alleviate interference from other sectors or cells. In an embodiment, “zones” defined in the WiMax standard are “repurposed” to handle the coordinated-transmission, although the zone was originally intended for another purpose.
摘要:
A wireless communications adapts its mode of operation between spatial multiplexing and non-spatial multiplexing in response to transmission-specific variables. An embodiment of a wireless communications system for transmitting information between a base transceiver station and a subscriber unit includes mode determination logic. The mode determination logic is in communication with the base transceiver station and the subscriber unit. The mode determination logic determines, in response to a received signal, if a subscriber datastream should be transmitted between the base transceiver station and the subscriber unit utilizing spatial multiplexing or non-spatial multiplexing. In an embodiment, the mode determination logic has an input for receiving a measure of a transmission characteristic related to the received signal. In an embodiment, the mode determination logic includes logic for comparing the measured transmission characteristic to a transmission characteristic threshold and for selecting one of spatial multiplexing and non-spatial multiplexing in response to the comparison of the measured transmission characteristic to the transmission characteristic threshold. In an embodiment, the transmission characteristic includes at least one of delay spread, post-processing signal-to-noise ratio, cyclical redundancy check (CRC) failure, residual inter-symbol interference, mean square error, coherence time, and path loss. By adapting the mode of operation in response to transmission-specific variables, the use of spatial multiplexing can be discontinued in unfavorable conditions. Additionally, because the wireless communications system can adapt its mode of operation between spatial multiplexing and non-spatial multiplexing, the communications system is compatible with both subscriber units that support spatial multiplexing and subscriber units that do not support spatial multiplexing.
摘要:
A method is disclosed for using feedback to reduce crosstalk between mobile receivers in a wireless communications system comprising an adaptive transmitting antenna array. Feedback signals from the receivers are time-averaged and used to calculate a set of weight vectors that minimize crosstalk and maximize desired signal without requiring burdensome feedback rates. Beamforming diversity is combined with feedback through the use of diversity vectors. The preferred embodiment includes a method for obtaining the required feedback by exploiting the SAT circuitry present in the AMPS system currently in use. Consequently, the method may be implemented without modification to existing cellular phone handsets.
摘要:
Interference between multiple users operating under multiuser diversity within a coherence bandwidth in an OFDMA system is reduced by spreading out the users' transmission symbols randomly in time within the coherence bandwidth. When transmission symbols are randomly dispersed, the variance of interference between users in the same sub-band is reduced on average.
摘要:
Embodiments described herein include methods for improving the SINR, and therefore communication quality or rate, in the downlink of a cellular communication system. In an embodiment, the system is an orthogonal-frequency-division multiple-access (OFDMA) system. In an embodiment, a set of terminals is designated a coordinated-transmission group. The set of terminal is chosen such that the slot-allocations of the set are given special treatment to alleviate interference from other sectors or cells. All terminals within a coordination group generally use the same slot, but embodiments are not so limited.
摘要:
Communication systems and methods are described in which multiple transmit signals are generated from an input stream or signal. The communication systems and methods, collectively referred to as antenna virtualization or virtual antenna systems, generate from each input stream multiple transmit signals that when driven into multiple antennas create a radiation pattern that effectively appears to originate from a single antenna. The communications operations include receiving at least one input stream. Multiple transmit signals are generated from the received input stream; the number of transmit signals generated is greater than the number of received input streams. Generation of the transmit signals involves transforming the input stream. The transforming includes applying one or more of a variable delay, a phase shift, and signal shaping to information of the input stream. The transmit signals are transmitted by a separate antenna of an antenna system.