MIMO communication system and transmission station
AssigneeFujitsu Limited
InventorDai Kimura
Life of this patent
Estimating the term…
Abstract
An imbalanced amplitude is produced to a pair of weighing factors (U1,1 and U1,2, U2,1 and U2,2) with respect to the transmission streams multiplexed to any of the plurality of transmission antennas. Thus, the increase in PAPR in a preceding MIMO system can be prevented.
Claims20
A multi-input multi-output (MIMO) communication system including a transmission station that transmits a plurality of transmission streams from a plurality of transmission antennas and a reception station that receives the transmission streams with a plurality of reception antennas and reproduces the respective transmission streams, the MIMO communication system comprising:
- multipliers that multiply weighting factors by the respective received transmission streams;
- and
- a controller that produces an imbalanced amplitude between a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein
- the controller sets, as the weighting factor, a unitary matrix or a submatrix of the unitary matrix in which a number of rows corresponds to a number of the transmission streams and a number of columns corresponds to a number of the transmission antennas.
A multi-input multi-output (MIMO) communication system including a transmission station that transmits a plurality of transmission streams from a plurality of transmission antennas and a reception station that receives the transmission streams with a plurality of reception antennas and reproduces the respective transmission streams, the MIMO communication system comprising:
- multipliers that multiply weighting factors by the respective received transmission streams;
- and
- a controller that produces an imbalanced amplitude between a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein the controller sets, as the weighing factor, an element of a row to which the imbalanced amplitude is produced between the elements of each row in a unitary matrix constituting a precoding matrix corresponding to the number of the transmission streams.
A multi-input multi-output (MIMO) communication system including a transmission station that transmits a plurality of transmission streams from a plurality of transmission antennas and a reception station that receives the transmission streams with a plurality of reception antennas and reproduces the respective transmission streams, the MIMO communication system comprising:
- multipliers that multiply weighting factors by the respective received transmission streams;
- and
- a controller that produces an imbalanced amplitude between a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein
- the imbalanced amplitude is controlled in accordance with the transmission power of the transmission station, and wherein the imbalanced amplitude is controlled to increase the degree of the imbalance as the transmission power is smaller.
A multi-input multi-output (MIMO) communication system including a transmission station that transmits a plurality of transmission streams from a plurality of transmission antennas and a reception station that receives the transmission streams with a plurality of reception antennas and reproduces the respective transmission streams, the MIMO communication system comprising:
- multipliers that multiply weighting factors by the respective received transmission streams;
- and
- a controller that produces an imbalanced amplitude between a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein
- the imbalanced amplitude is optimized based on a characteristic of an amplifier that amplifies the transmission power of the transmission station, and wherein
- the transmission station has a transmitter that reports the imbalanced amplitude to the reception station, and
- the reception station has a controller that produces the imbalanced amplitude reported from the transmission station between the elements in each row in an unitary matrix constituting a precoding matrix included in a code book held by the reception station, the code book comprising a plurality of sets of the unitary matrix corresponding to the number of the transmission streams.
A transmission station in a multi-input multi-output (MIMO) communication system including the transmission station that transmits a plurality of transmission streams with a plurality of transmission antennas and a reception station that receives the transmission streams with a plurality of reception antennas and reproduces the respective received transmission streams, the transmission station comprising:
- a weighting factor multiplier that multiplies a weighting factor by the respective transmission streams;
- and
- a controller operable to produce an imbalanced amplitude to a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein
- the controller sets, as the weighting factor, a unitary matrix or a submatrix of the unitary matrix in which a number of rows corresponds to a number of the transmission streams and a number of columns corresponds to a number of the transmission antennas.
A transmission station in a multi-input multi-output (MIMO) communication system including the transmission station that transmits a plurality of transmission streams with a plurality of transmission antennas and a reception station that receives the transmission streams with a Plurality of reception antennas and reproduces the respective received transmission streams, the transmission station comprising:
- a weighting factor multiplier that multiplies a weighting factor by the respective transmission streams;
- and
- a controller operable to produce an imbalanced amplitude to a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein the controller sets, as the weighing factor, an element of a row to which the imbalanced amplitude is produced between the elements of each row in a unitary matrix constituting a precoding matrix corresponding to the number of the transmission streams.
A transmission station in a multi-input multi-output (MIMO) communication system including the transmission station that transmits a plurality of transmission streams with a plurality of transmission antennas and a reception station that receives the transmission streams with a Plurality of reception antennas and reproduces the respective received transmission streams, the transmission station comprising:
- a weighting factor multiplier that multiplies a weighting factor by the respective transmission streams;
- and
- a controller operable to produce an imbalanced amplitude to a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein
- the controller controls the imbalanced amplitude in accordance with the transmission power of the transmission station, and wherein the imbalanced amplitude is controlled to increase the degree of the imbalance as the transmission power is smaller.
A transmission station in a multi-input multi-output (MIMO) communication system including the transmission station that transmits a plurality of transmission streams with a plurality of transmission antennas and a reception station that receives the transmission streams with a Plurality of reception antennas and reproduces the respective received transmission streams, the transmission station comprising:
- a weighting factor multiplier that multiplies a weighting factor by the respective transmission streams;
- and
- a controller operable to produce an imbalanced amplitude to a pair of the weighting factors with respect to the respective transmission streams multiplexed to any of the transmission antennas, wherein
- the imbalanced amplitude is optimized based on a characteristic of an amplifier that amplifies the transmission power of the transmission streams, and wherein the controller reports the imbalanced amplitude to the reception station in order to reflect the imbalanced amplitude between the elements of each row in an unitary matrix constituting a precoding matrix included in a code book held by the reception station, the code book comprising a plurality of sets of the unitary matrix corresponding to the number of the transmission streams.
Dependencies are inferred from the claim text.