Method for link adaptation
View Patent ↗Systems and methods for optimizing transmission of a plurality of data streams on a multiple-input multiple-output channel are described. The systems and methods for optimizing reduce the multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme and transmit the plurality of data streams based on the single-input single-output channel for the transmission scheme. Systems and methods for optimizing the transfer of data for any number of transmit and receive antennas are described.
1. A method of a transmitter optimizing transmission of a plurality of data streams on a multiple-input multiple-output channel, the method comprising:
reducing the multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme, comprising;
obtaining a first channel matrix of the multiple-input-multiple-output transmission channel;
converting the first channel matrix to an equivalent second channel matrix for each transmission scheme, the multiple-input-multiple-output transmission channel using a plurality of transmission schemes,
performing a singular value decomposition on the second channel matrix of each transmission scheme to obtain a channel gain of each transmission scheme using a predetermined procedure;
calculating a total channel gain of each transmission scheme to obtain the equivalent single-input single-output channel for the transmission scheme; and
repeating steps (a) to (d) on the plurality of transmission schemes to obtain a plurality of total channel gains,
wherein a first channel gain for each transmission scheme is computed as a product of a minimum value of the first channel gain for each transmission scheme and a signal-to-noise ratio: and wherein the data stream that has been affected most in the multiple-input multiple-output channel corresponds to the minimum value; and
the transmitter transmitting the plurality of data streams based on the single-input single-output channel for the transmission scheme.
2. The method of claim 1 , wherein the transmitting further comprises selecting a best transmission scheme based on a predetermined condition applied to the plurality of total channel gains.
3. The method of claim 2 , wherein the selecting further comprises choosing the best transmission scheme based on a highest value of the equivalent single-input single-output channel for the transmission scheme.
4. The method of claim 1 , wherein the performing a singular value decomposition further comprises substituting the second channel matrix with a product of a first unitary matrix corresponding to the second channel matrix of each transmission scheme, a diagonal matrix representing the channel gains of the transmission scheme and a second unitary matrix corresponding to the second channel matrix of each transmission scheme.
5. The method of claim 1 , wherein the data stream that has been affected most in the multiple-input multiple-output channel corresponds to the minimum value.
6. A method of a transmitter optimizing transmission of a plurality of data streams on a multiple-input multiple-output channel, the method comprising:
reducing the multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme, comprising;
obtaining a first channel matrix of the multiple-input-multiple-output transmission channel;
converting the first channel matrix to an equivalent second channel matrix for each transmission scheme, the multiple-input-multiple-output transmission channel using a plurality of transmission schemes,
performing a singular value decomposition on the second channel matrix of each transmission scheme to obtain a channel gain of each transmission scheme using a predetermined procedure;
calculating a total channel gain of each transmission scheme to obtain the equivalent single-input single-output channel for the transmission scheme; and
repeating steps (a) to (d) on the plurality of transmission schemes to obtain a plurality of total channel gains,
wherein the calculating a total channel gain of each transmission scheme further comprises adding the channel gain of the transmission scheme, a forward error correction gain of the transmission scheme and a modulation order gain of the transmission scheme;
the transmitter transmitting the plurality of data streams based on the single-input single-output channel for the transmission scheme.
7. The method of claim 1 , wherein the transmitting end has at least two transmit antennas.
8. The method of claim 1 , wherein the receiving end has at least one receive antenna.
9. The method of claim 1 , wherein the link adaptation is optimized based on at least one of a throughput required, packet error correction rate, or both.
10. The method of claim 1 , wherein the link adaptation is optimized for a forward error correction gain, a modulation order gain and a space-time coding gain.
11. A system comprising a link adaptation unit coupled to a processor, the processor configured to reduce a multiple-input multiple-output channel for each transmission scheme to an equivalent single-input single-output channel for the transmission scheme and configured to control transmission of a plurality of data streams over the multiple-input multiple-output channel based on the single-input single-output channel for the transmission scheme, wherein the transmission is optimized, wherein the processor is configured to:
obtain a first channel matrix of the multiple-input-multiple-output transmission channel;
convert the first channel matrix to an equivalent second channel matrix for each transmission scheme, the multiple-input-multiple-output transmission channel using a plurality of transmission schemes,
perform a singular value decomposition on the second channel matrix of each transmission scheme to obtain a channel gain of each transmission scheme using a predetermined procedure;
calculate a total channel gain of each transmission scheme to obtain the equivalent single-input single-output channel for the transmission scheme; and
repeat steps (a) to (d) on the plurality of transmission schemes to obtain a plurality of total channel gains;
wherein the first channel gain for each transmission scheme is computed as a product of a minimum value of the first channel gain for each transmission scheme and a signal-to-noise ratio.
12. The system of claim 11 , wherein the link adaptation unit is configured to select a best transmission scheme based on a predetermined condition applied to the plurality of total channel gains.
13. The method of claim 12 , wherein the best transmission scheme is chosen based on a highest value of the equivalent single-input single-output channel for the transmission scheme.
14. The system of claim 11 , wherein the processor is configured to substitute the second channel matrix with a product of a first unitary matrix corresponding to the second channel matrix of each transmission scheme, a diagonal matrix representing the channel gains of the transmission scheme and a second unitary matrix corresponding to the second channel matrix of each transmission scheme.
15. The system of claim 11 , wherein the data stream that has been affected most in the multiple-input multiple-output channel is the minimum value.
16. The system of claim 11 , wherein the processor is configured to add one or more of the channel gain of the transmission scheme, a forward error correction gain of the transmission scheme and a modulation order gain of the transmission scheme to obtain the total channel of the transmission scheme.
17. The system of claim 11 , further comprising at least two transmit antennas coupled to the link adaptation unit.
18. The system of claim 11 , further comprising at least one receive antenna coupled to the link adaptation unit.
19. The system of claim 11 , wherein the link adaptation is optimized based on one or more of a forward error correction gain, a modulation order gain and a space-time coding gain.