Method and apparatus for modulation and coding scheme adaption in a MIMO system
View Patent ↗Method and apparatus for decoding a transmitted signal by a receiver in a MIMO system into a first estimate component for estimating a first signal, a first interference component indicating interference resulting from a correlation relationship among a set of signals to be transmitted, and a first noise component. A base station generates the transmitted signal from the set of signals through a coding process, the coding process defining a correlation relationship amongst the set of signals. The correlation information about the correlation relationship is transmitted to the receiver directly or by a dedicated reference symbol. The decoding is performed by determining a linear receiver filter for the first signal in accordance with the correlation information, and de-correlating the first signal and interferences.
1. A method for signal processing in a communication system, comprising:
receiving, by a receiver, a transmitted signal sent by a transmitter through a channel, the transmitted signal being generated from a set of signals according to a coding process, the set of signals comprising a first signal and a plurality of other signals, the coding process defining a correlation relationship amongst the first signal and the plurality of other signals in the set, and including correlation information relating to the correlation relationship in the transmitted signal; and
decoding, in accordance with the correlation information, the transmitted signal into a first estimate component for estimating the first signal, a first interference component indicating interference resulting from the correlation relationship, and a first noise component indicating impact of the noise on transmission of the first signal.
2. The method of claim 1 , further comprising:
decoding the received signal into a second estimate component for estimating a second signal of the set of signals, a second interference component caused by the correlation relationship among the set of signals, and a second noise component.
3. The method of claim 1 , wherein the transmitter is a base station of a multi-user multiple input, multiple output (MIMO) system, and the receiver is a user equipment within the multi-user MIMO system.
4. The method of claim 1 , wherein the correlation information is received by the receiver from the transmitter using one of a pilot signal, a control signal, or a dedicated reference symbol (DRS).
5. The method of claim 1 , wherein the coding process used in generating the transmitted signal from the set of signals comprises a linear zero-forcing precoding performed by a precoder within the transmitter.
6. The method of claim 1 , wherein the coding process used in generating the transmitted signal from the set of signals comprises a linear regularized zero-forcing precoding performed by a precoder within the transmitter.
7. The method of claim 1 , wherein the coding process used in generating the transmitted signal from the set of signals comprises a dirty-paper non-liner precoding performed by a precoder within the transmitter.
8. The method of claim 1 , wherein the decoding the received signal comprises:
determining a linear receiver filter for the first signal; and
performing a de-correlation of the first signal and interferences to generate the first estimate component for estimating the first signal, the first interference component, and the first noise component.
9. The method of claim 8 , wherein the correlation information is a correlation matrix R x =E[xx H ] or D=diag(R x ) −1 , wherein x=[x 1 x 2 . . . x K ] T is the set of signals.
10. The method of claim 8 , wherein the linear receiver filter for the first signal x j is r 1×N =[R x ] jth row H H (HR x H H +R n ) −1 , wherein x=[x 1 x 2 . . . x K ] T is the set of signals, R x =E[xx H ] is a correlation matrix of x=[x 1 x 2 . . . x K ] T , H represents a combined impact of the channel and the coding process, and the channel H has a noise vector n with a correlation matrix R n =E[nn H ].
11. The method of claim 9 , wherein the linear receiver filter for the first signal x j is s*r 1×N =s*[R x ] jth row H H (HR x H H +R n ) −1 , wherein a scalar number is denoted as s.
12. The method of claim 9 , wherein the first estimate component for the first signal x j is
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13. The method of claim 9 , wherein the first interference component is
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14. The method of claim 9 , wherein a signal to interference and noise ratio (SINR) for the first signal is
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15. The method of claim 8 , wherein the de-correlation of the first signal and the interferences is derived through usage of a Cholesky factorization process.
16. An apparatus for signal processing in a communication system, the apparatus comprising:
a receiver configured to receive a transmitted signal sent by a transmitter through a channel, the transmitted signal being generated from a set of signals according to a coding process, the set of signals comprising a first signal and a plurality of other signals, the coding process defining a correlation relationship amongst the first signal and the plurality of other signals in the set, and including correlation information relating to the correlation relationship in the transmitted signal; and
a processor configured to decode, in accordance with the correlation information, the transmitted signal into a first estimate component for estimating the first signal, a first interference component indicating interference resulting from the correlation relationship, and a first noise component indicating impact of the noise on transmission of the first signal.
17. The apparatus of claim 16 , wherein:
the processor is configured to generate a linear receiver filter for the first signal; and
the processor is configured to de-correlate the first signal and interferences to generate the first estimate component for estimating the first signal, the first interference component, and the first noise component.
18. The apparatus of claim 17 , wherein the linear receiver filter for the first signal x j is s*r 1×N =s*[R x ] jth row H H (HR x H H +R n ) −1 , wherein x=[x 1 x 2 . . . x K ] T is the set of signals, R x =E[xx H ] is a correlation matrix of x=[x 1 x 2 . . . x K ] T , H represents a combined impact of the channel and the coding process, and the channel has a noise vector n with a correlation matrix R n =E[nn H ], a scalar number is denoted as s, the first estimate component for the first
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and a signal to interference and noise ratio (SINR) for the first signal is
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19. The apparatus of claim 16 , wherein the apparatus is an user equipment (UE).
20. An apparatus for signal processing in a communication system, the apparatus comprising:
a receiver configured to receive a transmitted signal sent by a transmitter through a channel, the transmitted signal being generated from a set of signals according to a coding process, the set of signals comprising a first signal and a plurality of other signals, the coding process defining a correlation relationship amongst the first signal and the plurality of other signals in the set, and including a correlation information relating to the correlation relationship in the transmitted signal; and
a processor configured to generate a linear receiver filter for the first signal, and to decode, in accordance with the correlation information, the transmitted signal into a first estimate component for estimating the first signal, a first interference component indicating interference resulting from the correlation relationship, and a first noise component indicating impact of the noise on transmission of the first signal.
21. The apparatus of claim 20 , wherein the linear receiver filter for the first signal x j is s*r 1×N =s*[R x ] jth row H H (HR x H H +R n ) −1 , wherein x=[x 1 x 2 . . . x K ] T is the set of signals, R x =E[xx H ] is a correlation matrix of x=[x 1 x 2 . . . x K ] T , H represents a combined impact of the channel and the coding process, and the channel has a noise vector n with a correlation matrix R n =E[nn H ], a scalar number is denoted as s, the first estimate component for the first
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and a signal to interference and noise ratio (SINR) for the first signal is
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