MIMO TRANSMISSION WITH RANK-DEPENDENT PRECODING
First Claim
1. An apparatus for wireless communication, comprising:
- at least one processor configured to obtain a precoding vector for a rank-1 transmission from a first set comprising at least one column vector of a unitary matrix, to perform precoding for the rank-1 transmission based on the precoding vector, to obtain a precoding matrix for a rank-2 transmission from a second set comprising an identity matrix, and to perform precoding for the rank-2 transmission based on the precoding matrix; and
a memory coupled to the at least one processor.
1 Assignment
0 Petitions
Accused Products
Abstract
Techniques for performing rank-dependent precoding for a MIMO transmission are described. Each rank may be associated with a set of at least one precoding vector or matrix that can provide good performance for that rank. A transmitter may obtain a precoding vector for a rank-1 transmission from a first set containing at least one column vector of a unitary matrix, e.g., a Fourier matrix. The transmitter may perform precoding for the rank-1 transmission based on the precoding vector. The transmitter may obtain a precoding matrix for a rank-2 transmission from a second set containing an identity matrix. The transmitter may perform precoding for the rank-2 transmission based on the precoding matrix. For the rank-2 transmission, the transmitter may select the identity matrix as the precoding matrix if a MIMO channel resembles a diagonal channel (which may be determined based on antenna configurations) and may select the unitary matrix otherwise.
90 Citations
34 Claims
-
1. An apparatus for wireless communication, comprising:
-
at least one processor configured to obtain a precoding vector for a rank-1 transmission from a first set comprising at least one column vector of a unitary matrix, to perform precoding for the rank-1 transmission based on the precoding vector, to obtain a precoding matrix for a rank-2 transmission from a second set comprising an identity matrix, and to perform precoding for the rank-2 transmission based on the precoding matrix; and a memory coupled to the at least one processor. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10)
-
-
11. A method for wireless communication, comprising:
-
obtaining a precoding vector for a rank-1 transmission from a first set comprising at least one column vector of a unitary matrix; performing precoding for the rank-1 transmission based on the precoding vector; obtaining a precoding matrix for a rank-2 transmission from a second set comprising an identity matrix; and performing precoding for the rank-2 transmission based on the precoding matrix. - View Dependent Claims (12, 13, 14)
-
-
15. An apparatus for wireless communication, comprising:
-
means for obtaining a precoding vector for a rank-1 transmission from a first set comprising at least one column vector of a unitary matrix; means for performing precoding for the rank-1 transmission based on the precoding vector; means for obtaining a precoding matrix for a rank-2 transmission from a second set comprising an identity matrix; and means for performing precoding for the rank-2 transmission based on the precoding matrix. - View Dependent Claims (16, 17, 18)
-
-
19. A machine-readable medium comprising instructions which, when executed by a machine, cause the machine to perform operations including:
-
obtaining a precoding vector for a rank-1 transmission from a first set comprising at least one column vector of a unitary matrix; performing precoding for the rank-1 transmission based on the precoding vector; obtaining a precoding matrix for a rank-2 transmission from a second set comprising an identity matrix; and performing precoding for the rank-2 transmission based on the precoding matrix. - View Dependent Claims (20, 21, 22)
-
-
23. An apparatus for wireless communication, comprising:
-
at least one processor configured to receive a rank-1 transmission sent from multiple transmit antennas with a precoding vector selected from a first set comprising at least one column vector of a unitary matrix, to process the rank-1 transmission to recover a data stream sent in the rank-1 transmission, to receive a rank-2 transmission sent from the multiple transmit antennas with a precoding matrix selected from a second set comprising an identity matrix, and to process the rank-2 transmission to recover two data streams sent in the rank-2 transmission; and a memory coupled to the at least one processor. - View Dependent Claims (24, 25, 26, 27, 28)
-
-
29. A method for wireless communication, comprising:
-
receiving a rank-1 transmission sent from multiple transmit antennas with a precoding vector selected from a first set comprising at least one column vector of a unitary matrix; processing the rank-1 transmission to recover a data stream sent in the rank-1 transmission; receiving a rank-2 transmission sent from the multiple transmit antennas with a precoding matrix selected from a second set comprising an identity matrix; and processing the rank-2 transmission to recover two data streams sent in the rank-2 transmission. - View Dependent Claims (30, 31)
-
-
32. An apparatus for wireless communication, comprising:
-
means for receiving a rank-1 transmission sent from multiple transmit antennas with a precoding vector selected from a first set comprising at least one column vector of a unitary matrix; means for processing the rank-1 transmission to recover a data stream sent in the rank-1 transmission; means for receiving a rank-2 transmission sent from the multiple transmit antennas with a precoding matrix selected from a second set comprising an identity matrix; and means for processing the rank-2 transmission to recover two data streams sent in the rank-2 transmission. - View Dependent Claims (33, 34)
-
Specification