TY - JOUR

T1 - Cooperative transmission for relay networks based on second-order statistics of channel state information

AU - Li, Jiangyuan

AU - Petropulu, Athina P.

AU - Poor, H. Vincent

N1 - Funding Information:
Manuscript received May 19, 2010; revised September 16, 2010; accepted November 02, 2010. Date of publication November 22, 2010; date of current version February 09, 2011. The associate editor coordinating the review of this paper and approving it for publication was Dr. Philippe Ciblat. This research was supported in part by the Office of Naval Research under Grants N-0001-07-10500 and N-00014-09-1-0342, and in part by the National Science Foundation under Grants CNS-09-05425 and CNS-09-05398.

PY - 2011/3

Y1 - 2011/3

N2 - Cooperative transmission in relay networks is considered, in which a source transmits to its destination with the help of a set of cooperating nodes. The source first transmits locally. The cooperating nodes that receive the source signal retransmit a weighted version of it in an amplify-and-forward (AF) fashion. Assuming knowledge of the second-order statistics of the channel state information, beamforming weights are determined so that the signal-to-noise ratio (SNR) at the destination is maximized subject to two different power constraints, i.e., a total (source and relay) power constraint, and individual relay power constraints. For the former constraint, the original problem is transformed into a problem of one variable, which can be solved via Newton's method. For the latter constraint, this problem is solved completely. It is shown that the semidefinite programming (SDP) relaxation of the original problem always has a rank one solution, and hence the original problem is equivalent to finding the rank one solution of the SDP problem. An explicit construction of such a rank one solution is also provided. Numerical results are presented to illustrate the proposed theoretical findings.

AB - Cooperative transmission in relay networks is considered, in which a source transmits to its destination with the help of a set of cooperating nodes. The source first transmits locally. The cooperating nodes that receive the source signal retransmit a weighted version of it in an amplify-and-forward (AF) fashion. Assuming knowledge of the second-order statistics of the channel state information, beamforming weights are determined so that the signal-to-noise ratio (SNR) at the destination is maximized subject to two different power constraints, i.e., a total (source and relay) power constraint, and individual relay power constraints. For the former constraint, the original problem is transformed into a problem of one variable, which can be solved via Newton's method. For the latter constraint, this problem is solved completely. It is shown that the semidefinite programming (SDP) relaxation of the original problem always has a rank one solution, and hence the original problem is equivalent to finding the rank one solution of the SDP problem. An explicit construction of such a rank one solution is also provided. Numerical results are presented to illustrate the proposed theoretical findings.

KW - Channel uncertainty

KW - Semidefinite programming

KW - cooperative communications

KW - relay networks

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U2 - 10.1109/TSP.2010.2094614

DO - 10.1109/TSP.2010.2094614

M3 - Article

AN - SCOPUS:79951644463

VL - 59

SP - 1280

EP - 1291

JO - IRE Transactions on Audio

JF - IRE Transactions on Audio

SN - 1053-587X

IS - 3

M1 - 5643179

ER -