TY - JOUR
T1 - Chance-constrained optimization of OFDMA cognitive radio uplinks
AU - Soltani, Nasim Yahya
AU - Kim, Seung Jun
AU - Giannakis, Georgios B
PY - 2013
Y1 - 2013
N2 - A resource allocation task for the uplink of OFDMA-based cognitive radio (CR) systems is considered. The weighted sum-rate is maximized over subcarrier assignment as well as over power loading per CR user, while protecting primary user (PU) systems. However, due to the lack of explicit support from PU systems, the channels from CR users to the PU may not be accurately acquired. Thus, the PU interference constraint is posed as a chance constraint, for which conservative convex approximation is employed for tractability. In particular, to mitigate the combinatorial complexity incurred for optimal subcarrier assignment, a separable structure is pursued, and the dual decomposition method is adopted to obtain near-optimal solutions. Numerical tests verify that the proposed algorithms yield higher weighted sum-rate at lower computational complexity than a benchmark algorithm.
AB - A resource allocation task for the uplink of OFDMA-based cognitive radio (CR) systems is considered. The weighted sum-rate is maximized over subcarrier assignment as well as over power loading per CR user, while protecting primary user (PU) systems. However, due to the lack of explicit support from PU systems, the channels from CR users to the PU may not be accurately acquired. Thus, the PU interference constraint is posed as a chance constraint, for which conservative convex approximation is employed for tractability. In particular, to mitigate the combinatorial complexity incurred for optimal subcarrier assignment, a separable structure is pursued, and the dual decomposition method is adopted to obtain near-optimal solutions. Numerical tests verify that the proposed algorithms yield higher weighted sum-rate at lower computational complexity than a benchmark algorithm.
KW - Cognitive radios
KW - chance-constrained programming
KW - channel uncertainty
KW - orthogonal frequency-division multiple access
KW - resource allocation
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U2 - 10.1109/TWC.2013.011713.120155
DO - 10.1109/TWC.2013.011713.120155
M3 - Article
AN - SCOPUS:84875620476
SN - 1536-1276
VL - 12
SP - 1098
EP - 1107
JO - IEEE Transactions on Wireless Communications
JF - IEEE Transactions on Wireless Communications
IS - 3
M1 - 6416888
ER -