1. Optimum power control for transmitter cooperation in OFDMA based wireless networks
- Author
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Sezi Bakim, Onur Kaya, Işık Üniversitesi, Mühendislik Fakültesi, Elektrik-Elektronik Mühendisliği Bölümü, Işık University, Faculty of Engineering, Department of Electrical-Electronics Engineering, Bakım, İsmail Sezi, and Kaya, Onur
- Subjects
Transmitter cooperation ,Orthogonal frequency-division multiplexing ,Computer science ,Iterative methods ,Cooperative OFDMA system ,Orthogonal frequency-division multiple access ,Decoding ,OFDM modulation ,Optimal power distribution ,Fading channels ,Subgradient algorithm ,Radio transmitters ,Subcarrier ,Block Markov superposition encoding ,Telecommunications link ,Wireless networks ,Cooperative communication ,Channel code ,Wireless network ,Resource management ,Markov processes ,Transmitter ,Rate region boundary ,Full channel state information ,Vectors ,Channel coding ,Block codes ,Frequency division multiple access ,Optimal control ,Power control ,Decoding methods ,Uplink ,Block code ,Mathematical optimization ,Optimum power control ,Inter-subchannel cooperative encoding ,Data_CODINGANDINFORMATIONTHEORY ,Radio networks ,Fading ,Computer Science::Information Theory ,Optimal power allocation policy ,Frequency-division multiple access ,Resource-allocation ,Telecommunication control ,Systems ,Cooperative orthogonal frequency division multiple access system ,Transmitters ,Iterative waterfilling-like algorithm ,Channel state information ,Encoding - Abstract
For a cooperative orthogonal frequency division multiple access (OFDMA) system with two transmitters (TXs), and full channel state information (CSI), we obtain the optimal power allocation (PA) policies which maximize the rate region achievable by a recently introduced version of block Markov superposition encoding (BMSE): inter-subchannel cooperative encoding (ISCE) [1]. We provide the optimality conditions that need to be satisfied by the powers associated with the transmitted codewords. We propose two algorithms that yield the optimal power distribution: a subgradient algorithm which achieves an arbitrary rate point on the achievable rate region boundary, and an iterative waterfilling-like algorithm which maximizes the sum rate, and converges much faster. We observe that, utilization of power control to take advantage of the diversity offered by the cooperative OFDMA system, not only leads to a remarkable improvement in achievable rates, but also may help determine how the subchannels have to be instantaneously allocated to various tasks in cooperation. Publisher's Version
- Published
- 2011