On Resource Management in OFDMA Based Wireless Networks

• Main Authors: Lin, Yuan-Bin, 林淵斌
• Other Authors: Su, Yu-Ted
• Format: Others
• Language: en_US
• Published: 2009
• Online Access: http://ndltd.ncl.edu.tw/handle/14215950667421520876

博士 === 國立交通大學 === 電信工程系所 === 97 === Algorithms for finding suboptimal and optimal solutions to total power minimization or capacity maximization resource allocation problems in OFDMA-based networks haven been studied by many authors. But the complexities of finding the optimal solution and some suboptimal are prohibitively high and only few numerical examples for low dimension cases can be found. On the other hand, low-complexity suboptimal solutions often give unsatisfactory performance. In this thesis, we propose optimal and suboptimal resource allocation solutions for OFDMA and MIMO-OFDMA wireless networks. Various design criteria and system constraints are considered. The corresponding complexities for all suboptimal solutions are relatively low while that for the optimal algorithm is only moderate high. We first investigate the problem of transmit power minimization in an OFDMA downlink network subject to user rates and BER requirements constraints. We provide near-optimal and optimal solutions based on the dynamic programming and branch&bound methodologies. The second scenario we consider is a weighted sum rate maximization problem which is solved via dynamic programming and dual decomposition. We then proceed to consider the product rate maximization scenario and present a suboptimal solution. Finally, we consider a total power minimization problem for a MIMO-OFDMA wireless networks and present a low-complexity solution. The main concept in our proposed algorithms can be easily applied to obtain a near-optimal solution for many similar multi-constraints optimization problem with low complexity.