基于OFDM的认知无线电系统中的一种改进的功率分配算法的研究

摘要

The iterative partitioned water-filling algorithm is improved applying in the power allocation in the OFDM-based cognitive radio systems that aimed at maximizing the capacity of the systems with the consideration of the total power constraint and each subchannel power constraints. The power leakage of the adjacent subcarriers is especially considered when the power constraints of the PU s are very strict, and set the protection band between the PU s' spectrum and the SU s' spectrum and made power allocation of the other subcarriers form the ladder shape, only performing die iterative partitioned water-filling algorithm in the subchannels whose power constraints were strict. The simulation result shows that the improved power allocation algorithm is not only close to the iterative partitioned water-filling algorithm, but also has low complexity.%改进了应用于基于OFDM的认知无线电系统中的功率分配算法.迭代分块注水算法,目标是在总的功率约束和每个子信道的功率约束的条件下最大化系统的容量.在主用户的功率约束非常严格时,尤其考虑了相邻子载波的功率泄露,并且在主用户的频谱和认知用户的频谱之间设置保护带,使其他子载波的功率分配呈现梯形分布.所以只是在功率约束比较严格的子载波上实施迭代分块注水算法.仿真结果表明,改进的功率分配算法性能接近迭代分块注水算法,而且具有较低的复杂性.