为降低OFDM系统中部分传输序列的计算复杂度，提出一种对称双二叉树的相位搜索方法，将最优相位因子的搜索映射为满二叉树中代价最小通路的搜索. 通过选择中间节点数量与二叉树的搜索深度，在有效抑制OFDM峰值平均功率比的同时大幅度降低了计算复杂度. 仿真结果表明，该方法能很好地协调OFDM系统性
能和计算复杂度.
To reduce computation complexity of the partial transmit sequence (PTS) for OFDM systems, a symmetrical dual binary tree search method is proposed, in which the search of the optimum phase factor is mapped to the search of a minimum cost path of a full binary tree. By selecting the number of intermediate
nodes and the search depth, the proposed method effectively reduce both peak-to-average power ratio (PAPR) and the computation complexity of PTS. Simulation results show that the method can make a good tradeoff between the computation complexity and the OFDM performance.
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