帧长和信道预测对自适应调制系统性能的影响
Effect of Packet Duration and Channel Prediction on Performance of Adaptive Modulation System
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摘要: 该文主要分析了在自适应调制系统中,帧长自适应和信道预测对系统性能的影响。推导了信道预测和没有信道预测的自适应调制系统的频谱效率公式,分析结果表明对于自适应调制系统,信道预测的系统频谱效率是最优的,非信道预测系统根据信道情况选择最优帧长可以获得该系统的最优系统频谱效率,但它是低于信道预测的频谱效率的,而且是随多普勒频率的增大而逐渐减小的。Abstract: In this paper, the effect of packet duration and channel prediction is analyzed in adaptive modulation. Spectral efficiency equations are derived for both systems with and without channel prediction. Numerical results show that systems with channel prediction can get maximum spectral efficiency while systems without channel prediction but chosen optimum packet length can get suboptimum frequency efficiency, which is inversely proportional to Doppler frequency.
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