MAKING FULL USE OF OUTDATED CHANNEL ESTIMATES FOR BLOCK BY BLOCK ADAPTIVE MODULATIONS

作     者：Shan Xiaohong Bi Guangguo 

作者机构：National Mobile Commun. Research Lab Southeast Univ. Nanjing 210005 China 

出 版 物：《Journal of Electronics(China)》 (电子科学学刊（英文版）)

年 卷 期：2007年第24卷第1期

页      面：54-59页

学科分类：11[军事学] 0810[工学-信息与通信工程] 1105[军事学-军队指挥学] 08[工学] 081002[工学-信号与信息处理] 110503[军事学-军事通信学] 

基　　金：Supported by the National Natural Science Foundation of China (No.60496311) 

主　　题：Adaptive modulation Block by block adaptation Channel estimation Spectral efficiency 

摘      要：This paper explores the potential to use accurate but outdated channel estimates for adaptive modulation. The work is novel in that the research is conditioned on block by block adaptation. First,we define a new quantity,the Tolerable Average Use Delay (TAUD),which can indicate the ability of an adaptation scheme to tolerate the delay of channel estimation results. We find that for the variable-power schemes,TAUD is a constant and dependent on the target Bit Error Rate (BER),average power and Doppler frequency; while for the constant-power schemes,it depends on the ad-aptation block length as well. At last,we investigate the relation between the delay tolerating per-formance and the spectral efficiency and give the system design criterion. The delay tolerating per-formance is improved at the price of lower data rate.