[1]单晓红,毕光国.滚降系数对自适应QAM的抗时延扩展性能和频谱效率的影响[J].东南大学学报(自然科学版),2007,37(3):359-363.[doi:10.3969/j.issn.1001-0505.2007.03.001]
 Shan Xiaohong,Bi Guangguo.Effects of rolloff factor on resistance to time delay spread and spectral efficiency of adaptive QAM[J].Journal of Southeast University (Natural Science Edition),2007,37(3):359-363.[doi:10.3969/j.issn.1001-0505.2007.03.001]
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滚降系数对自适应QAM的抗时延扩展性能和频谱效率的影响()
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《东南大学学报(自然科学版)》[ISSN:1001-0505/CN:32-1178/N]

卷:
37
期数:
2007年第3期
页码:
359-363
栏目:
信息与通信工程
出版日期:
2007-05-20

文章信息/Info

Title:
Effects of rolloff factor on resistance to time delay spread and spectral efficiency of adaptive QAM
作者:
单晓红 毕光国
东南大学移动通信国家重点实验室,南京 210096
Author(s):
Shan Xiaohong Bi Guangguo
National Mobile Communications Research Laboratory, Southeast University, Nanjing 210096, China
关键词:
自适应正交幅度调制 滚降系数 多径时延扩展 频谱效率
Keywords:
adaptive quadrature amplitude modulation(AQAM) rolloff factor multipath time delay spread spectral efficiency
分类号:
TN929.5
DOI:
10.3969/j.issn.1001-0505.2007.03.001
摘要:
在多径衰落信道中研究了自适应正交幅度调制(AQAM)的抗时延扩展性能和频谱效率,系统的接收-发送合成滤波器具有升余弦频谱.在平均误比特率受限的情况下,分析了平均bits-per-symbol和平均误比特率与归一化rms时延扩展(rms时延扩展与符号周期之比)的关系.计算结果显示:当滚降系数增大时,AQAM所能应对的最大归一化rms时延扩展也随之增大,由此证明AQAM的抗时延扩展性能随滚降系数的增大而改善.平均频谱效率可视为3个参数的函数,即滚降系数、归一化rms时延扩展及发送信号能量与噪声之比.分析结果表明,当滚降系数增大时,平均频谱效率的变化是不确定的,具体情况取决于另外2个参数.
Abstract:
The resistance to time delay spread and spectral efficiency of adaptive quadrature amplitude modulation(AQAM)are investigated over multipath fading channels. The joint frequency response of the transmitting and receiving filters has the raised-cosine spectrum. The effects of normalized rms delay spread(ratio of rms delay spread to symbol period)on the average bits-per-symbol and average BER are analyzed under the average BER constraint. Data results show that AQAM can tolerate greater normalized rms delay spread when the rolloff factor increases, which affirms the notion that delay spread immunity improves with the rolloff factor rising. The average spectral efficiency is studied as a function of the rolloff factor, normalized rms delay spread, and signal-to-noise ratio. It is observed that when the rolloff factor increases, reaction of the average spectral efficiency is indefinite and depends on the other two parameters.

参考文献/References:

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备注/Memo

备注/Memo:
基金项目: 国家自然科学重大基金资助项目(60496311).
作者简介: 单晓红(1976—),女,博士生; 毕光国(联系人),男,教授,博士生导师,bigg@seu.edu.cn.
更新日期/Last Update: 2007-05-20