美军新一代短波通信3G-ALE信号与上一代2G-ALE信号相比,在通信链路层采用了多重数据编码方式,极大提高了链路层协议信息传输可靠性。针对3G-ALE信号从协议信息到有效载荷数据的链路层数据编码展开研究,分析了编码原理与编码性能。首先,...美军新一代短波通信3G-ALE信号与上一代2G-ALE信号相比,在通信链路层采用了多重数据编码方式,极大提高了链路层协议信息传输可靠性。针对3G-ALE信号从协议信息到有效载荷数据的链路层数据编码展开研究,分析了编码原理与编码性能。首先,分析信号的数据结构特征与数据编码流程;其次,依次从卷积编码、交织编码、Walsh正交扩频与伪随机加扰等四个编码操作,具体分析数据编码提高协议信息传输可靠性的机理;最后,仿真实现数据编码结果与协议信息传输性能。仿真结果表明,3G-ALE信号经过链路层数据编码,通信接收端能够获得15 d B左右的处理增益,有效提高了协议信息传输可靠性,使得非合作的通信对抗面临巨大困难。展开更多
The quantitative structure-activity relationship （QSAR） of 16 pyrazole compounds was studied by ab initio method at the HF/3-21G level using Guassian03 soft. The optimized structures together with some characteristi...The quantitative structure-activity relationship （QSAR） of 16 pyrazole compounds was studied by ab initio method at the HF/3-21G level using Guassian03 soft. The optimized structures together with some characteristic and electric parameters of the title compounds were obtained; some stereo-parameters were calculated by HyperChem software. Stepwise multiple regression method was adopted to establish bi- and tri-parametric models between biological activity and some parameters. The lager △E and logP, the higher biological activity; and the biological activity would be promoted with the smaller μ, QN and QPYRA. It provided a theory direction to synthesize some compounds with high activity.展开更多
文摘美军新一代短波通信3G-ALE信号与上一代2G-ALE信号相比,在通信链路层采用了多重数据编码方式,极大提高了链路层协议信息传输可靠性。针对3G-ALE信号从协议信息到有效载荷数据的链路层数据编码展开研究,分析了编码原理与编码性能。首先,分析信号的数据结构特征与数据编码流程;其次,依次从卷积编码、交织编码、Walsh正交扩频与伪随机加扰等四个编码操作,具体分析数据编码提高协议信息传输可靠性的机理;最后,仿真实现数据编码结果与协议信息传输性能。仿真结果表明,3G-ALE信号经过链路层数据编码,通信接收端能够获得15 d B左右的处理增益,有效提高了协议信息传输可靠性,使得非合作的通信对抗面临巨大困难。
基金talents in University (NCET-04-0649)the Natural Science Foundation of Shandong Province (Y2006B07, Z2006B01)
文摘The quantitative structure-activity relationship （QSAR） of 16 pyrazole compounds was studied by ab initio method at the HF/3-21G level using Guassian03 soft. The optimized structures together with some characteristic and electric parameters of the title compounds were obtained; some stereo-parameters were calculated by HyperChem software. Stepwise multiple regression method was adopted to establish bi- and tri-parametric models between biological activity and some parameters. The lager △E and logP, the higher biological activity; and the biological activity would be promoted with the smaller μ, QN and QPYRA. It provided a theory direction to synthesize some compounds with high activity.
