The rate-based feedback PD-P controller of two freedom-degrees is proposed for the congestion control in computer networks to improve the abilities against disturbance. Moreover, the Dahlin algorithm is used for setti...The rate-based feedback PD-P controller of two freedom-degrees is proposed for the congestion control in computer networks to improve the abilities against disturbance. Moreover, the Dahlin algorithm is used for setting the controller to overcome the adverse effect caused by the propagation delay effectively. The research results show that the proposed scheme not only can make sources respond to the changes of network state more quickly, but also has a good robustness against estimated error of the delay. Then the packet queue level in buffer will be stabilized on the set-point quickly, and the delay and its jitter of the packet queuing will also become smaller. Besides, the flexible bandwidth allotment can be obtained by setting the weight coefficients.展开更多
本文针对双层异构网络,提出一种利用当前和过期发射端信道状态信息(Channel State Information at the Transmitters,CSIT)的异构空时干扰对齐(Heterogeneous Space-Time Interference Alignment,HSTIA)方案.该方案将空时干扰对齐拓展...本文针对双层异构网络,提出一种利用当前和过期发射端信道状态信息(Channel State Information at the Transmitters,CSIT)的异构空时干扰对齐(Heterogeneous Space-Time Interference Alignment,HSTIA)方案.该方案将空时干扰对齐拓展至双层异构网络MISO(Multiple Input Single Output)混合信道,研究可达自由度关于CSI(Channel State Information)反馈时延的折中域.结果表明,增加发射端天线数能有效提高可达自由度.基于该结论,将空时干扰对齐技术扩展至双层异构网络MIMO(Multiple Input Multiple Output)混合信道,分析MIMO系统发射端与接收端天线数比对系统自由度的影响,并进一步研究系统达到该自由度时CSI反馈时延的取值范围.结果表明,当发射端与接收端天线数比足够多时,系统自由度的稳健性随接收端天线数的增加而加强.通过仿真分析验证,HSTIA方案利用本地当前和过期CSIT执行发射预编码,实现不同时隙的干扰信号相互消除,从而获得自由度增益,以提高系统的可达速率.展开更多
文摘The rate-based feedback PD-P controller of two freedom-degrees is proposed for the congestion control in computer networks to improve the abilities against disturbance. Moreover, the Dahlin algorithm is used for setting the controller to overcome the adverse effect caused by the propagation delay effectively. The research results show that the proposed scheme not only can make sources respond to the changes of network state more quickly, but also has a good robustness against estimated error of the delay. Then the packet queue level in buffer will be stabilized on the set-point quickly, and the delay and its jitter of the packet queuing will also become smaller. Besides, the flexible bandwidth allotment can be obtained by setting the weight coefficients.
文摘本文针对双层异构网络,提出一种利用当前和过期发射端信道状态信息(Channel State Information at the Transmitters,CSIT)的异构空时干扰对齐(Heterogeneous Space-Time Interference Alignment,HSTIA)方案.该方案将空时干扰对齐拓展至双层异构网络MISO(Multiple Input Single Output)混合信道,研究可达自由度关于CSI(Channel State Information)反馈时延的折中域.结果表明,增加发射端天线数能有效提高可达自由度.基于该结论,将空时干扰对齐技术扩展至双层异构网络MIMO(Multiple Input Multiple Output)混合信道,分析MIMO系统发射端与接收端天线数比对系统自由度的影响,并进一步研究系统达到该自由度时CSI反馈时延的取值范围.结果表明,当发射端与接收端天线数比足够多时,系统自由度的稳健性随接收端天线数的增加而加强.通过仿真分析验证,HSTIA方案利用本地当前和过期CSIT执行发射预编码,实现不同时隙的干扰信号相互消除,从而获得自由度增益,以提高系统的可达速率.
