概述地面数字电视单频网(Single Frequency Network,SFN)增益的概念、SFN覆盖判据及k因子对数正态法(k Log-Normal Method,k-LNM)算法,研究SFN组网前后对数正态分布变量的变化趋势,将SFN增益分为加性增益和统计增益,针对等场强和不等场...概述地面数字电视单频网(Single Frequency Network,SFN)增益的概念、SFN覆盖判据及k因子对数正态法(k Log-Normal Method,k-LNM)算法,研究SFN组网前后对数正态分布变量的变化趋势,将SFN增益分为加性增益和统计增益,针对等场强和不等场强两种场景给出了应用k-LNM计算SFN增益的实例并分析计算结果。研究过程和结果为地面数字电视广播(Digital Television Terrestrial Multimedia Broadcasting,DTMB)SFN组网规划和建设过程中扩大覆盖和降低干扰提供了新的理论依据。展开更多
The hybrid mobile satellite system operating in a single frequency network (SFN) mode is increasingly becoming attractive. The combination of satellite component (SC) and terrestrial component (TC) promises a be...The hybrid mobile satellite system operating in a single frequency network (SFN) mode is increasingly becoming attractive. The combination of satellite component (SC) and terrestrial component (TC) promises a better quality of service (QoS). Multimedia broadcast and multicast services (MBMS) are expected to be prevailed in this kind of system. Several space frequency (SF) or space time (ST) codes have been proposed to enhance the system performance due to the lack of reverse link and omni-directional transmission. However, they mostly consider the system with only one SC and one TC and fail to make full use of available diversities. This paper presents a novel way to realize the dual polarization multiple input multiple output (MIMO) transmission by using the space time frequency (STF) code. The theoretical analysis and simulations indicate that the application of STF code can improve the system performance dramatically. A higher diversity gain can be achieved due to the cooperative transmission of SC and TC, while the coding gain can be enhanced by the reusing of STF code between SCs or TCs. Even if some of the links are lost, it can still work properly and benefit from the STF code. The relative relay can result in a degradation up to 0.5 dB in the coding gain.展开更多
文摘概述地面数字电视单频网(Single Frequency Network,SFN)增益的概念、SFN覆盖判据及k因子对数正态法(k Log-Normal Method,k-LNM)算法,研究SFN组网前后对数正态分布变量的变化趋势,将SFN增益分为加性增益和统计增益,针对等场强和不等场强两种场景给出了应用k-LNM计算SFN增益的实例并分析计算结果。研究过程和结果为地面数字电视广播(Digital Television Terrestrial Multimedia Broadcasting,DTMB)SFN组网规划和建设过程中扩大覆盖和降低干扰提供了新的理论依据。
基金supported by the Hi-Tech Research and Development Program of China (2012AA01A506-4)
文摘The hybrid mobile satellite system operating in a single frequency network (SFN) mode is increasingly becoming attractive. The combination of satellite component (SC) and terrestrial component (TC) promises a better quality of service (QoS). Multimedia broadcast and multicast services (MBMS) are expected to be prevailed in this kind of system. Several space frequency (SF) or space time (ST) codes have been proposed to enhance the system performance due to the lack of reverse link and omni-directional transmission. However, they mostly consider the system with only one SC and one TC and fail to make full use of available diversities. This paper presents a novel way to realize the dual polarization multiple input multiple output (MIMO) transmission by using the space time frequency (STF) code. The theoretical analysis and simulations indicate that the application of STF code can improve the system performance dramatically. A higher diversity gain can be achieved due to the cooperative transmission of SC and TC, while the coding gain can be enhanced by the reusing of STF code between SCs or TCs. Even if some of the links are lost, it can still work properly and benefit from the STF code. The relative relay can result in a degradation up to 0.5 dB in the coding gain.