深圳作为我国的经济特区、全国性经济中心城市和国际化城市,正在进行产业结构优化调整,电网负荷特性也在随之变化。结合深圳电网实际情况,对全网各10 k V馈线的负荷分类情况、分类负荷大小进行了调查和统计。并结合2012年夏大方式下电...深圳作为我国的经济特区、全国性经济中心城市和国际化城市,正在进行产业结构优化调整,电网负荷特性也在随之变化。结合深圳电网实际情况,对全网各10 k V馈线的负荷分类情况、分类负荷大小进行了调查和统计。并结合2012年夏大方式下电网拓扑结构,运用容量加权平均方法,最终确定网内各220 k V变电站110 k V侧的负荷构成特性。最后通过归纳分析,确定深圳电网分类负荷的基本特性。展开更多
This paper investigates the secrecy performance of maximal ratio combining （MRC） and selection combining （SC） with imperfect channel state information （CSI） in the physical layer. In a single-input multiple- out...This paper investigates the secrecy performance of maximal ratio combining （MRC） and selection combining （SC） with imperfect channel state information （CSI） in the physical layer. In a single-input multiple- output （SIMO） wiretap channel, a source transmits confidential messages to the destination equipped with M antennas using the MRC/SC scheme to process the received multiple signals. An eavesdropper equipped with N antennas also adopts the MRC/SC scheme to promote successful eavesdropping. We derive the exact and asymptotic closed-form expressions for the ergodic secrecy capacity （ESC） in two cases： （1） MRC with weighting errors, and （2） SC with outdated CSI. Moreover, two important indicators, namely high signal-to-noise ratio （SNR） slope and high SNR power offset, which govern ESC at the high SNR region, are derived. Finally, simulations are conducted to validate the accuracy of our proposed analytical models. Results indicate that ESC rises with the increase of the number of antennas and the received SNR at the destination, and fades with the increase of those at the eavesdropper. Another finding is that the high SNR slope is constant, while the high SNR power offset is correlated with the number of antennas at both the destination and the eavesdropper.展开更多
文摘深圳作为我国的经济特区、全国性经济中心城市和国际化城市,正在进行产业结构优化调整,电网负荷特性也在随之变化。结合深圳电网实际情况,对全网各10 k V馈线的负荷分类情况、分类负荷大小进行了调查和统计。并结合2012年夏大方式下电网拓扑结构,运用容量加权平均方法,最终确定网内各220 k V变电站110 k V侧的负荷构成特性。最后通过归纳分析,确定深圳电网分类负荷的基本特性。
基金Project supported by the National Natural Science Foundation of China （No. 61401372） and the Fundamental Research Funds for the Central Universities, China （Nos. XDJK2015B023 and XDJK2016A011）
文摘This paper investigates the secrecy performance of maximal ratio combining （MRC） and selection combining （SC） with imperfect channel state information （CSI） in the physical layer. In a single-input multiple- output （SIMO） wiretap channel, a source transmits confidential messages to the destination equipped with M antennas using the MRC/SC scheme to process the received multiple signals. An eavesdropper equipped with N antennas also adopts the MRC/SC scheme to promote successful eavesdropping. We derive the exact and asymptotic closed-form expressions for the ergodic secrecy capacity （ESC） in two cases： （1） MRC with weighting errors, and （2） SC with outdated CSI. Moreover, two important indicators, namely high signal-to-noise ratio （SNR） slope and high SNR power offset, which govern ESC at the high SNR region, are derived. Finally, simulations are conducted to validate the accuracy of our proposed analytical models. Results indicate that ESC rises with the increase of the number of antennas and the received SNR at the destination, and fades with the increase of those at the eavesdropper. Another finding is that the high SNR slope is constant, while the high SNR power offset is correlated with the number of antennas at both the destination and the eavesdropper.
