In this paper, we propose two joint transmit-receive iterative algorithms without the cooperation between different base stations based on the idea of interference alignment (IA) to improve the throughput of relay bac...In this paper, we propose two joint transmit-receive iterative algorithms without the cooperation between different base stations based on the idea of interference alignment (IA) to improve the throughput of relay backhaul links in cellular networks for the case of imperfect channel knowledge,which can be implemented with small changes to existing TD-LTE standards. Unlike the previous interference alignment algorithms' only reducing the sum interference to the other receivers at the transmitter or the sum received Multi-user interference (MUI) at the receiver, our algorithm shapes the transmission of each data stream at transmitters in order not only to minimize interference to the other users, but also to minimize the interference between different streams objected to the same user, suppressing the MUI and Multi-stream interference (MSI) at receivers. The proposed algorithm I is to maximize the SINR at receivers. But the complexity is relatively high. Algorithm II only needs linear operations and sacrifices a little performance for much lower complexity compared to the Maximize SINR iterative algorithm which needs the inversion operation of matrix. It is also proved that the algorithm converges monotonically. The simulation results show that the techniques have considerable performance gain compared with the previous algorithms. Further research about power allocation is also discussed.展开更多
基金Sponsored by the Important National Science & Technology Specific Projects of China (Grant No. 2009ZX03004-001)the Cooperation Project with Huawei Technologies Company (Grant No. YBWL2010242)
文摘In this paper, we propose two joint transmit-receive iterative algorithms without the cooperation between different base stations based on the idea of interference alignment (IA) to improve the throughput of relay backhaul links in cellular networks for the case of imperfect channel knowledge,which can be implemented with small changes to existing TD-LTE standards. Unlike the previous interference alignment algorithms' only reducing the sum interference to the other receivers at the transmitter or the sum received Multi-user interference (MUI) at the receiver, our algorithm shapes the transmission of each data stream at transmitters in order not only to minimize interference to the other users, but also to minimize the interference between different streams objected to the same user, suppressing the MUI and Multi-stream interference (MSI) at receivers. The proposed algorithm I is to maximize the SINR at receivers. But the complexity is relatively high. Algorithm II only needs linear operations and sacrifices a little performance for much lower complexity compared to the Maximize SINR iterative algorithm which needs the inversion operation of matrix. It is also proved that the algorithm converges monotonically. The simulation results show that the techniques have considerable performance gain compared with the previous algorithms. Further research about power allocation is also discussed.
文摘目的设计并筛选针对大鼠Smad3基因的siRNA,构建靶向Smad3基因的shRNA重组慢病毒。方法针对大鼠Smad3基因设计并合成6对siRNA(siRNA001～006)及1对无关对照siRNA,转染大鼠肝细胞株BRL-3A,应用Western Blot检测各siRNA对SMAD3蛋白表达的抑制作用,挑选抑制效率高的siRNA。依据所得的序列合成并克隆到pLL3.7载体中,与包装质粒pRSV-rev、pMDLg-pRRE和VSV-G共转染293FT细胞获得靶向Smad3的慢病毒。通过流式细胞仪绿色荧光蛋白(GFP)荧光计数来检测病毒滴度。结果 Western Blot检测证实siRNA001、siRNA005、siRNA006对SMAD3蛋白表达的抑制作用明显,抑制率分别可达83.36%、86.99%及64.88%,而对照siRNA无明显作用。酶切和测序结果显示Smad3 shRNA及对照shRNA重组载体质粒pLL3.7-shRNA构建成功,将构建的质粒进行慢病毒包装可产生有感染活性的慢病毒颗粒。结论筛选出针对大鼠Smad3基因有明显抑制作用的3对siRNA,并成功构建表达相应shRNA的4种重组慢病毒,为研究调控Smad3的表达对肝再生或肝纤维化的影响提供了实验条件。
