In Multiple-Input Multiple-Out (MIMO) systems, the user selection algorithm plays an important role in the realization of multiplexing gain. In this paper, an improved Semi-orthogonal User Selection algorithm based ...In Multiple-Input Multiple-Out (MIMO) systems, the user selection algorithm plays an important role in the realization of multiplexing gain. In this paper, an improved Semi-orthogonal User Selection algorithm based on condition number is proposed. Besides, a new MIMO pre- coding scheme is designed. The proposed SUS- CN (SUS with condition number) algorithm outperforms the SUS algorithm for the selection of users with better matrix inversion property, thus a higher information rate for selected user pair is achieved. The designed MIMO precoding matrix brings benefits of the power equality at transmitted terminals, the limited dynamic range of the power over time, and a better power efficiency. The simulation results give the key insights into the im- pact of the different condition number value and users on the sum-rate capacity.展开更多
The study of security in computer networks is a key issue, which is a rapidlygrowing area of interest because of its importance. Main network security problems are analyzed inthis paper above all, which currently are ...The study of security in computer networks is a key issue, which is a rapidlygrowing area of interest because of its importance. Main network security problems are analyzed inthis paper above all, which currently are confronted with network systems and existing works inintrusion detection. And then an intrusion detection system model based on Immune Principle (IPIDS)is presented. Meanwhile, it expatiates detailed implementation of the methods how to reduce the highfalse positive and negative alarms of the traditional Intrusion Detection System (IDS). At last asimple simulation is performed on this model just using string match algorithm as binding mechanism.The simulation results indicate that the model can detect malicious activity effectively, andconsequently the security and steadiness of the whole network system are improved also.展开更多
基金This paper was supported by the National Natural Science Foundation of China under Grant No.61390513 and 61201225,and National Science and Technology Major Project of China under Grant No.2013ZX03003004,the Natural Science Foundation of Shanghai under Grant No.12ZR1450800,and sponsored by Shanghai Pujiang Program under Grant No.13PJD030.It was also supported by the Fundamental Research Funds for the Central Universities under Grant No.20140767,the Program for Young Excellent Talents in Tongji University under Grant No.2013KJ007,and 'Chen Guang' project supported by Shanghai Municipal Education Commission and Shanghai Education Development Foundation under Grant No.13CG18
文摘In Multiple-Input Multiple-Out (MIMO) systems, the user selection algorithm plays an important role in the realization of multiplexing gain. In this paper, an improved Semi-orthogonal User Selection algorithm based on condition number is proposed. Besides, a new MIMO pre- coding scheme is designed. The proposed SUS- CN (SUS with condition number) algorithm outperforms the SUS algorithm for the selection of users with better matrix inversion property, thus a higher information rate for selected user pair is achieved. The designed MIMO precoding matrix brings benefits of the power equality at transmitted terminals, the limited dynamic range of the power over time, and a better power efficiency. The simulation results give the key insights into the im- pact of the different condition number value and users on the sum-rate capacity.
基金This work is sponsored by the National Natural Science Foundation of P. R. China (No.60173037 &70271050) National 863 High Technology Research Program ofP. R. China (No.2004AA775053) the Natural Science Foundation of Jiangsu Province (No.BK20031
文摘The study of security in computer networks is a key issue, which is a rapidlygrowing area of interest because of its importance. Main network security problems are analyzed inthis paper above all, which currently are confronted with network systems and existing works inintrusion detection. And then an intrusion detection system model based on Immune Principle (IPIDS)is presented. Meanwhile, it expatiates detailed implementation of the methods how to reduce the highfalse positive and negative alarms of the traditional Intrusion Detection System (IDS). At last asimple simulation is performed on this model just using string match algorithm as binding mechanism.The simulation results indicate that the model can detect malicious activity effectively, andconsequently the security and steadiness of the whole network system are improved also.