A vertical handoff decision algorithm in heterogeneous networks composed of CDMA Cell Networks (CN) and Wireless Local Area Network (WLAN) is proposed to minimize the total inter- ference in CDMA. The scope of WLAN is...A vertical handoff decision algorithm in heterogeneous networks composed of CDMA Cell Networks (CN) and Wireless Local Area Network (WLAN) is proposed to minimize the total inter- ference in CDMA. The scope of WLAN is determined by minimizing interference and each commu- nicating node shall handoff to WLAN as soon as it enters the scope. We first propose a model for heterogeneous networks, and based on it we obtain the close-form expression of interference. In order to minimize interference, we use simulation annealing method to get the WLAN radius, which is called basic algorithm. In order to reduce the interference further, we improve the basic and get the enhanced algorithm. Through numerical computing, we analyze the interference in condition of different call arrive rates, and results show that the enhanced can reduce interference more greatly than the basic.展开更多
A new scheme based on SOA-MZI for all-optical 2R regeneration is proposed. The characteristics of gain and switching window of this device are investigated in detail. Numerical simulation results indicate that the non...A new scheme based on SOA-MZI for all-optical 2R regeneration is proposed. The characteristics of gain and switching window of this device are investigated in detail. Numerical simulation results indicate that the nonlinear gain compression, the time delay between the input optical signal and the width of the optical pulse are essential parameters for a good performance of all-optical 2R regeneration.展开更多
文摘A vertical handoff decision algorithm in heterogeneous networks composed of CDMA Cell Networks (CN) and Wireless Local Area Network (WLAN) is proposed to minimize the total inter- ference in CDMA. The scope of WLAN is determined by minimizing interference and each commu- nicating node shall handoff to WLAN as soon as it enters the scope. We first propose a model for heterogeneous networks, and based on it we obtain the close-form expression of interference. In order to minimize interference, we use simulation annealing method to get the WLAN radius, which is called basic algorithm. In order to reduce the interference further, we improve the basic and get the enhanced algorithm. Through numerical computing, we analyze the interference in condition of different call arrive rates, and results show that the enhanced can reduce interference more greatly than the basic.
文摘A new scheme based on SOA-MZI for all-optical 2R regeneration is proposed. The characteristics of gain and switching window of this device are investigated in detail. Numerical simulation results indicate that the nonlinear gain compression, the time delay between the input optical signal and the width of the optical pulse are essential parameters for a good performance of all-optical 2R regeneration.