作者机构：
[Huang, Li; Li, Mengxing; Gong, Lunfeng] Hunan City Univ, Dept Phys & Telecommun, Yiyang 413000, Hunan, Peoples R China.
通讯机构：
[Li, Mengxing] H;Hunan City Univ, Dept Phys & Telecommun, Yiyang 413000, Hunan, Peoples R China.
会议名称：
International Conference on Advanced in Control Engineering and Information Science (CEIS)
会议时间：
AUG 18-19, 2011
会议地点：
Dali, PEOPLES R CHINA
会议主办单位：
[Li, Mengxing;Huang, Li;Gong, Lunfeng] Hunan City Univ, Dept Phys & Telecommun, Yiyang 413000, Hunan, Peoples R China.
会议论文集名称：
Procedia Engineering
关键词：
Call center;Dynamic link library;Intelligent scheduling;Neural network;Particle swarm optimization
摘要：
The main problems of the design of large-scale call center intelligent scheduling system were given firstly; we proposed and testified that using four BP Neural Network models separately in different time buckets can improve the precision of telephone traffic greatly. And the problems of the classes who have discontinuous working time when applied in Particle Swarm Optimization (PSO) were addressed in this paper. The critical codes were protected by encapsulation as dynamic link library (DLL), the difficulties of using Java Native Access calling C++ codes in java environment were solved too. Practices showed that the large-scale calling center intelligent scheduling system can allocate the human resources scientifically, improve the standard of service and productivity greatly. (C) 2011 Published by Elsevier Ltd. Selection and/or peer-review under responsibility of [CEIS 2011]
作者机构：
[黄龙杨; 刘慧; 程恩] Key Laboratory of Underwater Acoustic Communication and Marine Information Technology, Xiamen University, Xiamen 361005, Fujian, China;[李梦醒] Department of Physics and Telecommunications, Hunan City University, Yiyang 413000, Hunan, China
通讯机构：
Key Laboratory of Underwater Acoustic Communication and Marine Information Technology, Xiamen University, China
摘要：
A multirate method with general parameter filter banks for beamforming with constant beamwidth based on harmonic nested array is proposed. The harmonic nested array is composed of several uniformly-spaced linear subarrays, each of which processes an octave subband signal respectively. These nonuniform subband signals are implemented by general parameter filter banks. Each subarray beamforming is carried out by space-frequency signal processing approach, and the number of weights of each subarray is determined by the total frequency bandwidth of its entire subbands correspondingly. This processing architecture based beamformer splits the wideband signal into several narrow subband ones which are processed in parallel, and each subarray is operating with the lowest rate, which contributes to decreasing the computational load significantly and improving the speed and performances as well. Simulations show that the proposed beamformer is competent for constant beamwidth beamforming with much lower computation complexity.
作者机构：
[刘泽民; 李梦醒] School of Telecommunication Engineering, Beijing University of Posts and Telecommunications, Beijing 100876, China;[程恩; 黄龙杨] Laboratory of Underwater Acoustic Communication and Marine Information Technology, Ministry of Education, Fujian Xiamen 361005, China;[李梦醒] Department of Physics and Telecommunication Engineering, Hunan City University, Hunan Yiyang 413000, China
通讯机构：
[Li, M.-X.] S;School of Telecommunication Engineering, Beijing University of Posts and Telecommunications, China
摘要：
A multirate nonuniform subband method with general parameter filter banks for wideband beamforming of harmonic nested array is proposed. The harmonic nested array is composed of several uniformly-spaced linear subarrays, each of which processes an octave subband signal. The nonuniform subband signal is generated by general parameter filter banks. Each subarray beamforming is carried out with space-frequency signal processing approach, and four subarrays share the same weights among themselves. Based on this kind of processing architecture, the proposed beamformer splits the wideband signal into several nonuniform narrow subband ones which are processed in parallel, and only one subarray weights are needed. In this way, the proposed beamformer greatly alleviate burden of demanding too many weights for the arrays and hence contributes to significantly decreasing the computational load and improving the speed as well. Simulations show that the proposed beamformer is competent for wideband beamforming with much lower computation complexity.
摘要：
A improved algorithm to perform channel estimation and equalization for multiple input multiple output(MIMO) systems in frequency and time-selective fading environments is put forward. lt contains two steps: training and tracking. In training phase, improved Kalman filtering, namely robust Kalman filtering(RKF), is exploited to estimate channel impulse response(CIR). After that, in tracking stage,the RKF and minimum mean-square error feedback decision equalizer (MMSE-DFE) cooperate to track the time-varying channel. The RKF recursions is presented and a closed-form solution for baud rate MIMO MMSE-DFE under perfect knowledge of CIR and correct past decisions conditions is derived. In addition, it regards unknown dc-offset due to zero intermediate frequency(IF) at the receiver as the mean of measurement noise, which is estimated as a byproduct through robust Kalman filters. Finally, it is compared with well-known ones,such as least mean-square (LMS), recursive least square (RLS), Kalman filtering (KF). All these show that the proposal exhibits better performance.
