New progress of mm-wave radio-over-fiber system based on OFM

This paper presents an overview on new progresses-of millimeter wave (mm-wave) radio-over-fiber (RoF) system based on mm-wave generation by optical frequency multiplication (OFM), including gen-eration of high-order optical side modes by optical modulation using dual-drive Mach-Zehnder modulator (DD-MZM) and enhancement of high-order optical side mode induced by selective amplification due to stimulated Brillouin scattering (SBS). The paper describes OFM by using DD-MZM in principle and verifies it in an experimental bidirectional 40GHz RoF system. SBS amplification enhances the generated information-bearing mm-wave in downlink and also helps in producing a pure reference mm-wave for radio frequency-intermediate frequency (RF-IF) down-conversion in uplink. These efforts pushed the OFM technology of mm-RoF systems to achieve more and more feasibility and cost-effectiveness.     

Research on periodic switching frequency modulation for conducted EMI suppressing in power converter

This paper is devoted to explore modulation techniques with deterministic profiles reducing the peak EMI in a power converter. In this paper, the effect of primary modulation parameters such as modulation profile, modulation index and modulation frequency on peak EMI suppression is numerically simulated and discussed while a fully integrated spread spectrum clock generator (SSCG) with triangular modulation is presented whose major advantages are good robustness, small size and low-power consumption. The proposed SSCG has been applied to a fly-back switching converter and the results of the experiment confirm the proposed circuit.     

火电厂SIS的规划设计研究

根据大唐国际张家口发电厂分散控制系统（DCS，dlstributed control system）的应用现状，简要介绍了火电厂管理监控信息系统（SIS，supervisory information system）建设的必要性、指导思想和总体目标。系统阐述了火电厂厂级SIS的规划设计模型及实时数据库系统（PI）接口的研究思路；以期抛砖引玉，提高火电厂SIS建设水平。提高电厂管理水平与经济效益。     

SVPWM Techniques and Applications in HTS PMSM Machines Control

This paper introduces the principle of space vector pulse width modulation （SVPWM）, and discusses a method for implementing the SVPWM based on MATLAB/SIMULINK, as well as modeling of AC servo system with permanent magnet synchronous motor （PMSM）. Simulation results show that the model is effective, and the method provides a frame of reference for software and hardware designs which can be applied in high temperature superconducting （HTS） flywheel energy storage system （FESS） and linear motor （LM）.     

Standard Analysis for Transfer Delay in CTCS-3

According to the standard for the GSM for railway (GSM-R) wireless systems in China train control system level 3 (CTCS-3),the control data transfer delay should be no larger than 500ms with greater than 99％ probability.Coverage of both non-redundant networks and intercross redundant networks and cases of single Mobile terminals (MTs) and redundant MTs on one train are considered,and the corresponding vehicle-ground communication models,delay models,and fault models are constructed.The simulation results confirm that the transfer delay can meet the standard requirements under all cases.In particular,the probability is greater than 99.996％ for redundant MTs and networks,and the standard of transfer delay in CTCS-3 will be improved inevitably.     

利用拟合优度检验的NPLSC-DSSS信号伪码盲估计

针对非周期短码扩频长码加扰直扩(NPLSC-DSSS)信号的伪码估计问题,该文首先给出了m序列三阶相关函数(TCF)共同峰理论和NPLSC-DSSS信号TCF估计量的概率函数。其次,利用TCF峰的共轭系特性构建了TCF峰值序列,提出了TCF共同峰检测的二元假设模型和利用拟合优度检验的TCF共同峰精检测算法。同时,为提高伪码估计性能,该文利用正反向TCF三阶相关峰性质和共轭系TCF峰值点累加和递增性质排除大量伪峰。最后通过矩阵斜消法实现长短伪码的盲估计。仿真结果表明,该文方法在低信噪比条件下能够有效估计NPLSC-DSSS信号的伪随机码。