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TD-SCDMA系统中的DwPTS同步技术 被引量:4
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作者 栗世涛 陈贤亮 《信息安全与通信保密》 2007年第9期88-89,92,共3页
文章针对TD-SCDMA子帧结构的特点,在对TD-SCDMA中的下行同步过程做了简要分析之后,给出了解决下行同步中搜寻DwPTS的方法。同时,论文还介绍了使用功率特征窗搜寻DwPTS的算法,并用所述的方案进行了MATLAB仿真,很好地实现了下行同步,最后... 文章针对TD-SCDMA子帧结构的特点,在对TD-SCDMA中的下行同步过程做了简要分析之后,给出了解决下行同步中搜寻DwPTS的方法。同时,论文还介绍了使用功率特征窗搜寻DwPTS的算法,并用所述的方案进行了MATLAB仿真,很好地实现了下行同步,最后提出了存在的一些关键性问题。 展开更多
关键词 TD-SCDMA dwpts SYNCHRONIZATION 时序搜索算法 Midamble
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无线电能传输零电压开关角跟踪和动态电容补偿矩阵复合控制策略
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作者 李争 唐明磊 +2 位作者 解波 朱乙丁 孙鹤旭 《电工技术学报》 EI CSCD 北大核心 2024年第12期3602-3615,共14页
为了保证动态无线电能传输(DWPT)系统工作于较高的电能传输效率和传输功率,减小由于系统参数变化导致的传输功率和传输效率的下降。该文提出一种零电压开关角(ZVSA)跟踪和动态电容补偿矩阵(DCCM)相结合的无线电能传输系统频率跟踪控制... 为了保证动态无线电能传输(DWPT)系统工作于较高的电能传输效率和传输功率,减小由于系统参数变化导致的传输功率和传输效率的下降。该文提出一种零电压开关角(ZVSA)跟踪和动态电容补偿矩阵(DCCM)相结合的无线电能传输系统频率跟踪控制策略。采用电流传感器来获取谐振电流的相位,并利用处理器产生的参考信号来测量谐振电流的相位。微控制根据频率漂移的程度计算补偿电容的大小,粗略地将自然谐振频率调至85 kHz,然后系统自动跟踪谐振电流相位,对谐振频率精确跟踪。该方法通过直接对相位检测电路输出的直流信号进行采样,轻松地获取高频电流的相位,大大降低了对微控制器的占用。该文提出的控制策略和系统结构结合了模拟电路和数字控制的优点,不仅对系统参数变化有高动态响应,而且极大地节省了处理器资源。 展开更多
关键词 动态无线电能传输(DWPT) 零电压开关角(ZVSA) 动态电容补偿矩阵(DCCM) 频率跟踪
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Designing an Effective Method for Automatic Electric Vehicle Charging Stations in a Static Environment
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作者 Md. Robiul Islam Maisha Islam +2 位作者 Tania Sarkar Hanif Mia Md. Asadullah 《Journal of Power and Energy Engineering》 2024年第1期15-28,共14页
This article outlines an Effective Method for Automatic Electric Vehicle Charging Stations in a Static Environment. It consists of investigated wireless transformer structures with various ferrite forms. WPT technolog... This article outlines an Effective Method for Automatic Electric Vehicle Charging Stations in a Static Environment. It consists of investigated wireless transformer structures with various ferrite forms. WPT technology has rapidly advanced in the last few years. At kilowatt power levels, the transmission distance grows from a few millimeters to several hundred millimeters with a grid to load efficiency greater than 90%. The improvements have made the WPT more appealing for electric vehicle (EV) charging applications in both static and dynamic charging scenarios. Static and dynamic WEVCS, two of the main applications, are described, and current developments with features from research facilities, academic institutions, and businesses are noted. Additionally, forthcoming concepts based WEVCS are analyzed and examined, including “dynamic” wireless charging systems (WCS). A dynamic wireless power transfer (DWPT) system, which can supply electricity to moving EVs, is one of the feasible alternatives. The moving secondary coil is part of the dynamic WPT system, which also comprises of many fixed groundside (primary) coils. An equivalent circuit between the stationary system and the dynamic WPT system that results from the stationary system is demonstrated by theoretical investigations. The dynamic WPT system’s solenoid coils outperform circular coils in terms of flux distribution and misalignment. The WPT-related EV wireless charging technologies were examined in this study. WPT can assist EVs in overcoming their restrictions on cost, range, and charging time. 展开更多
关键词 Dynamic Wireless Power Transfer (DWPT) Wireless Charging System (WCS) Electric Vehicle (EV) Dynamic Performance
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发电机组转子机械故障诊断的DWPT方法 被引量:2
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作者 侯荣涛 郭松林 任朝晖 《汽轮机技术》 北大核心 2003年第2期119-121,共3页
研究了小波理论及小波包(DWPT)分解技术在发电机组故障特征提取和诊断中的应用。针对发电机组的常见故障及其表现特征,结合对某故障发电机组的实际测试,利用小波包分解技术对该发电机组的振动信号进行了分析诊断,得到了与实际情况完全... 研究了小波理论及小波包(DWPT)分解技术在发电机组故障特征提取和诊断中的应用。针对发电机组的常见故障及其表现特征,结合对某故障发电机组的实际测试,利用小波包分解技术对该发电机组的振动信号进行了分析诊断,得到了与实际情况完全相同的结果。研究结果表明:利用小波消噪方法和小波包分解技术在时域内能更准确地判断发电机组的工作状态,该方法也为其它复杂机械的故障诊断提供了新路径。 展开更多
关键词 发电机组 转子 机械故障 故障诊断 DWPT方法 小波理论 小波包
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基于C8051F340控制的TD直放站控制方案设计
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作者 周业平 邓文浪 周常青 《微型机与应用》 2010年第12期22-25,共4页
介绍一种基于C8051F340快速单片机控制的直放站设计;采用GPS同步法,按时隙功率控制,自动增益控制AGC环路,系统的非线性指标良好、抗干扰性强、可靠性高。比以功率检测的同步方法和基于特征窗搜索的同步方法实现简单,应用范围更广,可用... 介绍一种基于C8051F340快速单片机控制的直放站设计;采用GPS同步法,按时隙功率控制,自动增益控制AGC环路,系统的非线性指标良好、抗干扰性强、可靠性高。比以功率检测的同步方法和基于特征窗搜索的同步方法实现简单,应用范围更广,可用于任何无线直放站应用场合,特别适用于干放及无线射频交换场合。 展开更多
关键词 3G TD-SCDMA 直放站 同步和切换 dwpts 按时隙功率控制
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基于DSP2812的TD-SCDMA直放站设计与实现
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作者 周业平 邓文浪 《微计算机信息》 2010年第29期125-126,共2页
随着第三代移动通信(简称3G)系统TD-SCDMA(时分同步码分多址)技术的不断成熟和3G牌照的发放,无线网络的建设和优化及TD-SCDMA直放站的广泛应用将必不可少;本文介绍了一种基于DSP2812的,抗干扰性强,TD-SCDMA帧同步跟踪实现及按时隙功率... 随着第三代移动通信(简称3G)系统TD-SCDMA(时分同步码分多址)技术的不断成熟和3G牌照的发放,无线网络的建设和优化及TD-SCDMA直放站的广泛应用将必不可少;本文介绍了一种基于DSP2812的,抗干扰性强,TD-SCDMA帧同步跟踪实现及按时隙功率控制的设计。 展开更多
关键词 3G TD-SCDMA 直放站 同步和切换 dwpts 按时隙功率控制
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TD-SCDMA NodeB的自启动自适应组网
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作者 袁乃华 佟学俭 《电信科学》 北大核心 2009年第3期112-115,共4页
在现有的网络建设和优化中,基本是通过网络先期规划和RNC的设置来触发NodeB建立小区,并通过路测仪器人工干预的方式不断地测试网络性能,如网络覆盖等情况,多次反复调整网络参数进行网络性能优化,以达到网络性能满足应用需求,网络组网和... 在现有的网络建设和优化中,基本是通过网络先期规划和RNC的设置来触发NodeB建立小区,并通过路测仪器人工干预的方式不断地测试网络性能,如网络覆盖等情况,多次反复调整网络参数进行网络性能优化,以达到网络性能满足应用需求,网络组网和网络优化的成本高,效率低。本文基于鼎桥公司NodeB的设计,提出了TD-SCDMA NodeB的自启动自适应组网和网络优化方案。NodeB可以根据E1/FE配置,实现NodeB在ATM和/或IP方式下的自启动,下载配置和软件;小区激活后,自动搜索相邻的小区,根据网络的业务模型设置,计算相邻小区的覆盖情况,并计算出本小区的最佳功率覆盖参数,达到网络最优覆盖配置并减少对周围小区的干扰。在整个网络运行期间,也可以触发网络中各小区检测周围的情况,输出区域内网络的性能参数,进行网络优化和网络监测。 展开更多
关键词 TD-SCDMA NODEB BootP DHCP dwpts SYNC-DL SYNC-UL BCH
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A Robust Denoising Algorithm for Sounds of Musical Instruments Using Wavelet Packet Transform
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作者 Raghavendra Sharma Vuppuluri Prem Pyara 《Circuits and Systems》 2013年第7期459-465,共7页
In this paper, a robust DWPT based adaptive bock algorithm with modified threshold for denoising the sounds of musical instruments shehnai, dafli and flute is proposed. The signal is first segmented into multiple bloc... In this paper, a robust DWPT based adaptive bock algorithm with modified threshold for denoising the sounds of musical instruments shehnai, dafli and flute is proposed. The signal is first segmented into multiple blocks depending upon the minimum mean square criteria in each block, and then thresholding methods are used for each block. All the blocks obtained after denoising the individual block are concatenated to get the final denoised signal. The discrete wavelet packet transform provides more coefficients than the conventional discrete wavelet transform (DWT), representing additional subtle detail of the signal but decision of optimal decomposition level is very important. When the sound signal corrupted with additive white Gaussian noise is passed through this algorithm, the obtained peak signal to noise ratio (PSNR) depends upon the level of decomposition along with shape of the wavelet. Hence, the optimal wavelet and level of decomposition may be different for each signal. The obtained denoised signal with this algorithm is close to the original signal. 展开更多
关键词 DWPT Adaptive BLOCK DENOISING PEAK Signal to Noise Ratio WAVELET THRESHOLDING
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A Novel Transceiver Architecture Based on Wavelet Packet Modulation for UWB-IR WSN Applications
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作者 Mohamed Tabaa 《Wireless Sensor Network》 2016年第9期191-209,共19页
In last few years, several recent developments concern a new proposed techniques of communication for WSN (Wireless Sensors Network) using a complex methods and technics. This network is considered a future platform f... In last few years, several recent developments concern a new proposed techniques of communication for WSN (Wireless Sensors Network) using a complex methods and technics. This network is considered a future platform for many applications like: medical, agriculture, industrial, monitoring and others. The challenge of this work consists in proposing a new design of transceiver for WSN based on IDWPT (Inverse Discrete Wavelet Packet Transform) in emitter and DWPT (Discrete Wavelet Packet Transform) in receiver for mono and multi users using AWGN Channel. We will propose in this paper, a new concept of impulse radio communication for multiband orthogonal communication for UWB (Ultra-wideband) applications. The main objective of this work is to present a new form of pulse communication adapted to low through-put short-range applications and is scalable according to the type of use but also the number of sensors. 展开更多
关键词 Wireless Sensor Networks (WSN) Discrete Wavelet Packet Transform (DWPT) Impulse Radio (IR) Ultra-Wideband (UWB) TRANSCEIVER
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TD-SCDMA系统下行链路同步技术研究 被引量:4
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作者 赵慧慧 易准 安世全 《通信技术》 2007年第11期199-201,243,共4页
文中首先对TD-SCDMA系统同步技术进行了系统的阐述,随后介绍了无线接口同步中下行链路初搜的几种同步方法的原理,同时给出了各自的改进方案,最后通过其算法复杂度、仿真准确性等方面的性能比较来分析各下行链路同步方法的优缺点。
关键词 时分同步码分多址 同步 dwpts SYNC—DL 特征窗 相关法
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