查询词典 frequency conversion

In wheel speed signal processing,a critical frequency/voltage conversion circuit is added.

设计考虑的重点是转速较低时角速度传感器信号的处理问题。

Based on surveying the development of variable frequency power supply and analyzing its development tendency, and considering the practical features of the assignment, the conversion system is designed as follows: it selects the 3-phase Pulse Width Modulation Engine SA4828 as the PWM control signals generator; it chooses the single-chip-computer PIC16F877 as the microcontroller, which integrated the A/D modulation, which cuts down the complexity of the hardware system and strengthens the dependability of the system.

在论述和分析了变频电源及其控制技术发展的概况和趋势的基础上，结合本课题任务的实际要求，设计了一套中小功率的逆变电源。系统中PWM控制信号采用专用集成芯片SA4828生成，减轻了控制器的工作量也提高了系统的可靠性。控制器选用集成了A/D转换器的单片机，使得系统的硬件复杂性降低，提高了可靠性。

By utilizing the cross-gain modulation effect and the period-one oscillation harmonic frequency-locked in an optically injected semiconductor laser, we can extract the wavelength conversional individual channel optical clock from the optical-time-division-multiplexing signal. In a FP-LD, we numerically simulate the extraction of 20 GHz optical clock at 1550 nm from the 2×20 Gb/s OTDM signal at 1555 nm, and experimentally obtain the -105 dBc/Hz phase noise frequency division clock of 12.36 GHz to 6.18 GHz with simultaneous wavelength conversion from 1550.24 nm to 1545.91 nm.

采用一个FP半导体激光器作为全光分路时钟提取及波长转换器，数值模拟实现了从波长为1555 nm、速率为2×20 Gb/s的光时分复用信号中提取出波长转换为1550 nm、重复频率为20 GHz的分路光时钟，实验完成了从波长为1550.24 nm、重复频率为12.36 GHz光脉冲信号中提取出相位噪声为-105 dBc/Hz的波长为1545.91 nm、重复频率6.18 GHz的分频光时钟。

A detailed analysis of the main circuit introduction, control method and working principle of the direct-drive wind energy conversion system are given to introduce the two important parts a of this paper: First part is the control method of the multiple boost convertor, the important instantaneous current control method of this paper is given through the analysis of the main circuit structure, control method and working principle. Then a steady-state analysis for low-frequency, a high-frequency component analysis, and a closed-loop tracking performance analysis for dynamic response are provided to analyze the method proposed; And the second part is the control method of invertor.

在系统变流器整体结构分析的基础上，引出本文重点研究的两个变流环节的控制：第一部分是系统升压斩波器的控制，通过分析相关主电路结构、原理，建立了数学模型，引出本文重点研究的瞬时值控制策略的概念和具体实现，并对升压斩波器的瞬时值控制策略进行了详细的高频、低频模型分析和稳态、动态性能分析；第二部分是系统并网逆变器的控制，通过对逆变器主电路的数学建模和控制要求分析，研究了并网逆变器的瞬时值控制策略，包括电感电流控制内环和直流电压控制外环的具体设计和实现方法。

According the principles of scalar network analyzer and vector network analyzer the authors introduced methods to measure conversion loss of frequency translating devices using scalar network analyzer and methods to measure conversion loss and phase using vector network analyzer.

摘 要：网络分析仪为测量变频器件提供了快速而准确的测量方法，根据标量网络分析仪和矢量网络分析仪的测量原理，详细介绍了用标网测量变频器变频损耗的方法，以及用矢网测量变频损耗和相位的方法。

The results showed that the effect of feeding frequency on the growth of Sparus macrocephalus arose from the changes of feed conversion efficiency, while the ingestion rate was not significantly affect by feeding frequency.

结果表明：(1)摄食率不受饲喂频率的显著影响，饲喂频率影响黑鲷的生长是由饲料转化率的改变引起的。

It is composed of six parts: PCI Bus interface module, signal generator, signal adjustor, gain and phase detector, A/D conversion module and control and data process module. The system can measure the gain and phase curves of the crystal with the frequency range from 1MHz to 150 MHz. Crystal parameters can also be calculated, such as resonant frequency, series resistance, shunt capacitance, motion capacitance, motion inductance and Q factor, etc.

该测试卡以 IEC 444 标准为测量原理，由 PCI 总线接口模块、信号发生器、信号调理模块、增益相位检测电路、A/D 转换模块等部分组成，能够有效测量 1MHz～150 MHz 频率范围的晶振的增益与相位特性、串并联谐振频率、等效电阻、动态电容、动态电感、品质因数和负载频率等主要电参数。

This invention relates to three-dimensional seismic data processing quality monitoring technology. Selecting time-window and analysis frequency for FFT to obtain frequency-domain conversion result for every channel; taking mean-filter to obtain the statistic excited energy or noise disturbance; plotting all results on plane graph to monitor the 3D excited energy or noise disturbance; taking normalization and autocorrelation to all earthquake channel; summating all autocorrelation statistic result to obtain opposite statistic autocorrelation result; finding out and plotting the zero-crossing of autocorrelation on plane position for monitoring excited wavelet.

本发明涉及一种三维地震资料处理质量监控技术，步骤是：选定时窗和分析频率；对某炮各地震道在时窗内做快速富立叶变换，得到道数据在频率域变换结果；对同炮的所有地震道做频率域中值滤波，得到该炮的统计激发能量或噪声干扰量结果；将所有炮的计算结果绘到各炮点平面图上，监控三维激发能量或噪声干扰；对地震数据某炮的各地震道做归一化自相关；对同炮的所有地震道的自相关统计求和，得到该炮的统计自相关结果；寻找该炮统计自相关的零交叉时，将所有炮的零交叉时绘到各炮点平面位置上，完成激发子波监控。

The frequency synthesizer includes a completely on-chip LC VCO and a 90 degrees phase splitter for generating the I and Q LO signals to the down-conversion mixers in receive mode and up-conversion mixers in transmit mode.

频率综合者在-芯片LC VCO上-完全包含a和一产生我和 Q北美印第安人90度分相器为向挫折-转换混合者发信号示意在朝派收到方式和沿着-转换混合者在朝派传送方式。

The frequency synthesizer includes a completely on-chip LC VCO and a 90 degrees phase splitter for generating the I and Q LO signals to the down-conversion mixers in receive mode and up-conversion mixers in transmit mode.

频率合成器完全地包括一块在芯片LC VCO 并且90 程度逐步采用分离机为引起I 并且Q 低信号对下来转换搅拌器接受方式并且转换搅拌器传送方式。

On the other hand, the more important thing is because the urban housing is a kind of heterogeneity products.

另一方面，更重要的是由于城市住房是一种异质性产品。

Climate histogram is the fall that collects place measure calm value, cent serves as cross axle for a few equal interval, the area that the frequency that the value appears according to place is accumulated and becomes will be determined inside each interval, discharge the graph that rise with post, also be called histogram.

气候直方图是将所收集的降水量测定值，分为几个相等的区间作为横轴，并将各区间内所测定值依所出现的次数累积而成的面积，用柱子排起来的图形，也叫做柱状图。