查询词典 waveform digitization

The primary work in this dissertation:(1) This dissertation compares the differences and similarities between direct digital waveform synthesizer and direct digital frequency synthesizer.

本文的主要工作之处在于：(1)对直接数字波形合成及直接数字频率合成两种数字波形产生方法进行了分析对比。

Direct digital waveform synthesizer; linear frequency modulated signal; digital-to-analog conlerter; pulse compression

直接数字波形合成；线性调频信号；数模转换器；脉冲压缩

This paper systematically researched this sort of nonuniformly sampled signals'digital spectrum structure, signal-to-noise ratio , the response of D/A converter with nonuniformly sampled signals, the algorithm for estimating timing offsets, the relationship between the discrete time expression of the total energy and the continuous time expression, the estimation of the average power, the algorithm of recovery and application in designing and analyzing the digital waveform synthesizer.

本文全面系统地研究了这类周期性非均匀采样信号的数字谱结构，信噪比表达式，数模转换器对非均匀采样信号输入的响应，误差校正算法，时域与频域的能量对应关系，对功率测量的影响，内插恢复算法，以及在设计和分析数字波形合成器中的应用。

Direct digital waveform synthesizer is a digital method that the radar signal is generally generated.The error resource of DDWS is presented.The principle that signal is reconstructed in digital-to-analog converters is analyzed in the DDWS structure.

介绍了直接数字波形合成(direct digital waveform synthesizer，DDWS)的误差来源，分析了DDWS结构中其数模转换器信号重构机理，比较研究了DAC信号重构误差对输出信号脉冲压缩结果的影响。

Emphasis is laid on the research progress in the field of new generation speech synthesis technology contributed by USTC iFlytek speech laboratory, which includes integration articulatory and acoustic features for improving the flexibility of acoustic parameter generation; a minimum generation error criterion proposed to replace maximum likelihood for improving synthesized speech quality; use of unit selection and waveform concatenation to replace parametric synthesizer, thus effectively avoiding the limitation of speech quality in HMM based parametric synthesis.

重点介绍中国科学技术大学讯飞语音实验室在发展新一代语音合成技术中的贡献，包括：融合发音器官参数与声学参数，提高声学参数生成的灵活性；以最小生成误差准则取代最大似然准则，提高合成语音的音质；使用单元挑选与波形拼接方法取代参数合成器重构，从根本上改善HMM参数语音合成器在合成语音音质上的不足。

In chapter 4, control strategy for standard vibrators test table waveform is studied.

第四章阐述了标准振动台台面波形控制策略。

In chapter 3, the mechanism of test table waveform distortion generated by factors of ultra-low-frequency standard vibrator is studies systematically.

第三章对超低频标准振动台的台面波形失真机理进行了系统全面的分析。

In chapter 3, the mechanism of test table waveform distortion generated by all factors in ultra-low frequency standard vibrator is studied systematically for the first time. First, the expression of suspension spring is obtained according to the experimental results.

首先阐述了振动传感器的特点及其校准方法，指出了建立超低频标准振动计量的迫切性和重要性；然后回顾了国内外标准振动计量技术的研究概况；接着指出了超低频标准振动计量存在的问题并指明了研究方向，另外，还对标准振动计量中的自动控制研究情况进行了回顾和评述；最后指出本论文研究的主要内容。

Altera Corporation system to the Cyclone FPGA series of digital platform, microprocessor, bus, Digital Frequency Synthesizer, memory and I / O interface hardware concentrated in an FPGA, the use of direct digital frequency synthesis technology and digital modulation waveforms required to achieve the rise, Using FPGA ROM storage of the DDS waveform table, and make full use of on-chip resources, improve the system's accuracy, stability and robustness.

系统以 ALTERA公司的 Cyclone 系列 FPGA 为数字平台，将微处理器、总线、数字频率合成器、存储器和 I/O 接口等硬件设备集中在一片 FPGA 上，利用直接数字频率合成技术、数字调制技术实现所要求波形的产生，用 FPGA 中的 ROM 储存 DDS 所需的波形表，充分利用片上资源，提高了系统的精确度、稳定性和抗干扰性能。

Obtains after the number/mold transformation as well as the filter needs the signal the profile, his table look-up synthetic waveform method may have the random profile request satisfiedly.

经数/模转换以及滤波后得到所需信号的波形，他的查表合成波形的方法可以满足产生任意波形的要求。

Objective:To compare the response control and attention of Schizophrenic patients with that of the healthy controls by Integrated Visual and Auditorycontinuous performance test. To quantitate the impairment of cognitive function in patients, and to explore the relationship between cognitive function and the severity of the disorder.

目的：探讨精神分裂症病人在IVA持续操作测试中的反应控制能力、注意力等，并与健康人进行比较，从而量化精神分裂症病人的认知功能损害，并进一步探讨其认知功能与疾病严重程度的关系。

Main effective factors including subcooling degree, mechanical vibration, gas hydrate reformation, environment temperature, noncondensing gas and surfactant are analyzed.

指出过冷度、机械振动、重复生成水合物、环境温度、不凝性气体、添加剂是影响气体水合物生成的主要因素，还对R152a水合物的放冷进行了实验研究。