查询词典 band filter

The study has focused on: 1 The research background and the current state of the power measurement were analyzed systematically, and then wavelet-based power measurement algorithm was certified feasible for astable signals; 2 We developed a new method of RMS and power measurement based on Dmeyer wavelet. After that three other wavelet measurement approaches were compared with Dmeyer wavelet-based measurement approach. Then the impact on measurement errors of amplitude frequency property and energy leakage of wavelet filter banks were deeply researched, and some measures were proposed to reduce it; 3 We developed a new strategy of power measurement algorithm based on lifting wavelet, which had calculation advantage compared with the first wavelet, so that it was more suitable for the realization of hardware; 4 The running system of wavelet-based power measurement algorithm based on DSP was proposed, and then it was realized on ICETEK-VC5416-A EVM board; 5 Existing problems and the further research direction of wavelet-based power sub-band measurement algorithm was discussed.

本文对基于小波变换的功率测量算法展开深入的分析研究，主要内容有：1）系统地分析了功率分解测量的研究背景、国内外的研究现状，并从能量守恒的角度验证了小波功率分频带测量算法在非平稳信号条件下的可行性；2）首次提出了Dmeyer小波变换有效值与功率的测量方法，进而通过对该方法与3种已经提出的小波测量方法的对比分析，深入研究了小波滤波器组的幅频特性和能量泄漏特性对测量误差的影响，并针对电网谐波的特点提出了减小影响的相关措施；3）首次提出了二代小波功率测量算法，对比一代小波功率分频带测量算法，它大大减少了算法实现的运算量及内存的需求量，从而更适合于硬件的实时实现；4）提出了小波功率分频带测量算法的DSP实现方案，并在ICETEK-VC5416-A EVM板上进行了实现；5）探讨了小波功率分频带测量算法目前仍存在的问题，并提出了进一步的研究方向。

Simulation results show that, for the fixed sampling frequency, the error rises with the frequency increasing of periodic signal, and decreases with the attenuation time constant increasing of non-periodic signal. The sampling frequency determines the upper limit of appropriate frequency band directly. The research provides the basis for the selection of cutoff frequency in filter design.

仿真结果表明，在采样频率确定时，对于周期信号，计算误差随频率的增加而增大，而对于非周期信号，计算误差随衰减时间常数的增大而减小，采样频率大小决定了插值法用于分布参数模型的适用频带上限，该研究为滤波器设计中截止频率的选择提供了依据。

An example of band-pass filter with center frequency in C band is given.

给出了一个中心频率在C波段的带通滤波器设计实例。

In this thesis, we present a substrate integrated waveguide-based band-pass filter with wide stop-band rejection property.

在本篇论文中，我们提出具有高选择性之基板合成波导带通滤波器。

Achieve a common high-pass, low-pass, band-pass and band stop filter function.

实现一个通用的高通、低通、带通和带阻滤波器函数。

With internationally latest studies, the paper also proposes some biquadrate filters which are capable to perform the functions of second-order low pass、 high pass、 band pass、 band stop、 all pass filtering by selecting one of the three inputs or their proper combinations from the same configuration, furthermore whose natural frequency and the quality factor can be tuned independently. Then a continuous-time biquadratic filter using CCCII is proposed, which can be used in hearing aids and in other analog signal processing applications. Lastly a current mode and a voltage mode novel n-order filters of multifunction are presented. Not all both of the n-order filters are electronic tunable,but also they are integrated conveniently and compatible with VLSI technology.

尽量的全面归纳以电流控制传送器为有源器件的有源网络模拟电路、模拟信号处理电路，借鉴国内外最新研究成果，提出两种基于CCCⅡ的双二阶滤波器，这些电路在不需要改变电路结构的情况下，能同时实现低通、高通、带通、带阻或全通多种滤波功能，并且滤波器的特征频率ω_0和品质因数Q可实现独立调节；其中一种基于CCCⅡ的双二阶滤波器，首次提出将CCCⅡ应用于可编程助听器领域；最后设计了两种高阶滤波器，电压模式和电流模式各一种，这两种滤波电路均能实现多种滤波功能，能实现滤波器参数的电调谐，具有易于集成等优点。

Double channel bandpass sampling method for wide band IF signal is presented to settle the problem of blind zone,which exchanges one more sampling channel for simplification of clock circuit and band pass filter.As a practical reconnaissance receiver, real-time processing performance must be considered.Digital channelizing method lays the base of parallel processing by multi DSP chips and discarding of the redundant data resulting from double channel bandpass sampling.

针对带通采样存在着频率覆盖盲区的问题，提出了宽带中频信号双通道带通采样的方法，通过增加一个采样通道既解决了传统处理盲区方法中设计复杂采样时钟电路、高矩形系数滤波器的困难，还缓解了后续DSP处理压力。

Having studied the digital down-conversionprocess of IF signal before the base band process which follows A/D conversion in wireless communication,the paper puts forward a new idea of utilizing the FPGA to realize multi-channel digital signal DDC.Through analyzing the features and performances of CIC filters,HB filters and multiphase-filter,we combine them with decimators and decimate the A/D data,thus reducing the digital signal rate and the load of DSP when processing the base band signal.

软件无线电技术是在通用的开放式无线电智能平台上，通过安装不同的软件来完成各种通信功能，其结构的基本特征之一就是使A/D变换尽量靠近射频端，目前的方案是在中频对模拟信号进行数字化，对中频数字信号进行下变频处理，使数字信号量降低到高速DSP能够处理的程度[1]。

In this thesis, we developed an electrically tunable band-pass filter. The filter contains multiple sections of open-loop ring resonators and varactors.

在这篇论文中，我们发展了一个电子式可调带通滤波器，这滤波器由开回路环形共振器和varactor所构成。

A series of microwave filters and diplexers are designed by optimization and fabricated based on HFSS and the programs written by myself.A combline SIR cross-coupled filter is designed by HFSS. Cha.5 presented the design of dual-band bandpass filter and corner diplexer.

第六章利用自编程序设计了几种较为新颖的基片集成波导滤波器，其中包括多频带阻滤波器、交叉耦合吸收式滤波器和带Triplet拓扑的广义切比雪夫平面双工器。

Neither the killing of Mr Zarqawi nor any breakthrough on the political front will stop the insurgency and the fratricidal murders in their tracks.

在对危险的南部地区访问时，他斥责什叶派民兵领导人对中央集权的挑衅行为。

In fact,I've got him on the satellite mobile right now.

实际上 我们已接通卫星可视电话了