陷波器

Experiments prove that the notch attenuation value can reach -330 dB at arbitrary frequency by adjusting phase-shift parameter.

实验表明：通过改变相移参数值，在任意频率点上陷波器的衰减值可达-330 dB。

along with the development of digital technology,digital filters are widely used in many fields,this paper introduces how to design a iir digital notch filters in matlab environment.the design of digital notch filters can be achieved through three steps:firstly,the design of analog lowpass filter; secondly,it is analog lowpass to analog band stop filter conversion;at last,using the bilinear transformation make the analog notch filters change into digital notch filters.the paper also introduces how to design the transfer function of the digital notch filters using all the zeros and farthest points at the same time,it also introduces the program of the digital notch filters under butterworth analog lowpass prototype.

摘 要：随着数字技术的发展，数字滤波器在许多领域得到广泛的应用。研究一种在matlab语言环境下设计iir数字陷波滤波器的方法，在数字陷波滤波器设计过程中，先进行模拟低通滤波器的设计，然后进行模拟低通/模拟带阻滤波器转换，最后采用双线性变化法将模拟陷波滤波器转化成数字陷波滤波器。提出一种用所有零点和极点来表达数字陷波器传递函数的方法，同时给出以巴特沃斯模拟低通为原型设计数字陷波滤波器的程序。关键词：无限冲激响应；巴特沃斯滤波器；数字陷波滤波器；matlab；双线性变换

The interstage match can be a simple low pass, high pass or intermediate frequency trap.

级间的匹配通过低通、高通或中间通带的陷波器获得。

A dual T network forms a rejecter to suppress the disturbance of the industrial 50Hz frequency.

并且采用双T网络构成的陷波器，对50Hz的工频干扰进行抑制。

The cable TV encrypt solution harasses the technology to pass through several dozens years development, by develops from the most primitive wave trap law to today addressable real-time authorized law.

有线电视的加解扰技术经过几十年的发展，以从最原始的陷波器法发展到了今天的可寻址的实时授权法。

The first one is the gathering and enlargement of the heart electrical signal, including pre-amplification, bandpass analog filter, 50Hz wave trap and the last enlargement circuit.

一是心电信号的采集放大部分：包括前置放大、带通二阶模拟滤波器，50Hz陷波器，及二级放大部分。

The hardware electric circuit includes: Heart electrical signal gathering, enlarges the electric circuit, the band-pass circuit, the host enlargement electric circuit, the 50Hz wave trap and the electricity frequency lifting electric circuit.

硬件电路包括：心电信号的采集、放大电路、带通滤波电路、主放大电路、50Hz陷波器和电频抬升电路。

This instrument generated the sine wave signal which frequency could change in three situations. The sine wave signal inputted to the buffer amplifier, then divided into two groups, a group connected with oscilloscope to survey the peak-to-peak value of fundamental wave, another group connected with wave trap to filter out the fundamental wave, then the oscilloscope was used to survey the various sub-harmonics amplitude of the output.

该仪器是通过设计可变三种频率的正弦波信号发生器产生的正弦波信号，其输出信号经过缓冲放大器，输入放大器后分为两路，一路接入示波器，测量基波幅值；另一路接入陷波器将基波滤去，再用示波器测量其输出各次谐波幅值。

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与audioedit豪华您可以执行双程转换之间的CD ， MP3等， mp2 ， wav ，的WMA ，和OGG ；打开，创建和保存音频文件中的任何支持的格式（也可以保存的任何部分，加载文件到磁盘作为一个新的文件）；显示音频数据的波形（放大充分，放大，缩小，缩小垂直）；播放音频文件或任何部分的文件；记录音频数据从一个麦克风或任何其他可输入设备；编辑音频文件的视觉（剪切，复制，删除选择，剪裁，修剪，粘贴，粘贴文件，混音，混音，从文件）；适用於各种效果（放大，压缩，延时，均衡，淡出在和淡出，镶边，反转，正常化，相位，混响，扭转，收缩，沉默，舒展，颤音）；适用於不同的过滤器，以任何选定的部分音频文件（带通滤波器，高通滤波器，高货架过滤器，低通滤波器，低大陆架滤波器，陷波器）；插入噪音或沉默到音频文件；插入信息转化为音频文件（专辑名称，艺人，版权，流派，标题，年）；完整的，多层次，撤消和重做的能力；先进，烧伤证明音频CD烧录；得多。

Experiments show that the digital trap filter based on window function method of FIR can efficiently reduce the power line interference in SEMG.Furthermore,the frequency around 50 Hz does not be obviously influenced.

实验证明，采用基于窗函数法的FIR原理设计的50 Hz数字陷波器能有效滤除SEMG中的工频干扰并基本不影响50 Hz周围有效SEMG的获取。

The split between the two groups can hardly be papered over.

这两个团体间的分歧难以掩饰。

This approach not only encourages a greater number of responses, but minimizes the likelihood of stale groupthink.

这种做法不仅鼓励了更多的反应，而且减少跟风的可能性。