Description: matlab去除50hz噪声。
我用电脑录了一段声音，里面有50hz的周期噪声（因为受交流电干扰）。而我自己的声音频率最低是90hz。我使用了一个10阶butterworth高通滤波器，边带是70hz(介于50跟90之间)。
问题是，这不能直接用。因为声音文件的采样率是22k，70相对于22k来说太小了。所以我得先把我的声音欠采样，然后再滤波，然后再插值。-matlab remove 50hz noise. I used the computer recorded a voice, there are 50hz cycle noise (due to AC interference). I own voice is the lowest frequency of 90hz. I use a 10-order Butterworth high-pass filter, edge belt is 70hz (the range between 50 to 90). The problem is that this can not be directly used. Because the sound files of the sampling rate is 22k, 70 compared with the 22k run too small. So I have to put my voice due to sampling, and then filtering, and then interpolation. Platform: |
Size: 6144 |
Author:张文斌 |
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Description: 电脑经常放置在有较强的磁场环境下就有可能造成硬盘上数据的损失 甚至这种强磁
场还会使电脑出现一些莫名其妙的现象如 显 示器可能会产生花斑抖动等这种电磁干
扰主要有 音响设备 电机 大功能电器 电源 静电以及较大功率的变压器如 UPS 甚至-Computers are often placed in a strong magnetic field environment is likely to result in the loss of data on your hard disk or even such a strong magnetic field will make a number of computer display inexplicable phenomena such as jitter may be piebald electromagnetic interference, such as this there are sound major function of the electrical equipment, static electricity and electrical power transformers such as greater power and even UPS Platform: |
Size: 1181696 |
Author:付采 |
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Description: 此题目是通过键盘来实现密码输入是否正确，正确的时候数码管亮，否则发出报警声。
判断是按键还是干扰是非常有用的，它体现了一个系统的抗干扰能力。高低电平在瞬间的变换是很正常的，如果没有这条语句，系统很容易出错。
其中2秒是由定时器0来完成的。
在程序的定时器中断中，用switch代替了if else结构，使得程序的可读性大大增强。
TH0 = (65536-50000) / 256
TL0 = (65536-50000) 256 使得TH0 = 3CH, TL0 = B0H,由于该单片机的晶振为12MHz 因此定时时间就为0.05ms.在定时器中断服务程序中用FLASH计数，当计数达到40时正好是2秒。-This topic is through the keyboard to realize the correct password is correct, when GuanLiang digital alarm sound, otherwise.
Judgment is a key or interference is very useful, it reflects the anti-interference ability of a system. High level in the instant transformation is very normal, if not this statement, the system is very easy to make a mistake.
2 seconds is accomplished by the timer 0.
In the process of the timer interrupt, switch with replaced if else structure, make the readability of the procedures enhanced greatly.
TH0 = (65536-50000)/256,
TL0 = (65536-50000) 256, Make TH0 3CH, TL0 = = B0H, because the MCU crystals for 12MHz, So regularly time is 0.05 ms in timer interrupt service routines, when using FLASH counting 40 count when exactly 2 seconds. Platform: |
Size: 55296 |
Author:辛文乐 |
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Description: 音频信号的水印设计，以音频信号为载体，将秘密信号嵌入载体音频信号当中，
实现音频信号的水印。采用变换域小波变换（DWT）的技术，将音频信号进行小波变换，提取出低频分量，然后将水印嵌入到音频信号的低频当中。实验当中先在MATLAB 上面进行了仿真实验，并且通过加入噪声以及滤波等进行干扰以此检测了算法的透明性和健壮性，然后利用C 语言进行了测试，最后经
过一些修改，例如加入定时器以及进行中断的处理和加入缓冲在DSP 板子上实现了加入水印的音频声音的播放。-Audio signal watermark design to audio signal as the carrier, the carrier signal is embedded in the audio signal.
Realize audio signal watermark. The transform domain wavelet transform (DWT) technology, the audio signal wavelet transform to extract the low frequency component, and then the watermark is embedded in the audio signal of low frequency. Experiments on first in MATLAB, the simulation experiment and by adding noise and filter and so on interference to test the algorithm the transparency and robustness, and by using the C language were tested, and the
Some modification, such as join timer and interrupt handling and join buffer in DSP board to add watermark audio sound broadcast.
Platform: |
Size: 300032 |
Author:江晨城 |
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Description: 水声通信面临的最困难的问题是多途干扰,其中自多途引起接收信号的幅度衰落,互多途引起接收信号的码间干扰,再加上海洋环境的高噪声背景、低的载波频率、极为有限的带宽以及传输条件的时间—空间—频率变化特性,使得通信过程十分困难。此外，水声通信试验的成本高，难度大，也为水声通信研究带来挑战。
本软件对水声信道的仿真研究很有帮助，可以产生声线图，冲激响应，声速图等仿真文件，结合Matlab画图工具绘制图像，对水声信道的模拟仿真很有帮助。-The most difficult problem faced by underwater acoustic communication is multi-path interference, which since multipath fading caused by the magnitude of the received signal, and mutual inter-symbol interference caused by multipath signal reception, plus the marine environment of high background noise, low carrier frequency , very limited bandwidth and transmission conditions of time- space- frequency characteristic such that the communication process is very difficult. In addition, the high cost of underwater acoustic communication experiment, difficult, and challenges for the study of underwater acoustic communication. This software is useful for simulation study of underwater acoustic channel can produce sound chart, impulse response, sound velocity diagrams simulation files, combined with Matlab drawing tools to draw the image of underwater acoustic channel simulation helpful. Platform: |
Size: 415744 |
Author:苏羽 |
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Search - interference in sound