QT GUI 频率接收器 GNU Radio Windows 上的问题
我尝试通过将噪声源配置中的幅度值设置为 1 来生成标准偏差为 1 的高斯噪声信号。
当我尝试使用 QT GUI 频率接收器显示它时,我最初预计生成的 PSD 会围绕所有频率点均为 0 dB。然而,我发现 QT GUI 频率接收器上显示的 PSD 在所有频率点上波动在 -40 dB(而不是 0 dB)左右。
从信号处理理论的角度来看,这个结果显然是不正确的。
我的应用程序中是否存在我不知道的错误?
我在 Windows 10 上使用 GNU Radio 应用程序 v3.8.2.0-57-gd71cd177 (Python 3.9.0)。
I tried to generate a Gaussian noise signal having a standard deviation of 1 by setting the amplitude value in the noise source configuration to 1.
When I tried to display it using the QT GUI Frequency Sink, I initially expected that the resulting PSD would fluctuate around 0 dB across all frequency points. However, I have found that the PSD displayed at QT GUI Frequency Sink fluctuates around -40 dB (instead of 0 dB) over all frequency points.
From the signal processing theory's point of view, this result is clearly incorrect.
Is there a bug in my app that I don't know?
I am using GNU Radio application v3.8.2.0-57-gd71cd177 (Python 3.9.0) on windows 10.
如果你对这篇内容有疑问,欢迎到本站社区发帖提问 参与讨论,获取更多帮助,或者扫码二维码加入 Web 技术交流群。
绑定邮箱获取回复消息
由于您还没有绑定你的真实邮箱,如果其他用户或者作者回复了您的评论,将不能在第一时间通知您!
发布评论
评论(1)
有两件事:您的期望中有一个错误:
所有功率的总和需要在 1 左右,即 0dB,因为这是功率,因此是方差,因此各个箱需要更低 - 在事实上,FFT 越低,时间越长。
但频率接收器中也存在未记录的缩放,因此如果我们愿意,我们可以将其称为 GNU Radio bug。 GNU Radio 已经意识到这个问题。这个问题不容易解决,因为出现意外行为很糟糕,而且破坏现有应用程序也很糟糕。
Two things: there's a bug in your expectation:
the sum of all powers needs to be around 1, i.e. 0dB, because that's the power and thus the variance, so the individual bins need to be lower - in fact, the lower the longer your FFT is.
But there's also undocumented scaling in the frequency sink, so we can call that a GNU Radio bug, if we want. GNU Radio is aware of the problem. It's not easy to address because it's bad to have unexpected behaviour, but it's also bad to break existing applications.