範例︰複數函數的 DFT

函數 > 轉換與濾波器 > 範例︰複數函數的 DFT

範例︰複數函數的 DFT

使用 dft 與 idft 函數計算複數或實數的傅立葉轉換或傅立葉逆轉換。

1. 建立若干具有 N 個數據點的模仿複數數據。

按一下以複製此運算式

按一下以複製此運算式

2. 定義取樣間距。

按一下以複製此運算式

按一下以複製此運算式

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按一下以複製此運算式

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        <id labels="CONSTANT" xml:space="preserve" xml:lang="zh_TW" label-is-contextual="true">π</id>
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3. 使用 exp 函數定義以下信號。

按一下以複製此運算式

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            <imag symbol="i" xml:lang="zh_TW">1</imag>
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4. 定義取樣頻率及對應至已轉換向量內第 n 項的頻率。

按一下以複製此運算式

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按一下以複製此運算式

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5. 套用 dft 函數，將數據轉換成頻域。

按一下以複製此運算式

6. 將陣列 D 的元素量值儲存到新的陣列。

按一下以複製此運算式

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7. 使用 match 與 max 函數計算尖峰振幅和頻率。

按一下以複製此運算式

按一下以複製此運算式

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按一下以複製此運算式

8. 將 DFT 的量值以頻率函數圖表表示。

按一下以複製此運算式

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9. 顯示對應至 ω0/2π 之尖峰值的頻率。

按一下以複製此運算式

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10. 使用 idft 函數顯示信號的 DFT IDFT 傳回信號本身。

按一下以複製此運算式

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