範例：量子化信號

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範例：量子化信號

使用 quantize 函數量子化類比信號。以多個平均間隔的不連續等級表示信號，即可完成。

量子化雙曲線信號

1. 定義量化位準數。

2. 定義表示雙曲線信號的值域及方程式。

3. 計算各量子化能階的高度。

4. 量子化信號。

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• 量子化能階的時間長度不必一致，原始信號也不必一定要穿越量子化信號的中點。

• 數位信號處理技術的多數硬體實行，都是從類比至數位的轉換器晶片開始，類比信號會在此晶片上量子化。若輸入信號的頻率比取樣率逆轉慢許多，則提供上述的選擇量子化能階方法，量子化會產生原始類比信號真正的近似值。否則，必須使用信號處理技術恢復信號的結構。

濾波及重新建構量子化信號

1. 採用已量子化為 8 能階的正弦曲線信號。

2. 量子化信號。

3. 繪製原始與量子化的信號。

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4. 使用具有 15 個係數且以漢寧窗設計的低通 FIR 濾波器 (第三個引數低於集合窗) 及實驗方法，求解正確的截止頻率。

截止頻率設為 0.12，取窗設為 4。

5. 使用 response 函數濾波量子化的信號。

6. 繪製濾波過的重新建構 s 與原始信號 a。

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量子化陣列

量子化儲存在 2D 陣列中分為 5 個能階的高斯光點，並以灰階色塊圖顯示兩個陣列，以說明量子化的視覺效果。

1. 定義量子化能階數。