本篇論文提出一個基於馬克勞林級數的低成本修正型離散餘弦轉換電路架構。大多數的音訊編碼標準中，使用修正型離散餘弦轉換作為把音訊從時域轉換至頻域的工具，在修正型離散餘弦轉換中使用到大量的三角函數係數，而一般的電路架構使用查表方式來趨近於三角函數，但是查表的方法在MPEG AAC裡將會造成面積過大以及設計不夠彈性的缺點。因此我們在此採用馬克勞林級數來實現一個特殊電路模組用以計算三角函數，而且同時運用了三角函數的對稱性與週期性來降低電路的複雜度。結果證實我們所設計的架構跟其他架構相比可以大大節省晶片面積。
這個電路是用台灣積體電路製造股份有限公司所提供的0.18μm互補式金氧半製程來進行合成，它的整體面積大約為6040個邏輯閘數，並且最大可以操作在58.8 MHz的時脈頻率，所以此設計適合應用於低成本的多媒體系統。

Most of current audio coding standards use the modified discrete cosine transform (MDCT) to transform an audio sequence from time domain to frequency domain. This thesis presents a low-cost MDCT architecture based on Maclaurin series. Most architectures used lookup table to approach trigonometric function, but the lookup table in MPEG AAC will cause the design large and inflexible. Therefore, we adopt Maclaurin series to design the computation circuit and apply the symmetry and periodic identities of trigonometric function to reduce the circuit complexity. It results that our proposed architecture can be implemented with less area than other MDCT architectures.
0.18 μm TSMC cell library technology is used to synthesize the architecture. The proposed architecture takes about 6040 gates with maximum operation frequency of 58.8 MHz. Therefore, it is suitable for low-cost multimedia applications.

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