本論文計畫一個系統控制陣列聲源來集中聲音，其目的在增加使用者區域之聲音能量，經由控制聲源輸入之訊號來減少其他區域之聲音能量。接著以聲音對比控制理論為基礎，利用Matlab程式得到陣列麥克風之權重函數，並建立控制陣列聲源之實驗及使用Matlab程式模擬於不同聲場邊界與控制方法下之聲場分佈。

　　為了印證此聲音對比控制法，本論文將各種不同參數條件做模擬分析，例如：將能量集中於一點、能量集中於區域、陣列聲源數量、陣列聲源間距與不同發射頻率之比較等；以及在自由聲場與一般聲場環境下，將未受控制聲源與受控制聲源之實驗結果作比較，以驗證本研究之可行性及完成最佳化聲場配置。最後，由一般聲場實驗中得知，聲音響亮區與聲音安靜區有6~11 dB值之差異，由此可知，經由聲音對比控制法可實現於一般聲場之能量集中，預計在未來可有多元化之運用。

In this thesis, a system for focusing sound around the user by using a line array of controlled sources is proposed. To increase acoustic energy only in the “bright zone” where the user is within but to reduce it in the other selected “dark zone” by controlling input signals is the main objective of this study. The program based on acoustic contrast control theory is designed to obtain input weighting coefficients for microphones using Matlab. Experiments with a line array of controlled sources and simulations under Matlab are established in order to observe the distribution of sound field under different boundary and control conditions.

To test this system, a variety of simulation conditions are used, such as: energy focused at a point, energy focused in a region, the number of a line array sources, array element distance, and emission frequency. As for experiment, in the free field and reflected sound field, the uncontrolled and controlled sources are taken to compare results. Based on simulations and experiments, the optimal configurations for controlled sound field are obtained. Finally, from general sound field experiments, the difference of sound pressure level between bright zone and dark zone is 6 ~ 11 dB. Therefore, general sound field energy focusing is realized via acoustic contrast control method and expected to have a diversification of use in the future.

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