Cognitive radio is a promising technique to improving the utilization of the spectrum in wireless communication system. The cognitive radio controls that the interference caused by the cognitive users is below the interference temperature of the primary user. In this thesis, we apply the minority game and the Cournot game methods to the power control of multiple cognitive users. The minority game uses the interference of the primary user which is caused by the major part of cognitive users. If the interference is large than the interference temperature, then the major part of cognitive users transmit less power. The Cournot game sets the pricing function for each cognitive user. Each cognitive user adjusts their transmitting power to maximize the pricing function. If the Nash equilibrium exists, then the Cournot game can be solved. Two methods both can control the interference caused by the cognitive users below the interference temperature of the primary user. The simulation results show that the performance of Cournot game method is better than the performance of minority game method in different environment, but the minority game method can be realized based on less channel information than the Cournot game method.

感知無線電技術(Cognitive radio)在現今的無線通訊環境下，是個促進頻帶使用效率非常有前瞻性的方法。最基本的感知無線電技術是有智慧地偵測並確認哪一個通訊頻帶主要使用者正在使用，而將次要使用者轉換到沒有被佔用的頻帶上。而另外一種感知無線電技術則是將使用者對主要使用者的干擾降低到主要使用者的規範。而本篇論文是建立於對主要使用者的干擾符合主要使用者的規範，而應用了賽局理論的方法來實現對於多個次要使用者的功率控制。
本篇論文討論了兩種賽局理論的模型來應用在功率控制。第一個是寡勝賽局(minority game),而第二個是古諾賽局(Cournot game)。寡勝賽局應用到功率控制上主要是利用多個次要使用者對於主要使用者的干擾，取決於功率打得較多的次要使用者，所以可以讓寡勝賽局成立。如果干擾過多則功率打得較多的必須減少傳輸功率，如果干擾比較少則功率打得較多的可以繼續增加傳輸功率。而古諾賽局應用到功率控制上則是為每個次要使用者制定一個利潤的函數，每個次要使用者去追求這個利潤的最大值，若納許均衡(Nash equilibrium)存在則這個古諾賽局有解。這兩個賽局理論均能有效的控制對於主要使用者的干擾符合主要使用者的規範。模擬的結果顯示古諾賽局有著較好的成果，不論在不同的環境或是有多少次要使用者均是如此。而寡勝賽局雖然成果較差，但是對於通道的資訊需求量卻是較低的。

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