隨著無線通訊技術的快速成長,傳輸頻帶的需求也日益增加。根據量測,大部分的頻帶在特定時間裡都是沒有使用的。為了提升頻譜的使用效率,感知無線電的概念被提出,如何在不干擾主要使用者的前提下偵測到未使用的頻帶,使次要使用者充分利用頻段,已經成為一個重要的研究議題。 快速且準確的頻譜偵測是實現感知無線電網路的基本要求。在本文中,我們在不需要偵測通道的資訊,也不限制偵測的訊號種類的前提下,根據能量偵測的方法分析研究了幾種同時偵測多條頻帶的快速頻譜偵測演算法。接著本篇論文中提出一利用最大正差值(maximum and positive peak algorithm, MPP) 檢測的演算法,在犧牲些微效能的情況下,可節省大量的偵測時間。根據實驗模擬結果,我們提出的演算法,其效能與快速偵測的優點皆能符合實現感知無線電網路的基本需求。With fast growing of the wireless communication technology, radio wave is an important resource in transmitting signal. However, according to several measurements, large amounts of spectrum are unused at the particular moment. Due to the electromagnetic radio spectrum is a natural resource, the appropriate spectrum usage is an important issue. For the great utilization of spectrum, how to find a spectrum hole to use has becoming an interesting issue in cognitive radios. To implement any cognitive radios (CR) network, a fundamental functional requirement is the availability of a multitude of fast and accurate spectrum sensing technique. Various fast spectrum sensing algorithms which require no information about the sensed channel and the primary signal structure in multiple-channel scenarios would be investigated. In this study, a fast censoring multi-tone energy detection algorithm called maximum and positive peak algorithm (MPP) is proposed. The performance of proposed algorithm is compared with several censoring algorithms by computer simulations and their computational complexities. Numerical results show that the proposed algorithm does provide satisfactory performance instantaneously.