為了提高頻譜效率，給二級認知用戶提供更多的頻譜接入機會，同時保證用戶的服務質量(QoS)，該文章基于傳統的頻率復用方法在多小區正交頻分多址接入(OFDMA)系統的場景中提出了一種動態頻譜分配(DSA)算法。該算法使得持有頻譜執照者在認知無線電環境中在很大的區域內釋放頻譜給其他的二級市場，還建立了一個分配花費矩陣，使得小區間的干擾達到最小，保證了用戶的服務質量(QoS)。與傳統的頻率復用方法相比，該算法有更好的頻譜效率，并給二級市場的使用創造了更多的機會。

　　Abstract:

　　To improve the spectral efficiency，to offer more opportunity for secondary usage and to guararlee the quality of service(QoS) of the licensed users，This paper proposed a dynamic spectrum assignment(DSA) algorithms for multicell orthogonal frequency division multiple access(OFDMA) scenarios based on conventional frequency reuse strategies. According to the proposed algorithms，spectrum license holders can release spectrum bands in large geographical areas to other secondary markets in a cognitive radio environment.And it also built a cost assigning matrix and made the disturb between cells to the least，which guaranteed quality of service(QoS) of the licensed users in the system.Comparing with the traditional frequency reuse strategies，this algorithm has better spectral efficiency and gives more opportunities for secondary usage.