標題: 優先權式頻道借用方法
Channel Borrowing with Priority
作者: 劉志偉
Liu, Chih-Wei
張明峰, 黃書淵
Ming-Feng Chang, Shu-Yuen Huang
資訊科學與工程研究所
關鍵字: 頻道借用;Channel Borrowing
公開日期: 1996
摘要: 由於行動通訊需求的快速成長,以及其有限的無線電波頻道,因此在行動 通訊與計算系統中頻道資源的有效管理愈來愈重要。本論文提出優先權式 頻道借用的方法,以事先排定借用頻道的方向和優先順序,確保頻道的借 用不會違反重複使用的規定,而且利用借用頻道的方式降低系統拒絕服務 的機率。配合使用three states方法,以事先的通知避免不必要的借用詢 問信號,即用較少的控制信號的通知來減少不必要的大量詢問借用頻道的 信號,可以降低在有線網路上控制信號量。再使用buffer channels方法 ,以暫不歸還頻道的方式避免經常性的借還行為,也就可以減少在借還頻 道時產生的大量控制信號。除了頻道分配問題的理論探討外,頻道管理相 關演算法包含頻道使用,與頻道釋放;頻道借用,與頻道出借;借用頻道 歸還,與出借頻道回收等程序。最後我們利用計算機模擬的方式,在平均 和不平均分布的系統通訊量的情況下,比較我們提出的方法在系統拒絕服 務的機率上,接近借用頻道最好的方法BDCL,而再比較所需傳送的控制信 號量,我們提出的方法則有非常好的效果,甚至可以減少一半的控制信號 量。模擬評估之結果可應用在實際個人通訊系統作為改善的依據。 Due to the increasing demand for mobile communication service and the limited radio spectrum allocated to this service, the problem of channel assignment is becoming even more important in mobile communication /computation systems. In this thesis, we investigate a channel assignment scheme based on channel borrowing technique. The channel borrowing is carried out in a fixed sequence in accordance with a channel ordering as well as a priority ordering among the cells. This priority-based channel borrowing scheme effectively reduces communication overhead at the cost of minor increasing in blocking probability. Two improvements are also designed to further reduce the communication overhead. One approach defines the relationship between the owner cells of a channel and its possible borrower cells in terms of three states, such that the communication signals between the cells can be reduced in two out of the three states. The other approach lets the borrower cell buffer a small number of the borrowing channels so that the channel will not be returned and later be borrowed again. Computer simulations are used to evaluate the performance of our schemes in terms of blocking probability and communication overhead.
URI: http://140.113.39.130/cdrfb3/record/nctu/#NT850392028
http://hdl.handle.net/11536/61776
Appears in Collections:Thesis