中結合頻道借用與細胞扇形化解決鬧區細胞話務負載之研究

Abstract

中，不可預期的話務負載增加可能會造成部份細胞話務擁擠。 畢X借用頻 道與細胞扇形化的方法，其可有效地解決不可預期話務負載增加的問題。 針對系統可能發生的情形，我們分析單一施贈細胞與單一鬧區細胞、多個 施贈細胞與單一鬧區細胞、單一施贈細胞與多個鬧區細胞等系統，並且證 明我們的方法是較佳結合頻道借用與細胞扇形化方法。此方法可有效的增 加幹線的效率及頻率使用率。此外，還可以降低鬧區細胞的阻塞率。若每 個細胞有 60 頻道和要求阻塞率不可超出 0.01，則最大的話務負載約可 到 47 歐蘭。在先前所提出的研究中 [7]，假設鬧區細胞的話務負載是 66 歐蘭，則需向施贈細胞借 21 個頻道，但是施贈細胞的話務負載必須 降至 28.13 歐蘭，減少了 18.87 歐蘭。不過，在我們的方法裡施贈細胞 與受干擾細胞最大話務負載可為 42.63 及 45.87 歐蘭，話務容量只減少 非常小。 Undesirable growth of traffic may develop in various cells toaffic congestions in a cellular mobile systems. In this thesis, weine channel borrowing with cell sectoring to effectively handle unexpected growth of traffic. We analyze single donor cell and single hot-spot cell, multiple donor cells and single hot-spot cell, and single donor multiple hot- spot cells systems. The proposed scheme is effective for increasing the trunking efficiency and frequency utilization. It can reduce the probability of heavily loaded cells, i.e.,hot- spot cells. If each cell is allocated 60 channels and blocking probability requirement is 1 percent, then the maximal traffic load is 47 In a previous study [7], if the hot-spot has a load of 66 Erlangs, then it needs to borrow 21 channels from the donor cell. But, the load of the donor cell cannotlangs. The reduced load is 18.87 Erlangs in the donor cell. On the other hand, for our scheme the maximal traffic loads of cell and the interfered cells is 42.63 and 45.87 Erlangs, The losses in traffic capacity of the donor cell and thes are little.