具分散式子集選擇演算法的功率控制研究

一個功率控制無線網絡的容量可以被改變，是由於使用者的移動性、衰減和遮蔽效應，其結果造成所有的用戶在無線網路中不能被保證其服務品質的好壞。在本文中，我們提出了一個基於功率控制的兩相位分佈子集選擇演算法和結合排程演算法，用這些演算法來識別無線用戶的子集並保證無線用戶的服務品質為佳。兩相位分佈的子集選擇演算法，其運作分成兩個階段。第一階段是先找出基本的可行鏈接和未定鏈接，接著在第二階段，嘗試擴大基本可行鏈接的數量，其擴大數量的方法是判斷未定鏈接是否有機會成為可行鏈接。另一種方法則是結合排程演算法，是將每個鏈接各別跑流程圖，然後判斷是否為有效方案(Valid Scenario)，再判斷是否符合可接受方案(Admissible Scenario)，最後統計全部的可行鏈接數目。最後透過模擬結果，我們評估了這些方案在性能方面的平均可行鏈接數和平均執行時間。

關鍵字

子集選擇；功率控制；無線網路；服務品質；連接接納控制

並列摘要

The capacity of wireless networks can be changed due to user mobility, fading and shadowing effect, this results in the fact that the quality of service cannot be guaranteed. In this thesis, we study the two-phase power control based subset selection algorithms and the joint scheduling algorithm, with these algorithms, we can identify a subset of wireless users and can obtain better quality of service for wireless users. The operations of two phase distribution subset selection algorithm are divided into two stages. The first stage aims to identify the basic feasible links and undetermined links, and the second stage aims to increase the number of feasible links by possibly letting the undetermined links become feasible links. On the other hand, the distributed scheduling algorithm aims to combine scheduling with power control to increase the number of feasible links. Simulation results show that the one-by-one merge algorithm results in the largest average number of feasible links among all studied algorithms.

並列關鍵字

Subset selection ； power control ； connection admission control

參考文獻

[1] Chun-Chia Chen, Duan-Shin Lee,” A Distributed Subset Selection Algorithm for a Set of Mobile Links with Power Control” IEEE TRANSACTIONS ON WIRELESS COMMUNICATIONS, VOL. 7, NO. 6, JUNE 2008

Google Scholar

[2] T. ElBatt and A. Ephremides, “Joint scheduling and power control for wireless ad hoc networks,” IEEE Trans. Wireless Commun., vol. 3, no. 1, pp. 74–85, Jan. 2004