不同傳輸功率下機器通訊網路之最小能量損耗中繼站選擇

Abstract

在機器通訊中，群組傳輸的目的是幫助傳輸系統降低能量消耗、資源分配及提升服務品質。我們可以利用分群演算法將系統中的機器分群並找到適合的協調者與基地台做溝通以實現群組傳輸系統。之前提出的演算法是根據複雜度較低的K-means分群演算法去做修改，不過在這些修改的過的演算法中讓分群的結果不盡理想，因為群組數量是固定使得每個機器設備並不會找到最佳的協調者，以達到最佳的系統能量消耗。另外，這樣的群組演算法中並沒有考慮到機器設備會有不同發射功率的情況下，並不會達到最佳的系統能量消耗。在這篇論文中，由於機器設備都是裝載電池的，我們考慮到機器設備會有不同的傳輸功率，因此設計出一種中繼站選擇演算法目的是為每個機器設備找出適合它們的中繼站，達到最低系統能量消耗。我們主要考慮的是機器系統能量消耗最小情況，並提出圓環中繼站選擇演算法來解決之前的分組問題並降低能量的消耗。

In the machine to machine communication, the group based system is use of energy saving, resource allocation and quality of service. To implement a group based system, we group the machine devices together and communicate with base station by grouping algorithm and coordinator selection scheme. These modified algorithms are based on K-means, which is a low complexity algorithm. However, the modified algorithms have some existing problems; these problems will make the algorithm converge with the inefficient grouping result due to set amount of groups and without considering the different power level, because a machine device have not discovered a best coordinator to increase energy consumption in the system. In this thesis, since the machine devices are battery equipped with different power level, we focus on the uplink energy consumption of the system and propose an algorithm to solve the problems. Consequently, we also design circle pattern coordinator selection algorithm, which proposes to find a best coordinator for each machine devices to minimize energy consumption in the system.