針對LTE-A系統下考慮通道狀況的多用戶排程之省電演算法

Abstract

3GPP 長期演進技術（Long Term Evolution-Advance，LTE-A）是一種要求更高傳輸速率，更低延遲以及更少封包丟失率的第四代移動通信技術。隨著物聯網（IoT）技術的發展，越來越多的設備會接入互聯網。更多的設備，更高的傳輸速率會帶來更大的耗電量，綠色通信也在近年也成為一個熱門議題。為了降低設備的耗電量，不連續接收（discontinuous reception，DRX）被提出。然而，考慮通道狀況的DRX則經常會被忽略。在這篇論文中，我們提出了考慮通道狀況的多用戶排程之省電演算法（Channel-aware multi-user scheduling，CAMS），其中使用了部分可觀察馬可夫決策過程（partially observable Markov decision process，POMDP）來預測封包的產生。論文包括，不安連續接收週期的選擇，封包預測以及資源分配等幾個部分。最後，我們提出的省電演算法（CAMS）在多用戶情況下明顯降低了設備的耗電量。

The Long Term Evolution Advanced (LTE-A) is one of the fourth generation (4G) technology which requires higher data rate, lower delay time and lower packet loss. Heterogeneous network was introduced into LTE-A to ease the traffic burden. More and more devices will be connected in Internet since the development of IoT. Therefore, green communication becomes a popular issue because higher data rate and more devices and base stations cause an increasing of electricity demand. Discontinuous reception (DRX) mechanism is introduced to save power of mobile devices. However, effect of channel condition on DRX is neglected. In this thesis, we proposed a novel algorithm called channel-aware multi-user scheduling (CAMS) scheme to save power in multi-user situation via DRX mechanism. Partially observable Markov decision process (POMDP) is used to predict the traffic status in our algorithm. This algorithm is composed of several parts which are DRX cycle selection, future packet prediction and resource allocation. With CAMS scheme, we successfully reduce the power consumption of UE in LTE-A system.