臺灣博碩士論文加值系統

窄頻物聯網(NB-IoT)是由3GPP(Third Generation Partnership Project)所提出的一種新的窄頻無線電技術，用於提供低電耗廣域的物聯網。在窄頻物聯網系統裡，連結的物聯網裝置數量相當大量且每個裝置的成本很低，並有很長的電池壽命，能運作維持長達十年。但窄頻物聯網的頻寬很小，所以如何有效率的利用資源去達到大量連接(massive connection)是值得去探討的。窄頻物聯網中的窄頻下行控制通道(NPDCCH; Narrowband Physical Downlink Control Channel)和窄頻下行共享通道(NPDSCH; Narrowband Physical Downlink Shared Channel)將透過延長時間來傳送資料，此兩者的長度是一個下行控制通道週期並透過R_max和G這兩個數值來決定，本篇碩論發現，該週期的長度對於窄頻物聯網的無線資源利用率有很大的影響。本篇論文將詳細介紹窄頻物聯網無線電接入策略的細節，我們的目標是最小化子訊框(subframe)的個數來滿足每個裝置需接收的資料需求，此論文提出一個有效的調適性下行控制通道周期演算法來減少資源的浪費。。與其一個暴力演算法和一個固定周期方法比較之下最後模擬結果顯示我們提出的方法可以有效的減少無線資源的損耗。

The narrowband Internet of Things (NB-IoT) is a new narrowband radio technology defined by the 3GPP (Third Generation Partnership Project) for low power networks. In a NB-IoT system, the connected devices are quite large. Each low cost device has a long battery life and can operate for up to ten years. However, the bandwidth of the narrow-band Internet of Things is small. How to efficiently use resources to achieve a massive connection is worthily explored. The NPDCCH (Narrowband Physical Downlink Control Channel) and the NPDSCH (Narrowband Physical Downlink Shared Channel) in the narrow-band Internet of Things will be lengthened to transmit data. The lengths of NPDCCH and NPDSCH are a NPDCCH period (PP) and are determined by two parameters, R_max and G. This thesis observes that the NPDCCH period has significant impacts on the radio resource utilization. This thesis describes the radio access strategy, and our objective is to minimize the consumed subframes to meet the data requirement constraint of each NB-IoT device. Then, this thesis proposes a downlink PP adaptation algorithm to reduce the radio resource consumption. . Compared with a brute-force algorithm and a fixed algorithm, the simulation results show that the proposed algorithm is effective in reducing the radio resource consumption.

目錄 v
圖目錄 vii
表目錄 viii
1 導論 1
1.1　前言 1
1.2　動機 2
1.3　文獻 3
1.4　貢獻 3
1.5　全文架構 3

2 系統模型 4
2.1　背景介紹 4
2.2　問題描述 7

3 窄頻物聯網之調適性下行控制通道周期分配 9
4 效能評估 18
4.1　實驗參數 18
4.2　實驗結果 19
5 結論與未來方向 27
6 參考文獻 28

[1] C. Yu, L. Yu, Y. Wu, Y. He, and Q. Lu, “Uplink Scheduling and Link Adaptation for Narrowband Internet of Things Systems,” IEEE Access, vol. 5, pp. 1724–1734, 2017.
[2] 3GPP, ”Radio Resource Control (RRC); Protocol specification,” 3GPP TS 36.331 V13.2.0, June 2016.
[3] S. Barros , J. Bazzo, O. d. R. Pereira, D. Carrillo, and J. Seki, “Evolution of Long Term Narrowband-IoT”, IEEE Access, vol. 5, Aug , 2017
[4] 3GPP, “3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer modulation”, 3GPP TS 36.213 V14.3.0, 2017.
[5] R. Boisguene, S.-C. Tsengy, C.-W. Huang, and P. Lin, “A Survey on NB-IoT Downlink Scheduling: Issues and Potential Solutions,” International Wireless Communications and Mobile Computing Conference (IWCMC), 2017.
[6] Y. J. Yu and S. C. Tseng, “Downlink Scheduling for Narrowband Internet of Things (NB-IoT) Systems”, IEEE Vehicular Technology Conference (VTC Spring), 2018
[7] 3GPP, ”Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures” 3GPP TS 36.213 V14.3.0, 2017
[8] R. Ratasuk, N. Mangalvedhe, Z. Xiong, M. Robert, and D. Bhatoolaul,” Enhancements of Narrowband IoT in 3GPP Rel-14 and Rel-15”, 2017 IEEE Conference on Standards for Communications and Networking (CSCN), Oct 2017.
[9] 3GPP, “Radio resource control (RRC); Protocol specification (Release 13),” 3GPP TS 36.331 v13.2.0 Section 6.7.2, Jun. 2016.