臺灣博碩士論文加值系統

隨著無線通訊設備以及頻譜需求的快速增加，目前的授權頻譜資源越來越不足以滿足接下來通訊系統所需的數據率。
因此，將 LTE 與 5G 赫茲的非授權頻譜透過載波聚合的方式來傳輸的技術被提出，使得原本在授權頻譜上的資料流量能夠釋放到非授權頻譜上，以達到舒緩日趨壅塞的授權頻譜的目的，而此技術也被稱為授權輔助 接取LTE或是免執照LTE。
然而，我們認為目前存在的共存機制，在某些情況下會限制LTE以及Wi -Fi的傳輸效率，仍有其可以改善的空間。因此,本篇論文提出了透過小區呼吸來使得LTE以及Wi-Fi能夠共同傳輸的機制。最後，分析LTE以及Wi-Fi的覆蓋區域的效能表現。

As the rapid growth of wireless devices and enormous demand of spectrum recourse, there will be fewer and fewer licensed spectrum can be used. As the result, LTE carrier aggregation with 5 GHz unlicensed spectrum has been proposed to offload the traffic in licensed spectrum, also known as LAA and LTE-U. However, we think the coexistence algorithm of LAA and LTE-U will limit the transmission of LTE and Wi-Fi potentially. We proposed the mechanism that allow LTE and Wi-Fi transmit simultaneously, by cell breathing and positioning. At last, analysis the performance of LTE''s and Wi-Fi''s coverage.

中文摘要 i
Abstract ii
Contents iii
List of Figures vi
1 Introduction 1
1.1 Overview of LAA and LTE-U . . . . . . . . . . . . . . . . . . . . . . . . . 1
1.2 Overview of Cell Coverage . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.3 Literature Survey . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
1.4 Motivation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
1.5 Related Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2 Single LTE Small Cell with SingleWi-Fi Access Point 8
2.1 System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
2.2 Propagation Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
2.3 Modeling Channel Access for Wi-Fi . . . . . . . . . . . . . . . . . . . . . . 10
2.4 Coverage Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
2.5 Definition of Performance Metrics . . . . . . . . . . . . . . . . . . . . . . . 12
2.6 Illustration of Cell Coverage and CSR and CGR in Each Scenario . . . . . . 14
2.6.1 Adjust transmission power when fixing position . . . . . . . . . . . . 14
2.6.2 Adjust position when fixing transmission power . . . . . . . . . . . . 14
2.6.3 Comparison of adjusting the trasmission power at different position . 15
3 Single LTE Small Cell with twoWi-Fi Access Point 21
3.1 System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
3.2 Definition of Performance Metrics . . . . . . . . . . . . . . . . . . . . . . . 22
3.2.1 SINR of Wi-Fi Station . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.2.2 SINR of LTE UE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.3 Illustration of Cell Coverage and CSR and CGR in Each Scenario . . . . . . 23
3.3.1 Adjust transmission power when fixing position . . . . . . . . . . . . 23
3.3.2 Adjust position when fixing transmission power . . . . . . . . . . . . 23
3.3.3 Comparison of adjusting the trasmission power at different position . 23
4 Single LTE Small Cell with threeWi-Fi Access Point 29
4.1 System Model . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 29
4.2 Definition of Performance Metrics . . . . . . . . . . . . . . . . . . . . . . . 30
4.2.1 SINR of Wi-Fi Station . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.2.2 SINR of LTE UE . . . . . . . . . . . . . . . . . . . . . . . . . . . . 30
4.3 Illustration of Cell Coverage and CSR and CGR in Each Scenario . . . . . . 31
4.3.1 Adjust transmission power when fixing position . . . . . . . . . . . . 31
4.3.2 Adjust position when fixing transmission power . . . . . . . . . . . . 31
4.3.3 Comparison of adjusting the trasmission power at different position . 31
5 Dynamic Power Allocation 37
5.1 Problem Formulation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37
5.2 Adjust Transmission Power of LTE Small Cell . . . . . . . . . . . . . . . . . 38
5.3 Adjust Position of LTE Small Cell . . . . . . . . . . . . . . . . . . . . . . . 40
6 Comparison of Different Scenario and Simulation Result 42
6.1 single LTE small cell with single Wi-Fi access point . . . . . . . . . . . . . . 43
6.2 single LTE small cell with two Wi-Fi access point . . . . . . . . . . . . . . . 44
6.3 single LTE small cell with three Wi-Fi access point . . . . . . . . . . . . . . 46
6.4 The Calculate of Throughput . . . . . . . . . . . . . . . . . . . . . . . . . . 47
7 Conclusion 48
8 Reference 49

[1] 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Study on Licensed-Assisted Access to Unlicensed Spectrum (3GPP TR 36.889 V13.0.0)
[2] Broadband Radio Access Networks (BRAN); 5 GHz high performance RLAN; Harmonized EN covering the essential requirements of article 3.2 of the R&TTE Directive (ETSIEN 301 893 V1.7.1)
[3] “LTE-U Technology and Coexistence”, Qualcomm (2015-05)
[4] H. Q. Nguyen, F. Baccelli and D. Kofman, "A Stochastic Geometry Analysis of Dense IEEE 802.11 Networks," IEEE INFOCOM 2007 - 26th IEEE International Conference on Computer Communications, Anchorage, AK, 2007
[5]Y. Li, J. Zheng and Q. Li, "Enhanced listen-before-talk scheme for frequency reuse of licensed-assisted access using LTE," 2015 IEEE 26th Annual International Symposium on Personal, Indoor, and Mobile Radio Communications (PIMRC), Hong Kong, 2015, pp. 1918-1923.
[6]Y. Li, M. Zhang, Y. Yang and X. Wang, "Fair Downlink Traffic Management for Hybrid LAA-LTE/Wi-Fi Networks," 2016 IEEE Global Communications Conference (GLOBECOM), Washington, DC, 2016, pp. 1-6.
[7]Fanrong Hao, Chang Yongyu, Hongdou Li, Jian Zhang and Wei Quan, "Contention window size adaptation algorithm for LAA-LTE in unlicensed band," 2016 International Symposium on Wireless Communication Systems (ISWCS), Poznan, 2016, pp. 476-480.
[8]O. El-Samadisy, M. Khedr and A. El-Helw, "Performance Evaluation of MAC for IEEE 802.11 and LAA LTE," 2016 International Conference on Computational Science and Computational Intelligence (CSCI), Las Vegas, NV, 2016, pp. 923-928.
[9]Y. Gao, X. Chu and J. Zhang, "Performance Analysis of LAA and WiFi Coexistence in Unlicensed Spectrum Based on Markov Chain," 2016 IEEE Global Communications Conference (GLOBECOM), Washington, DC, 2016, pp. 1-6.
[10]Y. Li, F. Baccelli, J. G. Andrews, T. D. Novlan and J. C. Zhang, "Modeling and Analyzing the Coexistence ofWi-Fi and LTE in Unlicensed Spectrum," in IEEE Transactions on Wireless Communications, vol. 15, no. 9, pp. 6310-6326, Sept. 2016.
[11]A. Bezzina, M. Ayari, R. Langar and L. A. Saidane, "A fair cluster-based resource and power allocation scheme for two-tier LTE femtocell networks," 2016 Global Information Infrastructure and Networking Symposium (GIIS), Porto, 2016, pp. 1-6.
[12] 3rd Generation Partnership Project; Technical Specification Group Radio Access Network; Evolved Universal Terrestrial Radio Access (E-UTRA); Further advancements for E-UTRA physical layer aspects (3GPP TR 36.814 V9.0.0)
[13] Harri Holma,Antti Toskala,Jussi Reunanen,” LTE Small Cell Optimization 3GPP Evolution to Release 13”