近年來無線網路的蓬勃發展，日常生活中隨處可見的行動裝置也能夠使用無線網路進行資料的傳輸，下一代無線區域網路標802.11ax 也在2014年開始建置，其目標相較於前一代無線區域網路標準提升四倍的傳輸效能，所以未來我們勢必要使用全雙工(Full duplex)技術來因應未來對傳輸效能的要求。當使用全雙工技術時，會產生內部節點干擾問題及隱藏接收者問題，為了避免上述之問題，本論文設計具電量控制之無干擾全雙工媒介存取控制協定，透過分析干擾範圍與傳輸範圍來整理出傳輸能量對其他節點干擾影響之關係性，讓節點能完全避免內部節點干擾問題及隱藏接收者問題，大幅增加使用全雙工技術時之傳輸效能。

Recently, IEE 802.11ax task group has started to develop a new standard for next generation wireless local area networks (WLANs) since 2014. One of goals is four times throughput improvement compared with IEEE 802.11ac. Thus, the researchers focus on full duplex (FD) communications to achieve improvement of throughput. However, there are Inter-Node Interference (INI) and Hidden Receiver Problem (HRP) in FD communications, which cause decrement of throughput. The paper analyzes the relationships among the transmission range, and interference range in case that FD is adopted and proposes an Interference Free Full Duplex with Power Control (IFFD) MAC protocol to avoid interference for next generation WLANs. IFFD cannot only prevent INI and HRP problems but also can increase network performance. Simulation results show that IFFD outperforms against other protocols in packet error rate and network throughput.

Contents
1.	Introduction	1
1.1 Motivation	3
1.2 Organization	4
2.	Preliminaries	6
2.1 The overview of Full Duplex in WLANs	6
2.1.1 Interference Problem in FD	8
2.2. Related works	12
3.	Problem Statements	17
3.1 Hidden Receiver Problem (HRP)	17
3.2 Analysis	18
4.	Interference Free Full Duplex MAC with Power Control (IFFD)	22
4.1 The concept of IFFD	22
4.2 The analysis of IFFD	25
4.3 The operation process of IFFD	26
4.3.1 The situation of Hidden Receiver Problem	26
4.3.2 The situation of Inter-Node Interference	28
4.3.3 IFFD in AFD	30
4.3.4 IFFD in SFD	32
4.4 DATA transmission in IFFD	33
5.	Simulation	37
6.	Conclusion	41
Bibliography	42
Appendix	45

List of Figures
Figure. 1. Full duplex communications	2
Figure. 2. Transmission modes in FD	7
Figure. 3. STA-initialed Full Duplex (SFD)	8
Figure. 4. AP-initialed Full Duplex (AFD)	8
Figure. 5. Self-Interference	10
Figure. 6. INI in SFD	11
Figure. 7. INI in AFD	11
Figure. 8. A-Duplex MAC	13
Figure. 9. A-Duplex MAC	13
Figure. 10. PoCMAC	14
Figure. 11. FuPlex MAC	15
Figure. 12. FuPlex MAC	16
Figure. 13. Hidden Receiver Problem (HRP)	18
Figure. 14. Transmission Range	19
Figure. 15. Interference Range	19
Figure. 16. HRP with TR and IR	21
Figure. 17. Basic idea of IFFD	24
Figure. 18. Suitable transmission power	24
Figure. 19. The situation of Hidden Receiver Problem	27
Figure. 20. IFFD in Hidden Receiver Problem	28
Figure. 21. The situation of normal Inter-Node Interference	29
Figure. 22. IFFD in INI	29
Figure. 23. The summary of IFFD	30
Figure. 24. IFFD in AFD	31
Figure. 25. Scenario of SFD	32
Figure. 26. The structure of CTS	33
Figure. 27. Operation example of IFFD in SFD	33
Figure. 28. ACK time out problem	35
Figure. 29. Solution of ACK time out problem	36
Figure. 30. The comparisons of throughput	38
Figure. 31. The comparisons of packet error rate of downlink	39
Figure. 32. The overall of packet error rate	40

List of Tables
Table 1: Simulation parameters	37

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