基於全雙工中繼器平台實現Wi-Fi通道預約機制於非授權頻譜;Implementation of Wi-Fi Channel Reservation Using Full Duplex Radio Repeater over Unlicensed Spectrum

NCUIR > College of Electrical Engineering & Computer Science > Executive Master of Communication Engineering > Electronic Thesis & Dissertation > Item 987654321/95353

Please use this identifier to cite or link to this item: http://ir.lib.ncu.edu.tw/handle/987654321/95353

Title:	基於全雙工中繼器平台實現Wi-Fi通道預約機制於非授權頻譜;Implementation of Wi-Fi Channel Reservation Using Full Duplex Radio Repeater over Unlicensed Spectrum
Authors:	林冠勳;Lin, Guan-Xun
Contributors:	通訊工程學系在職專班
Keywords:	全雙工無線電 (FDR);自適應濾波器;可程式化邏輯閘陣列;ZC序列;載波頻率偏移;通道預約;Full Duplex Radio;Adaptive Filter;Field Programmable Gate Array;Zadoff-Chu Sequence;Carrier Frequency Offset;Channel Reservation
Date:	2024-07-26
Issue Date:	2024-10-09 16:41:57 (UTC+8)
Publisher:	國立中央大學
Abstract:	第五代行動通訊 (5G) 應用情景其中一項為超低延遲通訊 (ultra-reliable and low latency communications，URLLC)，其特性為低延遲以及高可靠性。若要實現此服務於非授權頻譜 (unlicensed spectrum) 將面臨許多問題，例如來自異質 Wi-Fi網路干擾等。本論文根據先前所提出之非授權頻譜通道預留機制 (channel reservation mechanism，CRM)，利用一台全雙工無線電中繼器 (Full Duplex Radio Repeater，FDRR) 平台於非授權頻譜某一通道持續發出Busy Tone (BT) 以達成通道預約目的，並可同時於該通道上傳輸訊息不受干擾，驗證先前所提出之非授權頻譜通道預留機制之可行性。本論文設計使用多台FDRRs平台模擬第五代行動通訊場景內基地台 (gNB)與用戶設備 (UE)，實現於非授權頻譜之CRM。其原理為gNB與所有UEs同時於一非授權頻段之通道上發送相同長度但是不同根索引之ZC序列作為BT，另外，若一設備欲傳遞資料訊息亦使用不同根索引之 ZC序列傳送。gNB與UEs間透過匹配濾波器 (matched filter) 可有效匹配已知ZC序列進而區別來源設備之訊息，達成數台UEs和gNB同時發射BT時也能同時接收到不同設備之訊息，互不干擾。此時，存取此通道之Wi-Fi設備將因其採用載波偵測多重存取/碰撞避免 (CSMA/CA) 而被所提出之CRM阻擋存取機會，從而實現通道預約。實驗透過 Iperf軟體測試觀察Wi-Fi通道吞吐量驗證是否該通道已被佔用。於設計階段，我們使用Quartus工具編寫Verilog程式，並對FDRR內FPGA編寫程式；另外透過Keil_V5編寫MCU程式進行複雜數據計算以節省FPGA資源；最後使用MATLAB將FDRR透過JTAG擷取之IQ訊號與特定ZC序列進行相關性驗證，證明在實際場域測試時，針對數台FDRRs同頻同時互相傳輸BT與資料之各種干擾問題是否被解決以及驗證通道預約的可行性。 ;One of the applications of 5th-Generation Mobile Communication Technology (5G) is ultra-reliable and low latency communications (URLLC), which focuses on features such as low latency and high reliability. If one wants to realize URLLC service in the unlicensed spectrum, he/she may face many challenges, such as the interference from heterogeneous Wi-Fi networks. Based on our previous researches, which proposed the channel reservation mechanism (CRM) over unlicensed spectrum, this thesis attempts to utilize a full-duplex radio repeater (FDRR) platform to achieve channel reservation by continuously emitting the Busy Tone (BT) in unlicensed channel in order to occupy that channel, meanwhile these FDRRs are able to transmit control/data signals to each other without the disturb from Wi-Fi networks. The experiment is used to validate the feasibility of developing the proposed CRM for realizing the URLLC services in unlicensed spectrum. This thesis uses a number of FDRRs to play the roles of gNodeB (gNB) and user equipment (UE) in the 5G system, aiming to achieve channel reservation in unlicensed spectrum. All FDRRs emit ZC sequences of the same length but with different root indices as BTs, one index for one FDRR, and they use matched filters to effectively distinguish the source FDRRs by matching known ZC sequences. As a result, the gNB and UEs can transmit their BTs and receive the other BTs from other devices simultaneously. At the same time, the channel accessed by Wi-Fi devices will be temporarily occupied by the proposed CRM. Through Iperf (PCC/PCS) testing, the throughput of the Wi-Fi channel is used as an evidence to show that whether the channel is used by Wi-Fi devices or not, thus validating the capability of channel reservation. During the design phase, we utilize the Quartus tools to program in Verilog and then program the FPGA within the FDRR. Also, we employ the Keil_V5 to write firmware code for the MCU to process sophisticated calculation, aiming to conserve FPGA resources. Finally, we utilize MATLAB to confirm the correlation between the IQ signals extracted from the FDRR via JTAG and then identify the received ZC sequences. Experiments have been established to validate that multiple FDRRs are able to communicate with each other without the disturb from homogeneous and heterogeneous interferences during field tests, which in turn also confirms the ability of channel reservation.
Appears in Collections:	[Executive Master of Communication Engineering] Electronic Thesis & Dissertation

Files in This Item:

File	Description	Size	Format
index.html		0Kb	HTML	36	View/Open

社群 sharing

Loading...