國際電信聯盟(International Telecommunication Union, ITU)於 2015 年 6 月提出
IMT-2020 計畫，計畫中明確定義了 5G 的三大方向為：增強型行動寬頻通訊(Enhanced
Mobile Broadband, eMBB)、大規模機器型通訊(Massive Machine Type Communications,
mMTC)和超可靠度和低延遲通訊(Ultra-reliable and Low Latency Communications,
URLLC)。本論文是針對 URLLC 方向中，在軟體實體層(Physical Layer, PHY)中對時
間敏感 PDCCH (Physical Downlink Control, PDCCH)來做設計。
依據 5G NR (5G New Radio)系統規格，我們將 PDCCH 上 Frequency Domain 佔
據的 Bandwidth Part 以及 Time Domain 上佔據的 OFDM Symbol 數量的訊息封裝在
CORESET 中；再將 PDCCH 開始位置的 OFDM Symbol 封裝在 Search Space 內；然
後，使用 gNB 把 PDCCH 的資訊擺放在 CORESET 裡面；而 UE 需要找到正確的
CORESET，這樣 UE 才能解出 PDCCH 的 DCI。另外，我們需要參照我們的 3GPP 規
格書來實現我們上述的 Search Space 以及 CORESET 的功能。接著我們需要針對 5G
NR PDCCH架構以及URLLC的低延遲加以設計優化。針對Search Space與CORESET
改寫程式碼並新增功能，透過多執行緒的平行程式來解決低延遲的問題。本研究實現
了 PDCCH 架構於 5G NR，並且其滿足了 URLLC 的低延遲需求。

International Telecommunication Union (ITU) proposed the IMT-2020 project in June 2015. The plan clearly defines three directions of 5G: Enhanced Mobile Broadband (eMBB), large-scale Massive Machine Type Communications (mMTC), and Ultra-reliable and Low Latency Communications (URLLC). This thesis is mainly to design the Soft-PHY (softwaredefined Physical Layer) time-sensitive PDCCH (Physical Downlink Control, PDCCH) for the URLLC. According to the 5G NR (5G New Radio) system specification, we encapsulate the information of PDCCH, concerning i) Bandwidth Part occupying in the frequency domain and ii) the amount of OFDM Symbols occupying in the time domain, into the CORESET. Then, we encapsulate the OFDM Symbol at the beginning of the PDCCH in the Search Space. The gNB is used to put the information of the PDCCH in the CORESET. The UE needs to find the correct CORESET so that the UE can solve the DCI of the PDCCH. Moreover, we need to refer to our 3GPP specification to implement our above Search Space and CORESET functions. Then, we have to optimize the 5G NR PDCCH architecture to meet the requirement of low latency for URLLC. We reprogram and add new function for Search Space and CORESET to solve low-latency problems through multiple-threading parallel programming. This study physically implements the PDCCH architecture for 5G NR and it satisfies the requirement of low latency for URLLC.

[1] 3GPP, “5G NR; Physical channels and modulation,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.211, 12 2018, version 15.4.0.
[2] 3GPP, “5G NR; Base Station (BS) radio transmission and reception,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.104, 12 2018, version 15.4.0
[3] 3GPP, “5G NR; Physical layer procedures for control,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.213, 12 2018, version 15.4.0.
[4] 3GPP, “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical Channels and Modulation,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 36.211, 02 2013, version 10.7.0
[5] 3GPP, “Evolved Universal Terrestrial Radio Access (E-UTRA); Physical layer procedures,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 36.213, 09 2012, version 10.7.0
[6] 3GPP, “Study on New Radio Access Technology; Physical Layer Aspects,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.802, 09 2017, version 14.2.0
[7] 3GPP, “5G NR; Physical channels and modulation,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.214, 12 2018, version 15.4.0.
[8] 3GPP, “5G NR; Radio Resource Control (RRC); Protocol specification,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.331, 12 2018, version 15.4.0.
[9] 3GPP, “5G NR; Multiplexing and channel coding,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.212, 12 2018, version 15.4.0.
[10] 3GPP, “5G NR; Physical layer measurements,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.215, 12 2018, version 15.4.0.
[11] 3GPP, “5G NR; Requirements for support of radio resource management,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.133, 12 2018, version 15.4.0.
[12] 3GPP, “5G NR; Medium Access Control (MAC) protocol specification,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.321, 12 2018, version 15.4.0.
[13] 3GPP, “5G NR; Radio Link Control (RLC) protocol specification,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.322, 12 2018, version 15.4.0.
[14] 3GPP, “5G NR; Physical layer; General description,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.201, 12 2017, version 15.0.0.
[15] 3GPP, “Study on New Radio Access Technology; Radio access architecture and interfaces,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.801, 03 2017, version 14.0.0.
[16] 3GPP, “Study on New Radio Access Technology; Physical Layer Aspects,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.802, 09 2017, version 14.2.0.
[17] 3GPP, “Study on New Radio Access Technology; Radio Interface Protocol Aspects,” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.804, 03 2017, version 14.0.0.
[18] 3GPP, “Study on physical layer enhancements for NR ultra-reliable and low latency case (URLLC),” 3rd Generation Partnership Project (3GPP), Technical Specification (TS) 38.824, 02 2019, version 1.0.1.
[19] T. Taleb, K. Samdanis, B. Mada, H. Flinck, S. Dutta, and D. Sabella, “On multi-access edge computing: A survey of the emerging 5G network edge cloud architecture and orchestration,” IEEE Communications Surveys & Tutorials, vol. 19, no. 3, pp. 1657-1681, May. 18, 2017.
[20] K. Katsalis, N. Nikaein, E. Schiller, A. Ksentini, and T. Braun, “Network slices toward 5G communications: Slicing the LTE network,” IEEE Communications Magazine, vol. 55, no. 8, pp. 146-154, Aug. 9, 2017.
[21] D. Boviz, C. S. Chen, and S. Yang, “Effective design of Multi-User reception and fronthaul rate allocation in 5G cloud RAN,” IEEE Journal on Selected Areas in Communications, vol. 35, no. 8, pp. 1825-1836, June. 01, 2017.
[22] C. Ranaweera, E. Wong, A. Nirmalathas, C. Jayasundara, and C. Lim, “5G C-RAN architecture: A comparison of multiple optical fronthaul networks,” International Conference on Optical Network Design and Modeling (ONDM), Budapest, Hungary, pp. 1-6. June. 26, 2017.
[23] G. Mountaser, M. L. Rosas, T. Mahmoodi, and M. Dohler, “On the feasibility of MAC and PHY split in cloud RAN,” IEEE Wireless Communications and Networking Conference (WCNC), San Francisco, CA, USA, pp. 1-6, May. 11, 2017.
[24] D. Bernstein, “Containers and cloud: From LXC to docker to Kubernetes,” IEEE Cloud Computing, vol. 1, no. 3, pp. 81-84, Sept. 2014.
[25] C. G. Kominos, N. Seyvet, and K. Vandikas, “Bare-metal, virtual machines and containers in OpenStack,” 20th Conference on Innovations in Clouds, Internet and Networks (ICIN), Paris, France, pp. 36-43. April. 17, 2017.
[26] A. Calinciuc, C. C. Spoiala, C. O. Turcu, and C. Filote, “OpenStack and Docker: Building a high-performance IaaS platform for interactive social media applications,” International Conference on Development and Application Systems (DAS), Suceava, Romania, pp. 287-290, June. 16, 2016.
[27] O. Neji, N. Chendeb, O. Chabbouh, N. Agoulmine, and S. Ben Rejeb, “Experience deploying a 5G C-RAN virtualized experimental setup using OpenAirInterface,” IEEE 17th International Conference on Ubiquitous Wireless Broadband (ICUWB), Salamanca, Spain, pp. 1-5, May. 09, 2017.
[28] P. Lin and S. Huang, “Performance profiling of cloud radio access networks using OpenAirInterface,” Asia-Pacific Signal and Information Processing Association Annual Summit and Conference (APSIPA ASC), Honolulu, HI, USA, pp. 454-458, March. 07, 2019.
[29] F. Kaltenberger, R. Knopp, M. Danneberg, and A. Festag, “Experimental analysis and simulative validation of dynamic spectrum access for coexistence of 4G and future 5G systems,” European Conference on Networks and Communications (EuCNC), Paris, France, pp. 497-501, Aug. 13, 2015.
[30] W. T. Han and R. Knopp, “OpenAirInterface: A pipeline structure for 5G,” IEEE 23rd International Conference on Digital Signal Processing (DSP), Shanghai, China, pp. 1-4, Feb. 04, 2019.
[31] D. Muirhead, M. A. Imran, and K. Arshad, “Insights and approaches for Low-Complexity 5G small-cell base-station design for indoor dense networks,” IEEE Access, vol. 3, pp. 1562-1572, Aug. 27, 2015.
[32] P. K. Mishra, S. Pandey, and S. K. Biswash, “Efficient resource management by exploiting D2D communication for 5G networks,” IEEE Access, vol. 4, pp. 9910-9922, Sep. 07, 2016.
[33] S. Schwarz and M. Rupp, “Exploring coordinated multipoint beamforming strategies for 5G cellular,” IEEE Access, vol. 2, pp. 930-946, Aug. 29, 2014.
[34] A. Omri, M. Shaqfeh, A. Ali, and H. Alnuweiri, “Synchronization procedure in 5G NR systems,” IEEE Access, vol. 7, pp. 41286-41295, March. 28, 2019.
[35] G. Hattab, E. Visotsky, M. C. Cudak, and A. Ghosh, “Uplink interference mitigation techniques for coexistence of 5G millimeter wave users with incumbents at 70 and 80 GHz,” IEEE Transactions on Wireless Communications, vol. 18, no. 1, pp. 324-339, Jan. 19, 2019.
[36] J. Liu, H. Wang, C. Shen, and J. Lee, “Low-complexity LDPC decoder for 5G URLLC,” IEEE Asia Pacific Conference on Postgraduate Research in Microelectronics and Electronics (PrimeAsia), Chengdu, China, pp. 43-46, Jan. 03, 2018.
[37] A. Tusha, S. Doğan, and H. Arslan, “Single carrier transmission for URLLC with adaptive radio resource utilization,” 15th International Wireless Communications & Mobile Computing Conference (IWCMC), Tangier, Morocco, pp. 26-30, May. 05, 2019.
[38] B. Chang, G. Zhao, M. A. Imran, Z. Chen, and L. Li, “Dynamic wireless QoS analysis for real-time control in URLLC,” IEEE Globecom Workshops (GC Wkshps), Abu Dhabi, United Arab Emirates, pp. 1-5, Feb. 21, 2019.
[39] Z. Li, M. A. Uusitalo, H. Shariatmadari, and B. Singh, “5G URLLC: Design challenges and system concepts,” 15th International Symposium on Wireless Communication Systems (ISWCS), Lisbon, Portugal, pp. 1-6, May. 11, 2018.
[40] J. Rao and S. Vrzic, “Packet duplication for URLLC in 5G dual connectivity architecture,” IEEE Wireless Communications and Networking Conference (WCNC), Barcelona, Spain, pp. 1-6, Feb. 05, 2018.
[41] T. Fehrenbach, R. Datta, B. Göktepe, T. Wirth, and C. Hellge, “URLLC services in 5G low latency enhancements for LTE,” IEEE 88th Vehicular Technology Conference (VTC-Fall), Chicago, IL, USA, pp. 1-6, May. 11, 2018.
[42] D. Maaz, A. Galindo-Serrano, and S. E. Elayoubi, “URLLC user plane latency performance in new radio,” 25th International Conference on Telecommunications (ICT), St. Malo, France, pp. 225-229, Sept. 17, 2018.
[43] F. Nabil and Y. A. Fahmy, “Scattered search space scheme for PDCCH and ePDCCH in LTE-advanced,” International Congress on Ultra Modern Telecommunications and Control Systems and Workshops (ICUMT), Brno, Czech, pp. 172-177, Jan. 14, 2016.
[44] Xiaoli Chen, Wei Yang, and Changlong Xu, “Novel resource allocation schemes in LTE PDCCH,” IEEE 14th International Conference on Communication Technology, Chengdu, China, pp. 128-132, May. 02, 2012.
[45] F. Hamidi-Sepehr, Y. Kwak, and D. Chatterjee, “5G NR PDCCH: Design and performance,” IEEE 5G World Forum (5GWF), Silicon Valley, CA, USA, pp. 250-255, Nov. 01, 2018.
[46] H. Miao and M. Faerber, “Configurable distributed physical downlink control channel for 5G new radio: Resource bundling and diversity trade-off,” IEEE Wireless Communications and Networking Conference Workshops (WCNCW), Barcelona, Spain, pp. 368-372, May. 31, 2018.
[47] Q. Xiong, B. Yu, C. Qian, X. Li, and C. Sun, “Random access preamble generation and procedure design for 5G-NR system,” IEEE Globecom Workshops (GC Wkshps), Abu Dhabi, United Arab Emirates, pp. 1-5, Feb. 21, 2018.
[48] F. W. Vook, A. Ghosh, E. Diarte, and M. Murphy, “5G new radio: Overview and performance,” 52nd Asilomar Conference on Signals, Systems, and Computers, Pacific Grove, CA, USA, pp. 1247-1251, Feb. 21, 2018.
[49] M. Khoshnevisan, V. Joseph, P. Gupta, F. Meshkati, R. Prakash, and P. Tinnakornsrisuphap, “5G industrial networks with CoMP for URLLC and time sensitive network architecture,” IEEE Journal on Selected Areas in Communications, vol. 37, no. 4, pp. 947-959, Feb. 18, 2019.
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[51] "LTE University," http://lteuniversity.com/