利用用戶設備（UE）之間Device-to-Device（D2D）的直接通訊，使蜂巢網路可以利用不同場景提供各種服務，更由於基站（BS）不參與傳輸，因此進而減少了傳輸距離和能源消耗。但是，由D2D 通訊引起的不可避免的干擾使傳輸質量的分析更加複雜。隨機幾何被認為是分析蜂巢網路中D2D 通訊性能的易處理工具，Poisson point process（PPP）在近期也已被廣泛使用。但是，攜帶UE的人員通常以群集的方式聚集，因此，本文將Poisson cluster process（PCP）引入分析中，使隨機幾何假設更加合理和實用。此外，在傳輸信道中假定了更複雜的一般衰落。在經典的基於距離的模式選擇下，我們得出D2D 和蜂巢鏈路覆蓋率的封閉形式結果。我們還進行了廣泛的仿真實驗，以驗證所提出分析模型的正確性。所提出的分析模型可以準確地捕獲D2D 通訊的行為，並且可以用作評估模式選擇方案性能的工具。

With direct device-to-device (D2D) communications between user equipments (UEs),
various kinds of services can be provided by cellular networks for different scenarios since base station (BS) does not involve in the data transmissions, thereby decreasing transmission distance and lowering the power consumption. However, the unavoidable interference caused by D2D communications makes the analysis of transmission quality much more complicated. Stochastic geometry is considered a tractable tool to analyze the performance of D2D communications in cellular networks, and Poisson point process (PPP) has been widely used recently. However, people who carry UEs typically gather in a clustered fashion, and this thesis, therefore, introduces Poisson cluster process (PCP) into the analysis so that the geometry assumption is more reasonable and practical. Moreover, more complicated general fading is assumed in the transmission channel. Under a classic distance-based mode selection, we derive closed-form results of coverage probability for both D2D and cellular links. We also conduct an extensive simulation experiment to verify the correctness of the proposed analytical model. The proposed analytical model captures the behavior of D2D communications precisely and can be applied as a tool to evaluate the performance of mode selection schemes.

[1] M. Afshang and H. S. Dhillon, “Poisson cluster process based analysis of HetNets with correlated user and base station locations,” IEEE Trans. Wireless Commun., vol. 17, no. 4, pp. 2417–2431, January 2018.

[2] C. Saha, M. Afshang, and H. S. Dhillon, “3GPP-inspired HetNet model using poisson cluster process: Sum-product functionals and downlink coverage,” IEEE Trans. Wireless Commun., vol. 66, no. 5, pp. 2219–2234, August 2017.

[3] ——, “Enriched k-tier HetNet model to enable the analysis of usercentric small cell deployments,” IEEE Trans. Wireless Commun., vol. 16, no. 3, pp. 1593–1608, January 2017.

[4] ——, “Poisson cluster process: Bridging the gap between PPP and 3GPP HetNet models,” in Proc. IEEE ITA 2017, August 2017, pp. 1–9.

[5] A. Asadi, Q. Wang, and V. Mancuso, “A survey on device-to-device communication in cellular networks,” IEEE Commun. Surveys Tuts., vol. 16, no. 4, pp. 1801–1819, Fourth quarter 2014.

[6] D. Feng, L. Lu, Y.-Y. Wu, G. Y. Li, S. Li, and G. Feng, “Device-to-device communications in cellular networks,” IEEE Commun. Mag., vol. 52, no. 4, pp. 49–55, April 2014.

[7] Y. J. Wang and S. M. Cheng, “Mode selection for device-to-device communications with channel fading in underlay cellular network.”

[8] S. Joshi and R. K. Mallik, “Coverage and interference in D2D networks with poisson cluster process,” IEEE Commun. Lett., vol. 22, no. 5, pp. 1098–1101, February 2018.

[9] E. Turgut and M. C. Gursoy, “Uplink performance analysis in D2D-enable mmwave cellular networks with clustered users,” IEEE Trans. Wireless Commun., January 2019.

[10] H. Ding, X. Wang, D. B. da Costa, and J. Ge, “Interference modeling in clustered device-to-device networks with uniform transmitter selection,” IEEE Trans. Wireless Commun., vol. 16, no. 12, pp. 7906–7918, September 2017.

[11] M. Afshang, H. S. Dhillon, and P. H. J. Chong, “Modeling and performance analysis of clustered device-to-device networks,” IEEE Trans. Wireless Commun., vol. 15, no. 7, pp. 4957–4972, August 2016.

[12] M. Afshang and H. S. Dhillon, “Spatial modeling of device-to-device networks: Poisson cluster process meets poisson hole process,” in Proc. IEEE ACSSC 2015, February 2015, pp. 317–321.

[13] W. Yi, Y. Liu, and A. Nallanathan, “Modeling and analysis of D2D millimeter-wave networks with poisson cluster processes,” IEEE Trans. Commun., vol. 65, no. 12, pp. 5574–5588, August 2017.

[14] J. Lyu, T.-X. Zheng, K.-W. Huang, Y. Feng, and H.-M. Wang, “Secure transmissions of D2D underlay cellular networks with poisson cluster process,” Proc. IEEE GLOBECOM 2019, December 2019.

[15] M. Afshang, C. Saha, and H. S. Dhillon, “Nearest-neighbor and contact distance distributions for thomas cluster process,” IEEE Wireless Commun. Lett., vol. 6, no. 1, pp. 130–133, December 2016.

[16] M. Haenggi, Stochastic geometry for wireless networks. Cambridge University Press, July 2012.

[17] M. Haenggi, J. G. Andrews, F. Baccelli, O. Dousse, and M. Franceschetti, “Stochastic geometry and random graphs for the analysis and design of wireless networks,” IEEE J. Sel. Areas Commun., vol. 27, no. 7, pp. 1029–1046, September 2009.

[18] C. Saha and H. S. Dhillon, “Downlink coverage probability of k-tier HetNets with general non-uniform user distributions,” in Proc. IEEE ICCS 2016, July 2016, pp. 1–6.

[19] H. S. Dhillon, R. K. Ganti, F. Baccelli, and J. G. Andrews, “Modeling and analysis of k-tier downlink heterogeneous cellular networks,” IEEE J. Sel. Areas Commun., vol. 30, no. 3, pp. 550–560, March 2012.

[20] J. G. Andrews, F. Baccelli, and R. K. Ganti, “A tractable approach to coverage and rate in cellular networks,” IEEE Trans. Commun., vol. 59, no. 11, pp. 3122–3134, November 2011.

[21] R. Amer, M. M. Butt, H. ElSawy, M. Bennis, J. Kibiłda, and N. Marchetti, “On minimizing energy consumption for D2D clustered caching networks,” Proc. IEEE GLOBECOM 2018, August 2018.

[22] Y. J. Chun, M. O. Hasna, and A. Ghrayeb, “Modeling heterogeneous cellular networks interference using poisson cluster processes,” IEEE J. Sel. Areas Commun., vol. 33, no. 10, pp. 2182–2195, May 2015.

[23] D. Della Penda, R. Wichman, T. Charalambous, G. Fodor, and M. Johansson, “A distributed mode selection scheme for full-duplex device-to-device communication,” IEEE Trans. Veh. Technol., July 2019.

[24] D. Zhai, R. Zhang, Y. Wang, H. Sun, L. Cai, and Z. Ding, “Joint user pairing, mode selection, and power control for D2D-capable cellular networks enhanced by nonorthogonal multiple access,” IEEE Internet Things J., vol. 6, no. 5, pp. 8919–8932, June 2019.

[25] J. Lin, Q. Shi, Q. Li, and D. Zhao, “Joint mode selection and transceiver design for device-to-device communications underlaying multi-user MIMO cellular networks,” IEEE Trans. Wireless Commun., vol. 18, no. 6, pp. 3312–3328, May 2019.

[26] S. W. H. Shah, M. M. U. Rahman, A. N. Mian, A. Imran, S. Mumtaz, and O. A. Dobre, “On the impact of mode selection on effective capacity of device-to-device communication,” IEEE Wireless Commun. Lett., February 2019.

[27] D. Della Penda, L. Fu, and M. Johansson, “Mode selection for energy efficient D2D communications in dynamic TDD systems,” in Proc. IEEE ICC 2015, September 2015, pp. 5404–5409.

[28] R. Wang, J. Zhang, S. Song, and K. B. Letaief, “QoS-aware joint mode selection and channel assignment for D2D communications,” in Proc. IEEE ICC 2013, July 2016, pp. 1–6.

[29] F. Belloni, “Fading models,” Postgraduate Course in Radio Communications,
pp. 1–4, September 2004.

[30] Y. J. Chun, S. L. Cotton, H. S. Dhillon, A. Ghrayeb, and M. O. Hasna, “A stochastic geometric analysis of device-to-device communications operating over generalized fading channels,” IEEE Trans. Wireless Commun., vol. 16, no. 7, pp. 4151–4165, March 2017.

[31] V. Suryaprakash, J. Moller, and G. Fettweis, “On the modeling and analysis of heterogeneous radio access networks using a poisson cluster process,” IEEE Trans. Wireless Commun., vol. 14, no. 2, pp. 1035–1047, October 2015.

[32] Z. Hussain, A. U. R. Khan, H. Mehdi, and S. M. A. Saleem, “Analysis of D2D communications over gamma Nakagami fading channels,” Engineering, Technology & Applied Science Research, vol. 8, no. 2, pp. 2693–2698, November 2018.

[33] Y. J. Chun, S. L. Cotton, H. S. Dhillon, F. J. Lopez-Martinez, J. F. Paris, and S. K. Yoo, “A comprehensive analysis of 5G heterogeneous cellular systems operating over  ?  shadowed fading channels,” IEEE Trans. Wireless Commun., vol. 16, no. 11, pp. 6995–7010, August 2017.

[34] B. Kaufman, J. Lilleberg, and B. Aazhang, “Spectrum sharing scheme between cellular users and ad-hoc device-to-device users,” IEEE Trans. Wireless Commun., vol. 12, no. 3, pp. 1038–1049, March 2013.

[35] S. Shirvani Moghaddam, “Outage analysis of energy harvested relayaided device-to-device communications in Nakagami channel,” November 2018.

[36] S. Joshi and R. K. Mallik, “Analysis of dedicated and shared device-to-
device communication in cellular networks over Nakagami-m fading channels,” IET Communications, vol. 11, no. 10, pp. 1600–1609, July 2017.

[37] A. Annamalai, C. Tellambura, and V. K. Bhargava, “Simple and accurate methods for outage analysis in cellular mobile radio systems-a unified approach,” IEEE Trans. Commun., vol. 49, no. 2, pp. 303–316, February 2001.