在這篇論文中，我們考慮分段編碼ALOHA(CSA)系統。在這些系統中，在其他地方成功接收到的封包是否可以成功地減少其對另一個封包的接收的干擾，取決於該封包的發送端和發生取消事件的接收器間距。在本研究中，我們假設如果封包的訊雜比大於一個閥值，則可以被成功接收。假設一個封包在其他地方被成功接收，則其可以藉由適當的通道增益測量有效地減少在其他位置同個封包對其它封包所造成的干擾。我們對通道測量誤差提出一個簡易的距離相依模型。我們對使用者與接收者之間的空間關係提出兩種形容位置的模型。這兩種模型主要是描述距離分布，該距離是使用者與接收者之間的距離。在給定不同的封包數量及干擾消除的環境中，我們也描述了信號與干擾加噪音比(SINR)大於一定閥值的條件機率。
我們透過各種的擬真模擬實驗證明我們的理論性推導結果可以很好的描述擬真模擬的結果。

In this paper, we consider coded slotted ALOHA (CSA) systems. In these systems, whether a packet successfully received elsewhere can be used successfully to reduce its interference to the reception of another packet depends on the distance between the transmitter of this packet and the receiver where the cancellation is occurring. In this study, we assume that a packet is successfully received if the signal to interference and noise ratio (SINR) of the packet is greater than a threshold. If a packet is successfully received elsewhere, its interference to the correct reception of another packet can be reduced by properly estimating the channel gain from the transmitter of the packet to the current receiver. We propose a simple model for the channel estimation error, which is distance dependent. We propose two models for the locations of users and receivers. For these two models, we derive distribution for the distance between users and receivers. We also derive the conditional probability that the SINR is greater than the threshold, given the number of packets used for interference cancellation. We verify through extensive simulations that our theoretical results can approximately match with the simulation results.

中文摘要. . . . . . . . . . i
Abstract . . . . . . . . . . ii
Acknowledgements . . . . . . . . . . iii
List of Figures . . . . . . . . . . vi
List of Tables . . . . . . . . . . vii
1 Introduction . . . . . . . . . . 1
2 Interference Cancellation . . . . . . . . . . 3
2.1 Ideal Successive Interference Cancellation . . . . . . . . 3
2.2 Non-ideal Successive Interference Cancellation . . . . . 5
2.3 A Model for Channel Estimation Error . . . . . . . . . . 7
3 System Model and Analysis . . . . . . . . . . 10
3.1 System Model . . . . . . . . . . . . . . . . . . . . . . . 10
3.2 Iterative Analysis . . . . . . . . . . . . . . . . . . . . . 11
3.3 Analysis of f_{k,n-k} . . . . . . . . . . . . . . . . . . . . . 18
3.3.1 Case: Model I . . . . . . . . . . . . . . . . . . . 20
3.3.2 Case: Model II . . . . . . . . . . . . . . . . . . 23
4 Numerical Results . . . . . . . . . . 27
4.1 Throughput on Non-ideal SIC . . . . . . . . . . . . . . 27
4.1.1 The Impact of the Load in Model I . . . . . . . . 28
4.1.2 The Impact of the Load in Model II . . . . . . . 29
4.1.3 The Number of Iterations . . . . . . . . . . . . . 30
4.2 A Use Case for URLLC and eMBB Users . . . . . . . . 31
5 Conclusions . . . . . . . . . . 36
Bibliography . . . . . . . . . . 39

[1] L. G. Roberts, “Aloha packet system with and without slots and capture,” ACM SIGCOMM Computer Communication Review, vol. 5, no. 2, pp. 28–42, 1975.
[2] W. Liu, X. Sun, W. Zhan, and X. Wang, “Maximum sum rate of
slotted aloha for mmtc with short packet,” in 2020 IEEE/CIC International Conference on Communications in China (ICCC), 2020, pp. 1068–1073.
[3] G. Ma, B. Ai, F. Wang, and Z. Zhong, “Joint design of coded tandem
spreading multiple access and coded slotted aloha for massive machine-type communications,” IEEE Transactions on Industrial Informatics, vol. 14, no. 9, pp. 4064–4071, 2018.
[4] G. Choudhury and S. Rappaport, “Diversity aloha-a random access scheme for satellite communications,” IEEE Transactions on Communications, vol. 31, no. 3, pp. 450–457, 1983.
[5] M. Zhang, L. de Alfaro, and J. Garcia-Luna-Aceves, “An adaptive tree algorithm to approach collision-free transmission in slotted
aloha,” 2020.
[6] E. Casini, R. De Gaudenzi, and O. D. R. Herrero, “Contention resolution diversity slotted aloha (crdsa): An enhanced random access scheme for satellite access packet networks,” IEEE Transactions on Wireless Communications, vol. 6, no. 4, pp. 1408–1419, 2007.
[7] G. Liva, “A slotted aloha scheme based on bipartite graph optimization,” in 2010 International ITG Conference on Source and Channel Coding (SCC). IEEE, 2010, pp. 1–6.
[8] G. Liva, “Graph-based analysis and optimization of contention resolution diversity slotted aloha,” IEEE Transactions on Communications, vol. 59, no. 2, pp. 477–487, 2011.
[9] Cˇ . Stefanovic´, M. Momoda, and P. Popovski, “Exploiting capture effect in frameless aloha for massive wireless random access,” in 2014 IEEE Wireless Communications and Networking Conference
(WCNC). IEEE, 2014, pp. 1762–1767.
[10] D. Jakoveti´c, D. Bajovi´c, D. Vukobratovi´c, and V. Crnojevi´c, “Cooperative slotted aloha for multi-base station systems,” IEEE Transactions on Communications, vol. 63, no. 4, pp. 1443–1456, 2015.
[11] C.-H. Yu, L. Huang, C.-S. Chang, and D.-S. Lee, “Poisson receivers: a probabilistic framework for analyzing coded random access,” arXiv preprint arXiv:2008.07561, 2020.
[12] Y. Yu and G. B. Giannakis, “High-throughput random access using successive interference cancellation in a tree algorithm,” IEEE Transactions on Information Theory, vol. 53, no. 12, pp. 4628–4639, 2007.
[13] P. Palau Puigdevall, “Massive tdma for satellite communications,” B.S. thesis, Universitat Politècnica de Catalunya, 2017.
[14] N. Garcia, H. Wymeersch, E. G. Ström, and D. Slock, “Locationaided mm-wave channel estimation for vehicular communication,” in 2016 IEEE 17th International Workshop on Signal Processing Advances in Wireless Communications (SPAWC). IEEE, 2016, pp. 1–5.
[15] J. G. Andrews, R. K. Ganti, M. Haenggi, N. Jindal, and S. Weber, “A primer on spatial modeling and analysis in wireless networks,” IEEE Communications Magazine, vol. 48, no. 11, pp. 156–163, 2010.
[16] M. Hata, “Empirical formula for propagation loss in land mobile radio services,” IEEE transactions on Vehicular Technology, vol. 29, no. 3, pp. 317–325, 1980.
[17] L. Toni and P. Frossard, “Prioritized random mac optimization via graph-based analysis,” IEEE Transactions on Communications, vol. 63, no. 12, pp. 5002–5013, 2015.
[18] V.-D. Nguyen, M. Patzold, F. Maehara, H. Haas, and M.-V. Pham, “Channel estimation and interference cancellation for mimo-ofdm systems,” IEICE transactions on communications, vol. 90, no. 2,
pp. 277–290, 2007.
[19] A. Masmoudi and T. Le-Ngoc, “Channel estimation and self interference cancelation in full-duplex communication systems,” IEEE Transactions on Vehicular Technology, vol. 66, no. 1, pp.
321–334, 2016.
[20] M. Newman, Networks. Oxford university press, 2018.