Analysis of irregular repetition spatially-coupled slotted ALOHA


Contention-based access is a promising technology for massive and sporadic transmissions. In this paper, we propose a novel contention-based multiple access scheme, named irregular repetition spatially-coupled slotted ALOHA (IRSC-SA), motivated by the spatial coupling and irregular repetition techniques. There are different classes of users and slots in IRSC-SA, which result in unequal protection for different users. Considering that, we derive a novel density evolution (DE) method, which deals with unequal packet protection and introduces Bayesian reasoning to analyze the throughput threshold of the proposed IRSC-SA. Theoretical analysis and simulation results show that the proposed scheme achieves better asymptotic threshold and system packet throughput performance than the conventional spatially-coupled slotted ALOHA.

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This work was partially supported by Beijing Natural Science Foundation (Grant No. L182038), Chinese Ministry of Education-China Mobile Communication Corporation Research Fund (Grant No. MCM20170101), China National S&T Major Project (Grant No. 2017ZX03001017), National Natural Science Foundation of China (Grant No. 61871032), Beijing Major Science and Technology Projects (Grant No. D171100006317001), Ericsson company, and 111 Project of China (Grant No. B14010).

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Correspondence to Zesong Fei.

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Yu, H., Fei, Z., Cao, C. et al. Analysis of irregular repetition spatially-coupled slotted ALOHA. Sci. China Inf. Sci. 62, 80302 (2019).

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  • spatial coupling
  • coded slotted ALOHA
  • contention-based access
  • density evolution
  • irregular repetition