Multi-Source Spinal Coding for Coded Caching Multicast Transmissions in Wireless Networks

• 来源期刊: 中国通信（英文版）
• 年，卷（期）: 2021,（3）
• 所属期刊栏目: COMMUNICATIONS THEORIES & SYSTEMS
• 页码范围: 91-104
• 页数: 14页
• 语种: 英文

摘要

Recently, coded caching has been treated as a promising technique to alleviate the traffic burden in wireless networks. To support high efficient coded caching multicast transmissions, the time-varying het-erogeneous channel conditions need to be consid-ered. In this paper, a practical and novel multi-source spinal coding (MSSC) scheme is developed for coded caching multicast transmissions under heterogeneous channel conditions. By exploring joint design of network coding and spinal coding (SC), MSSC can achieve unequal link rates in multicast transmissions for different users. Moreover, by leveraging the rate-less feature of SC in our design, MSSC can well adapt the link rates of all users in multicast transmissions without any feedback of time-varying channel con-ditions. A maximum likelihood (ML) based decod-ing process for MSSC is also developed, which can achieve a linear complexity with respect to the user number in the multicast transmission. Simulation re-sults validate the effectiveness of the MSSC scheme. Compared to the existing scheme, the sum rate of MSSC in multicast transmissions is improved by about 20％. When applying MSSC in coded caching sys-tems, the total transmission time can be reduced by up to 48％for time-varying channels.