Precoder Design For Multi-Group Multicasting With a Common Message

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Yalcin A. Z. , YÜKSEL TURGUT A. M.

IEEE TRANSACTIONS ON COMMUNICATIONS, vol.67, no.10, pp.7302-7315, 2019 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 67 Issue: 10
  • Publication Date: 2019
  • Doi Number: 10.1109/tcomm.2019.2931580
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.7302-7315
  • Keywords: Common and private data transmission, multicast transmission, multiple input multiple output, physical layer precoding, superposition coding, SUM-RATE MAXIMIZATION, MIMO BROADCAST, CHANNEL
  • Middle East Technical University Affiliated: No


This paper considers precoding for multi-group multicasting with a common message. The multiple antenna base station communicates with K clusters, each with L users. There is a common message destined to all users and a private multicast message for each cluster. We study the weighted sum rate (WSR) maximization problem for two different schemes: 1) the base station transmits the superposition of common and multicast messages and 2) the base station concatenates the multicast message vector with the common message. We also formulate a second problem, weighted minimum mean square error (WMMSE) minimization, and prove that WSR maximization and WMMSE minimization are equivalent at the optimal solution. Inspired by the WMMSE problem, we suggest a suboptimal algorithm, based on alternating optimization. We apply this algorithm to the two transmission schemes and understand that there is a fundamental difference between the two. We compare the results with maximal ratio transmission (MRT) and zero-forcing (ZF) precoding and investigate the effects of the number of base station antennas, the number of groups, and the number of users in a group. Finally, we study imperfect successive interference cancellation (SIC) at the receivers and show that the first transmission scheme is more robust.