We consider the problem of transmit beamforming to multiple cochannel multicast groups. The conventional approach is to beamform a designated data stream to each group, while treating potential inter-group interference as noise at the receivers. In overloaded systems where the number of transmit antennas is insufficient to perform interference nulling, we show that inter-group interference dominates at high SNRs, leading to a saturating max-min fair performance. We propose a rather unconventional approach to cope with this issue based on the concept of Rate-Splitting (RS). In particular, part of the interference is broadcasted to all groups such that it is decoded and canceled before the designated beams are decoded. We show that the RS strategy achieves significant performance gains over the conventional multigroup multicast beamforming strategy.
|Title of host publication||SPAWC 2016 - 17th IEEE International Workshop on Signal Processing Advances in Wireless Communications|
|Publisher||Institute of Electrical and Electronics Engineers Inc.|
|Publication status||Published - 2016 Aug 9|
|Event||17th IEEE International Workshop on Signal Processing Advances in Wireless Communications, SPAWC 2016 - Edinburgh, United Kingdom|
Duration: 2016 Jul 3 → 2016 Jul 6
|Name||IEEE Workshop on Signal Processing Advances in Wireless Communications, SPAWC|
|Other||17th IEEE International Workshop on Signal Processing Advances in Wireless Communications, SPAWC 2016|
|Period||16/7/3 → 16/7/6|
Bibliographical noteFunding Information:
This work has been partially supported by the UK EPSRC under grant number EP/N015312/1.
© 2016 IEEE.
- WMMSE approach
- degrees of freedom
- downlink beamforming
ASJC Scopus subject areas
- Electrical and Electronic Engineering
- Computer Science Applications
- Information Systems