TY - JOUR
T1 - Rate-Splitting to Mitigate Residual Transceiver Hardware Impairments in Massive MIMO Systems
AU - Papazafeiropoulos, Anastasios
AU - Clerckx, Bruno
AU - Ratnarajah, Tharmalingam
N1 - Funding Information:
Manuscript received October 16, 2016; revised February 17, 2017 and March 28, 2017; accepted March 31, 2017. Date of publication April 5, 2017; date of current version September 15, 2017. This work was supported by the U.K. Engineering and Physical Sciences Research Council (EPSRC) under Grants EP/N014073/1 and EP/N015312/1. The review of this paper was coordinated by Prof. D. B. da Costa. (Corresponding author: Anastasios Papazafeiropoulos.) A. Papazafeiropoulos and T. Ratnarajah are with the Institute for Digital Communications (IDCOM), University of Edinburgh, Edinburgh EH9 3JL, U.K. (e-mail: a.papazafeiropoulos; t.ratnarajah@ed.ac.uk).
Publisher Copyright:
© 2017 IEEE.
PY - 2017/9
Y1 - 2017/9
N2 - Rate-splitting (RS) has recently been shown to provide significant performance benefits in various multiuser transmission scenarios. In parallel, the huge degrees-of-freedom provided by the appealing massive multiple-input multiple-output (MIMO) necessitate the employment of inexpensive hardware, being more prone to hardware imperfections, in order to be a cost-efficient technology. Hence, in this paper, we focus on a realistic massive multiple-input single-output broadcast channel hampered by the inevitable hardware impairments. We consider a general experimentally validated model of hardware impairments, accounting for the presence of multiplicative distortion due to phase noise, additive distortion noise and thermal noise amplification. Under both scenarios with perfect and imperfect channel state information at the transmitter (CSIT), we analyze the potential robustness of RS to each separate hardware imperfection. We analytically assess the sum-rate degradation due to hardware imperfections. Interestingly, in the case of imperfect CSIT, we demonstrate that RS is a robust strategy for multiuser MIMO in the presence of phase and amplified thermal noise, since its sum-rate does not saturate at high signal-to-noise ratio (SNR), contrary to conventional techniques. On the other hand, the additive impairments always lead to a sum-rate saturation at high SNR, even after the application of RS. However, RS still enhances the performance. Furthermore, as the number of users increases, the gains provided by RS decrease not only in ideal conditions, but in practical conditions with residual transceiver hardware impairments as well. Notably, although a deterministic equivalent analysis is employed, the analytical and simulation results coincide even for finite system dimensions. As a consequence, the applicability of these results also holds for current 'small scale' multiantenna systems.
AB - Rate-splitting (RS) has recently been shown to provide significant performance benefits in various multiuser transmission scenarios. In parallel, the huge degrees-of-freedom provided by the appealing massive multiple-input multiple-output (MIMO) necessitate the employment of inexpensive hardware, being more prone to hardware imperfections, in order to be a cost-efficient technology. Hence, in this paper, we focus on a realistic massive multiple-input single-output broadcast channel hampered by the inevitable hardware impairments. We consider a general experimentally validated model of hardware impairments, accounting for the presence of multiplicative distortion due to phase noise, additive distortion noise and thermal noise amplification. Under both scenarios with perfect and imperfect channel state information at the transmitter (CSIT), we analyze the potential robustness of RS to each separate hardware imperfection. We analytically assess the sum-rate degradation due to hardware imperfections. Interestingly, in the case of imperfect CSIT, we demonstrate that RS is a robust strategy for multiuser MIMO in the presence of phase and amplified thermal noise, since its sum-rate does not saturate at high signal-to-noise ratio (SNR), contrary to conventional techniques. On the other hand, the additive impairments always lead to a sum-rate saturation at high SNR, even after the application of RS. However, RS still enhances the performance. Furthermore, as the number of users increases, the gains provided by RS decrease not only in ideal conditions, but in practical conditions with residual transceiver hardware impairments as well. Notably, although a deterministic equivalent analysis is employed, the analytical and simulation results coincide even for finite system dimensions. As a consequence, the applicability of these results also holds for current 'small scale' multiantenna systems.
KW - Deterministic equivalent analysis
KW - massive MIMO
KW - rate-splitting
KW - regularized zero-forcing precoding
KW - residual hardware impairments
UR - http://www.scopus.com/inward/record.url?scp=85029922735&partnerID=8YFLogxK
U2 - 10.1109/TVT.2017.2691014
DO - 10.1109/TVT.2017.2691014
M3 - Article
AN - SCOPUS:85029922735
VL - 66
SP - 8196
EP - 8211
JO - IEEE Transactions on Vehicular Technology
JF - IEEE Transactions on Vehicular Technology
SN - 0018-9545
IS - 9
M1 - 7892949
ER -