Open AccessEnergy and spectral efficiency of secure massive MIMO downlink systems
Author(s) -
Alnahari Azzam,
Sakran Hefdhallah,
Su Weifeng,
Tarbosh Sami
Publication year - 2019
Publication title -
iet communications
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.355
H-Index - 62
eISSN - 1751-8636
pISSN - 1751-8628
DOI - 10.1049/iet-com.2018.5567
Subject(s) - spectral efficiency , telecommunications link , precoding , mimo , computer science , efficient energy use , transmitter power output , ergodic theory , channel (broadcasting) , mathematics , computer network , transmitter , mathematical analysis , electrical engineering , engineering
Spectral efficiency, energy efficiency, and security are cornerstones for the upcoming 5G systems. In this study, the issue of how the energy and spectral efficiency of multiuser massive multiple‐input multiple‐output (Ma‐MIMO) systems are affected in the presence of a secrecy constraint is addressed. The performance of the two most prominent linear precoding techniques, the matched filter (MF) and zero‐forcing (ZF) precoders, for secure downlink multiuser Ma‐MIMO in the presence of multi‐antenna passive eavesdropper is investigated. The authors consider three performance metrics, namely, the achievable ergodic secrecy rate, the secrecy spectral efficiency (SSE), and the secrecy energy efficiency (SEE), assuming perfect and imperfect channel state information. The tradeoff between SSE and SEE is also studied. Moreover, the authors derive tight lower bounds on the achievable ergodic secrecy rate for MF and ZF precoding techniques. The derived lower bounds provide insights on the tradeoff between the SSE and SEE. It is shown that ZF precoder outperforms MF precoder at high transmit power, whereas at very low transmit power, MF outperforms ZF. Moreover, it is shown that using large number of transmit antennas can improve the SSE and the SEE with orders of magnitude compared to a single‐input single‐output system.