Machine Learning aided Channel Estimation for Cell-Free Networks using a
novel pilot assignment algorithm
Abstract
Cell-free massive multiple-input multiple-output (CFMM) network is
projected as the latest technology for the fifth-generation and beyond
wireless networks. The recent research trend is to extensively study and
analyse CFMM network for its advantages and bottlenecks. The CFMM
network is strongly affected by pilot contamination (PC) which is one of
the bottlenecks due to which quality of service (QoS) and accuracy of
channel estimation gets impacted. Therefore, we address this problem by
presenting a novel pilot assignment algorithm to mitigate PC and deep
learning aided channel estimation for reducing channel estimation error
for the CFMM systems to maximize spectral efficiency. We derive
achievable UL and DL spectral efficiency (SE) expressions for the
proposed system, and compared with Minimum Mean Square Error(MMSE) and
Maximum Ratio (MR) combining techniques. The performance of cellular
massive MIMO is derived for comparison. For the same cellular set up,the
proposed CFMM system achieves higher SE than the cellular massive MIMO.
Numerical results prove the efficacy of the proposed CFMM system to some
of the existing schemes in this domain.