A Novel Robust Detector for Cell-Free Massive MIMO System

Massive MIMO increases spectral efficiency and energy efficiency in 5G by using beamforming and spatial multiplexing. It employs a centralized solution to densify a network, resulting in intercellular interference because of its cell-centric design. Massive MIMO systems enable user-centric transmission in cellular networks to overcome inter-cell interference limitations and provide macro-diversity. Massive MIMO distinguishes itself from coordinated, distributed wireless systems with its scalability and cell-free design. This article investigates the immense potential of our proposed detector, this promising technology, and practical deployment issues due to signal coprocessing's increased backhauling overhead. We propose a conjugate gradient (CG)-based detector that enables fast-er convergence and smaller approximated errors for cell-free massive MIMO systems. An analytical approach describes the asymptotic performance of a con-jugate gradient-based likelihood ascent search detector with massive antennas. A joint channel estimation and signal detection (JCD) method is also used for real-world scenarios with imperfect channel state information (CSI). As a result of simulations, our proposed detection scheme outperforms conventional detection schemes.