English

On the Spatial-Wideband Effects in Millimeter-Wave Cell-Free Massive MIMO

Information Theory 2023-07-07 v1 Networking and Internet Architecture Signal Processing math.IT

Abstract

In this paper, we investigate the spatial-wideband effects in cell-free massive MIMO (CF-mMIMO) systems in mmWave bands. The utilization of mmWave frequencies brings challenges such as signal attenuation and the need for denser networks like ultra-dense networks (UDN) to maintain communication performance. CF-mMIMO is introduced as a solution, where distributed access points (APs) transmit signals to a central processing unit (CPU) for joint processing. CF-mMIMO offers advantages in reducing non-line-of-sight (NLOS) conditions and overcoming signal blockage. We investigate the synchronization problem in CF-mMIMO due to time delays between APs. It proposes a minimum cyclic prefix length to mitigate inter-symbol interference (ISI) in OFDM systems. Furthermore, the spatial correlations of channel responses are analyzed in the frequency-phase domain. The impact of these correlations on system performance is examined. The findings contribute to improving the performance of CF-mMIMO systems and enhancing the effective utilization of mmWave communication.

Keywords

Cite

@article{arxiv.2307.02784,
  title  = {On the Spatial-Wideband Effects in Millimeter-Wave Cell-Free Massive MIMO},
  author = {Seyoung Ahn and Soohyeong Kim and Yongseok Kwon and Joohan Park and Jiseung Youn and Sunghyun Cho},
  journal= {arXiv preprint arXiv:2307.02784},
  year   = {2023}
}