cognitive radio

wireless communications

mobile networks

radio access

use cases

power allocation

cellular networks

mobile network

access network

IEEE communications standards magazine

To keep supporting next-generation requirements, the radio access\ninfrastructure will increasingly densify. Cell-free (CF) network architectures\nare emerging, combining dense deployments with extreme flexibility in\nallocating resources to users. In parallel, the Open Radio Access Networks\n(O-RAN) paradigm is transforming RAN towards an open, intelligent, virtualized,\nand fully interoperable architecture. This paradigm brings the needed\nflexibility and intelligent control opportunities for CF networking. In this\npaper, we document the current O-RAN terminology and contrast it with some\ncommon CF processing approaches. We then discuss the main O-RAN innovations and\nresearch challenges that remain to be solved.\n

Cell-Free mMIMO Support in the O-RAN Architecture: A PHY Layer Perspective for 5G and Beyond Networks