BBU

BBU is an acronym that can refer to several concepts across industries. The two most common meanings are Baseband Unit, a component in wireless networks, and Battery Backup Unit, a power-protection device used in data centers and telecom infrastructure.

In telecommunications, a Baseband Unit (BBU) provides processing for baseband signals and control functions. In traditional cellular systems, the BBU houses the baseband processor, MAC layer functions, and interfaces to the core network, while the Radio Unit (RRU/RRH) handles radio transmission. The BBU connects to remote radio heads via fronthaul links such as CPRI or eCPRI. In 4G LTE, this architecture is common; in 5G, functional splits are evolving toward Distributed Units and Central Units, with the BBU term retained in some vendor documentation to indicate centralized processing.

In power and data infrastructure, a Battery Backup Unit (BBU) is a module that provides emergency power during outages and supports orderly shutdowns. BBUs are used as part of uninterruptible power supply systems in data centers, telecom shelters, and industrial equipment. They contain rechargeable batteries (commonly lithium‑ion or lead‑acid) and a battery management system. Runtime depends on load and battery capacity; aging batteries reduce available capacity and require replacement or maintenance. BBUs are designed to bridge short outages and to protect equipment from data loss or damage.

Other uses of the acronym exist in industry-specific contexts, but Baseband Unit and Battery Backup Unit cover the primary technical senses of BBU.