Open RAN enables intelligent, data-driven RAN optimization and control, according to an ABI Research analyst
Whether improving the power efficiency of mobile networks is truly the “highest priority” for operators, as Saqlain Ali, senior analyst at ABI Research, claimed at Open RAN Forum, it can’t be denied that power reduction practices are top of mind across the telecom industry. Furthermore, the radio access network (RAN) has become a particular target for energy reduction because it’s considered the most “power hungry component,” consuming as much as 80 to 90% of the total power in a mobile network. Therefore, Ali stated, the trend towards virtualized, as well as more open and disaggregated, RAN must be considered when discussing telco network sustainability.
“In traditional networks, the radio units and baseband units are integrated together,” explained Ali, adding that this “restricts openness” and leaves “no room for innovation.” Virtualized radio access networks, he continued, may lead to more innovation because the baseband unit is virtualized, but it is Open RAN that provides a virtualized and segregated environment for the baseband units and for the radio units. “It has room for innovation and… open interfaces to bring intelligence into the network, and since they are virtualized, there is room for energy efficiency,” he said.
Thanks to the introduction of the RAN intelligent controller (RIC) and xApps and rApps, he continued, the energy efficiency of the RAN can be greatly improved. The RIC is a central software component of the Open RAN architecture, and by supporting network automation — whether the development of energy saving features or automatically detecting anomalies — it provides a higher degree of energy optimization. “The introduction of RIC… can provide policy-based guidance to optimize the control and control the RAN elements such as O-CU [O-RAN Centralized Unit], O-DU [O-RAN Distributed Unit] and O-RU [O-RAN Distributed Unit],” Ali stated.
An Open RAN environment can also maximize the power density by utilizing highly efficient semiconductor material, according to Ali. “For example, gallium nitrate can reduce the power and increase the power efficiency up to 40%,” he said. In general, when it comes to silicon, legacy RAN uses application-specific, integrated circuits or system of chips (SOCs), while Open RAN provides more opportunities to use commercial off-the-shelf hardware for conducting the end processing.
The introduction of frontal interface in Open RAN called 7.2x brings additional energy efficiency into the network by using the lower layer of the functional split as compared to the higher layer functional split and provides the option to offload some of the complex processing components from O-RU to O-DU. And finally, the centralization of the CU (Centralized Unit) and DU (Distributed Unit) will also improve energy efficiency because it means fewer appliances are needed at the cell site and there is a lower real estate cost for the operator.
In summation, Ali stated that legacy RAN environments have limited reconfigurability and coordination, which prevents optimization and control of the RAN. The open interfaces of Open RAN, on the other hand, enable intelligent, data-driven RAN optimization and control, allowing operators to use equipment from multiple vendors and utilize virtualization capabilities to enable efficient execution of sleep mode operations, such as shutting down the power amplifier during peak hours.