Samsung Offers 5G Operational Efficiency through Intelligent Energy Saving Features

There is a close correlation between network data traffic and energy consumption—energy usage surges proportionally to traffic growths. According to a study on Korea’s 5G mobile traffic by Electronics and Telecommunications Research Institute (ETRI), 5G data traffic has been growing exponentially since its commercialization. The study predicts that by the second half of 2024, 5G data traffic will exceed that of 4G by more than eight times. As 5G services mature, operators will continue to demand more ways to maintain low network energy consumption.

The good news is that there is a myriad of potential opportunities to save more power in 5G networks than in previous generations of networks. We can take advantage of the fluctuating traffic demands to control network power usage. The figure below illustrates the daily pattern of mobile traffic volume per hour in a typical residential area. The mobile traffic load in the evening is high, while traffic load in the early morning decreases significantly. Network traffic loads can vary depending not only on the time of the day but also on location. Since traditionally, office parks or shopping malls are crowded during the daytime, traffic loads tend to spike during those hours. By applying the right energy saving features, we can help operators control their power usage based on the varying traffic patterns.

Samsung has been researching and developing its software features to cut down energy consumption in RAN products including massive MIMO radios and basebands for both of 4G and 5G networks. There are various ways to save power usage such as temporarily controlling the transmit module, turning off unused carriers, limiting partial transmit paths or controlling the overall radio transmit power, among others. What are some of our key features that will drive energy savings?

• Dynamic Power ON/OFF: This feature controls the power usage of an RF transmit module. RF transmit module stays in stand-by mode when it is not transmitting symbols that carry signals or channels. In other words, the transmit module can be turned on/off depending on the presence of a signal or a channel. In a 4G network, there are more Cell-specific Reference Signals (CRSs), which require constant transmission of symbols. On the other hand, in 5G networks, the transmit module can be switched to stand-by mode more frequently than in 4G networks because 5G does not transmit any CRSs. Since there are more opportunities to turn off power in 5G networks, this feature is an effective energy saving source for 5G.

• Carrier ON/OFF in Multi-Carrier Sites: Most operators offer 4G and 5G services through multiple carriers over multiple frequency bands. In order to meet the high capacity demands in overly crowded areas, all of the available frequency bands get fully utilized. However, in particular places or times of the day when the mobile traffic demand is significantly lower—e.g. inside a subway station after operation hours—a single carrier band may be sufficient to maintain the coverage, enabling the rest of the carriers to be turned off temporarily. This helps networks to avoid unnecessary power consumption for both radios and basebands.

The power consumption of a site is proportional to the site’s RF signal radiation strength. The figure below shows the amount of energy saved, depending on the downlink traffic load. 

- When downlink traffic load is at maximum, the amount of power consumption is also at its maximum, defined as, P_MAX. 

- When there are no UE-specific downlink signals transmitted, the base station stays in stand-by mode with low power utilization, defined as P_IDLE. 

- When the energy saving features are turned on, power consumption is in energy saving mode, defined as P_ES. 

As shown in the figure, the lower the download traffic load, the higher is the amount of energy saved.

According to our predictive modeling based on the traffic volume expected for the first half of 2021, applying the energy saving features to 3.5GHz massive MIMO radios could potentially save approximately 16% of energy use.

In order to maximize energy efficiency, there are some factors operators need to consider:

(1) Which sites are appropriate for the energy saving features?

(2) Which time zones are appropriate for the energy saving modes?

Samsung’s intelligent management system provides the option to set up the KPI thresholds for the entry and exit of the energy saving features, which enables customized modification on a per cell basis. We plan to implement automation and Artificial Intelligence (AI) to our energy saving features to avoid human errors and to optimize KPI thresholds per cell. By learning from the selected KPIs and statistics, the AI-based energy saving features can arrange the optimal operation scenario per cell, maximizing efficiency, and also returning the cell back to its normal service mode in response to unusual traffic demands.

With new 5G use cases increasing the capacity of the networks, operators are more mindful of their network energy consumption. By bringing intelligence to our 5G solutions, Samsung will continue to deliver innovative and smart ways to ensure energy efficiency in 5G network operations.