Challenge for Operators

Mobile operators are under pressure. The 5G revolution is in full flow and is delivering significantly enhanced customer experiences for many users, who are now able to enjoy faster data speeds, reduced busy-time congestion and an enhanced range of services. This is leading to improved ARPUs for some operators, although for many revenue per user remains stubbornly flat.

And the migration is also adding cost pressures. New spectrum is often costly, depending on the system used to allocate it. The costs of building new networks is a further concern. Then the operating costs of new networks are also considerable. While 5G typically offers more data throughput per kW of power, the much greater overall throughput means energy use has increased – and this at a time when energy costs have been rising. For a typical operator, energy costs can account for between 20% and 40% of network operating costs. And beyond the cost to the business, operators are bound to also consider their social responsibility at a time of growing concern about the impact of energy use on the environment.

But does it have to be this way? Are there technical solutions that can help operators deliver higher network performance while also managing operating costs?

The simple answer is that there are solutions available and this report will consider those from Huawei.

Huawei has developed a series of innovative technologies that it is bringing to market with a simple and easily understandable phrase – zero bit, zero watt. So let’s dig into what this means and what the implications are for mobile operators able to take advantage of these new technologies.

What is zero bit, zero watt?

The proposition is straightforward, when the network is carrying no data, it will consume no power. It sounds easy but it’s not. In conventional networks, even when there is no traffic on a base station, it is still consuming a lot of power. There have been available techniques to reduce power consumption during low traffic periods, but these have been fairly blunt tools based on scheduling downtime that results in reduced performance for defined time periods. For many operators it isn’t possible to significantly reduce power consumption on the network due to equipment and performance constraints.

Zero bit, zero watt capability is the first of its kind to achieve almost zero energy consumption in idle state based on a 99% deep shutdown and then fast wakeup of equipment. By reducing network-wide energy consumption by over 35%, it encourages operators to widely deploy 5G with fewer concerns over power consumption.

Huawei’s zero bit for zero watt approach combines multiple techniques that combine to reduce power consumption dynamically, while also increasing the performance experienced by users. Huawei has achieved advances in several areas that combine to enable the power saving and performance increases. These include:

Materials – dynamic energy saving can cause significant changes in temperature within critical modules. This can result in issues such as condensation and thermal expansion and contraction that impacts the reliability of components. Huawei uses innovative materials that absorb moisture as condensation builds-up and then re-emits it when temperatures rise during times of higher power usage or when environmental conditions increase the ambient temperature. In addition, Huawei uses solder bonds that are designed to flex with wide temperature variations. This prevents mechanical stress that can cause failures and which contributes to an industry average failure rate of around 2%. By contrast, Huawei’s failure rate is 0.01%.

Architecture – Speed is essential when dynamically managing the network for energy optimisation. Huawei uses an architecture called iPowerStar that uses a Mobile Intelligent Engine to orchestrate energy savings based on deep understanding of traffic patterns, combined with the energy-saving features. This then flows to and from the key components to support rapid shutdown on varying network loads. This can be managed at the symbol, channel or entire carrier level, within milliseconds. And this level of power management granularity is achieved by atomising the power control and interface circuits so components can be managed on demand. The standard industry approach shuts down entire modules which limits the speed at which they can be brought back on line. In Huawei’s solution, for example, the power amplifier (PA) architecture achieves a 50% higher efficiency than the industry average in medium- and low-load scenarios.

Algorithms – Using innovative materials and architectures is only part of the story. Huawei’s solutions are also smart. Huawei has applied more than 10 years’ experience and around 700 mathematicians to optimise its software. This enables Huawei to uniquely overcome issues of power interference at channel edges. In addition it is the first in the industry to achieve service-based inter-site Transmission Time Interval (TTI) level power coordination by introducing intelligent grids and inter-site distributed energy efficiency gradient algorithms, minimizing inter-site interference and improving user experience by as much as 30%. It’s also the first to implement network-level online fast iterative simulation of multi-dimensional models (coverage, experience, and energy consumption) enabling 24/7 accurate collaboration between performance and energy savings, this means it can achieve around a 30% better user experience and a 30% lower energy consumption than the industry average.

For an operator using multiple frequency bands on a single site, zero bit for zero watt algorithms can progressively shut down different frequency bands until only, say, the 800MHz part of the network is operating, with other frequencies in a dormant state.

In addition, the zero bit, zero watt approach helps operators deliver superior performance, simplified deployments and energy-saving infrastructure when building 5G multi-band networks.

Deployments and current results

Huawei has achieved significant deployments already with more than 30 operators worldwide enabling over 40,000 sites. The ability to achieve a 99% deep shutdown of equipment reduces the power consumption of modules in idle state from hundreds of Watts to almost zero. When the service load on a live network reaches a pre-defined threshold, RF modules automatically wake up quickly, guaranteeing the service experience.

Different geographical locations provide different traffic profiles.

• Business districts show typical daily tidal flows of traffic with high demand during the business day but falling off steeply during the night when traffic is low. Typical power savings in these areas are between 10% and 20%.
• Sub-urban areas have lower overall demand with sparser network coverage and can achieve even higher energy savings. A network in China obtained up to 40% energy savings, while one in Kuwait managed over 20%.
• Residential areas tend to have higher traffic demands in the evening but need balanced service levels throughout the day. A deployment in Cambodia has achieved up to 15% energy savings.

Various deployments show the potential to save significant energy costs while optimizing the customer experience.

• China Mobile: China Mobile has deployed the solution on its commercial networks. Statistics over the first seven days after deployment showed that RF modules automatically entered ultra-deep dormancy during off-peak hours, with a power consumption of just 5W. The average daily dormancy duration reached 9.5 hours, reducing energy consumption by 38%. In addition, RF modules can quickly respond to user service requirements, which improves user experience by 12% compared with scheduled restarts.
• Orange Group: Orange tested the solution for equipment-level energy saving in Romania. The result showed that the average daily energy consumption was reduced by 30% and the user throughput remained stable throughout a month long test period. Next generation AAUs will provide even greater energy savings and even faster wake-up speeds.
• The operator also tested the solution for network-level energy saving in Spain. The result showed that the all-day energy saving improvements reached 15% without affecting user experience.
• Zain Kuwait: Compared with conventional energy saving methods, the solution supports more flexible energy saving policy orchestration based on stable network KPIs, achieving an upgrade from off-peak to all-day energy saving. Zain has used the solution to achieve up to 22.9%, 12.9%, and 8.9% energy savings in its 5G, 4G, and 2G networks, respectively.
• Germany: a test was conducted around Hamburg on a cluster of 38 typical sites across city, sub-urban and rural areas with varying frequency bands deployed in each area. Compared to the baseline the traffic volume increased almost 10%/day during the test period. The power saving gain achieved was around 7% per day with energy saving benefits estimated to be 8-10%. KPIs and user experience remained stable throughout the test phase. Extrapolating the energy savings to the whole network based on using the cluster savings as a reference translates to a net benefit of at least €4 million/year.

Summary and conclusion

Zero Bit for Zero Watt from Huawei is a comprehensive set of solutions that are able to help operators solve several significant issues simultaneously. While 5G delivers a premium user experience, its high bandwidth and Massive MIMO also increases power consumption. Huawei's zero bit, zero watt solution enables modules to consume almost zero power under low load, reducing resource waste and operating expenditure. The solution also continuously minimizes energy consumption without compromising user experience under medium and high loads. It can serve as a key tool for operators to minimize energy consumption with the dual benefits of reduced operating costs and enhancing environmental responsibility.

This article is sponsored by Huawei.