How 5G will deliver more for less
With faster speeds and ultra-low latency, the new 5G radio networks are already operating in multiple markets, including automotive, industrial, medical and defense. This article describes how 5G combines several low-power strategies to deliver the best overall performance to meet today’s green movement and provide an ideal solution for 21st-century radio challenges.
But first, what is 5G?
5G or fifth-generation radios introduce the next level in electronic communication. The revolutionary and innovative first generation (1G) radio networks only offered customers basic analog voice services. The 2G network added secure voice and text services but with limited data services. With 3G radio communications came a theoretical peak download speed of 7.2 Mbps with HSPA, bringing internet access and file-sharing capabilities. With the 4G radio networks came a new technology – Long Term Evolution (LTE), which reduced data transfer latency. The reduction of latency was critical as the number of users started to put the networks under pressure.
While these older solutions work, they show limitations in speed, data and power. The evolutionary path means each generation has brought us closer to the 5G initiative, which uses New Radio or NR technology. It delivers lower latency, better power efficiency, and expanded transmission channels.
5G wireless networks potentially enable universal sensing, supporting a multitude of connected devices. These networks will process vast amounts of data, which will be mined to provide in-depth information.
The 5G radio networks pose primary frequency domain challenges and architecture changes. The 5G frequency ranges comprise low-band (sub-6 GHz), and high-band millimeter wave (mmWave, 24 GHz to 100 GHz range). The circuit architecture challenges lie in increasing the number of channels across the network while managing the system-level power.
Compared to 4G systems, 5G systems are hundreds of times faster, with 10 times lower latency and higher network density that can support billions of devices. For example, downloading a high-definition film over 4G would require tens of minutes, but over a 5G interface the download would take just a few seconds. The latency for 4G systems is in the region of 50 to 200 milliseconds, close to a human's visual stimuli reaction of 250 milliseconds. With 5G, latency drops to as little as 1 millisecond. However, the combination of increased speed and additional devices/users dramatically impacts system power.
Faster, more connections
5G will support multiple consumers and equipment channels with one radio network.
5G’s innovation in power
Each successive generation in mobile technology extends coverage and services to more devices. Although the device power consumption of consecutive generations is lower, this coverage and device extension cause a rise in each generation’s energy consumption. With the addition of users and equipment, the status quo energy requirements could skyrocket, threatening to limit progress.
5G is fundamentally different from previous radio technologies. This network generation is more than just a high-speed radio internet service, as it helps to accelerate the digitization of industries and devices. 5G energy consumption per unit of data (watt/bit) is much less than 4G because of 5G’s power initiatives. Typically, 5G networks are 90% more energy efficient per traffic unit than 4G networks. On the other hand, the general power consumption from increased transmission traffic is two to four times greater than 4G, posing unprecedented challenges for 5G infrastructure construction.
To address this, 5G employs four power reduction strategies to bring radio technology into the 21st century:
- Higher data rates
- Improved timing algorithms and sleep modes
- New network protocols
- Network hardware modernization
Higher data rates
5G networks have higher data throughput and lower packet latency. At higher data rates, the transfer of data requires a shorter period. These shorter periods create potential for extended idle periods between the client and base station. As a 21st century architecture, these idle periods allow for longer sleep mode periods, which has a positive impact on the overall average power consumption.
Timing algorithms and sleep modes
As shown in the figure below, the 4G LTE channel typically operates in an always-on signal transmission mode, sending cell-specific reference signals (CRSs). The CRS ensures cell coverage and a good user link. The CRS algorithm has less than one millisecond between each signal transmission, providing little chance for the base station to enter a sleep mode. Consequently, this algorithm offers limited possibility for LTE energy savings (upper trace). In contrast, the NR (lower trace) requires far fewer always-on transmissions. The result is more prolonged and deeper sleep periods when the data transmissions are little or none. This timing approach has a positive impact on the overall network energy consumption.
New Radio’s timing approach: A positive impact on overall network energy consumption
The Long Term Evolution (LTE) idle mode power (upper trace) is busy performing always-on transmission activities. In contrast to the LTE curve, the New Radio (NR) idle mode power curve is approximately four times faster and only performs essential LTE actions.
New network protocols
The new 5G network protocols reduce power consumption with compressed data packet payloads which, in turn, also reduces the traffic volume. Additionally, the system separates the user and controls traffic to create a reduction in network chatter. The traffic reduction and control packet elimination lead to substantially more idle periods and more extended sleep mode periods.
The Multipath Transmission Control Protocol (MPTCP) is an ongoing effort to support Transmission Control Protocol (TCP) connections. MPTCP increases network efficiency and reduces packet retransmits. All these protocols work collaboratively to reduce overall energy consumption.
Hardware modernization
The 5G standard now includes the critical technical enablers for better energy performance: ultra-lean design and massive multiple-in and multiple-out (MIMO). Massive MIMO and beamforming techniques increase network coverage and provide higher capacity to address the number of site installations required. Beamforming is being used in cellular base station traffic-signaling systems and identifies a particular user’s most efficient data-delivery route. In the process, beamforming reduces nearby user interference. There are several ways to implement it in 5G networks depending on the situation and the technology. These enhancements provide extended network coverage in a sustainable and resource-efficient way, reducing the total cost of ownership for service providers.
All in all, these power reduction strategies for 5G working together will truly usher in 21st Century Radio.
