Understanding 5G New Radio in Non-standalone Operation Applications
The 5G New Radio platform is continuing to evolve. A clear understanding of 5G goals, technical terms, and technology will allow designers to imagine new use-cases for the nascent network.
5G New Radio (NR) is still a growing technology, even though its development dates back the better part of the last decade. The development of 5G NR is following the standards set forth by 3GPP in a series of ‘releases.’
There are three leading 5G technologies: enhanced mobile broadband (eMMB), massive machine-type communications (mMTC) & ultra-reliable low latency communications (URLLC).
Additionally, there are two deployment formats for the 5G NR: non-standalone (NSA) and standalone (SA). Currently, mobile network operators (MNOs) are operating NSA-style 5G, which connects to the long-term evolution (LTE) evolved packet core (EPC) 4G core network.
NSA applications utilize LTE evolved packet core backhaul. Image used courtesy of Qualcomm
Today, this article will cover the basic applications expected to manifest on a 5G network. These applications range from consumer-facing technologies to industry 4.0 with URLLC and the deployment of machine networks with mMTC.
5G Networks Will Connect Everything Together
Although developed as a trinity specification for connecting different network elements for different purposes to a single core network, true 5G will have overlapping application requirements.
eMBB applications will use URLLC for real-time processing, and machine-type communications will also require URLLC to facilitate in-the-moment decision-making.
As seen below, several domain crossings will occur, which must incorporate at least two of the three main 5G technologies.
The generalized spectrum of 5G applications. Image used courtesy of ublox
In many ways, the glue that will hold 5G together is ultra-reliable low latency communications. When considering the divergent power requirements and data throughput differences between eMMB & mMTC, there is not a significant overlap between these two technologies.
Now let's dive into the applications for eMMB.
5G NR Applications for eMMB
Possibly the most exciting application offered by eMMB is the ability to have fixed wireless access (FWA) points in both remote or rural areas and high-density locales, offering speeds comparable to fiber connections without the infrastructure costs.
Connecting an FWA point for 5G UE to 4G EPC backhaul. Image used courtesy of Metaswitch
Beyond opening up new markets of internet subscribers, eMMB will help to enable applications requiring high throughput such as video monitoring & surveillance, video conference calls anywhere, and support the growing cloud-based gaming environment.
Potential 5G NR Deployments For mMTC
Officially, 3GPP supports two deployment technologies for mMTC, including Narrowband-IoT (NB-IoT) and LTE-M. These are based on the low-power wide-area (LPWA) network with one million devices per square km rated density.
Various mMTC applications can include low transmission rate remote monitoring of industrial and civil infrastructure, as wells as asset tracking & logistical analysis, with operational lives measured in years.
Beyond 3GPP, ETSI released DECT-2020 last year to support mMTC and IoT local wireless networks within the NR frequency bands supporting mesh, star, and point-to-point topologies.
DECT-2020 cluster mesh topology with fixed and portable terminations. Image used courtesy of Kovalchukov et al
Reportedly, DECT-2020 multi-hop deployments can be used in high-density applications, resulting in improved energy efficiency and reduced packet loss rates over single-hop architectures (UE to base station).
5G NR Technologies For URLLC
Despite being the glue that will likely hold 5G NR together, URLLC is a tall order. The end goal of 0.5 to 1 ms latency targets for real-time decision making, coupled with five-nines uptime, is difficult to achieve because low latency and reliability are in opposition to each other.
Moving from 4G LTE, 3GPP has set out several changes in 5G to assist in achieving lower latency communications, two of which are flexible numerology and sub-slot transmission.
Flexible numerology allows for variable orthogonal frequency-division multiplexing (OFDM) symbol rates to range from 71.35 µs down to 4.46 µs. Compared to LTE, with its fixed symbol rate (71.35 µs), variable symbol rates aim to reduce transmission latency via symbol length.
Slot-based transmission has been improved to allow for the sub-slot transmission of packets, thereby reducing the time it takes for packets to be transmitted.
NSA Sets the Stage for 5G Standalone
The rollout of 5G end-to-end connectivity will take time and must respect the infrastructure investment placed on existing 4G networks. The non-standalone architecture facilitates both of these objectives by enabling dynamic spectrum sharing (DSS).
Right now, the consumer-facing aspects of eMMB are providing MNOs the financial resources for continued development of their 5G infrastructure and allow for the eventual transition off of the 4G EPC network backhaul.
Industry 4.0 will follow, and URLLC & mMTC applications could be seen, which are still in the early development stages, start to mature and release.
However, many of these applications will hinge on future releases of the 3GPP NR standards, the proliferation of mmWave hardware, and the deployment of 5G NR standalone core networks.