The 3 High Level 5G Use Cases

The International Telecommunications Union (ITU), which defined the 5G requirements specifications, has defined 3 broad use cases for 5G:

• Enhanced Mobile Broadband (eMBB) provides extremely high data rates (of up to 20 Gb/s) and offers enhanced coverage, well beyond that of 4G.
• Massive Machine Type Communications (mMTC) is designed to provide wide-area coverage and deep indoor penetration for hundreds of thousands of IoT devices per square kilometre. mMTC is also designed to provide ubiquitous connectivity with low software and hardware requirements from the devices and will support battery-saving low-energy operation.
• Ultra-Reliable and Low Latency Communications (URLLC) can facilitate critical applications with very demanding requirements in terms of end-to-end (E2E) latency (one millisecond or lower), reliability and availability.

Massive MIMO (for 5G)

Along with beamforming, Massive MIMO is a core 5G technology which can significantly multiply the capacity of a wireless connection – up to 50 times - without using more radio spectrum. MIMO, which stands for Multiple-Input Multiple-Output, enables a single radio channel to simultaneously transmit and receive more than one data signal. MIMO is deployed in LTE networks, which tend to use two or four antennae but Massive MIMO (figure 2), which will be deployed in 5G networks, will use a very high number of antennae – e.g. 32, 64 or rising to 256 or more in future releases.

5G Deployment Options

A mobile network consists of 2 major modules, the Radio Access Network (RAN) and the Core Network. The RAN handles the radio communication between the user equipment (UE), and the core network provides signalling, routing control, user management and other functions. 3GPP, the global organisation tasked with defining the 5G standards, has defined two main alternatives for 5G deployment (figure 3).

• NSA (Non-Stand Alone), where the RAN is 5G New Radio (NR) and the core network is 4G Evolved Packet Core (EPC).
• SA (Stand Alone), where the RAN is 5G NR and the core network is 5G core.

5G NSA enables operators to leverage existing investments in 4G LTE in order to provide certain 5G services. 5G NSA was defined as an option in order to speed up 5G roll-out; operators can bring 5G services to market, generating incremental revenues, whilst delaying the significant investments required by a full-scale 5G roll-out. 5G NSA primarily enables eMBB communications, allowing operators to offer increased data capacity and higher speeds but does not support all of the 5G use cases defined in the 5G specifications (figure 1).

5G SA deployment is required to enable all use cases, adding URLCC and mMTC, thereby supporting a broader range of applications. The 5G core also contains sophisticated network management functionality such as network slicing, a virtual network architecture which allows multiple virtual networks to be created on a shared physical infrastructure. Network slicing is key to delivering the multiple 5G use cases and supporting the associated variety of network functionality and performance requirements.