Ensuring The Connected 5G Experience

The world’s demand for data is increasing at an astonishing rate. We need to be connected wherever we are and expect a seamless content rich service. With current devices consuming more and more data and more and more internet enabled devices, the current network infrastructure needs major changes to keep up with demand.

The 5G Solution - More Than Just An Air Interface

With the demand for data set to explode, next-generation 5G networks are being investigated as the solution. Three approaches are being taken towards supporting these huge traffic increases.

Making more efficient use of available frequencies is closely related to speeding-up the physical layer access protocols and wireless access technologies. Increases of efficiency from 2.5 to 10 times have been proposed as targets for 5G waveforms and access methods.

Further proposals for 5G systems aim to increase spectrum efficiency even further by speeding-up existing technologies, using newly opened frequency bands, increasing network density, and support for this is being developed. Rapid developments in CPU processing power and cloud computing are expected to be key elements in deployment of 5G services.

5G will be both an evolution and a revolution. An evolution as mobile evolves to support a wide range of new use cases, and a revolution as the architecture concept is being predicted to completely transform to enable these new use cases.

5G includes the evolution of existing 4G networks that use technologies such as C-RAN and HetNet to increase capacity of existing networks with an affordable cost. But revolution for core architecture to fully use SDN/NFV and network "slicing," the use of a new millimeter wave band air interface for higher capacity, and new architecture/signaling for extreme low latency.

Spectrum

In order to cope with the heavily increasing wireless data traffic in both human- and machine centric communications, radically more spectrum is needed for 5G system operation.

The future development of regulation and technology will create a complex landscape of spectrum availability and access. Multiple frequency bands, subject to different regulation including various forms of shared spectrum, are expected to be available to wireless communication systems. Hence, technology needs to be designed in a flexible way so that it is capable of operating under different regulatory models and sharing modes.

5G Standardization Status in 3GPP

As the radio interface of mobile phones has evolved, it has typically been changed about every ten years, and the 5G (5th Generation) interface is expected to start being used in the 2020s.

Similar to 3G and 4G cases, ITU-R (International Telecommunication Union – Radio communication Study Groups) will request standard organizations to standardize a new interface based on their recommendations for performance and capabilities. After evaluation of each submission, the standards that succeed will be authorized and known as IMT-2020. For the 3G case, WCDMA submitted by 3GPP (the 3rd Generation Partnership Project) and CDMA-2000 by 3GPP2 were authorized as IMT-2000, and for the 4G case, LTE-A (Long Term Evolution-Advanced) by 3GPP and WiMAX-Advanced by WiMAX Alliance were authorized as IMT-Advanced.

5G Waveforms

4G radio access is based on orthogonal transmission for both DL and UL. Orthogonal transmission avoids interference and leads to high system capacity. However, for rapid access of small payloads, the procedure to assign orthogonal resources to different users may require extensive signaling and lead to additional latency. Thus, support for non-orthogonal access, as a complement to orthogonal access, is being considered for 5G. Examples include Non-Orthogonal Multiple Access (NOMA) and Sparse-Code Multiple Access (SCMA)

Superposition encoding example

The 5G radio access technology (RAT) must fulfill the data traffic demand in the coming years with rates above 10 Gbps and sub-millisecond latency. These rates can be achieved, principally, with bandwidths of at least 200 MHz, and using multiple-input multiple- output (MIMO) antenna techniques and interference rejection combining (IRC) receivers. Ideally, the waveform to be used should have good implementation properties, such as limited computational complexity for the generation/detection, limited time/frequency overhead, good localization in time, good spectral containment and simple extension to MIMO, amongst others. It has been shown in 4G that OFDM is suitable for both the good MIMO implementation and also the simple processor implementation in the user devices, and so 5G waveforms are looking to build on this and further evolve OFDM to overcome the current limitations.

Three of the different waveforms that are being considered to be part of 5G

5G Testing Challenges

As the network concepts and technologies develop for 5G, so the corresponding test methods and processes will evolve to match this. Future 5G test methods will need to provide a high confidence to operators that the technology and services are implemented according to specification, and that the quality of service is matching to the requirements of the application or service being delivered.

A fully data-centric 5G network with a very wide and diverse set of applications to test would require a massive effort in standalone testing. Test automation, monitoring and built in test systems will be essential for analyzing properly the performance of such a network. In addition, the emergent solution to use Ultra Dense Networks (UDN) for interconnecting the radio access elements with the backhaul architecture using cloud networks will enable the development of cloud based test services for testing everything from everywhere. So, although 5G will introduce many new test requirements and challenges by the use of SDN/NFV and cloud services, this same technology can also be used for creating new test solutions that address these needs. With this in mind, cloud solutions are seen as both the new demand and the new solution for 5G network testing.

Anritsu can provide a host of solutions to facilitate and assist this research and development to enable the 5G world.