Milos Tesanovic

5G Radio Access Network Architecture: Design Guidelines and Key Considerations

While there is clarity on the wide range of applications that are to be supported by 5G cellular communications, and standardization of 5G has now started in 3GPP, there is no conclusion yet on the detailed design of the overall 5G RAN. This article provides a comprehensive overview of the 5G RAN design guidelines, key design considerations, and functional innovations as identified and developed by key players in the field.1 It depicts the air interface landscape that is envisioned for 5G, and elaborates on how this will likely be harmonized and integrated into an overall 5G RAN, in the form of concrete control and user plane design considerations and architectural enablers for network slicing, supporting independent business-driven logical networks on a common infrastructure. The article also explains key functional design considerations for the 5G RAN, highlighting the difference to legacy systems such as LTE-A and the implications of the overall RAN design.

Agile resource management for 5G: A METIS-II perspective

An explosive growth in the demand for higher data rates and capacity along with diverse requirements set by massive and ultra-reliable machine-type communications are the main drivers behind the development on new access technologies as part of the fifth generation (5G) networks. Currently, different air interface (AIF) and/or AIF variants, optimized based on the frequency band of operation and use case, are envisioned for such a network. Developing an agile resource management framework for 5G networks is one of the main goals of the METIS-II project. The METIS-II project builds strongly upon the EU flagship project METIS, which has laid the foundation of 5G. This framework will take into account the multi-link and multi-layer constraints currently envisioned for 5G. In this paper, we provide our first insights into agile resource management and the associated synchronous control functions. We will discuss the essential building blocks in terms of technology enablers and their mapping to 5G services and deployments. The introduced agile resource management framework for 5G is expected to enable enhanced interference management, dynamic traffic steering, fast radio access network (RAN) moderation, efficient context management, and optimized integration with legacy networks.

mmWave-Based Mobile Access for 5G: Key Challenges and Projected Standards and Regulatory Roadmap

Wireless communication using millimetre-wave (mmWave) systems, i.e. systems operating at frequencies between 30 and 300GHz, has long been used for point-to-point radio links, wireless backhaul, and more recently fixed wireless access as well as LAN communication. This notwithstanding, the use of this vast and diverse band and the adjacent lower bands (more specifically, the 6-100GHz region which this paper focuses on and collectively refers to as mmWave) for mobile access has until recently been thought impossible due to technical as well as regulatory constraints. Recent successful super-fast demos which use the mmWave technology for mobile access have pushed the boundaries and made the use of 6-100GHz bands for mobile access perhaps the most talked-about development on the road to 5G. This paper assesses the relevant regulatory and standardisation challenges (in addition to providing a critical summary of the technical ones). By examining various proposed 3GPP timelines, the ITU work plan, ETSI ISG mWT, NGMN, and 5G-PPP activities (among others), we show that a picture is indeed emerging of regulatory and standardisation plans, and we draw up a projected industry roadmap - still with a lot of unknowns on the road to mmWave access, which we also identify. This roadmap and the complex interplay of different actors which we also capture will help various research activities across the world in aligning their work with the emerging standardisation and regulation framework. We additionally contribute some new insight into integration of mmWave communications into various proposed 5G architectures.

FQAM-FBMC design and its application to machine type communication

In this paper, we propose a novel waveform design which efficiently combines two air interface components: Frequency and Quadrature-Amplitude Modulation (FQAM) and Filter Bank Multicarrier (FBMC). The proposed approach takes the unique characteristics of FQAM into consideration and exploits the design of prototype filters for FBMC to effectively avoid self-interference between adjacent subcarriers in the complex domain, thus providing improved performance compared with conventional solutions in terms of self-interference, spectrum confinement and complexity with negligible rate loss. The resulting waveform properties are proven in this paper to be particularly suitable for Machine Type Communications (MTC) devices due to the observed reduced PAPR and lowered energy consumption. MTC has created a new eco-system that gives rise to a plethora of interesting applications and new business opportunities in the fifth-Generation (5G) mobile system and services — the enabling technology for the emerging paradigm of Internet of Things (IoT).

Emerging network architecture and functional design considerations for 5G radio access

While there is already a common understanding of the services, which 5th generation 5G mobile communications systems should support, and the key technology components needed to achieve this, there is still the need for further clarification and consensus among key players on the overall 5G radio access network RAN architecture and its detailed functional design. The 5G public private partnership 5G PPP project METIS-II has the objective to foster exactly this consensus building before and in the early days of the standardisation work for 5G. This paper lists the 5G RAN design requirements as identified in the project and summarises the latest considerations of METIS-II on the air interface landscape in 5G, the envisioned logical RAN architecture and related aspects, as well as key functional design considerations in 5G, which have found wide endorsement within the project. Copyright

Interference management via space and frequency domain resource partitioning

One key requirement for the fifth-Generation (5G) mobile system is the enhancement of cell edge user performance to ensure that every user is supported with consistent experience anywhere in the network. An active interference design to improve anywhere performance, particularly in the low SINR regime, can be achieved by applying a recently proposed new type of modulation scheme, frequency quadrature-amplitude modulation (FQAM), which could change the distribution of interference and therefore improve channel capacity. In this paper, a resource partitioning scheme to support FQAM in interference intensive scenarios is proposed. The proposed scheme slices radio resources into orthogonal parts for QAM and FQAM, respectively, along two different resource dimensions, namely, space and frequency. This can be achieved by incorporating advanced beamforming algorithms, e.g., full-dimension (FD-MIMO), and performing a frequency-based split of FQAM resources to effectively improve the data rate of the edge users experiencing heavy interference. Two resource partitioning mechanisms are proposed followed by complexity analysis. Evaluation results on both space and frequency-based FQAM interference management are presented, showing significant performance improvements when compared to the regular QAM modulation.

Design framework and suitability assessment proposal for 5G air interface candidates

This paper proposes a unified way of describing 5G air interface (AI) design proposals using a 5G service/frequency map based on work carried out as part of 5G-PPP/H2020 project “METIS-II”. It then crucially proposes a design framework and suitability assessment process for 5G AI candidates. The proposed assessment methodology focuses on “harmonization Key Performance Indicators, or KPIs” and how to measure them (qualitatively / quantitatively). The paper proposes that evaluation of 5G AI candidates should, in addition to performance, include the “extent of harmonization”, which is defined in this paper. The case is argued that these harmonization KPIs are essential when assessing new 5G AI technologies. Additionally, an initial overview of different User Plane aggregation approaches is provided. We then discuss the types of Application Program Interfaces (APIs) which may need to be offered to higher layers, as well as a broad set of 5G Control Plane features and how AI considerations could take these into account.