Michał Maternia

Scenarios for 5G mobile and wireless communications: the vision of the METIS project

METIS is the EU flagship 5G project with the objective of laying the foundation for 5G systems and building consensus prior to standardization. The METIS overall approach toward 5G builds on the evolution of existing technologies complemented by new radio concepts that are designed to meet the new and challenging requirements of use cases todays radio access networks cannot support. The integration of these new radio concepts, such as massive MIMO, ultra dense networks, moving networks, and device-to-device, ultra reliable, and massive machine communications, will allow 5G to support the expected increase in mobile data volume while broadening the range of application domains that mobile communications can support beyond 2020. In this article, we describe the scenarios identified for the purpose of driving the 5G research direction. Furthermore, we give initial directions for the technology components (e.g., link level components, multinode/multiantenna, multi-RAT, and multi-layer networks and spectrum handling) that will allow the fulfillment of the requirements of the identified 5G scenarios.

On the performance gain of flexible UL/DL TDD with centralized and decentralized resource allocation in dense 5G deployments

Ultra dense small cell deployments and a very large number of applications are expected to be the essential aspects of the newly emerging 5th generation (5G) wireless communication system. To match the diverse quality of service requirements imposed by a variety of applications, dynamic TDD is proposed as a solution by enabling flexible utilization of the spectrum for uplink and downlink of each cell. In this paper, the system performance of flexible (dynamic) TDD is compared to a fixed portioning of resources for uplink and downlink. Further, the degree of centralization for resource management is investigated in the context of dynamic TDD, because multi-cell scheduling will be important for the design of 5G ultra-dense network architecture. The results show that dynamic TDD is indeed a very promising option for 5G networks, and substantially decreases packet outage delays. We find that the performance gap between centralized and decentralized scheduling is small in case of planned deployments. However, centralized scheduling may be beneficial in certain dynamic TDD deployment scenarios with a very asymmetric access point distribution.

Modeling of Wi-Fi IEEE 802.11ac Offloading Performance for 1000x Capacity Expansion of LTE-Advanced

This paper studies indoor Wi-Fi IEEE 802.11ac deployment as a capacity expansion solution of LTE-A (Long Term Evolution-Advanced) network to achieve 1000 times higher capacity. Besides increasing the traffic volume by a factor of x1000, we also increase the minimum target user data rate to 10Mbit/s. The objective is to understand the performance and offloading capability of Wi-Fi 802.11ac at 5GHz. For the performance evaluation of Wi-Fi, we propose a novel analytical throughput model that captures both key 802.11ac enhancements and multi-cell interference. We provide a quantitative evaluation of large-scale indoor Wi-Fi 802.11ac deployment in a real urban scenario by extensive simulations. We conclude that deploying indoor Wi-Fi access points in almost every building is essential to carry the x1000 traffic volume and ensure a minimum user data rate of 10Mbit/s.

Heterogeneous LTE-Advanced Network Expansion for 1000x Capacity

This paper studies LTE (Long-Term Evolution)-Advanced heterogeneous network expansion in a dense urban environment for a 1000 times capacity increase and a 10 times increase of the minimum user data rate requirements. The radio network capacity enhancement via outdoor and indoor small cell densification and utilization of the higher frequency bands has been investigated. As the baseline, we assume a full LTE-Advanced network deployment. Rather than looking at peak data rate, we focus on the end-user experience defined as 90% coverage at a minimum user data rate. We conclude that the 1000 times network capacity increase together with the 10 times increase of minimum user data rate can be reached by LTE-Advanced deployment with approximately 10 times more outdoor micro sites and 100 times more indoor femto cells with respect to the number of macro sites. In terms of spectrum requirements, we have increased the total amount of downlink spectrum to a total of 300 MHz by re-farming spectrum and adding new spectrum in 3.5 GHz band. We conclude that new spectrum at 3.5 GHz is essential to reach the set target network capacity.

Heterogeneous Network Evolution Studies for a Dense Urban High Rise Scenario

This paper studies the capability of Long-Term Evolution-Advanced (LTE-A) together with WiFi 802.11ac to accommodate the traffic growths of 80x, 500x and 1000x in a high rise building scenario. It provides a guideline on the configuration of the spectrum and the best deployment options for the evolution of the heterogeneous network in order to enhance the capacity for the coming years. The results indicate that, although the deployment of outdoor cells is very important to increase the capacity of the current networks, the expansion with indoor small cells is essential in order to provide coverage and capacity for the future wireless service consumers, specially those located in the high rise buildings.

On performance of long term HSPA evolution: Towards meeting IMT-Advanced requirements

In this paper, evaluation of HSPA radio technology is provided with the reference to IMT-Advanced requirements. Recent technological advancements are included to verify if HSPA is capable of meeting these requirements. Extensive system-level simulation campaigns are carried out, which shadow IMT-A performance evaluation guidelines and suggested test environments specifications. Respective results are analyzed in the context of spectral efficiency, VoIP capacity and high speed mobility of IMT-A requirements. The presented results indicate that although a single strongly interference-limited environment is unlikely to pass stringent IMT-A spectral efficiency criteria, overall all the IMT-A test requirements are passed.

Resource and Mobility Management in the Network Layer of 5G Cellular Ultra-Dense Networks

The provision of very high capacity is one of the big challenges of the 5G cellular technology. This challenge will not be met using traditional approaches like increasing spectral efficiency and bandwidth, as witnessed in previous technology generations. Cell densification will play a major role thanks to its ability to increase the spatial reuse of the available resources. However, this solution is accompanied by some additional management challenges. In this article, we analyze and present the most promising solutions identified in the METIS project for the most relevant network layer challenges of cell densification: resource, interference and mobility management.