Publications 2022

Conference articles (9)

Vesa Hytönen, Yrjö Kaipainen, Juha Heiskala, Petri Väisänen, Niko Ohukainen, “System Level Analysis of VoLTE Capacity with Enhanced Machine Type Communication“, The 18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 10-12 October 2022.

In this paper, Voice over LTE (VoLTE) capacity for Enhanced Machine Type Communication (eMTC) is evaluated with system level simulations. The study concentrates on a high signal attenuation scenario which is applicable to various VoLTE indoor use cases, for example voice call connectivity for elevator emergency phone.

Two semi-persistent scheduling approaches are presented and compared that are designed for keeping the end-to-end packet latencies below the delay budget. Due to physical channel repetitions used with eMTC, favorable conditions for semi-persistent scheduling are limited and thus the presented methods combine both semi-persistent and dynamic scheduling.

The results show that signal loss caused by multiple wall penetrations has a significant impact on total VoLTE capacity, with the number of concurrently supported calls in a cell being around 15 with Adaptive Multi-Rate Wideband (AMR-WB) 6.6 kbps codec.

Timo Nihtilä, Tarmo Taipale, “Energy Saving Router Rotation Protocol for DECT-2020 NR“, The 18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 10-12 October 2022.

ETSI DECT-2020 New Radio (NR) is a new flexible radio interface targeted to support a broad range of wireless Internet of Things (IoT) applications. It has been shown to fulfill both massive machine-type communications (mMTC) and ultra-reliable low latency communications (URLLC) requirements for 5th generation (5G) networks.

DECT-2020 NR is an autonomous wireless mesh network protocol where the devices can choose to become routers, forwarding the data of other devices in addition to their own data. Thus, a wireless mesh network does not need separate base stations or a core network architecture to extend coverage. This makes the deployment of DECT-2020 NR networks easy, but with the cost of increased energy consumption in the router nodes. Notably, the same energy consumption is not inflicted upon the non-routing leaf nodes whose operation is on the contrary very energy efficient.

This role-induced disparity in node energy consumption results in the network not using the energy of its devices with maximal efficiency. A method to alleviate this problem could be a network rotation in which the roles of network nodes are periodically rotated and the energy consumption is thus distributed more evenly among the nodes.

In this paper we propose a role rotation protocol for DECT-2020 NR and evaluate its impact to the expected lifetime and the performance of the network by system level simulations.

Mikko Majamaa, Henrik Martikainen, Lauri Sormunen, Jani Puttonen, “Multi-Connectivity for User Throughput Enhancement in 5G Non-Terrestrial Networks“, The 18th International Conference on Wireless and Mobile Computing, Networking and Communications (WiMob), 10-12 October 2022.

To meet the increasing throughput and reliability demands, satellites may be used to complement the Fifth Generation (5G) Terrestrial Networks (TNs). To increase the efficiency of the satellite communications involved, research on bandwidth-efficient techniques is needed. Multi-Connectivity (MC), where a user can be connected to multiple Next Generation Node Bs (gNBs) simultaneously, is one of such techniques.

In this paper, the focus is on MC in NonTerrestrial Networks (NTNs) to improve users’ experienced throughputs. First, a study of relevant specifications and algorithms is conducted. Then, the designed load-aware Secondary Node (SN) addition and traffic steering algorithms are presented and evaluated in a realistic two-satellite Low Earth Orbit (LEO) network scenario. The simulation results indicate that usage of MC can be beneficial in 5G NTNs.

Mikko Majamaa, Henrik Martikainen, Lauri Sormunen, Jani Puttonen, “Adaptive Multi-Connectivity Activation for Throughput Enhancement in 5G and Beyond Non-Terrestrial Networks“, International Conference on Software, Telecommunications and Computer Networks 2022 (SoftCOM), 22 – 24 September 2022.

The Fifth Generation (5G) communications systems aim to serve such service classes as Ultra-Reliable Low Latency Communications (URLLC), enhanced Mobile Broadband (eMBB), and massive Machine-Type Communications (mMTC). To meet the growing requirements posed to mobile networks, satellites can be used to complement the Terrestrial Networks (TNs).

To increase the efficiency of the satellite communications involved, bandwidth-efficient techniques should be used. Multi-Connectivity (MC) is one of such techniques. In MC, a User Equipment (UE), for example, a smartphone, can be connected to multiple Next Generation Node Bs (gNBs).

In this paper, we present an adaptive MC activation scheme for throughput enhancement in 5G and beyond Non-Terrestrial Networks (NTNs).

Ahmed Masri, Jani Puttonen, Jean-François Boutillon, Justine Compagnon, Paul Pontisso, Jonathan Sprauel, “System Level Evaluation of LEO 5G Non-Terrestrial Network for Handheld User Terminals”, The 11th Advanced Satellite Multimedia Conference and the 17th Signal Processing for Space Communications Workshop (ASMS/SPSC), 6–8 September 2022.

System level performance evaluation of non-terrestrial 5G technology is essential to prompt feedback to standardization, the realization of the system, and to the harmonization with the terrestrial 5G.

In this work, we target providing system level performance results for two Low-Earth Orbit (LEO) non-terrestrial 5G constellations with handheld terminals as direct satellite users.

We have simulated and compared the results from two LEO constellations at altitudes of 600 and 1200 km, respectively, and using the 3GPP 5G non-terrestrial network deployment scenarios. Our results show the feasibility of providing services toward handheld terminals from LEO constellation systems.

Frans Laakso, Jani Puttonen, Mikko Majanen, Anastasia Yastrebova, Guray Acar, “Satellite Constellation Network Emulator for End-To-End Performance Evaluation of the Future Satellite Networks”, The 11th Advanced Satellite Multimedia Conference and the 17th Signal Processing for Space Communications Workshop (ASMS/SPSC), 6–8 September 2022.

The importance of satellite systems for telecommunications continues to increase. As there are new launches of satellites every year and many more satellite constellations are currently being under development, the Quality of Service (QoS) and system performance in specific use cases is crucial for many stakeholders.

Simulation tools enable to assess the proposed architecture and carry out extensive performance analysis of the system in relatively early stages of development. The different simulation tools tend to concentrate on certain aspects of system performance, and rarely provide a complete and detailed system analysis.

This article presents a Satellite Constellation Network Emulator (SCNE) tool, which combines the power of Systems Tool Kit (STK) and the flexibility of Network Simulator 3 (ns-3) to allow to study and assess not only satellite propagation characteristics but also protocol performance in satellite-terrestrial network.

Lauri Sormunen, Henrik Martikainen, Jani Puttonen, Dorin Panaitopol, “Co-Existence of Terrestrial and Non-Terrestrial Networks on Adjacent Frequency Bands“, The 11th Advanced Satellite Multimedia Conference and the 17th Signal Processing for Space Communications Workshop (ASMS/SPSC), 6–8 September 2022.

This paper presents the latest achievements with respect to 3GPP Release-17 adjacent band coexistence simulation work on 5G New Radio Non-Terrestrial Networks (NTNs) for satellite communications. For the first time, 3GPP considered the introduction of Mobile Satellite Service (MSS) frequency bands for 3GPP User Equipment (UE) direct connectivity with satellites and had to consider the coexistence in adjacent bands with Terrestrial Networks (TNs).

This paper will further explain the most challenging and the main surprising outcomes of this work, which opened new market opportunities for both terrestrial and non-terrestrial stakeholders.

The main conclusions can be summarized as (1) NTN UE can reuse the current requirements of the TN UE, (2) the satellite connectivity does not require a dedicated satellite waveform, and (3) TN can co-exist with NTN on adjacent channels with relaxed ACIR requirements for the tested simulation scenario.

Jani Puttonen, Alessandro Guidotti, Alessandro Vanelli-Coralli, Vincenzo Schena, Nicolas Chuberre, Mohamed El Jaafari, Stefano Cioni, “The Path to 5G-Advanced and 6G Non-Terrestrial Network Systems“, The 11th Advanced Satellite Multimedia Conference and the 17th Signal Processing for Space Communications Workshop (ASMS/SPSC), 6–8 September 2022.

Today, 5G networks are being worldwide rolled out, with significant benefits in our economy and society. However, 5G systems alone are not expected to be sufficient for the challenges that 2030 networks will experience, including, e.g., always-on networks, 1 Tbps peak data rate, <10 cm positioning, etc. Thus, the definition of evolutions of the 5G systems and their (r)evolutions are already being addressed by the scientific and industrial communities, targeting 5G-Advanced (5G-A) and 6G. In this framework, Non-Terrestrial Networks (NTN) have successfully been integrated in 3GPP Rel. 17 and it is expected that they will play an even more pivotal role for 5G-A (up to Rel. 20) and 6G systems (beyond Rel. 20). In this paper, we explore the path that will lead to 5G-A and 6G NTN communications, providing a clear perspective in terms of system architecture, services, technologies, and standardisation roadmap.

Timo Nihtilä, Heikki Berg, “Energy Consumption of DECT-2020 NR Mesh Network“, EuCNC & 6G Summit, 7-9 June, 2022.

ETSI DECT-2020 New Radio (NR) is a new flexible radio interface targeted to support a broad range of wireless Internet of Things (IoT) applications. Recent reports have shown that DECT-2020 NR achieves good delay performance and it has been shown to fulfill both massive machine-type communications (mMTC) and ultra-reliable low latency communications (URLLC) requirements for 5th generation (5G) networks.

A unique aspect of DECT-2020 as a 5G technology is that it is an autonomous wireless mesh network (WMN) protocol where the devices construct and uphold the network independently without the need for base stations or core network architecture. Instead, DECT-2020 NR relies on part of the network devices taking the role of a router to relay data through the network. This makes deployment of a DECT-2020 NR network affordable and extremely easy, but due to the nature of the medium access protocol, the routing responsibility adds an additional energy consumption burden to the nodes, who in the IoT domain are likely to be equipped with a limited battery capacity.

In this paper, we analyze by system level simulations the energy consumption of DECT-2020 NR networks with different network sizes and topologies and how the reported low latencies can be upheld given the energy constraints of IoT devices.