arXiv subjects

Juho Pirskanen

Publications and source records attributed to Juho Pirskanen.

5 recordsLinked to original sources

arXiv2026

Topology Construction Algorithms for DECT NR+ in Normal and Ultra-Dense Deployments

The 5G-grade DECT NR+ technology designed to support massive machine-type communications (mMTC) relies on the decentralized mesh connectivity concept. The currently utilized topology construction algorithms are very sensitive to the node density, which causes interference at the node association phase and may lead to instable topologies. In this study, we propose several algorithms that need to be utilized at relay and leaf nodes to allow stabilization of the topology: (i) load-dependent relay allocation, (ii) hysteresis-based association control, (iii) blacklist-based association control, and (iv) smart beacon placement. Due to the complex interference structure in DECT NR+ mesh systems, we utilize system-level simulations to assess the performance in both normal and ultra-dense conditions in terms of the efficiency of topology construction and the performance characteristics of the resulting topology. Our results show that dense DECT NR+ networks do suffer from topology instability, with reassociation rates exceeding 10 per second and recovery times lasting over 10 minutes. By implementing the proposed mechanisms, the network dynamically scales, reducing the number of required relays by more than half, from 34% to 15%. They also stabilize the topology by reducing the reassociation rates to just 2-3 per second allowing large-scale networks of several hundred nodes to operate efficiently.

cs.NI↗

arXiv2025

DECT-2020 NR Link Distance Performance in Varying Environments: Models and Measurements

Digital Enhanced Cordless Telecommunications 2020 New Radio (DECT-2020 NR) has garnered recognition as an alternative for cellular 5G technology in the internet of things industry. This paper presents a study centered around the analysis of the link distance performance in varying environments for DECT-2020 NR. The study extensively examines and analyzes received signal strength indicator and resulting path loss values in comparison with theoretical models, as well as packet success rates (SR) and signal-to-noise ratio against varying distances. The measurements show that with an SR of over 90%, an antenna height of 1.5 m, indoor link distances with a single device-to-device connection with 0 dBm transmission (TX) power can reach over 60 m in non-line-of-sight (NLOS) areas and up to 190 m in LOS areas with smaller -8 dBm TX power. Similarly, for outdoor use cases, link distances of over 600 m can be reached with +19 dBm TX power.

cs.NI↗

arXiv2022

DECT-2020 New Radio: The Next Step Towards 5G Massive Machine-Type Communications

Massive machine type communications (mMTC) is one of the cornerstone services that have to be supported by 5G systems. 3GPP has already introduced LTE-M and NB-IoT, often referred to as cellular IoT, in 3GPP Releases 13, 14, and 15 and submitted these technologies as part of 3GPP IMT-2020 (i.e., 5G) technology submission to ITU-R. Even though NB-IoT and LTE-M have shown to satisfy 5G mMTC requirements defined by ITU-R, it is expected that these cellular IoT solutions will not address all aspects of IoT and ongoing digitalization, including the support for direct communication between "things" with flexible deployments, different business models, as well as support for even higher node densities and enhanced coverage. In this paper, we introduce the DECT-2020 standard recently published by ETSI for mMTC communications. We evaluate its performance and compare it to the existing LPWAN solutions showing that it outperforms those in terms of supported density of nodes while still keeping delay and loss guarantees at the required level.

cs.NI↗

arXiv2018

Transparent Tx and Rx Waveform Processing for 5G New Radio Mobile Communications

Several different waveform processing techniques have been studied and proposed for the 5G new radio (NR) physical layer, to support new mixed numerology and asynchronous services. The evaluation and comparison of these different techniques is commonly based on matched waveform processing in the transmitter and receiver units. In this article, it is shown that different techniques can be flexibly mixed, allowing to separately optimize complexity-performance trade-offs for transmitter and receiver implementations. Mixing of different waveform processing techniques is possible by setting adequate requirements for transmitter and receiver baseband processing allowing transparent design. The basic framework of how transmitter and receiver units can be independently applied and evaluated in the context of transparent design and an extensive set of examples of the achievable radio link performance with unmatched transmitter and receiver waveform processing are provided. The discussed approach and solutions simplify standardization, improve transparent transmitter and receiver coexistence, and allow future-proof evolution path for performance improvements in 5G NR physical layer hardware and algorithm design.

eess.SP↗

arXiv2017

Efficient Fast-Convolution-Based Waveform Processing for 5G Physical Layer

This paper investigates the application of fast-convolution (FC) filtering schemes for flexible and effective waveform generation and processing in the fifth generation (5G) systems. FC-based filtering is presented as a generic multimode waveform processing engine while, following the progress of 5G new radio standardization in the Third-Generation Partnership Project, the main focus is on efficient generation and processing of subband-filtered cyclic prefix orthogonal frequency-division multiplexing (CP-OFDM) signals. First, a matrix model for analyzing FC filter processing responses is presented and used for designing optimized multiplexing of filtered groups of CP-OFDM physical resource blocks (PRBs) in a spectrally well-localized manner, i.e., with narrow guardbands. Subband filtering is able to suppress interference leakage between adjacent subbands, thus supporting independent waveform parametrization and different numerologies for different groups of PRBs, as well as asynchronous multiuser operation in uplink. These are central ingredients in the 5G waveform developments, particularly at sub-6-GHz bands. The FC filter optimization criterion is passband error vector magnitude minimization subject to a given subband band-limitation constraint. Optimized designs with different guardband widths, PRB group sizes, and essential design parameters are compared in terms of interference levels and implementation complexity. Finally, extensive coded 5G radio link simulation results are presented to compare the proposed approach with other subband-filtered CP-OFDM schemes and time-domain windowing methods, considering cases with different numerologies or asynchronous transmissions in adjacent subbands. Also the feasibility of using independent transmitter and receiver processing for CP-OFDM spectrum control is demonstrated.

cs.IT↗