Search
Filters
total: 167
filtered: 159
Search results for: UMTS/UMTS-LTE
-
Practical Approach to IP Scheduled Throughput Measurements in Dual Connectivity Systems
PublicationIP scheduled throughput defined according to 3GPP TS 36.314 reflects user throughput regardless of traffic characteristics, and therefore has become one of the most important indicators for monitoring Quality of Service (QoS) of the end user in Evolved Universal Terrestrial Radio Access Network (E-UTRAN). However, networks built on a distributed architecture make the above definition impossible to be applied directly due to the...
-
A simplified channel estimation procedure for NB-IoT downlink
PublicationThis paper presents a low-complexity channel estimation procedure which is suitable for use in energy-efficient NB-IoT user equipment devices. The procedure is based on the well-established least squares scheme, followed by linear interpolation in the time domain and averaging in the frequency domain. The quality of channel estimation vs. signal-to-noise ratio is evaluated for two channel models and compared with the performance...
-
Jamming and jamming mitigation for selected 5G military scenarios
PublicationThis paper presents jamming and jamming mitigation techniques, which can be used in relation to emerging military systems based on fifth-generation (5G) technology. Nowadays, 5G technology provides incremental improvements over Long Term Evolution (LTE) networks resulting in the enhancement of civilian communications. Considering enormous possible applications of this new technology, it is feasible to use them in military utilities....
-
Path Loss Analysis for the IoT Applications in the Urban and Indoor Environments
PublicationThe Internet of Things (IoT) networks concept implies their presence in a various and untypical locations, usually with a disturbed radio signals propagation. In the presented paper an investigation of an additional path loss observed in an underground environment was described. The proposed measurement locations correspond to the operation areas of rapidly growing narrowband IoT (NBIoT) networks, the ones using the Long Term Evolution...
-
Systemy radiokomunikacyjne w zastosowaniach specjalnych - ocena przydatności i przegląd rozwiązań
PublicationW pracy opisano wybrane wyniki analizy i prac badawczych prowadzonych w Katedrze Systemów i Sieci Radiokomunikacyjnych Politechniki Gdańskiej. W tym też kontekście opisano m.in. zastosowania i charakterystyki wybranych systemów radiokomunikacyjnych, istotnych z punktu widzenia służb bezpieczeństwa publicznego, takich jak np.: TETRA, TEDS, LTE oraz cdma2000. W ramach artykułu omówiono także zagadnienia związane z rozwojem techniki...
-
Definiowany programowo uniwersalny interfejs radiowy inteligentnych urządzeń internetu rzeczy
PublicationIntensywny wzrost liczby urządzeń komunikujących się ze sobą na dużym obszarze wymaga opracowywania i realizacji rozwiązań systemowych. Z tego względu organizacja 3GPP zdefiniowała wąskopasmowy interfejs radiowy NB-IoT (Narrowband Internet of Things) będący podsystemem LTE (Long Term Evolution) na potrzeby zastosowań IoT niewymagających dużych przepływności. W niniejszym artykule przedstawiono charakterystykę systemu NB-IoT, a...
-
Study on transmission quality in cellular 4G and 5G networks between 2019–2021: Impact of the COVID-19 pandemic on the level of provided services by operating base transceiver stations
PublicationThe COVID-19 pandemic has significantly limited user mobility, not least among students. Remote learning had a particular impact on resource allocation in relation to using terrestrial cellular networks, especially 4G systems in urban agglomerations. This paper presents the results of a quality evaluation of an outdoor environment, carried out between 2019 and 2021 on the campus of a technical university. Annual studies are conducted...
-
A Simplistic Downlink Channel Estimation Method for NB-IoT
PublicationThis paper presents a downlink channel estimation method intended for a Narrowband Internet of Things (NB-IoT) access link. Due to its low computational complexity, this method is well suited for energy-efficient IoT devices, still providing acceptable reception quality in terms of signal-to-noise (SNR) performance. This paper describes the physical layer of NB-IoT within the scope of channel estimation, and also reviews existing...
-
DATABASE AND BIGDATA PROCESSING SYSTEM FOR ANALYSIS OF AIS MESSAGES IN THE NETBALTIC RESEARCH PROJECT
PublicationA specialized database and a software tool for graphical and numerical presentation of maritime measurement results has been designed and implemented as part of the research conducted under the netBaltic project (Internet over the Baltic Sea – the implementation of a multi-system, self-organizing broadband communications network over the sea for enhancing navigation safety through the development of e-navigation services.) The...