A5073933079- Advanced MIMO Systems Optimization
- Cooperative Communication and Network Coding
- Advanced Wireless Network Optimization
- Advanced Wireless Communication Technologies
- IoT Networks and Protocols
- Wireless Communication Networks Research
- Wireless Body Area Networks
- Power Line Communications and Noise
- Antenna Design and Analysis
- Full-Duplex Wireless Communications
- IoT and Edge/Fog Computing
- Telecommunications and Broadcasting Technologies
- Energy Harvesting in Wireless Networks
- Electromagnetic Compatibility and Measurements
- Millimeter-Wave Propagation and Modeling
- Electromagnetic Fields and Biological Effects
- Advanced Data Processing Techniques
- Irrigation Practices and Water Management
- Satellite Communication Systems
- Microwave and Dielectric Measurement Techniques
- CNS Lymphoma Diagnosis and Treatment
- Lymphoma Diagnosis and Treatment
- IPv6, Mobility, Handover, Networks, Security
- Smart Agriculture and AI
- Food Supply Chain Traceability
University of Piraeus
2012-2022
National Technical University of Athens
2004-2016
National and Kapodistrian University of Athens
2004-2008
Machine-to-machine (M2M) communications over cellular networks pose significant challenges as a result of the large number devices, small data transmissions, and vast applications range. Current solutions based on general packet radio service (GPRS) access proved to be inadequate for supporting M2M ecosystem. Therefore, advanced network releases, such long-term evolution (LTE) LTE-Advanced (LTE-A), should efficiently cater communications. However, increase in signaling overhead diverse...
Agriculture 4.0, as the future of farming technology, includes several key enabling technologies towards sustainable agriculture. The use state-of-the-art technologies, such Internet Things, transform traditional cultivation practices, like irrigation, to modern solutions precision In this paper, we present in detail subsystems and architecture an intelligent irrigation system for agriculture, AREThOU5A IoT platform. We describe operation node that is utilized Moreover, apply radiofrequency...
The extreme traffic load that future wireless networks are expected to accommodate requires a rethinking of the system design. initial estimations indicate that, unlike evolutionary path previous cellular generations was based on spectral efficiency improvements, most substantial amount performance gains will be obtained by means network infrastructure densification. By increasing density operator-deployed elements along with incorporation user-deployed access nodes (ANs) and mobile user...
ABSTRACT Supporting emerging machine‐to‐machine (M2M) communications over Long‐term Evolution (LTE)/LTE Advanced cellular networks in an efficient way will be beneficial for both telecommunication communities. The first step to migrate M2M‐enabled standard is provide these new services through the existing architectures and protocols, while maintaining seamless backward compatibility. To this end, we thoroughly examined a key LTE Medium Access Control entity, which packet scheduler, proposed...
Providing LTE connectivity to emerging Machine-to-Machine (M2M) applications imposes several challenges the operation and optimization of current future 3GPP mobile broadband standard releases. Scheduling in an efficient way M2M traffic over existing MAC infrastructure is decisive for smooth evolution towards M2M-enabled system. The large number connecting devices compared classical terminals, their vastly diverse quality-of-service requirements, call design new packet scheduling schemes...
Ultra network densification is considered a major trend in the evolution of cellular networks, due to its ability bring closer user side and reuse resources maximum extent. In this paper we explore spatial coordination as key empowering technology for next generation (5G) ultra-dense networks. We propose an optimization framework flexibly associating system users with access nodes densely deployed network, opting exploitation control overhead signaling. Combined precoding strategies,...
One of the most significant fifth-generation (5G) technology enablers will be device-to-device (D2D) communication, which refers to capability direct communication between two or more devices without intervention a base station and constitutes promising way improve spectral, energy, latency performance, exploiting physical proximity communicating increasing resource utilization. Furthermore, network infrastructure densification has been considered one substantial methods for system taking...
Water scarcity and desertification are considered to be among the greatest challenges of humanity over coming decades. Worldwide, agriculture accounts 69% total water usage, while industry for 23%, urban use 8%. In Greece, a rural development model poor farming practices have resulted in an overwhelming 83% consumption directed uses. Furthermore, excessive combined with existing pesticides fertilizers usage levels creates exponential problems cycle Greece. Taking into account above...
Ultra network densification and Massive MIMO are considered major 5G enablers since they promise huge capacity gains by exploiting proximity, spectral spatial reuse benefits. Both approaches rely on increasing the number of access elements per user, either through deploying more nodes over an area or antenna node. At network-level, optimal user-association for a densely randomly deployed empowered must account both channel load conditions. In this paper we formulate complex problem, report...
An important enabler towards the successful deployment of any new element/feature to cellular network is investigation and characterization operational conditions where its introduction will enhance performance. Even though there has been significant research activity on potential device-to-device (D2D) communications, are currently no clear indications whether D2D communications actually able provide benefits for a wide range conditions, thus justifying their system. This paper attempts...
Optimizing resource allocation over only the frequency dimension in a single-cell OFDMA network is strictly suboptimal when heterogeneous non-real-time data users coexist. In this work we examine how to jointly exploit multi-user diversity on and time domains towards maximizing cell throughput performance satisfying individual rate fairness QoS constraints.We develop upper bound as well an efficient heuristic algorithm for subcarrier slot which outperforms existing algorithms under...
Network densification along with universal resources reuse is expected to play a key role in the realization of 5G radio access as an enabler for delivering most anticipated network capacity improvements. On one hand, neither additional spectrum allocation nor forthcoming novel air-interface processing techniques will be sufficient sustaining exponentially-increasing mobile data traffic. other enhanced ultra-dense infrastructure deployments are provide remarkable gains, regardless...
An important enabler towards the successful introduction of any new element/feature to cellular network, such as ability allow for direct, device-to-device (D2D) communications, is investigation and characterization operational conditions, e.g., density users, where its deployment will enhance performance. This paper attempts provide a mathematically rigorous set (region) which overlay D2D communications performance in terms average user rate. Using tools from stochastic geometry,...
This paper provides an overview of DECT-2020 NR technology evaluation conducted by the Wireless World Research Forum (WWRF) in context IMT-2020 Evaluation Process solicited International Telecommunication Union (ITU). NR, a Radio Interface Technology developed ETSI TC DECT and Forum, was submitted as candidate along with five other technologies. It is applicable various use cases markets, focus on consumer industrial IoT applications, such industry building automation monitoring. In...
Network densification with universal resources reuse is regarded as a possible solution to increase capacity and deal the "1000x" mobile data challenge in future 3GPP radio access networks. Interference major performance limitation such networks, global coordination of coexisting transmissions comprises technology enabler for achieving high levels. In this work we consider large distributed networks low-cost infrastructure nodes, small-cells or simply points. We explore optimal efficient...
A linear model for evaluating the performance of adaptive resource allocation and user scheduling regarding a single-cell downlink SISO-OFDMA packet data network like LTE is developed in this paper. Based on several power, bit, frequency block frame approaches are examined corresponding upper bounds numerically extracted. We put special emphasis equal power single modulation mode per approaches, since they proposed by 3GPP standardization body. The individual joint effect each system degree...
Adaptive Radio Resource Allocation mechanisms exploiting the inherent frequency selectivity of wireless medium as well multi-user effect are expected to play a key role in emerging next generation OFDMA-based networks. Although plethora studies concerning either constant/guaranteed bit rate (CBR/GBR) or variable rate/best effort (VBR/BE) traffic has been published date, limited amount work devoted mixed OFDMA-centric GBR-BE data problem. In this paper we attempt deal with specific...
A fully automated monitoring system performing measurements of the RF electric field strength in several sites is presented. The consists remote stations and central control unit. are geographically distributed data collection achieved via GSM network. development software tools eliminates any human intervention. measured compared to reference levels defined Greek standards (2000) results presented public on a regular basis using "Hermes" web site (Ref.2). values from significantly below levels.
Advances in cellular networks such as device-to-device communications and full-duplex radios, well the inherent elimination of intra-cell interference achieved by network-controlled multiple access schemes, motivate investigation cross-mode properties under a guard region corresponding to Voronoi cell an point (AP). By modeling positions interfering APs user equipments (UEs) Poisson distributed, analytical expressions for statistics generated either or UEs are obtained based on appropriately...
A novel prototype NB-IoT-based quasi-smart water management platform for irrigation is proposed. The has been deployed in a vineyard Peta village, Greece, as part of the AREThOU5A project. An IoT framework regularly and accurately tracking status soil hydration reporting it to centralized entity further processing since needs are directly related moisture based on specialized hardware that includes low-cost microcontrollers with integrated sensor interfaces telecommunication modems,...
Wireless access through a large distributed network of low-complexity infrastructure nodes empowered with cooperation and coordination capabilities, is an emerging radio architecture, candidate to deal the mobile data capacity crunch. In 3GPP evolutionary path, this known as Cloud-RAN paradigm for future radio. such complex network, MIMO resources optimization paramount importance, in order achieve scaling. paper, we investigate efficient strategies towards optimizing pairing users well...
Abstract Ultra network densification and massive multiple‐input multiple‐output are considered major 5th generation technology enablers, promising huge capacity gains as they offer proximity, spectral spatial reuse benefits. Towards succeeding in harnessing the anticipated gains, a systematic treatment of radio resources management challenges encountered such deployments is utmost importance. In this respect, we introduce study detail user‐association multiple‐access optimisation aspects...
A fully automated, Web controlled, monitoring system, performing measurements of the RF electric field strength in various sites is presented. The system consists several remote measurement stations, installed different area types and a central control unit, which communicates with each station via GSM network. design development focused on end-to-end automation, order to minimize any human intervention during its operation. results as well related information are presented public regular...