EEC-GA: energy-efficient clustering approach using genetic algorithm for heterogeneous wireless sensor networks. - In: The 36th International Conference on Information Networking (ICOIN 2022), (2022), S. 280-286
In a wireless sensor network (WSN), sensor nodes are distributed in a predefined environment, collecting environmental data and transferring them to the base station or sink for processing and analysis. In the meantime, much research has been done on heterogeneous wireless sensor networks. Due to the fact that in a heterogeneous wireless sensor network (HWSN) factors such as primary energy, data processing ability, etc. greatly affect the life of the network, the selection of cluster heads (CHs) for coordinating a cluster of sensor nodes has created a wide range for further development of network efficiency capabilities. In this work, an event-driven energy-efficient protocol based on a genetic algorithm is proposed that uses various parameters such as the remaining energy of the node, the minimum distance of a node to the base station, and also the degree of the neighborhood of a node as fitness function values, and evaluates solutions in a heterogeneous wireless sensor network. For evaluating the proposal, network stability, energy consumption, death of the first node, and number of living nodes per round are considered as evaluation criteria.
https://doi.org/10.1109/ICOIN53446.2022.9687275
Investigations on non-linear effects in power amplifiers for THz channel sounding applications. - Ilmenau. - 97 Seiten
Technische Universität Ilmenau, Masterarbeit 2022
Die Entwicklung der drahtlosen Kommunikation hat nicht nur verschiedene Generationen der Mobilkommunikation auf hohe Bandbreiten ausgerichtet, sondern auch auf den Einsatz von Ultrabreitband. THz- und mm-Wellen-Frequenzbereiche wurden als der Modus Operandi für die Kommunikation in den kommenden Generationen der drahtlosen und mobilen Kommunikation skizziert. Die Verfügbarkeit von Frequenzen in diesen Bereichen bietet nicht nur die Möglichkeit höherer Datenraten, sondern auch ein Layout für die futuristische Kommunikation, an der derzeit geforscht wird und die über die fünfte Generation (5G) und die zukünftige sechste Generation (6G) hinausgeht. Da die unteren THz-Subbänder eine angemessene Datenrate bieten sollen, die den Anforderungen der 6G-Generation entspricht, sind die Charakterisierung und Personifizierung der verschiedenen Aspekte der Frequenzen in diesen Spektralbereichen von größter Bedeutung. Die Nutzung solcher Frequenzbänder hat ihre Nachteile, da höhere Frequenzen nur für die Übertragung über kurze Entfernungen geeignet sind und für die Kommunikation über größere Entfernungen eine höhere Sendeleistung erforderlich ist. Eine Erhöhung der Sendeleistung ist nicht immer sinnvoll, weil sie zu Nachbarkanalstörungen bei benachbarten Kommunikationen führt. Um dieses Problem zu überwinden, wird ein Leistungsverstärker verwendet, um das Signal vor der Übertragung zu verstärken. Die Verstärkung führt jedoch auch zu einigen nichtlinearen Effekten, die zu nichtlinearen Verzerrungen führen, die die Kommunikation in Form von Spektralwachstum, In-Band- und Außer-Band-Verzerrungen beeinträchtigen und zu einer niedrigeren Bitfehlerrate führen. Die Schwere der Schwankungen im Mittelwert und in der Spitze des Signals ist einer der Hauptgründe für diese nichtlinearen Auswirkungen. In dieser Arbeit wurden zunächst sowohl die Faktoren als auch die daraus resultierenden nichtlinearen Auswirkungen zuerst untersucht. Anschließend werden die Modellierungsansätze und Reduktionstechniken diskutiert. Um die Nichtlinearitäten zu messen und zu charakterisieren, ist ein geeignetes Anregungssignal erforderlich. Es werden verschiedene Faktoren eines angemessenen Signals diskutiert, und aus dem Vergleich verschiedener Signaltypen wird auf der Grundlage dieser Metriken das Newman-Multisine-Signal ausgewählt. Ein Messsystem, das einen Arbiträrwellengenerator, ein digitales Phosphoroszilloskop und einen Leistungsverstärker umfasst, ist implementiert. Darüber hinaus wird MATLAB zur Bestimmug und Analyse verschiedener nichtlinearer Aspekte verwendet. Die durch nichtlineare Effekte hervorgerufene Außerband-Verzerrung wird als Vielfaches der Größenordnung der Verzerrung und der höchsten Frequenzkomponente des Signals gemessen; darüber hinaus wird auch ein direkter Zusammenhang zwischen der Inband-Verzerrung und der Frequenz und dem Leistungsverstärker gemessen. Um die Signalschwankungen zu reduzieren, wurden mehrere Abschwächungstechniken implementiert, deren Effizienz gemessen und verglichen wird. Die Ergebnisse zeigen, dass die Verringerung der Signalschwankungen im Breitbandbereich zu einer besseren Systemleistung führt und zur Verbesserung der Stabilität des Gesamtsystems beiträgt, indem der lineare Betrieb des Leistungsverstärkers erhöht wird.
Radar scheme with raised reflector for NLOS vehicle detection. - In: IEEE transactions on intelligent transportation systems, Bd. 23 (2022), 7, S. 9037-9045
The employment of passive reflectors enables the millimeter-wave automotive radars to detect an approaching vehicle in non-line-of-sight conditions. In this paper, the installation of such reflectors above the sidewalk at an intersection is proposed and studied, avoiding pedestrians' blockage and road dust effect at ground level. Through the analysis of the backscattering power, it is shown that the suggested scheme may detect an approaching vehicle in the blind zone at distances of 30,łdots,50 m to the intersection point. Additionally, the analysis shows that efficient operation is highly dependent on the spatial orientation and size of the reflector. Even a few degrees rotation may change the detecting range by several meters. In turn, the larger area of the reflector may cover longer detecting distances, improving the radar scheme's overall performance. It is also shown that further performance enhancement can be achieved by employing a C-type radar, contributing an extra 5 dB to the backscattering power relative to an A-type radar. However, despite these improvements, the strongest scattering centre of the detectable vehicle is systematically identified to the bumper zone.
https://doi.org/10.1109/TITS.2021.3090313
A comprehensive survey on cooperative intersection management for heterogeneous connected vehicles. - In: IEEE access, ISSN 2169-3536, Bd. 10 (2022), S. 7937-7972
https://doi.org/10.1109/ACCESS.2022.3142450
Kronecker product-based space-time block codes. - In: IEEE wireless communications letters, ISSN 2162-2345, Bd. 11 (2022), 2, S. 386-390
This letter presents a new approach to construct space-time block codes (STBCs) based on the Kronecker product. The proposed Kronecker-structured STBCs (K-STBCs) are specially designed for constant modulus constellations and include the classical linear dispersion (LD) codes as a special case. Its inherent Kronecker structure offers additional coding gains due to the mutual spreading of multiple space-time codewords. At the receiver, an efficient algorithm is derived by recasting the decoding of the K-STBCs as a rank-one tensor approximation problem. The proposed decoding algorithm provides a good bit error ratio (BER) performance especially, in the low signal-to-noise ratio (SNR) regime. In particular, our numerical results show that K-STBCs outperform the existing quasi-orthogonal STBCs due to the denoising gain offered by the proposed rank-one approximation based detector.
https://doi.org/10.1109/LWC.2021.3129460
Make some noise: energy-efficient 38 Gbit/s wide-range fully-configurable linear feedback shift register. - In: SMACD / PRIME 2021, (2021), S. 384-387
https://ieeexplore.ieee.org/document/9547997
Every clock counts - 41 GHz wide-range integer-N clock divider. - In: SMACD / PRIME 2021, (2021), S. 388-391
https://ieeexplore.ieee.org/document/9547998
Towards applying IPSec between edge switches and end users to counter DDoS attacks in SDNs. - In: 2021 IEEE 23rd International Conference on High Performance Computing Communications/7th International Conference on Data Science Systems/19th International Conference on Smart City/7th International Conference on Dependability in Sensor, Cloud Big Data Systems Applications, (2021), S. 1545-1551
Software-Defined Networking (SDN) is a new networking paradigm with many advantages compared to traditional networks, such as reliability, scalability, and flexibility. However, SDN inherits some vulnerabilities from traditional networks and even shows new properties that malicious users might exploit as vulnerable aspects. In this paper, a novel solution is introduced based on the notion of the IP Security protocol (IPSec) and an adaptive threshold algorithm to counter Distributed Denial of Service (DDoS) attacks and freeloading attacks. The simulation results show the ability of the proposed countermeasure to prevent these attacks by distinguishing between benign and malicious users, which shows a notable enhancement compared to previous approaches.
https://doi.org/10.1109/HPCC-DSS-SmartCity-DependSys53884.2021.00229
V2X in 3GPP standardization: NR sidelink in Release-16 and beyond. - In: IEEE communications standards magazine, ISSN 2471-2833, Bd. 5 (2021), 1, S. 12-21
The 5G mobile network brings several new features that can be applied to existing and new applications. High reliability, low latency, and high data rate are some of the features that fulfill the requirements of vehicular networks. Vehicular networks aim to provide safety for road users and several additional advantages such as enhanced traffic efficiency and in-vehicle infotainment services. This article summarizes the most important aspects of NR-V2X, which is standardized by 3GPP, focusing on sidelink communication. The main part of this work belongs to 3GPP Release 16, which is the first 3GPP release for NR-V2X, and the work/study items of the future Release 17.
https://doi.org/10.1109/MCOMSTD.001.2000070
Coupled CP decomposition of EEG and MEG magnetometer and gradiometer measurements via the coupled SECSI framework. - In: Conference record of the Fifty-Fifth Asilomar Conference on Signals, Systems & Computers, (2021), S. 1661-1667
Recent research has shown that the joint processing of simultaneously recorded EEG-MEG signals can be beneficial compared to the separate analysis of data if the corresponding tensors have one of their factor matrices in common. In this study, we perform a joint CP decomposition of simultaneously recorded EEG and MEG magnetometer as well as gradiometer measurements via a new extension of the coupled SEmi-Algebraic framework for the approximate CP decomposition via SImultaneous matrix diagonalization (SECSI) to jointly factorize several tensors with at least one factor matrix in common. In case of the biomedical data, the four measured tensors have the factor matrix in the frequency domain in common. The developed coupled SECSI algorithm allows extracting the signal sources even in ill-conditioned scenarios. In the final processing step, coupled SECSI chooses the best out of a variety of possible factor matrix estimates, i.e., a combination that leads to the smallest value of the reconstruction error. However, for data tensors that do not exhibit significant coupling, the uncoupled solution can also be selected. The results are evaluated on measured as well as on synthetic data and compared with other state-of-the-art approaches.
https://doi.org/10.1109/IEEECONF53345.2021.9723118