Spectrum Awareness in Cognitive Radio Systems

The paper addresses the issue of the Electromagnetic Environment Situational Awareness techniques. The main focus is put on sensing and the Radio Environment Map. These two dynamic techniques are described in detail. The Radio Environment Map is considered the essential part of the spectrum management system. It is described how the density and deployment of sensors affect the quality of maps and it is analysed which methods are the most suitable for map construction. Additionally, the paper characterizes several sensing methods

Spectrum Awareness in Cognitive Radio Systems

The paper addresses the issue of the Electromagnetic Environment Situational Awareness techniques. The main focus is put on sensing and the Radio Environment Map. These two dynamic techniques are described in detail. The Radio Environment Map is considered the essential part of the spectrum management system. It is described how the density and deployment of sensors affect the quality of maps and it is analysed which methods are the most suitable for map construction. Additionally, the paper characterizes several sensing methods

Surface passivation of (100) GaSb using self-assembled monolayers of long-chain octadecanethiol

The passivation of (100) GaSb surface was investigated by means of the long-chain octadecanethiol (ODT) self-assembled monolayer (SAM). The properties of ODT SAM on (100) GaSb were characterized by the atomic force microscopy using Kelvin probe force microscopy mode and X-ray photoelectron spectroscopy. The chemical treatment of 10mM ODT-C2H5OH has been applied to the passivation of a type-II superlattice InAs/GaSb photodetector. The electrical measurements indicate that the current density was reduced by one order of magnitude as compared to an unpassivated photodetector

Spectrum Awareness for Cognitive Radios Supported by Radio Environment Maps: Zonal Approach

In this paper, we present the concept of the Radio Environment Map (REM) designed to ensure electromagnetic situational awareness of cognitive radio networks. The map construction techniques based on spatial statistics are presented. The results of field tests done for Ultra High Frequency (UHF) range with different numbers of sensors are shown. Exemplary maps with selected interpolation techniques are presented. Control points where the signal from licensed users is correctly estimated are identified. Finally, the map quality is assessed, and the most promising interpolation techniques are selected

Electromagnetic Environment Situational Awareness

Military radio, EW and RF sensor systems operate in a congested and contested electromagnetic environment. The NATO Science and Technology Organization established the Research Task Group 069 in order to take charge of the IST-146 project on Electromagnetic Environment Situational Awareness. The project was aimed at evaluating the operational benefits for NATO in line with the Electromagnetic Spectrum Strategy and at evaluating the Radio Environmental Map (REM) technology. The paper describes the military scenario considered for the study. Its operational analysis establishes the importance of Electromagnetic Spectrum Command and Control integrated with other C2 processes. The description of the data sources, models, and representation is done. Key user benefits are highlighted. Then proposals for possible evolution of electromagnetic operations and spectrum management within NATO are made. The paper further describes the proposed reference architecture based on the Internet of Things (IoT). It establishes how the relationships between the REM elements have been validated through the project scenario. Tests and simulations, carried out for the construction of measurement-based REMs and transmitter localization, are presented. The paper finally describes the proposed demonstration, which enables understanding through visualization of an interference situation and de-confliction by dynamically re-assigning frequencies

Heterogeneous Wireless Sensor Networks Enabled Situational Awareness Enhancement for Armed Forces Operating in an Urban Environment

Situational awareness of armed forces acting in an urban environment is a key factor determining the success of military operations. In 2021 the European Defence Agency established the project on Wireless Sensor Networks for Urban Local Areas Surveillance. The main goal of the project is to assess how the situational awareness in an urban environment can be enhanced with the application of heterogeneous, autonomous and reconfigurable sensors. The paper presents a novel comprehensive approach that takes into account modelling and management of heterogeneous sensors, energy harvesting techniques, planning and management of the communication backbone, network security for data transfer and authorization for secure information exchange. The architecture of the system and the information flow are presented. The topology aspects are discussed and the sensing part is described. The paper finally highlights new essential enhancements of C2 with particular emphasis on mission planning, data fusion and threat prediction.Green Open Access added to TU Delft Institutional Repository 'You share, we take care!' - Taverne project https://www.openaccess.nl/en/you-share-we-take-care Otherwise as indicated in the copyright section: the publisher is the copyright holder of this work and the author uses the Dutch legislation to make this work public.Networked System