Krzysztof Malon

• Military University of Technology

Apart from efficient use of assigned spectral resources as a primary user, Cognitive Radio (CR) has the ability to act as a secondary user, utilizing available radio resources, which are not used by primary users for a certain period of time. This paper refers to mobile CR network management, based on multi-stage machine method. The article shows t...

Cognitive Radio (CR) usually performs an analysis of the existing environment, enabling collection of all information on current spectrum use and available resources, to decide on its own transmission parameters to optimize communication performance. From practical point of view, the principal task of spectrum sensing is an efficient detection of d...

Fourth-generation (4G) mobile networks are successively replaced by fifth-generation (5G) ones, based on the new releases of the 3rd Generation Partnership Project (3GPP) standard. 5G generation is dedicated to civilian users and the conducted analytical work shows that it has numerous technological gaps that prevent its direct implementation in mi...

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 environme...

Fifth-generation (5G) technology is currently developing in mobile networks. The civilian 3rd Generation Partnership Project (3GPP) standard is the basis for this implementation. Higher throughput, network capacity, user density, and lower latency are the main advantages offered by 5G over Long Term Evolution (LTE) and older standards. For this rea...

This 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...

Modern wireless communication systems use various technological solutions to increase the efficiency of created radio networks. This efficiency also applies to radio resources. Currently, the utilization of a radio environment map (REM) is one of the directions allowing to improve radio resource management. The REM is increasingly used in emerging...

This paper presents a solution for building awareness of the electromagnetic situation in cognitive mobile ad hoc networks (MANET) using the cooperative spectrum sensing method. Signal detection is performed using energy detectors with noise level estimation. Based on the evidence theory, the fusion center decides on the particular channel occupanc...

This paper presents an algorithm that supports the dynamic spectrum access process in cognitive radio networks by generating a sorted list of best radio channels or by identifying those frequency ranges that are not in use temporarily. The concept is based on the reinforcement learning technique named Q-learning. To evaluate the utility of individu...

Wireless sensor networks are an increasingly popular tool for monitoring various environmental parameters. They can also be used for monitoring the electromagnetic spectrum. Wireless sensors, due to their small size, typically have simplified radio receivers with reduced sensitivity and use small antennas. As a result, their effective performance a...

Efficient access to the spectral resources becomes a challenge for future military wireless communication systems. It requires spectral situation awareness, knowledge of current regulations, local policies and hardware platform limitations. It can be achieved by cognitive radios, realizing cognitive cycle, consisting typically of continuous observa...

Ocena skuteczności zakłóceń odzewowych w sieciach mobilnych Streszczenie. Artykuł dotyczy tematyki związanej z efektywnością zakłóceń celowych i odpornością na nie sieci radiowych. W pracy przedstawiono problematykę zakłócania łączności oraz stanowisko laboratoryjne umożliwiające badania skuteczności zakłóceń odzewowych. Na przykładzie systemu radi...

W artykule przedstawiono ideę rozproszonego zarządzania mobilną siecią radiową bazującą na technologii radia kognitywnego. Została ona zaimplementowana w programowym symulatorze CORASMA, zrealizowanym na bazie pakietu OMNet++. Stworzone narzędzie pozwala badać efektywność opracowanych rozwiązań kognitywnych w rozległych sieciach ad hoc, które chara...

Monitorowanie widma (sensing) jest podstawowym narzędziem, które zapewnia faktyczną możliwość tworzenia nowoczesnych sieci w technologii radia kognitywnego. Sensing pozwala śledzić na bieżąco sytuację elek-tromagnetyczną, dzięki czemu można lepiej wykorzystać dostępne zasoby radiowe oraz dostosować działanie sieci do zmiennych warunków środowiskowy...

Cognitive radio networks are promising systems to enable efficient use of spectral resources, thanks to identification of Primary Users (PU) possessing guaranteed radio resources and Secondary Users (SU), trying to use temporary unused channels. Assuming that PU traffic is low, it can switch off specific subcarriers in OFDM signal and this subbands...

This paper presents methods of spectral shaping of OFDM signals to enable spectrum sharing with other transmissions. Proposed methods are based on carrier suppression algorithms, using both windowing technique and adaptation of modulating schemes on specific subcarriers. Moreover compatibility of OFDM signals generated by asynchronous transmitters,...