Kostas Tsagkaris

Interference level configuration in CDMA-based cellular networks

The accommodation of various traffic load situations in W-CDMA-based cellular systems requires the engineering of the allowed interference levels per cell. This paper presents functionality that can complement the design and management as well as the mechanisms required. The overall scheme is called Interference Level Configuration (ILC). It relies on the solution of problems, which will be concisely defined, optimally formulated and solved by computationally efficient algorithms. The proposed herewith algorithms are also able to co-operate with soft computing (SC) methods to the solution of problems in the power control domain. Numerical results will be presented.

Location- and Service-Aware Downlink Transmission Power Allocation in WCDMA-Based Cellular Networks

Power constitutes an essential controllable resource for the improvement of the radio link performance in Wideband Code Division Multiple Access (WCDMA)-based cellular networks. In addition, complementary to traditional services, location-based services (LBS) have emerged as a growing area for mobile service providers bringing in the foreground the potential for a location-aware resource management. To this effect, this paper addresses a location- and service-aware downlink transmission power allocation problem (DTPA), the solution of which is suitable for the management or control domain of multi-service, WCDMA-based cellular networks. Given a specific traffic load situation that includes location and required service information, the solution of the DTPA problem aims at finding the optimum feasible allocation of power to the set of downlink connections that should be supported by the system. The problem is concisely defined, mathematically formulated and solved by a computationally efficient algorithm. Simulation and numerical results are presented.

Management of the power control operation in HIPERLAN/2 networks

BRAN/WLAN systems, e.g., HIPERLAN/2, IEEE 802.11a, etc., are seen as a promising solution for covering residential, business, transport, tourism, etc., environments, and generally areas of high demand, characterized as “hot spots”. This paper presents management functionality for augmenting the potential exploitation of one of these systems, HIPERLAN/2, by making feasible their (loose or tight) integration in a composite radio (CR) context. The approach will be the following. The first point will be to revisit the main features of a HIPERLAN/2 system. Next, the architecture of a general Service and Network Management System (SNMS), which has been developed for assisting wireless systems in their operation in a CR context, will be briefly presented. The next main point will be the presentation of the functionality of the SNMS component that is tailored to the managed HIPERLAN/2 technology and specifically to the configuration of the Power Control (PC) functionality. An algorithm for configuring the PC operation, based on a greedy algorithm and a neural network, will be presented. A relevant resource management problem, which should be efficiently solved for exploiting HIPERLAN/2 networks, will be addressed. Numerical results will be presented.

A Framework to Support Interoperability in IoT and Facilitate the Development and Deployment of Highly Distributed Cloud Applications

The constantly increased variety of available hardware and software solutions for the IoT sector is facilitating the development of novel applications, but at the same time the lack of standardized or widely accepted means of interaction, deployment and configuration is seriously hindering the IoT’s potential. The ARCADIA framework is an application development paradigm that enables the cooperation between software components designed and implemented independently and using various technologies and platforms, so that they can form sophisticated, distributed, cloud applications.