Ingo Karla

Multi-radio resource management for communication networks beyond 3G

In ‘Beyond 3G’ wireless networking scenarios, characterized by the cooperation of multiple access networks comprising different radio access technologies, Multi-Radio Resource Management (MRRM) mec ...

Multi-radio resource management for ambient networks

The ambient networks concept targets forthcoming dynamic communication environments, characterized by the presence of a multitude of different wireless devices, radio access technologies, network operators and business actors, which can form instant inter-network agreements with each other. Multi-radio resource management (MRRM) mechanisms, coordinating several radio accesses, fulfill a key role for providing wireless services with improved resource efficiency, coverage and service quality. This paper presents an MRRM concept for Ambient Networks, describes the principal MRRM functions and discusses design criteria

Cost based Heterogeneous Access Management in Multi-Service, Multi-System Scenarios

This paper covers the issue of how mobile users of different service classes should be assigned to a set of radio access technologies (RATs) with overlapping coverage from a practical perspective. The aim is to allocate users with minimum rate constraints to all RATs that the weighted sum of assignable users is maximized. We introduce the concept of resource costs to formulate an optimization problem, which is very expensive to solve (NP-complete). Using the approach of continuous relaxation, we develop a suboptimal radio access selection algorithm which is designed for practical applications and converges close to the optimum. Simulation results show considerable gains of the utility in comparison to a standard Load Balancing Strategy.

Performance of Distributed MXRRM

Recent simulation studies of heterogeneous wireless networks have shown promising system performance improvements by using multi standard radio resource management (MxRRM) with a centralised MxRRM architecture. In the present paper, the distributed MxRRM architecture is studied, including the modelling of signalling, where intersystem cell load information can only be exchanged at certain events. Consequently, the distributed MxRRM entities have to base their decisions on potentially inaccurate load information. The system performance is investigated by simulation studies, where the results of distributed MxRRM scenarios are compared to two reference cases, 1) assuming ideal system information for MxRRM and 2) separated systems without any MxRRM functionality. Furthermore, an additional dedicated mechanism to exchange the load information aiming to improve the load information accuracy is investigated

Infrastructure Cost Benefits of Ambient Networks Multi-Radio Access

Ambient networks multi-radio access technology for efficient multi-operator multi-radio resource management can provide large advantages in terms of improved services to users, new business opportunities, and cost savings. This paper quantifies the potential infrastructure cost savings through a number of techno-economic infrastructure cost comparisons. The results indicate clear potential cost savings with integrated deployment in suburban and urban areas and additional cost savings with multi-operator cooperation when using the ambient networks multi-radio access technology