Abstract
Research into software defined radio technologies reaches a level [MITO 00], where developments in hardware technology [AJLU 01] and the existing multiband-multimode terminals are moving closer to the ideal 'Software Radio' [MITO 00]. Even the long neglected aspect of the reconfiguration of the higher layers of the protocol stack found entry into the current research efforts, see [SIEB 00] and [MOES Ola]. In addition, the reconfiguration techniques used in the higher layers are also used for the implementation of the lower (physical, etc) layers [HENK 03]. The reconfiguration of the software radio is a rather complex task, numerous parameters may influence the reconfiguration procedures and the low level programmability opens the possibility for any, even un-wanted configurations. Ensuring a standard compliance and a correct functioning of the reconfigurable systems will be the biggest challenge in the commercial Software Radio deployment. The work investigates reconfigurability issues of reconfigurable nodes (terminals, base stations, access points, etc.), the interactions within the future reconfigurable communication systems (terminals and networks) and provides an approach (so called reconfiguration plane) that can be used to ensure the functionality and integrity of radio systems before, during and after reconfiguration. It provides a complete design and implementation of the reconfiguration plane or common reconfiguration middleware, the distinctive interfaces and the communication between the different blocks of the plane. These encapsulate the configurable hardware platform, the reconfiguration management, control and data to the radio configuration interfaces i.e. 'radio-application software', the messages' exchange between network and mobile nodes, and presents a mechanism for secure download of reconfiguration software. The work identifies some of the regulatory limitations, but moreover it captures and describes the complexity that has to be considered when radio equipment can be flexibly configured and reconfigured through alterations to the hardware/software combinations. It facilitates the use of third party configuration software by providing mechanisms, which ensure the conformance to regulated radio standards satisfying the user, operator, software, and network providers' requirements. This also includes 'standard test suites' to certify that the instantiation of the configuration implements both the waveform and higher layers correctly [GUDA 00]. It addresses the issues of the verification and the validation of reconfigurable systems and configurations using the Specification and Description Language (SDL) implementation of the reconfiguration plane. As a part of the thesis is the evaluation of the 'cost of reconfiguration' which provides bases of estimation of the minimum design and implementation of software radio management architectures. This developed method is used to evaluate reconfiguration plane and to provide results for the cost of the reconfiguration scenarios applied at design time. This work concludes with a brief summary and conclusions, and an overview of the research that could be undertaken as future work.