INSURED project (INtegrated Satellite UMTS Real Environment Demonstrator) D.Dres, G.Pantos, D.Vouyioukas, Prof. P.Constantinou The authors are with National Technical University of Athens Dept. of Electrical Eng., Electroscience Division Abstract : The main objective of the Integrated Satellite UMTS Real Environment Demonstrator (INSURED) project is to demonstrate Satellite-UMTS (S-UMTS) services and functionality in the context of a S-UMTS system demonstrator involving real first generation mobile Low Earth Orbit (LEO) satellites and Personal Communication Systems (PCS). Based on the results obtained from the RACE II Mobile line projects and in particular the strategies, schemes and protocols proposed in RACE II/SAINT, COST and all other ETSI/ITU activities involving mobile satellite applications, the S-UMTS approach towards fully integrated satellite and terrestrial mobile communication will be shown. The project is funded by the European Committee (ACTS) and involves the following partners :  Telespazio (A. Pandolfi, A. Giralda) Aachen University (Dr. Carl-Herbert Rokitansky, Vladimir Obrakovic) Space Engineering (V.Speziale) Siemens Austria (Dr. Hermann Brand, Alexander Vesely) TCC Thomson-CSF (P.Le Bris) CSELT (A.Magliano) Thesa Ltd (N.Balteas, A.Angeletopoulos) NCSR Demokritos (Dr.C.Makropoulos) NTUA (D.Dres, G.Pantos, D.Vouyioukas, Prof. P.Constantinou) I.Introduction The S-UMTS approach towards fully integrated satellite and terrestrial mobile communication will be shown using the RACE SAINT outcomes as a starting point. The integration aspects are deeply investigated and the preliminary results of the INSURED Project are implemented in a real environment demonstrator composed by pre-operational satellites of a first generation mobile satellite system (IRIDIUM) and a GSM network. The trials carried out with the demonstrator are of paramount importance for the analysis of the feasibility and complexity of the S-UMTS realization. In order to achieve these goals the INSURED project specifies, implements and validates hard and software components necessary to generate appropriate reference models, define the demonstrator architecture and conduct real environment system trials. Incorporating previous definitions of S-UMTS (IMT2000) services and protocols (SAINT, MONET), detailed specifications of appropriate air-interface and network protocols are generated. The validation and optimization process of these specifications supports real trials focusing on propagation, interworking, integration and services issues and, in other cases, by means of simulations using a S-UMTS system simulator. The validation and optimization process, supported by simulation, allows to assess a variety of S-UMTS system specific concepts like adaptive coding and modulation, packet based multiple access schemes, intersegment handover, advanced mobility management (UPT) and resource allocation strategies. The trials execution is related to the availability of the real environment for the demonstrator; the first pre-operational IRIDIUM satellites are available for experimentation. The INSURED project is carried out in the context of trials and is structured in two main trial streams: propagation and integration trials. The outcome of these trials provides valuable information on new approaches regarding S-UMTS architectures and functionalities and provide a basis for further scientific work in the area of integrated mobile communication systems. The following results influencing later scientific work are provided: mobile satellite propagation model (L-band: user link) including bit error patterns gained from L-band LEO satellite propagation measurement campaigns in different environments (i.e. urban, sub-urban, rural, maritime, airborne) and for different user mobilities (i.e. stationary, pedestrian, randomly driving, unidirectional slow and fast motion) reference models of S-UMTS architectures, air interface protocols (e.g. multiple access techniques and radio resource management strategies in S-UMTS) and network protocols and functionalities (e.g. inter-segment handover) formally specified in SDL, implemented in the S-UMTS demonstrator and validated in real environment trials performance evaluation by system simulations of new S- UMTS air interface protocols (e.g. multiple access schemes or radio resource management in S-UMTS) using realistic mobile satellite channel models based on propagation trial results, realistic user mobility models, traffic models and defined S-UMTS architectures specifications of a reference set of services to be used in S-UMTS including parameters like QoS. By defining, specifying, implementing and validating the S-UMTS demonstrator the technical feasibility of the following new concepts and solutions are provided: integration of terrestrial and satellite segments in an integrated system (S-UMTS) - the technical feasibility of designing and operating integrated systems is depicted in a demonstrator; detailed technical descriptions are provided as input to standardization bodies in order to make these technical solutions available to European companies feasibility of seamless inter-segment handover - it is presented that inter-segment handover is possible; 0-7803-4323-9/98/$5.00 copyright 1998 IEEE 1508 VTC ’98