Khaled Fazel Stefan Kaiser Radio System Design DoCoMo Euro-Labs Marconi Communications Landsberger Strasse 312 D-71522 Backnang, Germany D-80687 Munich, Germany The field of multi-carrier and spread spectrum communications has became an important research topic with increasing number of research activities [1]. Especially in the last two years, beside deep system analysis of various multiple access schemes, new standardization activities in the framework of beyond 3G (B3G) concepts have been initiated. Multi-carrier transmission is considered to be a potential candidate to fulfil the requirements of the next generation system. The two important requirements of B3G/4G can be summarized as: i) much higher data rate for cellular mobile radio and ii) a unique physical layer specification for indoor/hot spot and outdoor/cellular applications, including fixed wireless access (FWA) schemes. The activities within the 3GPP and WiMAX fora are examples of such trends (see Fig. 1). IEEE 802 ETSI WAN UMTS, EDGE 3GPP (GSM) HiperMAN & IEEE 802. 16 WiMAX MAN HiperAccess WirelessMAN HiperLAN/2 IEEE 802. 11 LAN WiFi RLAN WirelessLAN IEEE 802. 15 PAN Bluetooth BRAN Figure 1 Beyond 3G: Worldwide Standardization Activities xii Editorial Introduction The WiMAX (Worldwide Interoperability for Microwave Access [2]) vision is to provide broadband wireless access with its primary goal to promote IEEE 802. 16a-e and ETSI-BRAN standards through interoperability testing and certification. In the first step the broadband access to the so-called last mile applications with fixed positioned terminals is envisaged.

Stefan Kaiser was the first researcher to address the institutional and legal aspects of the future air navigation systems in a pioneering thesis presented to the Institute of Air and Space Law, McGill University.