In this paper the architecture and the design of a System-on-Chip (SoC) demonstrator for a Multicarrier-CDMA (MC-CDMA) based beyond 3G mobile radio system using multiple antennas will be presented. This development is performed in the scope of the European IST project 4MORE (IST-2002-507039, 4G MC-CDMA Multiple Antenna System on Chip for Radio Enhancements) together with 11 European partners from six countries. The main goal of the 4MORE project is the demonstration of a base band system-on-chip (SoC) implementation of a potential future mobile radio system. The SoC architecture is based on a Network-on-Chip (NoC) approach including an ARM based MCU subsystem.