BLAST techniques to increase the utilized bandwidth in commercial systems are currently feasible. This paper describes the design of a UMTS prototype, supporting four transmit and four receive antennas, achieving almost four times the capacity of a conventional system. Various parts of the transmitter and receiver are mapped on FPGAs and fast DSPs communicating via a specially designed communication link. The system was entirely designed using C code, embedded in SIMULINK S-functions for simulation, and, after validation, automatically mapped onto the hardware platform.