Development of control board for multifunctional and reconfigurable metasurfaces for 6G wireless systems

Reconfigurable Intelligent Surfaces (RIS) are emerging as a key enabler for future wireless communication systems such as 6G by providing programmable control over electromagnetic wave propagation. These surfaces, composed of arrays of passive or active metaatoms, can dynamically reflect, steer, and modulate incident signals to improve coverage, reduce latency, and enhance spectral efficiency. This thesis presents the design and simulation of a scalable 2-bit RIS control system capable of performing high-speed modulation and real-time beam steering across large metasurface arrays. The system is architected in two distinct layers: modulation layer handles high-frequency binary modulation using low-resistance MOSFET switching, while beam steering layer implements beam steering using 36 cascaded SN74HC595 shift registers controlling a total of 288 output lines. The control logic is executed on the PYNQ-Z1 FPGA platform, which provides the necessary signal integrity and timing precision to support 5 MHz switching for all RIS elements. The methodology includes modular PCB design using KiCad, signal timing validation through oscilloscope measurements, and SPICE-based current simulations to ensure each diode receives 10 mA as required. Comparative analysis with Arduino-based control shows significant improvements in waveform quality and driving capability when using the FPGA. The implementation meets the stringent performance criteria for RIS operation, proving the feasibility of the proposed control structure for dynamic and programmable wireless environments. This work contributes a verified and modular control architecture that is ready for future experimental integration into full RIS testbeds.