RF MEMS-reconfigurable architectures for very large reflectarray antennas

The problem of very large reconfigurable reflectarray (RA) antennas based on RF MEMS technology is addressed in connection with a 77 GHz RA for imaging application being developed within the European FP7 project called ARASCOM. Since thousands of reconfigurable elementary cells are employed, reducing the number of tuneable components is of paramount importance for the practical realization of the reflectarray. A dramatic reduction of the number of tuneable devices is shown to be achievable without performance degradation by a proper architecture based on 1-bit digital phase shifting and on the separable illumination of the RA. The elementary cell design, the fabrication technology and the control network architecture are illustrated in some detail showing the feasibility of the approach proposed.