Reflectarray design for small antenna using meta-surface

In the machine to machine (M2M) communication, the propagation environment is worse than that of usual mobile communications, because the terminal equipment is installed in niche space, such as a gap between pieces of furniture. One solution to cope with the bad condition is to apply a high spec antenna, however, it is difficult to change antenna specification because in most cases it should comply with system standards. Another possible way is to apply reflectarray which can change radiation direction from antenna, but it is also difficult to install the reflectarray close to one-wavelength size antenna, such as dipole antenna. To address the issue, we have studied the control method to direct maximum radiation beam to desired direction using meta-surface whose elements consist of mushroom like structure without via-hole.