In order to accommodate the phasing circuitries inside the reduced available area embedded in the unit cell, the antenna stratification layers are properly modified by choosing a higher permittivity for the phasing line substrate.
In order to allow the accommodation of the tuning circuitries in the smaller area embedded into the unit cell, the phasing line substrate adopted in  is properly substituted with a dielectric layer with [[epsilon].sub.r] = 6 and thickness h = 0.762 mm (see Table 1).
The radiating structure design is performed by a proper tuning of patch and slot sizes, with the aim to satisfy the resonance condition as well as the matching between the patch and the phasing line, at the operating frequency of 11.5 GHz.
As a matter of fact, Figure 5(b) shows that for any fixed value of [L.sub.s], the section [L.sub.v] can be chosen to shift the phase curve within the capacitance range with the aim to increase the allowable phase tuning range, so obtaining a phasing line acting as a 360[degrees] phase shifter.
The depicted diagrams refer to the reflectarray element with a phasing line having dimensions [L.sub.v] = 4.2 mm and [L.sub.s] = 5.2 mm.