A low profile transmitarray architecture composed of four profiled focal sources and a flat-lens array is discussed in this paper. The flat-lens is a square array with 2116 unit-cells disposed on a 46x46 element regular grid. Considering the proposed focal system, the focal distance is equal to 44.6 mm (F/D ratio equal to 0.39), which must be compared to a F/D ratio equal to 0.7 corresponding to the case of a transmitarray with classical focal sources with a gain of 10 - 12 dBI. The flat-lens array is based on seven unit-cells with a relative phase-shift around 45° and a transmission coefficient high than -1.9dB in the frequency band 57-66 GHZ (14.6% at 61.5 GHz). The full-arry has been optimized using an ad-hoc tool and results compared to full-wave simulations. A maximum gain of 36 dBi has been obtained including the impact of the waveguide power divider. The 1-dB and 3-dB gain bandwidth are equal to12.4% and 23.2%, respectively.
展开▼
