Beam-scanning improvement of reflectarrays by reducing the cell size at millimetre waves

Most reflectarrays use a half-wavelength cell size. In this paper, we present a new reflector-antenna configuration that provides beam scanning and gain improvements by reducing the size of the cells. Small reflectarrays with cell size lambda/2 and lambda/4, respectively, have been designed at 94 GH7. The measured lambda/4 reflectarray at 94 GHZ achieves a beam scanning angle of 60 degrees with a loss of gain of 1 dB, whereas the lambda/2 one exhibits a loss of 3 dB. Numerical simulations show that the improvement does not appear significant below the limit of lambda/6. (c) 2006 Wiley Periodicals. Inc.