Phase-shifting cell loaded with variable capacitances for dual linearly polarised reflectarrays

A new dual linearly polarised phase-shifting cell for reflectarray applications is presented. It consists of two orthogonal sets of parallel rectangular slots etched in a ground plane. Each set may be loaded with a combination of variable and fixed capacitances to provide a reconfigurable 2-bit phase-shifter for both polarisations. A passive version of the proposed cell has been fabricated and characterised in C-band with four fixed states. For each polarisation only two variable capacitances are needed in order to control the phase of the reflected wave.