Crossed dipole antenna with switchable circular polarisation sense

A crossed dipole antenna with a reconfigurable circular polarisation (CP) is proposed. This antenna consists of a pair of L-shape elements with lambdag/4 phase delay lines and DC bias circuits for pin diodes. As the state of the pin diodes mounted between the feeding points and the L-shape elements is changed, the phase sequence of the crossed dipole can be varied. The CP sense of the proposed antenna can be switched with excellent electrical controllability.