A novel single-feed circular polarized slotted loop antenna

A novel single feed circular polarized (CP) slotted loop at L-band for low cost application is reported. This antenna uses a microstrip transmission line to feed a square loop slot on the opposite side of the substrate, two slotted stubs are placed across the diagonal line of the square loop. A wide bandwidth of 11% for less than 3 dB axial ratio (AR) and 10 dB return loss have been achieved.