A Planar End-Fire Circularly Polarized Antenna Based on Electric and Magnetic Complementary Dipole for Mobile Terminals

A planar end-fire right-hand circularly polarized (CP) antenna for mobile terminals is designed. The TM010 mode based on half mode substrate integrated waveguide (HMSIW) as magnetic dipole, three broken slots are added to the metal frame as electric dipoles, and the feed network is designed by Wilkinson power divider and phase delay line. Its size only 0.38λ×0.32λ ×0.01λ (λ=189mm). Compared with the traditional design, the proposed end-fire CP antenna incorporates the real structure of the mobile terminal and the simulation results are more consistent with reality. The simulation results show that the gain is -3.5dBic at 1585MHz. The 10dB impedance bandwidth, 3dB axial-ratio (AR) bandwidth and 3dB gain bandwidth are satisfied in 1560 to 1630MHz (4.4%). It covers the b1-band of Beidou-2 (1561.098MHz) and Beidou-3 (1575.42MHz), and can be used for satellite communication and positioning of intelligent mobiles.