Effects of bending GPS antennas

The effect of antenna bending on return loss, impedance bandwidth, and radiation pattern is studied, taking four antennas as examples. These include a patch, slot, inverted-F, and dipole antenna. Some of them exhibit circular polarization and one is broadband. Impedance is seen to be fairly constant regardless of bending, though if circular polarization is excited by careful antenna shaping, the circular polarization and corresponding resonance are easily lost. The axial ratios of all examined antennas degrade quickly with decreasing bend radius. Linearly polarized antennas are more tolerant to bending effects, though their polarization may twist and main lobe direction change.