A compact patch antenna using artifitial ground structure with high permittivity substrate

A broadband patch antenna using an artificial ground structure (AGS) is presented. The structure is low-profile with a thickness of 5.1 mm at around 6 GHz, however, more than 24% of the 3-dB axial ratio (AR) band has been obtained. The AR bandwidth of a CP patch antenna is extended because the off-band of AR, which is close to linear polarization, is converted to CP by the AGS structure. In this paper, some brief principle will be discussed. Furthermore, the permittivity of 2.2 of substrate is replaced with higher value of around 10. In this case, the size will be miniaturized. In the last half part of the paper, the effect of the high permittivity on the AR bandwidth is discussed. In conventional cased, the bandwidth will be narrow if the substrate of the patch antenna gets high. However, this paper shows the bandwidth can be kept sufficiently using such high dielectric. Through the discussion, how much the AG is effective to hold the sufficient bandwidth, and the effect of miniaturization is discussed compared to previous results and other publications. As a result, keeping the same bandwidth, the antenna area can be reduced to around 25% cA broadband patch antenna using an artificial ground structure (AGS) is presented. The structure is low-profile with a thickness of 5.1 mm at around 6 GHz, however, more than 24% of the 3-dB axial ratio (AR) band has been obtained. The AR bandwidth of a CP patch antenna is extended because the off-band of AR, which is close to liner polarization, is converted to CP by the AGS structure. In this paper, some brief principle will be discussed. Furthermore, the permittivity of 2.2 of substrate is replaced with higher value of around 10. In this case, the size will be miniaturized. In the last half part of the paper, the effect of the high permittivity on the AR bandwidth is discussed. In conventional cased, the bandwidth will be narrow if the substrate of the patch antenna gets high. However, this paper shows the bandwidth can be kept sufficiently using such high dielectric. Through the discussion, how much the AG is effective to hold the sufficient bandwidth, and the effect of miniaturization is discussed compared to previous results and other publications. As a result, keeping the same bandwidth, the antenna area can be reduced to around 25% compared to other patch antennas compared to other patch antennas.