Proximity feeding is the simplest technique to achieve wideband response in a microstrip antenna on a thicker substrate. However, the bandwidth is limited on a thinner substrate due to the capacitive impedance offered by the feeding strip. This paper presents wideband designs of proximity fed rectangular microstrip antennas loaded with printed open Ring shape or C-shape resonators, while using a thinner substrate. On substrate thickness of 0.053λg, the proposed design yields a bandwidth of 214 MHz (23.62%) with a broadside radiation pattern and peak gain of 8.0 dBi. Against the thicker substrate proximity fed design, a reduction of ∼ 0.03λg in thickness is obtained. With the obtained antenna characteristics, the proposed design is useful in 800–1000 MHz, GSM band applications.
