Design and Simulation of a Monopole Antenna for Global Positioning System Applications in Handheld Devices

This paper presents the simulation and investigation of a compact monopole antenna optimized for handheld GPS applications at 1576.42 MHz. A key challenge in handheld antenna design is the effect of limited ground plane size on performance. To address this, the proposed antenna was simulated with varying ground plane dimensions (25.00 × 25.00 mm2, 50.00 × 50.00 mm2, 75 × 75 mm2, and 10 × 10 cm2) to evaluate its impedance characteristics, radiation properties, and gain performance. The results show that a ground plane size of 75 mm × 75 mm provides optimal impedance matching, achieving a return loss below -10 dB and a VSWR below 3. Input impedance analysis confirms capacitive dominance at the resonance frequency, further supporting stable antenna performance. Radiation pattern analysis reveals a directional E-plane pattern and an omnidirectional H-plane pattern, with gain improving as the ground plane size increases. These findings demonstrate that the proposed antenna offers efficient performance and stable radiation characteristics, making it a viable candidate for GPS-based handheld applications.