Microstrip Antenna Design H-Shaped Planar Array 4 Elements Using Circular Slot for Fixed WiMAX Network 3.5 GHz Frequency

Fixed WiMAX network access requires Customer Premise Equipment (CPE) that uses small and easy to integrate antennas. This research will design a 4 element microstrip antenna using an H-shaped patch with the addition of a circular slot in the center. Antennas are used for fixed WiMAX CPE applications at 3.5 GHz (3.4-3.6 GHz) working frequency. The substrate used is FR4 with dielectrics constant 4.4 and Duroid with dielectrics constant 2.2. The feeding technique used is microstrip line. Determination of antenna dimension is done by using mathematical equation. Result design using software simulation obtained VSWR antenna using FR4 was 1.013, return loss -43.803 dB and gain 4.7083. While VSWR antenna using Duroid substrate was 1.015, return loss -42.5923 dB, and gain was 8,486 dB. Characterization of rectangular and circular slot sizes affects the working frequency range. Antenna with FR4 substrate has optimal working frequency on rectangular stripe characterization of 4 mm, 4.5 mm, and 5 mm width with 2-3 mm slot size variation. Duroid substrate design antennas have optimal working frequency with rectangular piece characterization of 5 mm, 5.5 mm, and 6 mm and variations of 4 - 5 mm slot size.