A Triangular Dual-Band Patch Antenna with Harmonic Frequencies Suppression

Microstrip patch antennas with various shapes and performances are often used due to their inheritance characteristics such as low-profile, ease of installation, low cost, and capability for multi-band operation. However, due to its other characteristic in generating harmonic frequencies, it is necessary to give more attention to these frequencies to avoid interfering with the desired ones. This paper presents the design and characterization of a triangular dual-band patch antenna with arc slot insertions for harmonic frequency suppression. The proposed antenna is intended to work at the frequencies of 0.91 GHz and 2.45 GHz for radio telemetry communication applications. It is designed on a 1.575 mm thick FR-4 epoxy dielectric substrate with a relative permittivity of 4.3 and dimensions of 140 mm × 120 mm. The result shows that by insertion of arc slots, the suppression of second, third and fifth frequencies reaches up to 0.51 dB, 2.55 dB and 3.35 dB respectively. Whereas, the coefficient reflection of the dual-band is maintained less than -10 dB.