Asymmetric Triangular Semi-Elliptic Slotted Patch Antennas for Wireless Applications

Abstract

Microstrip radiators with Circular Polarization (CP) are paid much attention in wireless and navigational applications. In this paper, four microstrip rectangular radiators with axially centered asymmetric Triangular-Semi Elliptic (TSE) slots along the square boundary of the patch is proposed. The probe feed is applied along the diagonal of the square patch and it is optimized for its position to get CP radiation. The first Asymmetric Slotted Patch (ASP#1) of 50 mm X 50 mm provides 10dB RL (Return Loss) bandwidth of 200 MHz (2320 to 2520 MHz) with CP and 3dB AR (Axial Ratio) bandwidth of 40 MHz with a gain of 3.3dBi. A 10dB RL bandwidth of 340MHz (2320 to 2660 MHz) with CP and 3dB AR bandwidth of 60MHz (2370 to 2430 MHz) with a gain of 3.8dBi is obtained for second Asymmetric Slotted Patch (ASP#2) of 50 mm X 50 mm. The scale down versions of ASP#2 presented are ASP#3 (40 mm X 40 mm) and ASP#4 (30 mm X 30 mm) suitable to operate in IEEE 802.11y (3.65-3.7 GHz) and 802.11a (5.2 GHz) Wi-Fi applications with CP radiation. The proposed ASP#3 offers 10dB RL bandwidth of 390 MHz, 3dB AR bandwidth of 100 MHz and a peak gain of 4.3dBi with CP. ASP# 4 offers 10dB RL bandwidth of 590 MHz, 3dB AR bandwidth of 160 MHz and a peak gain of 3.95dBi with CP. It is evident from the results the proposed ASP#1 and ASP#2 are suitable for WLAN (2.4 GHz) and ISM (2.4-2.483 GHz) band applications. All the proposed four antennas are fabricated, measured results are compared with the simulation results.