Synthesis technique of double-ring slot antenna with tree-shaped coupling strip for dual broadband applications
A synthesis of double-ring slot antenna with tree-shaped coupling strip for 2.4/5 GHz dual broadband applications is presented in this paper. Based on analytical equations, the inner circular disc depicts the operation range of 2.18–2.70 GHz (21.3%) and two concentric slot rings with split-mode couplings determine the desired bands of 4.93–5.96 GHz (18.9%). A novel tree-shaped coupling strip with branches to couple the inner circular disc and with leaves to couple the double-ring slot respectively is proposed to enhance the response of dual bands simultaneously. The obtained frequency responses cover the required bands of IEEE 802.11b/g (2.4–2.484 GHz) and IEEE 802.11a (5.15–5.95 GHz) for WLAN applications. Simulation and experimental results with frequency responses, radiation patterns and Poyting vector distributions are presented and discussed.
