This paper presents a novel approach for bandwidth enhancement and gain improvement of a microstrip patch antenna array for IEEE 802.16a 5.8 GHz Wi-MAX applications. A split ring resonator (SRR) has been designed to load the microstrip patch antenna array. The unloaded antenna array resonates at 5.8 GHz with gain of 4.3 dBi and bandwidth of 425 MHz, whereas when loaded with split ring resonator the gain approaches to 5.7 dBi and bandwidth increases to 610 MHz which corresponds to bandwidth enhancement of 3%. The electrical dimension of the patch is 0.23λ x 0.3λ.
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