This paper presents an investigation conducted on annular ring slot loaded microstrip antenna operating in triple band and it is found to exhibit frequency tunability with the slot angle. Return loss of the proposed antenna has been investigated as a function of slot angle ? with fixed coaxial feed location. It is found that the said parameter of antenna depends heavily on the slot angle ?. Resonant frequency and magnitude of return loss has also been investigated as a function of ?. The variation in resonant frequency for first, second and third resonance is (1. 43GHz to 1. 57GHz), (1. 772GHz to 1. 973GHz) and (2. 557Ghz to 2. 597GHz)and the variation in return loss is (-9. 297dB to -1. 75dB),(-21. 15dB to-27. 25 dB) and (-23. 89dB to-26. 83 dB) respectively. All simulations are carried out using Zeland IE3D software.

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Slot Angle Annular Ring Slot Return Loss Resonant Frequency Triple Band. .