In this paper, a novel configuration for linearly polarised Dual Frequency Microstrip Antenna at S- and X-bands is presented. The proposed configuration utilises the frequency ratio of 1:3.3 between the two bands to its advantage by saving space. It uses the antenna at S-band as ground plane for a 2 x 2 antenna array at X-band without any additional requirement of separate space and ground plane. The patches are electromagnetically coupled to give measured bandwidth (|S11| <-10 dB) of 13% at S-band and 6.2% at X-band. It gives isolation better than 38 dB over the entire bandwidth of the two frequency bands. The measured antenna gain is 7.5 dB at S-band and 10.5 dB at X-band.
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