Small size wideband microstrip patch antenna with horizontal slot and vertical slot in patch stacked patch and multiple patch is fed through microstrip line is presented. By inserting slot on patch, stacked patch supported by wall and the multiple patch, the bandwidth can improve significantly without significant change in the frequency. The bandwidth before adding the slot and the stacked patch was 5%, whereas after adding the slot and the stacked patch the bandwidth increased ranging from 2.42 to 2.50 GHz. The radiation pattern has acceptable response at both E-plane and H-plane. The ground plane size is 56 mm by 74 mm, the antenna designed is based on FR4 substrate with dielectric constant 4.4.For all that, the design of a microstrip antenna is not always an easy problem and the antenna designer is faced with difficulties coming from a) the inherent disadvantages of a printed resonant antenna element, for example the narrow impedance bandwidth, and b)the various requirements of the specific applications, which concern the operation of the radiating element, and cannot be satisfied by a printed scheme with an ordinary configuration[3]. Moreover, the rapid development in the field of Land Mobile Telephony as well as in the field of Wireless Local Area Networks (WLANs) demands devices capable to operate in more than one frequency bands [4].

Bandwidth, gain, offset, stacking Broadband microstrip antenna

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