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A compact coplanar waveguide (CPW)‐fed convex hexagonal‐shaped ultrawide band (UWB) antenna, with L‐shaped thin ground plane for lower frequency band stop function and tapered rectangular vertical slot in radiating patch for upper frequency band stop is presented. The proposed antenna of dimension 40 × 22 × 1.6 mm3 provides good impedance matching over dual operational UWB resonating at 5.4 and 9.6 GHz with fractional bandwidth 69.54 and 33.83%, respectively. The lower frequency stop band in the vicinity of 2.4 GHz and higher frequency stop band in the vicinity of 7 GHz has bandwidth of 3.17 and 1.8 GHz, respectively, to avoid the interference of PCS, GSM 800/1900, ISM, WLAN, and X‐band satellite uplink (7.25–7.75 GHz) and downlink (7.9–8.4 GHz) communication system. The E‐plane radiation pattern observed is bidirectional in nature due to CPW feed and that of the H‐plane pattern is omnidirectional. The resonating lower and higher UWB achieves the peak gain 2.16 and 6.5 dBi, respectively. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:1045–1049, 2013; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.27470

In this paper, the refined beam theory (RBT) is examined for the bending of simply supported isotropic, laminated composite and sandwich beams. The axial displacement field uses parabolic function in terms of thickness ordinate to include the effect of transverse shear deformation. The transverse displacement consists of bending and shear components. The present theory satisfies the traction free conditions on the upper and lower surfaces of the beam without using problem dependent shear correction factors of Timoshenko. Governing differential equations and boundary conditions associated with the assumed displacement field are obtained by using the principle of virtual work. To prove the credibility of the present theory, we applied it to the bending analysis of beams. A simply supported isotropic, laminated composite and sandwich beams are analyzed using Navier approach. The numerical results of non-dimensional displacements and stresses obtained by using the present theory are presented and compared with those of other refined theories available in the literature along with the elasticity solution.

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