This study presents two new designs of reduced size broadband microstrip patch antennas for ultrawideband (UWB) operation. The suggested antennas are configured by a folded triangular patch’s feeding technique, Vshaped slot, half V-shaped slot and shorting pins. The shorting pins are applied at the edge of structures to miniaturize the size of the patches. The suggested design with the V-shaped slot provides the measured impedance bandwidth (S11˂-10 dB) of 3.91-12 GHz (101.7%) for broadband application. In the suggested design with the V-shaped slot, the wide bandwidth with an acceptable size reduction is achieved. By introducing a suggested half design with the half V-shaped slot, the impedance bandwidth of the proposed half structure is improved from 4 to 17.22 GHz. The half design includes a measured impedance bandwidth of 124.6% with reduced size of more than 93% compared to the corresponding full design and an enhanced measured bandwidth of 23%. The obtained radiation and impedance results show that the suggested designs are applicable for wideband operation. The prominent advantages of the proposed designs include miniaturized sizes, wide bandwidths and stable radiation patterns, whereas their major limitation is a more complex fabrication. Besides, the effects of some basic concepts and surface currents on the suggested structures are investigated to explain their broadband performance.
