In this paper, the theoretical and simulated results of a quad-band patch antenna without any air/foam gap between the dielectric layers are discussed. The design idea uses a skated dielectric layers to achieve a multi-frequency operation. The antenna under study includes four patches patterned on the top of layered dielectric substrates and is stacked vertically. Two pairs of spaced slits are embedded at the patch's radiation edges of the bottom and second patches to adjust the resonant frequencies. The resonant frequencies of the different patches are obtained at 4 GHz, 5 GHz, 6 GHz, and 7 GHz. According to the cavity theory and equivalent circuit approach, a theoretical model of the multilayer stacked patch antenna (MLSPA) is determined. Theoretical and simulated return loss plot is presented to validate the proposed design. The antenna parameters such as radiation pattern, gain, voltage standing wave ratio (VSWR), and beam-width are also discussed. Good impedance matching and radiation characteristics at the four operating bands make this antenna a good candidate for many applications. The antenna simulations are performed using a high frequency structure simulator (HFSS) 15.0 tool.