This paper is an extension of a previously published work concerning a novel approach for the design of RF MEMS switches in coplanar waveguide (CPW) configuration. The peculiarity of the method is to allow imposing the matching condition directly in analytic form. This result is obtained using the image parameter representation for the modeling of the device. Standard commercial simulators are used to develop a comparison among different switch configurations designed by means of the proposed modified approach. The numerical results confirm the validity of the method.