Microstrip antennas (MSAs) consist of metallic radiating patch on one side of a thin dielectric substrate backed by a ground plane. One of their most interesting applications is that for transmitting and receiving systems, which require circularly polarized radiation. Besides having the advantages of light weight, low cost, compatible with integrated circuit technology, the major limitations of microstrip antennas are their narrow impedance and axial ratio (AR) bandwidth, small gain and low power handling capability. In this paper, we examine how to overcome the limitations of narrow bandwidth and low gain, keeping in mind that axial ratio deviation from circularly polarized radiation is not too great with in the voltage standing wave ratio (VSWR) or impedance bandwidth for VSWR ? 2. Attempts are made to improve bandwidth by optimizing gap coupled microstrip antenna for broadband wireless applications. Multiport network model (MNM) is used to analyze the variations in VSWR and AR bandwidth over range of frequencies on the basis of various substrate parameters. In this paper, we have explained MNM analysis of various singly-fed gap-coupled configurations.