As the demand for mobile data traffic increased significantly in the past few years, the Mobile Network Operators (MNOs) are considering different solutions to increase the network capacity. Since the licensed spectrum is scarce and expensive, deploying LTE in the unlicensed band can be a promising method to accommodate the market need for mobile data. However, LTE has to coexist with other heterogeneous network, especially WiFi, preexisting in the unlicensed medium. This coexistence can introduce a significant performance degradation for currently deployed WiFi networks. In this study, emphasis is given in analyzing the performance of WiFi and LTE coexistence scenario both analytically and through simulation. To this end, a number of solutions are proposed to increase the performance of WiFi.