IEEE 802.11 wireless local area networks (also called Wi-Fi) are widely used as Internet access technologies due to its availability, high-speed, low-cost, and standardization world-wide. While the performance of Wi-Fi has been studied and reported extensively in the network literature, the effect of radio propagation models on system performance in noisy channels has not been fully explored yet. This paper, therefore, investigates the effect of propagation models (two ray ground, path loss shadowing, and overall shadowing) over 2.4 GHz and 5 GHz on the performance of a typical 802.11n network in noisy channels. A campus-wide 802.11n network simulation model is developed for the said study using the Riverbed (OPNET) Modeler 18.7. We consider both real-time (e.g. voice and video) and non-real time (e.g. FTP) applications to generate traffic on the network. Simulation results show that FTP download time and FTP upload response times have significant effect on radio propagation models as well 2.4- and 5 GHz channels. However, the effect of propagation models on VoIP packet delays, jitter as well as video delays is found to be insignificant. The findings reported in this paper provide some insights into Wi-Fi performance under noisy channels that can help network researchers/engineers to contribute further towards developing next generation Wi-Fi networks capable of operating in noisy channels.