As the technologies of the Internet era permeate daily life, the expectations and needs of Internet applications explicitly increase. Instead of communicating using letter mails and phone calls, people now prefer video streaming. And the young generation most likely plays computer games. However, they sometimes complain about the Internet latencies [2] and slow network [3], which is mainly caused by packet loss. Packet loss is the loss of data during the process of digital communication transmission [4]. For a wireless network like WIFI, the packet loss is expected to increase as the increment of the distance [5]. High qualities of Internet communication, or in other words, stable and fast signal transmission, is significantly commanded to ensure a lower rate of packet loss. In this report, we will use the ns-3 network simulator to establish propagation models of signal transmissions. The propagation loss models will simulate the received power concerning the input power and transmission distance. Various models with different algorithms will be tested and compared. We expect to possess a deeper understanding of the reasons why packet loss occurs more frequently as the transmission distance generally increases.