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Top1. Introduction
Wireless Local Area Networks (WLANs) based on the IEEE 802.11n networks are hugely popular and widely deployed in residential environments. Availability of many Wi-Fi enabled devices (e.g. smart phones) enable the users to use multimedia applications (e.g. streaming music and movie videos) from the comfort of their homes. The demand for multimedia content is increased because of the popularity of streaming services such as You Tube, Netflix etc. (Saleh, Shah, & Baig, 2013; Saleh, Shah, & Baig, 2015; Akbar, Saleem, Khaliq et al., 2014). Also many home users demand High Definition (HD) videos that further increase the need of high data rate. To meet this increase in demand of high data rate IEEE 802.11ac standard is proposed (Ong. et al., 2011; Perahia, & Stacey, 2013; Vaughan, & Steven, 2010).
IEEE 802.11ac is the fifth generation WiFi standard that has many new and advanced features than the previous IEEE 802.11n standard. IEEE 802.11ac only uses 5GHz frequency band unlike IEEE 802.11n that uses both frequency bands of 2.4GHz and 5GHz. IEEE 802.11ac supports 256 Quadrature Amplitude Modulation (QAM) which is not present in IEEE 802.11n. Also, 80MHz channel width is mandatory for IEEE 802.11ac which is different than IEEE 802.11n that supports a mandatory channel width of 20MHz. Another difference is that IEEE 802.11ac supports 8 spatial streams which are more than IEEE 802.11n that supports only 4 (Ong. et al., 2011; Perahia, & Stacey, 2013; Vaughan, & Steven, 2010). With all these features IEEE 802.11ac promises higher data rate than IEE 802.11n. However, IEEE 802.11ac enabled wireless routers are much costlier than the IEEE 802.11n routers (Smith, 2013). This price difference may make the IEEE 802.11ac unattractive to home users. If IEEE 802.11ac provides much higher data rate than IEEE 802.11n then spending more money on deploying IEEE 802.11ac in home environment may seem justified to home users. Therefore, it is of utmost important to clearly analyze and compare the performance of both standards in a typical home environment. Another important factor to analyze is the effect on average throughput by increasing transmit diversity on the wireless router. More number of antennas are recommended on the wireless routers than the wireless devices because of issues associated with cost and power (Mihovska, & Prasad, 2009). It is interesting to anlayze the effect of increasing transmit diversity in a residential home environment that provides a complex multipath fading environment.
Many studies exist in the current literature that carry out throughput analysis of WiFi standards in an indoor environment (Narayan, Jayawardena, Wang, Ma, & Geetu, 2015; Shah, Rau & Baig, 2015; Dama et al., 2011; Chen & Law, 2007; Zeng, Pathak & Mohapatra, 2015). Narayan et al. (2015) carry out experiments to compare throughput gain provided by IEEE 802.11ac compared to IEEE 802.11n over both UDP and TCP. In (Shah et al., 2015), performance analysis of both IEEE 802.11ac and IEEE 802.11n is carried out in an indoor environment with interference. Dama et al. (2011) carry out experiments in an indoor environment and compare the throughput obtained by IEEE 802.11n network in both 2.4GHz and 5GHz. Experiments are also performed in (Chen & Law, 2007) to measure the throughput obtained by IEEE 802.11b network. Similarly, in (Zeng et al., 2015) authors carry out experiments to study the impact of larger channel width in IEEE 802.11ac on energy efficiency and interference.