3-Sector Cell vs. Omnicell: Cell Sectorization Impact on the Performance of Side-by-Side Unlicensed LTE and 802.11ac Air Interfaces

Abstract

Due to the benefits of networks coexistence, it is common nowadays to equip mobile phones with two types of network interfaces: LTE and 802.11ac. However, using the same 5GHz bandwidth by 802.11ac and LTE in unlicensed spectrum, along with the structural differences of the two networks, result in multiple coexistence limitations and implementation issues. Considering the potential benefits of cell sectorization over the conventional omnicells for improving the performance of LTE users, can they achieve similar improvements in coexisting networks. Moreover, can LTE signals interfere and affect the performance of 802.11ac users coexisting with LTE. In this case, which LTE cell deployment, either omnicell or sectorized cell, has the most impact. Toward addressing these issues, this work proposes a link-level and physical-level model. The model consists of two distinct LTE sites: a conventional omnicell site (360 degrees) and a threesector site (3 × 120 degrees). In addition, the model contains two similar 802.11ac networks, one for each site, to coexist 802.11ac Wi-Fi stations with LTE users. The model is further optimized to include a pure 802.11ac network, dedicated as the baseline. Subsequently, the model is verified in NS3 through various simulation scenarios by means of measuring and quantifying the three-sector, omnicell, and pure 802.11ac networks performances to facilitate resolving any doubt of mobile operators and developers regarding the cell sectorization and coexistence issues. The simulation results indicate that in coexisting networks, LTE users in omnicell sites attain better performance than users in 3-sector sites, while the performance of 802.11ac users varies when different features are combined.