Wi-Fi Scaling and Performance in Dense Frequency Planned Networks

The area capacity scaling of Wi-Fi has been thought to be poor due to the 802.11 MAC enforcing single transmissions in overlapped cell coverage areas. This is based on the assumption that the energy detection and virtual carrier sense MAC mechanisms at every station correctly detect ongoing transmissions and thus prevent new transmissions. However overlapped or faded packet headers can cause stations in different cells to lose synchronization with each other. When the overlapped transmissions are in different cells the spatial frequency reuse may increase the area capacity. Area capacity improvement due cell densification is investigated numerically assuming a large indoor frequency planned network with fading and packet capture. For comparison, Wi-Fi and LTE base stations are placed at the same cell centers. LTE area capacity grows faster as it is only constrained by SINR. Wi-Fi area capacity grows slower limited by decreasing SINR and the partially operational virtual carrier sense.