Design principles for ultra-dense Wi-Fi deployments
Future indoor networks need to provide broadband services either by increasing bandwidth, using higher order modulations and high spatial reuse. To this end, ultra-dense Wi-Fi networks need to be deployed. This work discusses the challenges of ultra-dense Wi-Fi networks, where inter-AP distances are 5 m or less, and discuss necessary requirements to maximize the high spatial reuse of radio resources through the use of adaptive Clear Channel Assessment (CCA) thresholds and downward facing directional antennas. We also examine the significant impact of uplink transmissions, and present the necessary uplink transmit power control in ultra-dense deployments to avoid the interference coming from hidden nodes in neighboring APs. With the proposed techniques and antennas in place, we show that the limitations placed by high contention and interference in ultra-dense deployments can be overcome to provide over 8 χ gains in downlink throughput when compared with APs with omni-directional and unadjusted CCA thresholds.