Wi-Fi® plays a crucial role in the distribution of fixed broadband connectivity in homes, offices, and various other environments. The vast majority (up to 92%) of home internet traffic is connected to the end-user through Wi-Fi. In enterprise settings, Wi-Fi is essential for handling the large amounts of data and simultaneously connecting large number devices with improved reliability, higher data throughput and lower latencies. Governments across the world are prioritising deployment of very high-capacity fixed network infrastructure – but connectivity is only as good as the narrowest bottleneck. In short, Wi-Fi functionality is integral to the modern connected lifestyle in homes, businesses, and public spaces.

Adequate spectrum capacity (bandwidth) is imperative to Wi-Fi performance, ensuring that it does not become a bottleneck that constrains the end-to-end connectivity. The focus of this study is to simulate and analyse the impact of spectrum availability on Wi-Fi ability to support broadband connectivity in the Chinese residential deployments. In some countries up to ten 160 MHz channels2 (three at 5 GHz, seven at 6 GHz)3 are available, while only three 80 MHz Wi-Fi channels (at 5 GHz) are available in China. The simulations presented here model high-density Wi-Fi deployment in a typical residential apartment building with fibre connectivity to every apartment. The model is used to quantify the extent to which Wi- Fi spectrum congestion sets a constraint (i.e., bottleneck) on the connectivity provided by fibre.

The results of this study confirm that the limited Wi-Fi spectrum bandwidth is very likely to impose a bottleneck on residential broadband connectivity. With access to only three 80 MHz channels, Wi-Fi can support 500 Mbit/s connectivity in around 30% of residential building area and only in 3% at gigabit speeds. To ensure whole-building coverage at 500 Mbit/s, a minimum of ten 80 MHz channels are needed with Wi-Fi access to some spectrum in the 6 GHz band.