The reception was improved SLIGHTLY in P.R 1.2 so that it won't disconnect that much to Wi-Fi's that are even in close range. So a tweak may be needed.

But in reality, the N9's antenna for Wi-Fi is one of the worst I have ever seen on a phone. The iPhone 4S could detect 7+ N8 is 5 but the N9 only shows 1-2.