We see this drop if the SSID is hidden or there are too many other routers in the same area and channel so armed with this, did you try not hiding and changing the channel?
Also I swap out the router if that does not help.
I have a Belkin Wireless N router which I've had for over a year. For the past several weeks, devices (iPhone, television, laptop, Android phone) are all unable to connect wirelessly to the router. The wired connection works fine. All devices see the connection; some are able to maintain a connection for a brief period (10-15 minutes).
I've tried changing several settings on the router to no avail. Recently, I went ahead and reset everything back to factory settings to start over. I did download a WiFi analyzer on my Evo which did suggest I had a lot of interference on a particular channel. Currently, I have the router broadcasting in b g and n, 20/40 MHz bandwidth, security mode is WPA/WPA2-Personal. Any suggestions on where I should start with troubleshooting?