I was having problem connecting and disconnecting to my D-Link DIR-615 router. I tried lots of things but nothing made any lasting difference until I did this....
The 802.11 mode was set to "Mixed 802.11n, 802.11g and 802.11b"
I changed this to "Mixed 802.11g and 802.11b" and now have a perfect, rock-steady WiFi connection.
I think the "n" standard was not defined properly when this router was purchased, and obviously it causes a problem with the TouchPad.