wifi connection not searching automatically and reconnecting

[Jon Grant]

Hi. i am using latest kubuntu and finding that my wifi establish net
connection when i login or reconnect if it looses the connection.  Any
ideas how I can achieve this? the KNetworkManager seems very basic
without such options, and network-admin doesn't have the setting
either.

Kind regards, Jon

I am in "roaming" mode:

my /etc/network/interfaces only contains this:

auto lo
iface lo inet loopback