My wireless network seems to be working properly now, it has been working
without any deconnection during several hours and after been rebooted several
times. I cannot explain but only write what I have done.
While I was still connected by "wicd" I quickly installed the basic
"network-manager" from "System" "Administration" "Synaptic packets manager" and
by the same way uninstalled "wicd". I waited around one hour before
rebooting.The wireless network opened before by "wicd"
did not close anymore as "wicd" had totally been removed (configuration files
included) from the computer, my wireless connection was rock steady for the
first time.
I then rebooted to check the newly installed "network-manager". No joy, it did
not connect. I made a few "sudo stop network-manager" and "sudo start
network-manager" without seeing any network-applet in the tray.
I rebooted again and without any explanation the network-applet was in the tray,
it was trying to connect, it did it and has been since that time rock steady. I
did a few reboots yesterday and also this morning with the same nice result. Now
my /var/log/messages and /var/log/syslog show nothing wrong.
I then cleaned all these files which had been edited during my attempts to get
the thing working, like /etc/network/interfaces, which is now the very basic
auto lo
iface lo inet loopback
without anything else.
I also did not try to add any other program like "wifi radar" as I did before
and I won't try to use again "wicd" which may have been responsible for these
problems, I am not sure but I do not want to change again a system which is
currently working properly.