You need to set up ssh without offering a passphrase. How to do this?
go to the
ssh-keygen -t rsa
accept the default location .ssh/id_rsa and .ssh/id_rsa.pub
then do (empty passphrase)
and now you can use the generated file .ssh/id_rsa.pub
scp .ssh/id_rsa.pub distal.host.ip.address:/home/yourid/.ssh/authorized_keys
(of course we are coming from only one preimage, otherwise just add line to authorized_keys