I'm not sure exactly the question, none the less satellite can be volatile at any rate, your tests show typical satellite evening hour squash.
Unfortunately there is likely little that can be done about this.
However there are several users here at testmy.net who are well versed in tweaking your type of connection.
My suggestions would be to insure there are not addons in your browser causing unnecessary traffic, (constant updating ect) and make sure there are no issues on the machine with items such as malware.