reception

Background: A couple years ago 4 metal grain silos with the typical conical roofs were built to the West-northwest of me - the most NNE of those is right in the direction most of my desired (to view) OTA TV stations are at. One of these stations is 7 miles from me with a 1692 ft. tall tower...

Hello, the attached is a 4g wifi device however where i live the cell tower signal is very weak, how can i attach external antenna to it for better cell reception and hence better 4g speed