I have a friend isolating in a temporary rental with poor wi-fi. He can barely get a signal and has to place his laptop awkwardly to get it to work at all. It is weak and unreliable.

In the past I experimented with reflectors made of aluminum foil on curved cardboard to improve wi-fi signal to a dongle. This works to some extent with a dongle. The challenge is how do you do this with an entire laptop? Can anyone calculate the dimensions of a reflector that could be placed behind the computer? This is way over my head.