This is the GSM Antenna not the WIFI as indicated in the tutorial.
The WIFI and GPS antenna is at the top of the iPhone near the cameras.
FYI if anyone has weak wifi and GPS signal then a small metal tab has come off the EMI shield in the top most hole with the 5 screws, I had a problem with weak WIFI after changing the screen and the found that this was the cause, the little tab had come off the EMI shield when I had removed it.
Lorsqu'il en aura reçu, il pourra afficher un graphique de sa réputation au fil du temps.
Voici un aperçu de ce à quoi ressemble ce graphique :
Aucun point de réputation obtenu pour l'instant.