Wifi Keeps Going Out

starting last week, my Wi-Fi signal keeps going out every hour on the hour.  It will go out at the same time: 9:42am, 10:42am, 11:42am, 12:42pm, etc....The Wi-Fi Signal will go out on all of our devices: lap top computer, tablet, cell phone, our wi-fi enabled blu-ray player.  It will go out for 30 seconds to a minute and then it will reconnect.   I have an Xfinity Router/Modem combination made by Arris Interactive Model TG862G/CT.  Can you please give suggestions?