Wireless Bridge from ISP Modem/Router to Time Capsule

I have a modem/router that is provided by my ISP which acts as the wireless access point for all devices in my house. Unfortunately, due to it's location, there is a portion of the house where the signal is weak or non-existent. I have recently picked up a new time capsule and use it for wireless backup purposes. Is it possible to continue to use it for wireless backups and also place it in an area of the house to use it as a bridge to extend the existing wireless network range of my ISP modem/router? I'm assuming then I could continue to connect as normal to my wireless network with various devices, but in the weaker areas of the house the time capsule will allow for a stronger signal/connection. Thanks.