iPhone 4s unable to connect to wifi

My iphone 4s is unable to connect to my home wifi. It was working fine just a few days ago, and the rest of my family's iphones, which are all iphone 5's, are having no problem with connecting. My phone cannot identlify the network that everything else in the house is connected to. It does connect to other networks, but oscillates bewteen wifi, 3G, and the circle which indicates no data. This problem has been going on for a few days and I don't know what to do, as it seems more like a phone problem than a network problem, since every other device is working without any glitch. Suggestions?