Can i use my Wi-Fi signal to make calls on iphone 4?

Where I live I have HORRIBLE connection problems(luck to have 1 bar) but I mainly use my phone right next to my wireless router which my phone picks up the signal great. How can I use this signal, if possible. Do i have to jailbreak the phone first?

Some providers can provide a device that connects to your home's broadband service to give you better reception. On Sprint it's called an Airave; on Verizon it's called Verizon Network Extender; on AT&T it's called the 3G Microcell; on T-Mobile it's called T-Mobile Hot Spot @Home, which you connect to your home broadband and essentially turns it into a mini cell site. They may charge you, but if you plead your case to the company, they may give it to you for free, since service in your area is bad.