When I was shopping for cellphone service, T-Mobile offered such a product/service which included a WiFi VoIP access point to attach to your home internet connection.
As I understood the product ("Hot Spot Calling"), the mobile phone handset could shift between cellular mode using T-Mobile's conventional cell sites and WiFi mode using your home access point or any other T-Mobile WiFi access point including those which the company had located in public WiFi "hot-spots" like Starbuck's coffee shops.
See:
Another approach to simulating a local micro-site (which works with any cellular carrier and which I tried at my home for a while) is a cellular signal relay such as the zBoost YX510 PCS/CEL.
This consists of an antenna which you locate on your roof or a tower/mast to get a better signal path to existing cell towers in your general area, a length of RF coaxial cable, and a re-transmitter/receiver which you locate inside your house or office where you need cellular telephone service. The device can handle multiple connections and is independent of the particular cell phone carrier so, in effect, it is acts as a micro cell site for you or anyone in your home or office.
The zBoost (and other similar competitors' products) work with both CDMA and GSM phones and operates on both the 800 and 1900 frequencies, so all major carriers and most U.S. cell phones are supported.
See the zBoost website at
regards, Will