Cell phones often do not work well in rural areas for a number of reasons. Here are some of them and how you may fix bad cell phone reception.
Recognize that the causes of poor cell phone reception are many and therefore no one remedy will fix all problems. There are a number of things that cause bad cell phone reception in rural areas. One is that cell towers, due to lack of enough revenue, are spaced farther apart. Obstacles such as trees and mountains may block your phone's signal from reaching a distant cell tower.
Determine if you are using a PCS or regular cellular carrier. With the exception of Nextel most cell phones are either PCS (1900 Mhz) or Cellular (800 MHZ). Most phones use a mix of the two except for ones that are PCS only such as T-Mobile. PCS phones do not work very well out in rural areas because the 1900 MHZ signal only reaches barely beyond the line of visual sight, or ten miles or less to a tower. Cellular and PCS companies simply cannot install enough towers for PCS phones to work as well as cellular.
Find out what service most people are using in your area if you have just moved out to the country and choose that carrier. Next you can install a booster amplifier in your vehicle and home. These devices boost your cell phone signal up to the FCC's limit of three watts. Newer boosters can work wirelessly with an interior antenna and an exterior antenna combination that receives your phone signal and re amplifies it. In some cases just a simple magnetic mount antenna will do the trick. Look for one that has a high DB gain. These high gain antennas will usually be longer than 6 inches and contain a coil or plastic cylinder that electronically "lengthens" the antenna. Unfortunately many new phones do not have antenna jacks any more and the passive, patch type adapters do not work as well. A repeater type booster may be your only option and it is important to remember that there are some places where no booster or antenna will do any good since the cell phone signal is nonexistent.
In some areas cellular signals are so weak no booster or amplifier will do any good.