While people who live close to television-broadcast stations have their pick of antenna types, those who live in rural areas have fewer choices. Exactly what options are available depends heavily on the distance to the transmitter tower as well as local terrain and the transmitter's power. In the end, the consumer must consider the signal strength at his location to determine the best antenna.
There are many different models of outdoor antennas, however, most fall short when considering rural conditions. Multi-directional and "smart" antennas can receive signals from all directions, however, they need strong signals to be effective. Directional type antennas focus all of their capability in a single direction, at a single station, and are the best concentrators of television signals. The directional family of antennas is the best choice for people living in rural areas (References 1, 3 and 4).
Small directional antennas are constructed of metal elements resembling a collection of small tubes held together by larger tubes. They are very good in areas that are not low-lying, where line of sight between the antenna and the transmitter is relatively flat, and signal strength is fair to good. They are especially good at receiving lower-band VHF stations (channels 2 through 6) but still good at picking up the higher-band stations. Using a signal amplifier with these antennas will improve their performance in fair-signal areas (References 1 and 3).
Significantly larger than the small directionals, these are the most popular rooftop antennas in the U.S. They are made of many metal elements and have excellent "ghost" reducing capabilities. Medium directional antennas can receive slightly weak signals and concentrate them to usable levels. With a signal amp installed, these antennas can work to well in a weak signal range. In some conditions, they will pull in stations all the way to the edges of very weak signal areas (References 1, 2 and 3).
Similar in construction to the small and medium directional antennas, only much larger, large directional antennas are literally the end of the line for antennas. They can easily pick up stations in fairly weak reception areas and are the antenna of choice anywhere it's difficult to receive broadcast television. When coupled with a signal amplifier, a large directional antenna can be effective even in very weak signal areas. If a large directional antenna cannot pull in a station, the signal is simply too weak for any off-the-shelf antenna to work (References 1 and 3).