What is the range of UHF radios?

UHF radios are an important tool in many industries including but not limited to transportation, construction, security and emergency services. When we are picking out a walkie-talkie. A frequent concern is how far can my UHF two-way radio reach? Find out more about this today.

First of all, what is UHF radio?

Ultra high frequency (UHF) is the ITU designation for radio frequencies in the range between 300 megahertz (MHz) and 3 gigahertz (GHz), also known as the decimetre band as the wavelengths range from one meter to one tenth of a meter (one decimeter).

Secondly, what affects the distance of UHF?

1. Because radio waves in the UHF band propagate almost exclusively by line-of-sight (LOS) and ground reflection. There are almost no reflections from the ionosphere or ground waves. Since the wavelength of UHF waves is comparable to the size of buildings, trees, vehicles, and other common objects, reflection and diffraction from these objects may cause fading due to multipath propagation, especially in built-up urban areas.

2. Since UHF transmissions are limited to 30-40 miles (48-64 km) by the visible horizon and are often limited to shorter distances by local terrain. The clearer the line-of-sight path, the better the range; add obstacles or other obstructions in the line-of-sight path, such as buildings, large trees, hills, mountains, high walls, etc., and the radio waves are blocked, thus greatly reducing the range.

Approximate range for UHF 2 way radios in urban conditions.

1 watt = 1 mile, 200,000 sq. ft., 15 floors

2 watt = 2 miles, 250,000 sq. ft., 20 floors

3 watt = 3 miles, 300,000 sq. ft., 25 floors

4 watt = 4 miles, 350,000 sq. ft., 30 floors

5 watt = 5 miles, 400,000 sq. ft., 35 floors