Marconi's law

Marconi's law is the relation between height of antennas and maximum signaling distance of radio transmissions. Guglielmo Marconi enunciated at one time an empirical law that, for simple vertical sending and receiving antennas of equal height, the maximum working telegraphic distance varied as the square of the height of the antenna. It has been stated that the rule was tested in experiments made on Salisbury Plain in 1897, and also by experiments made by Italian naval officers on behalf of the Royal Italian Navy in 1900 and 1901. Captain Quintino Bonomo gave a report of these experiments in an official report.

If H is the height of the antenna and D the maximum signalling distance in meters, then we have, according to Marconi's law

where c is some constant.

Marconi's law can be deduced theoretically as follows:

The above law is, however, much interfered with by the nature of the surface over which the propagation takes place.