What Range is the Antenna?

19 Apr, 2021, 4:47 AM

Written: September 30, 2018

What Range is the Antenna? Or How many kilometers does your antenna work over?

There is no standard answer to this question. Why let me explain:

From the Antenna (receiving )end of the equation

The technical specification of the antenna offers the only slight clue to the answer. It is measured in gain (How much signal it collects in terms of power  in micro volts, compared generally to a theoretical point antenna called an ISOTROPIC Antenna. It can also be compared to a single standard dipole Antenna made for  specific frequency – so much more power was collected by the antenna as compared to the power collected by the antenna being compared. The Theoretical Isotropic antenna is about 2 dB less than a standard Dipole. ). The only problem is this measurement is not linear – meaning it varies from frequency to frequency received and so is not a standard amount of gain for each channel and so can only be a guide at best.

Personally, I have tended to ignore this specification because an environment in which the antenna is mounted can change the numbers. It is theoretical only and pretty useless in my experience – except as a general guide to the  received pattern (called Polar pattern) or type of antenna to select for a specific area.

Additional Factors that influence range

What size is the transmitter that the antenna is going to be looking at to provide the signal?

To make them easier to relate to their performance, I call them: Baby, Mummy and Daddy bear. There is a massive difference. Baby bear might be 5 Kilometers and Daddy bear might be 100 Kilometers plus. This is a difference the radiated power of the transmitter. If you poor in power to the transmitter say 6000 watts it will travel a long way. If it is 5 watts – as some small transmitters are, it will not travel very far at all. This effect is not related to the receiving antenna but the initial power of the transmitter!

Is the signal travelling in a Horizontal pattern or a Vertical pattern? Again a horizontal signal will travel further.

What type of environment are we lining up our antenna in? Sand or volcanic. BIG BIG difference in result. Volcanic assist signal while sand absorbs it.

So my best guidance is: If you are going to predominantly using it on the East coast where the people live and the transmitting towers

have to cover a bigger area then a non-amplified is worth trying. Worst scenario you add the amplifier later. If however, you intend to get into the middle of this great country then save the frustration and disappointment and go for the “Go Anywhere”  Nomad antenna straight off.






Sally Garden RF Consultant Founder
Wilkgard Technology Group P/L