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technix / ham_radio

Minetest mod: radio transmitters, beacons, and receivers
MIT License
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transmission range formula #3

Closed severak closed 2 years ago

severak commented 2 years ago

I don't understand how power of transmitter is calculated ( in ham_radio:locate_transmitter). The formula is unfamiliar to me and I was able to to receive signal from transmitter more than 30000 blocks away from me.

I understand that in real life HAMs are able to pick signals from very long distance but from game perspective I found it little bit boring.

Can you please explain how this formula works?

technix commented 2 years ago

Sure! This formula is a polynomial I created with online polynomial generator. Don't remember which one I used, but, for example, this one can do the job: https://arachnoid.com/polysolve/ I provided desired values for specific points, and generator created a function which gives you smooth graph based on these - so signal power decreases gradually.

Here you can see the graph and how I tried other, simpler, approaches: https://docs.google.com/spreadsheets/d/1VoQ8IVrwOxH_Dvu4HLN2nckRAF0XXeNP755SNWmYxrc/edit?usp=sharing

So if you want to limit signal distance, you may generate another polynomial which gives you the signal fade curve you need.

technix commented 2 years ago

Also, this formula affects only signal strength displayed when using handheld receiver. You still able to receive RDS messages from any transmitter no matter how far it is.