near-field distance attenuation follows an inverse cube law (1/d^3), while in the far-field it follows inverse law (1/d). Prove mathematically how we arrive at 60dB/decade from the inverse distance cube relation and 20dB/decade from the inverse distance
20 log (D) where D is the distance
The Attempt at a Solution
I'm pretty sure this problem is similar to control theory in converting magnitude to DB scale with 20 log (D). I can actually see the answer just by doing that; however, I'm thinking I'm missing the big picture somewhere by doing that. Mostly I can't seem to justify using the above equation.