> With roles reversed, you do not necessarily get directional transmitter. I don't get why you put "necessarily". You do not, period. > [...snip...] but the c

> With roles reversed, you do not necessarily get directional transmitter. I don't get why you put "necessarily". You do not, period. > [...snip...] but the claim was "every improvement in sending is completely equivalent in receiving for a system that uses the same antennas for both directions", key word improvement. Yes, the claim is wrong: 1. With the sender at the focus and the receiver farther away, the mirror reduces the loss (due to distance, since everything else is assumed ideal as you already acknowledged) to ZERO. You literally cannot do better than reducing your loss to zero. 2. With the receiver at the focus and the sender farther away, the mirror DOES NOT even remotely reduce the loss due to the distance to zero. Loss is still ~1/r^2. Because the mirror only gets so much of the omnidirectional light. This should be very obvious. I don't care how you slice and dice this, and I'm tired of arguing something this obvious, so I won't keep commenting. 1 is not equal to 1/r^2.