Richard Harrison wrote:
Art wrote:
"For my interest, what is the unit that must be used for front to back
ratio of a directive antenna?"

I must be an idiot for venturing an answer, but ratios can be just
numbers, but numbers have origins. If radiated power in one direction is
twice that in another (reference), we can say it has a directive gain of
two or we can say it has a 3 dB gain. . .

Forgive me for picking a nit here, but the front/back ratio is the ratio
of radiated *field strength* or radiated *power density*, not radiated
power. Strictly speaking, there is zero power radiated in any single
direction.

Roy Lewallen, W7EL