At my campground, my antenna (9dbi) is connected to my router. I am at least 300 feet from the A.P. And here are the readings I get: 2.45download/1.09upload. My router reads --48dbm. Would i get an even better signal with à yagi antenna (16dbi) than I got right now or would I waste money? Thanks!
Would you get better signal? Maybe. Many times any additional antenna gain is offset by loss in coax. There is not standardized testing for these aftermarket antennas, so that 16dB gain is unknown if it real or not. A yagi is directional, which could help your transmit.