alt Hacker News"Antennas are designed to either transmit or receive RF". This isn't even close to realistic. Outside of amplified or active antennas, they have to be bidirectional devices. An active antenna is just a normal passive one with a non-linear junction attached.
Sometimes "to either x or y" doesn't mean "to do one of x or y", sometimes it means "to be able to do both x and y (but not necessarily at the same time purposefully)".