We came across an old blog post by Michael Martens, which contains an excellent explanation of what it means when people talk about Antenna Gain / Dbi.
Since it also clarifies the reason for antennas in the two way radio world, we HAD TO share.
“I’m gonna take a confusing subject and hopefully demystify it. Antenna Gain is a popular subject amongst hams. We talk about gain all the time, we’ll compare antenna systems and apply values to as how impressive they are by their gain figures. But what exactly is antenna gain, and what do those numbers mean to…”
Source: Antenna Gain Explained