You should watch this
AB316: Apply Radio Frequency (RF) Fundamentals to Optimize Wi-Fi Design - YouTubeIt's all about the specifics of the space you are trying to cover. If you have obstructions, then those directional antennas are going to send the signal further away, but if you can mount an AP in the middle of a clear flat area, then the circular antenna is going to get you a lot totalcoverage.
We've got athletic fields which are flat with no trees or buildings, and an existing light pole smack dab in the middle. The x75 antenna pattern is well suited. For a campus quad that's ~75m x ~275m, the x77 antenna pattern is the way to go.
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Cathy Fasano
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