After getting asked a few times how much of a gain a 9dBi or higher WIFI antenna would have over a stock 5dBi that usually comes with most wireless adapters, I decided to give it a try.
First, I ordered a 9dBi antenna to attach to an Alfa AWUS036NH USB adapter. I then used InSSIDer to give me the strength of the signals coming to me. I made a short video of this which is posted below.
I have to say I was not terribly impressed by the signal gain I made. While it did make some difference, it really didn’t boost my signals as much as I would have thought. With the 5DBi antenna, my router signal strength was around -35 to -40. When I plugged in the 9dBi antenna, it was around -30 to -25.
In short, if you order a 9dBi or better antenna than the 5DBi, then you will see better signal strength but don’t expect a huge gain.
This is the antenna I used, you can read more reviews on Amazon here Alfa 9dBi WiFi Booster SMA OMNI-Directional High-Gain Screw-On Swivel Antenna.
Since buying the 9 dBi antenna I have learned more about range and the effective area an antenna can cover. Here is a picture that illustrates how the dBi effects the range of an antenna. As the picture shows a short 2 dBi antenna will have good coverage for devices that are close while the 7 dBi or 9 dBi are better for distance but not close up.