I'd love to be able to tell you that you can do that and everything would be OK. However, it's frequently just not that simple.
You see, adding passive gain (more dB at the antenna) means they have to get that gain from somewhere ... that "somewhere" is the shape of the signal.
When you get more gain from (what appears to be) an omni-directional (360 degrees lateral) antenna, the only place to redirect that exta energy from is the top and bottom of the radiated (former) sphere.
That means for some angle vertically, there is a shadow. Higher gain antennas tend to be sky shooters ... i.e., the pattern is not completely lateral (like a lighthouse).
You need to look at (understand, compare ...) the pattern and how it will fit your environment. That should be coupled and verified with a follow-up site survey to ensure the coverage is what you expected.
It is possible that your issue is noise/interference ... beefing up the gain on the antenna has as much chance of breaking ot more as it does fixing it.
Or it could be as simple as just moving the antenna a few inches (or a few feet, or a few meters).
There's no way to blind guess this; you need to at least light up Netstumbler (www.netstumbler.com it's free) and then verify your signal strengths and noise characteristics in your work areas.
Transferring Crash file from standby:
Login to the Active WLC in HA.
(Cisco Controller) >transfer upload datatype crash
(Cisco Controller) >transfer upload filename <Desired filename>
(Cisco Controller) >transfer up...
This is the start of a display filter cross reference between Wireshark and OmniPeek.
The 1st installment is a table of advanced filters. More filters will be added as time allows.
It is a living doc, so check back for changes every so often
Please feel ...
I have created a Powershell script to automatically add a Wireless Guest User on Cisco WLCs. (tested on 2500 Series)
The script should be completely self explanatory.
Powershell SNMP Module (Install-Module -Name SNMP)
SNMP Write Access to...