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Wireless Troubleshooting Questions

We have a Cisco 4400 WLC with about 70 Cisco AIR-1131AG-A-K9 access points.  The controller runs and the access points run code. 

We work in a hospital enviroment and nurses from one of our floors (3N) are complaining about poor/low signal when they enter a patient room with a mobile/nursing cart.  They say that the low signal strength really slows them/their medical applications (Meditech POM) and they are forced to move to a computer with an Ethernet connection to work.  They are then forced to basically communicate with the patient by yelling or move back in forth between the wired computer and the patient room.  The mobile/nursing carts are just specialized mobile workstations with a dell laptop and a battery backup. 

The native Windows XP wireless management bit says that in one particular problem area we get about two bars and are connected at 11 mpbs.  I can set my dell laptop ontop of the mobile cart and while I more-or-less get the same signal strength my connection speed is faster.  We found that we were both connected to the same AP, but the slower device connected over the 802.11g and the faster device connected over 802.11a.

I also know that each 802.11a radio only had between 1-3 clients associated with them, while our 802.11g radios each had between 3-8 clients associated with them.  We do not allow 802.11b, so I am not sure how to explain the difference in speed.  My guess is that it is due to the number of clients associated with the 802.11a radio vs the 802.11g radio, or am I am totally off?

I think our biggest problem is the low signal strength in the patient rooms.  I unfortnately, did not document the RSSI in that room or even conduct any type of performance tests.  I think we spent too much time trying to blame the issue on some type of interference or rouge AP, but that didn't return anything.  We did have two of the three access points show that they failed the interference profile, but that seemed to have been transient.  What types of things should I do to determine if the signal strength is at fault or it is just the scape goat, futher more the only means of addressing the poort/low signal that I know of is by increasing the power level on the access points.  they are currently set to 1.  How much would you increase the signal to begin with?

I added a AP placement map.  I indicated the location from which we tested with a blue dot.  Please let me know if I need to add or clarify anything.  Thank you all for any assistance or suggestions you can offer.

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Re: Wireless Troubleshooting Questions

Is TPC turned on?
Are the wireless Drivers to the COW updated?

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