Ubiquiti 802.1a 400mW card received - Working with wpa_supplicant/hostapd 0.4.3

[Beat Meier]

Hello

I've just received my first 4 Ubiquiti 802.11a 400mW cards.
Installed in wrap and they work with hostapd, wpa_supplicant-0.4.3 and 
madwifi-bsd-20050702.

The  link quality is 59/94, signale level -32 and noise -95, snr +63
My NL- 5354MP+ Aries2 had link quality is 65/94, signale level -30 and 
noise -95, snr +65
The distance of client/server is about 5m. Client has a 22dbi Grid 
antenna and the server
a 3db ruber duck.

With linksys WPC54G and ndiswrapper to linksysWRT54G I have
 link quality is 100/100, signale level -25 and noise -256, snr +226
Is the noise level bad by ndsiwrapper or madwifi?
What is wrong?

I read a lot of settting power with atheros but still don't know how to 
set ...
I use madwifi-bsd-20050702 driver with hostap/wpa_supplicantp.0.4.3.

I noticed also that if I use iperf the frequency of the client is changing.

Does anybody have already infos about useing this card?
How to set transmit power etc.
How can I send with 400mW power?

Why do I not reach better link quality?

Thanks for any info.

Greetings

Beat