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Date: Thu, 26 Jun 2008 17:12:57 +0200
From: Petar Bogdanovic <petar@smokva.net>
To: freebsd-net@freebsd.org
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Subject: ath hostap: antenna diversity or not?
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Hi,

in order to compare the performance between antenna-diversity on and off
I did a quick test with the following sysctl settings:

	# antenna-diversity on
	dev.ath.0.diversity=1

	# antenna-diversity off
	dev.ath.0.diversity=0
	dev.ath.0.txantenna=1
	dev.ath.0.rxantenna=2


The performance was pretty much the same but I noticed that the
link-quality reported by my laptop was notable lower with enabled
antenna-diversity (AD):

	~ 43/70 (AD on)
	~ 51/70 (AD off)


I've read a few things about AD on Wikipedia and it seems to be a good
technique to achieve a better signal quality but OTOH there are people
who recommend turning it off to get a better signal quality.

So whats actually true here?


Thanks,

Petar