From mboxrd@z Thu Jan 1 00:00:00 1970 Return-path: Received: from mail2.candelatech.com ([208.74.158.173]:55729 "EHLO mail2.candelatech.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1753189AbbBYSve (ORCPT ); Wed, 25 Feb 2015 13:51:34 -0500 Received: from [192.168.100.236] (unknown [50.251.239.81]) (using TLSv1 with cipher DHE-RSA-CAMELLIA256-SHA (256/256 bits)) (No client certificate requested) by mail2.candelatech.com (Postfix) with ESMTPSA id 536A540A959 for ; Wed, 25 Feb 2015 10:51:34 -0800 (PST) Message-ID: <54EE19B5.9040807@candelatech.com> (sfid-20150225_195138_688914_DE56C6F2) Date: Wed, 25 Feb 2015 10:51:33 -0800 From: Ben Greear MIME-Version: 1.0 To: "linux-wireless@vger.kernel.org" Subject: Question on tx-power and number of chains. Content-Type: text/plain; charset=ISO-8859-1 Sender: linux-wireless-owner@vger.kernel.org List-ID: Suppose a NIC wants to decrease TX power for certain rates based on the number of chains (ie, subtract amount A from requested rate for 2 chains, and B for 3 chains). I assume the NIC wants to do this is because if the pkt is transmitted out each antenna, then there is ~3x the power put onto the air. Now, the question is, should this power-decrease be per rate, and perhaps different for each rate, or can all rates use all tx-chains (and so tx-power should be decreased the same maximum amount based on the hardware's number of chains for each rate). I am thinking that CCK rates can only ever be transmitted by a single chain, so in that case those rates would not need their power decreased from the requested? And if that is so, what about the /a/g/ rates, and lower-speed HT/VHT rates as well? Is there a table somewhere that explains how many chains are used by each rate? Thanks, Ben -- Ben Greear Candela Technologies Inc http://www.candelatech.com