From owner-freebsd-current@FreeBSD.ORG Sun Mar 6 15:38:55 2011 Return-Path: Delivered-To: freebsd-current@freebsd.org Received: from mx1.freebsd.org (mx1.freebsd.org [IPv6:2001:4f8:fff6::34]) by hub.freebsd.org (Postfix) with ESMTP id 1C1F11065678 for ; Sun, 6 Mar 2011 15:38:55 +0000 (UTC) (envelope-from erob@gthcfoundation.org) Received: from relais.videotron.ca (relais.videotron.ca [24.201.245.36]) by mx1.freebsd.org (Postfix) with ESMTP id E82E38FC1B for ; Sun, 6 Mar 2011 15:38:54 +0000 (UTC) MIME-version: 1.0 Received: from [192.168.0.100] ([184.162.50.38]) by vl-mo-mrz23.ip.videotron.ca (Sun Java(tm) System Messaging Server 6.3-8.01 (built Dec 16 2008; 32bit)) with ESMTP id <0LHN00EJZ7G264E0@vl-mo-mrz23.ip.videotron.ca> for freebsd-current@freebsd.org; Sun, 06 Mar 2011 10:38:26 -0500 (EST) Message-id: <4D73AA76.8080009@gthcfoundation.org> Date: Sun, 06 Mar 2011 10:38:30 -0500 From: Etienne Robillard Organization: Green Tea Hackers Club User-Agent: Mozilla/5.0 (X11; U; Linux i686; en-US; rv:1.9.1.16) Gecko/20101227 Icedove/3.0.11 To: abitos@abitos.org X-Enigmail-Version: 1.0.1 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7BIT X-Content-Filtered-By: Mailman/MimeDel 2.1.5 Cc: freebsd-current@freebsd.org Subject: Fwd: Re: can somebody explains OFDM in FreeBSD? X-BeenThere: freebsd-current@freebsd.org X-Mailman-Version: 2.1.5 Precedence: list Reply-To: erob@gthcfoundation.org List-Id: Discussions about the use of FreeBSD-current List-Unsubscribe: , List-Archive: List-Post: List-Help: List-Subscribe: , X-List-Received-Date: Sun, 06 Mar 2011 15:38:55 -0000 my best bet is that VLF/ELF frequencies are using FFT (Fast Fourier Transform) algorithm to increase compression ratio of WLAN devices operating with OFDM-enabled hardware. If that is true then not all WLAN devices can do OFDM thus explaining why you could use 802.11g without it... -------- Original Message -------- Return-Path: X-Original-To: erob@gthcfoundation.org Delivered-To: erob@gthcfoundation.org Received: from mail-fx0-f42.google.com (mail-fx0-f42.google.com [209.85.161.42]) by gthcfoundation.org (Postfix) with ESMTP id 7F93B9C488 for ; Sun, 6 Mar 2011 15:33:37 +0000 (UTC) Received: by fxm20 with SMTP id 20so3451200fxm.29 for ; Sun, 06 Mar 2011 07:33:26 -0800 (PST) Received: by 10.223.106.1 with SMTP id v1mr3580291fao.21.1299425606490; Sun, 06 Mar 2011 07:33:26 -0800 (PST) Received: from [192.168.4.20] (pD9FCB6B4.dip.t-dialin.net [217.252.182.180]) by mx.google.com with ESMTPS id 5sm545591fak.47.2011.03.06.07.33.24 (version=SSLv3 cipher=OTHER); Sun, 06 Mar 2011 07:33:25 -0800 (PST) Message-ID: <4D73A943.90206@abitos.org> Date: Sun, 06 Mar 2011 16:33:23 +0100 From: Tobias Blersch User-Agent: Mozilla/5.0 (Windows; U; Windows NT 5.1; en-US; rv:1.9.2.13) Gecko/20101207 Lightning/1.0b2 Thunderbird/3.1.7 MIME-Version: 1.0 To: erob@gthcfoundation.org Subject: Re: can somebody explains OFDM in FreeBSD? References: <4D7398C6.8030800@gthcfoundation.org> <201103061533.32138.hselasky@c2i.net> <4D73A085.4030009@gthcfoundation.org> <20110306151548.GB29990@night.db.net> <4D73A74A.7040304@gthcfoundation.org> In-Reply-To: <4D73A74A.7040304@gthcfoundation.org> Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 7bit Hi, your post mentioned ELF/VLF radiation, thats electromagnetic waves the frequency range below 30kHz. How should a modulation scheme (OFDM) used in the 2.4/5GHz range be related to radiation in such a low frequency band? Tobias