From owner-stds-802-3-hssg@ieee.org Tue Feb 29 22:22 GMT 2000 Received: from gatekeeper.pdd.3com.com (gatekeeper [161.71.169.3]) by isolan.pdd.3com.com (8.9.1b+Sun/8.9.3) with ESMTP id WAA23025; Tue, 29 Feb 2000 22:22:45 GMT Received: from ruebert.ieee.org ([199.172.136.3]) by gatekeeper.pdd.3com.com (Netscape Messaging Server 3.6) with ESMTP id AAA165A; Tue, 29 Feb 2000 22:21:04 +0000 Received: by ruebert.ieee.org (8.9.3/8.9.3) id QAA01018; Tue, 29 Feb 2000 16:30:22 -0500 (EST) Message-Id: <4.2.0.58.20000229140457.00a7e6e0@192.168.2.12> X-Sender: mwincn@192.168.2.12 X-Mailer: QUALCOMM Windows Eudora Pro Version 4.2.0.58 Date: Tue, 29 Feb 2000 14:30:55 -0700 To: "Edward Chang" , , , From: "Mike Wincn" Subject: RE: PAM-5, what are your BERs ? In-Reply-To: References: <4.2.0.58.20000229064314.00a867e0@mail.bayarea.net> Mime-Version: 1.0 Sender: owner-stds-802-3-hssg@ieee.org Precedence: bulk X-Resent-To: Multiple Recipients X-Listname: stds-802-3-hssg X-Info: [Un]Subscribe requests to majordomo@majordomo.ieee.org X-Moderator-Address: stds-802-3-hssg-approval@majordomo.ieee.org X-Lines: 44 Status: RO Content-Type: text/plain; charset="us-ascii" Content-Length: 1889 Ed: At 02:17 PM 29-02-2000 -0500, Edward Chang wrote: >We are discussing the product developments, which are based on proved >theorems and equations to mathematically calculate all designs. After that, >setting up tests to confirm that the test data, and the analyses are >correlated. Otherwise, repeat the procedures to achieve the goals. >Finally, it will go through extensive system tests and BER tests to certify >a product. > >Engineers do not just "looking at a scope", then make the comment. They >theorize it, quantify it, then make comments. right. that may have been a bad choice of analogy, on my part. i apologize if i have offended anyone. in my read of this thread things seem fairly clear -- i gather, from all of this, that Vivek has a lot of experience in this, perhaps you do too. it's my experience that Vivek's assessment is accurate, as posted. >Unless, some one has extensive communication product development experience >in the past, it is hard for a one to grasp, and appreciate the contents of >the comments put forward on reflectors by those serious contributors. agreed. in any event a more rigorous proof is best delivered in an HSSG meeting. here, we can best highlight one or more concerns. >[...] >The cascading of the frequency response of each component to predict the >over-all system frequency response is a well known basic tool implemented by >all circuit designers. It is as predictable as, 1+1 = 2. well, i suppose so, though i'm not certain i follow your analogy. here, i want to suggest that observation of "a closed eye diagram" may be 'necessary' but isn't always -sufficient- indication of intolerably high BER. i believe there must be additional work. -- J M Wincn, Staff Engineer Cielo Communications, Inc. 325 Interlocken Pkwy, Bldg A Broomfield, CO 80021-3497 Voice: 303-464-2264 Cell: 408-394-5283 Fax: 303-460-6348