From glenne@hpsadr2.sr.hp.com Thu Oct 03 10:55:17 1996 Received: from relay.hp.com (relay.hp.com [15.255.152.2]) by tapr.org (8.7.5/8.7.3/1.9) with ESMTP id KAA17835 for ; Thu, 3 Oct 1996 10:55:02 -0500 (CDT) Received: from srmail.sr.hp.com by relay.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA101448000; Thu, 3 Oct 1996 08:53:33 -0700 Received: from hpsadr2.sr.hp.com (n6gn.sr.hp.com) by srmail.sr.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA212297915; Thu, 3 Oct 1996 08:51:56 -0700 Received: by hpsadr2.sr.hp.com (1.37.109.16/15.5+ECS 3.3) id AA093197913; Thu, 3 Oct 1996 08:51:54 -0700 From: Glenn Elmore Message-Id: <199610031551.AA093197913@hpsadr2.sr.hp.com> Subject: Updated pages To: ss@tapr.org Date: Thu, 3 Oct 1996 08:51:53 -0800 (PDT) X-Mailer: ELM [version 2.4 PL21] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit I've added some updates to my Higher Speed Packet Pages including some of the notes I presented at the recent DCC as well as some material on OCARs which I hope may be of interest. There is still more to come as I have time. Glenn Elmore n6gn amateur IP: glenn@SantaRosa.ampr.org Internet: glenne@sr.hp.com |--------------- N6GN's Higher Speed Packet WWW Page -------------------| | | | http://www.tapr.org/~n6gn/index.html | | | |-----------------------------------------------------------------------| From jbloom@arrl.org Thu Oct 03 11:38:47 1996 Received: from mgate.arrl.org (root@mgate.arrl.org [205.217.201.2]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id LAA19617 for ; Thu, 3 Oct 1996 11:38:43 -0500 (CDT) Received: from smtp_gw by mgate.arrl.org with smtp (Smail3.1.29.1 #9) id m0v8qnF-000f5NC; Thu, 3 Oct 96 12:38 EDT Message-Id: Priority: urgent Date: Thu, 3 Oct 1996 13:36:00 -0400 From: "Bloom, Jon, KE3Z" Subject: Useful course? To: "'ss@tapr.org'" X-Mailer: Worldtalk (NetConnex V4.00a)/MIME This appeared on comp.dsp. I thought it might interest some who could manage to attend. (Of course, I realize any dyed-in-the-wool Tucsonite would only attend an ASU course incognito...) ================================================================ * Announcing Two Short Courses in CDMA Communications & DSP * ** December 1996 in Phoenix Arizona ** (1) Fundamentals of Digital Signal Processing December 2-4, 1996 (3 days) Instructor: Prof. Andreas Spanias of Arizona State University Includes: Hands on Experiments on the PC Description of Algorithms and Applications Participants take back to Work Place Software and a complete set of Notes (2) Principles and Applications of CDMA Communications December 5-6, 1996 (2 days) Instructors: Prof. John Sadowsky and Prof. Andreas Spanias of Arizona State University Includes Description of IS-95, IS-96, and IS-127 Standards Participants take back to Work Place a Complete Set of Notes At Grace Inn Hotel Awhatukee, Phoenix, Arizona Coordinator for both courses: Andreas Spanias of Arizona State University **** Group and Early registration Discounts *** If you need a complete brochure Send email to: spanias@asu.edu From RLANIER@mailb.harris.com Thu Oct 03 13:34:20 1996 Received: from sol.corp.Harris.COM (sol.corp.harris.com [137.237.25.4]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id NAA23876 for ; Thu, 3 Oct 1996 13:34:17 -0500 (CDT) Received: from mailb.harris.com by sol.corp.Harris.COM (8.6.12/Kurts Special version 2.0) id OAA04995; Thu, 3 Oct 1996 14:34:10 -0400 Received: from ccMail by mailb.harris.com (IMA Internet Exchange 1.04b) id 25406891; Thu, 3 Oct 96 14:31:37 -0400 Mime-Version: 1.0 Date: Thu, 3 Oct 1996 14:32:20 -0400 Message-ID: <25406891@mailb.harris.com> From: RLANIER@mailb.harris.com (RLANIER) Subject: Spread Spectrum Chip Sets To: ss@tapr.org Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Content-Description: cc:Mail note part I have found a good chip set for DSSS use. Its called the PRISM chip set from Harris Semiconductor. Initially, I thought the price was excessive, but they are now sampling, so experiments could be done at low cost. I am getting a set of these and will let everyone know what I come up with. 73s de Tony, KE4ATO From wb9mjn@wb9mjn.ampr.org Thu Oct 03 14:34:43 1996 Received: from wb9mjn.ampr.org (wb9mjn.ampr.org [44.72.98.19]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id OAA26194 for ; Thu, 3 Oct 1996 14:34:34 -0500 (CDT) From: wb9mjn@wb9mjn.ampr.org Date: Thu, 03 Oct 96 13:28:56 UTC Message-Id: <11109@wb9mjn.ampr.org> To: ss@tapr.org Subject: RE: Updated Pages Hi Glenn, Interesting stuff on ur updated web page. Active Repeaters is a fascinating subject. They can be done with a single an- antenna, and single port amplifiers too. This can lead to a much more economic package, and greatly reduce the RF connectorisation problems discussed in the 10 Ghz Repeater page. IMPATT, and TUNNEL Diodes have been used as negative impedance (single port amps, with Reflection Coeficients > 1) amplifiers. Another way, that is cheap, that gets around the leakage problems, is high speed phase shifters. It would not be an OCAR (On-Channel Repeater) anylonger, but, gain could be very much higher. The recieve direction on the coax is fed into amplifier (for isolation and NF) and then into a 360 degree total phase shift electronically controlled phase shift bank. The phase shift is run up at the Channel BW. This translates the incoming signals in the Channel BW, one channel BW up or down, depending on the direction the phase shifter is run in. Thus, filter isolation can be added to the directivity and/or antenna seperation isolation. Oops, the phase shifting rate is run at the channel BW, not the phase shift. On the subject of antennas for this. Would it not be great to integrate the BW filter into the antenna? As one thing. This can be done with Microstrip antenna technology. This whole area of discussion really gets wild tho. Like, we could have a network, where theusers do not even have radios! With a modulated retrore- flective antenna - amps. As a RF power source scans across each user, his TNC does not transmit, it modulates a phase shifter between a OCAR like antenna at his site, and its single port amp. This causes the reflection to be both at a different frequency, and modulated with his data. Kinda like Aircraft transponders, only a whole bunch cheaper. Hell, since the repeater is so cheap, and the radio so expensive, why not reverse the whole thing? 73, Don. Mailbox : WB9MJN @ N9HSI.IL.USA.NA AMPRNet : wb9mjn@wb9mjn.ampr.org[44.72.98.19] Internet: wb9mjn%wb9mjn.ampr.org@uugate.aim.utah.edu From glenne@hpsadr2.sr.hp.com Thu Oct 03 15:48:33 1996 Received: from hp.com (hp.com [15.255.152.4]) by tapr.org (8.7.5/8.7.3/1.9) with ESMTP id PAA29069 for ; Thu, 3 Oct 1996 15:48:31 -0500 (CDT) Received: from srmail.sr.hp.com by hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA187855704; Thu, 3 Oct 1996 13:48:25 -0700 Received: from hpsadr2.sr.hp.com (n6gn.sr.hp.com) by srmail.sr.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA279115702; Thu, 3 Oct 1996 13:48:24 -0700 Received: by hpsadr2.sr.hp.com (1.37.109.16/15.5+ECS 3.3) id AA281215702; Thu, 3 Oct 1996 13:48:22 -0700 From: Glenn Elmore Message-Id: <199610032048.AA281215702@hpsadr2.sr.hp.com> Subject: Re: [SS:518] RE: Updated Pages To: ss@tapr.org Date: Thu, 3 Oct 1996 13:48:21 -0800 (PDT) In-Reply-To: <11109@wb9mjn.ampr.org> from "ss@tapr.org" at Oct 3, 96 02:35:54 pm X-Mailer: ELM [version 2.4 PL21] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit > Active Repeaters is a fascinating subject. They can be done with a single an- > antenna, and single port amplifiers too. This can lead to a much more economic > package, and greatly reduce the RF connectorisation problems discussed in the > 10 Ghz Repeater page. IMPATT, and TUNNEL Diodes have been used as negative > impedance (single port amps, with Reflection Coeficients > 1) amplifiers. I'm not sure that this is going to be practical at the kind of gains we probably most often like to run. I doubt that much more than 20 dB of directivity isolation can be maintained on a single antenna. > Another way, that is cheap, that gets around the leakage problems, is high Yes, in function, that's basically what satellite transponders do with somewhat different h/w. > This whole area of discussion really gets wild tho. Like, we could have a > network, where theusers do not even have radios! With a modulated retrore- > flective antenna - amps. As a RF power source scans across each user, his It really does get fun to think about the possibilities. Letting a bunch of locals in on the fun by "fixing" the paths among them *really* changes the scene. All of a sudden, everyone is on a hilltop. It has a lot about it that is similar to what has made voice repeaters popular, only with flexibility to play with radios and modes as each user sees fit. In cases where all users "agree" and run the same protocol, letting the repeater poll each of them and letting their hardware get simpler is possible. However, I don't think there is a lot of extra cost involved in making a complete radio, rather than a modulated amplifier, and it leaves the door open for easy upgrades and simultaneous multiple use. I had a slightly alarming thought over lunch today though... What happens when one of these is run at a high level site during a vhf/uhf contest? There might be some extra contacts that shouldn't "count" according to the current rules. 1/2 (:>) Glenn From wb9mjn@wb9mjn.ampr.org Thu Oct 03 18:47:57 1996 Received: from wb9mjn.ampr.org (wb9mjn.ampr.org [44.72.98.19]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id SAA05150 for ; Thu, 3 Oct 1996 18:47:40 -0500 (CDT) From: wb9mjn@wb9mjn.ampr.org Date: Thu, 03 Oct 96 17:56:29 UTC Message-Id: <11118@wb9mjn.ampr.org> To: ss@tapr.org Subject: Re: [SS:519] RE: Updated Pages In-Reply-To: your message of Thu Oct 03 15:54:14 1996 <199610032048.AA281215702@hpsadr2.sr.hp.com> Hi Glenn, This just occured to me. Dewayne has this Start Trek idea. The retro- reflective antenna amp would make a great Star Trek style Lapel pin commun- icator technology, hi. 73, Don. Mailbox : WB9MJN @ N9HSI.IL.USA.NA AMPRNet : wb9mjn@wb9mjn.ampr.org[44.72.98.19] Internet: wb9mjn%wb9mjn.ampr.org@uugate.aim.utah.edu From glenne@hpsadr2.sr.hp.com Fri Oct 04 09:19:37 1996 Received: from hp.com (hp.com [15.255.152.4]) by tapr.org (8.7.5/8.7.3/1.9) with ESMTP id JAA05511 for ; Fri, 4 Oct 1996 09:19:35 -0500 (CDT) Received: from srmail.sr.hp.com by hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA240218772; Fri, 4 Oct 1996 07:19:32 -0700 Received: from hpsadr2.sr.hp.com (n6gn.sr.hp.com) by srmail.sr.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA075918771; Fri, 4 Oct 1996 07:19:31 -0700 Received: by hpsadr2.sr.hp.com (1.37.109.16/15.5+ECS 3.3) id AA051848770; Fri, 4 Oct 1996 07:19:30 -0700 From: Glenn Elmore Message-Id: <199610041419.AA051848770@hpsadr2.sr.hp.com> Subject: Re: [SS:520] RE: Updated Pages To: ss@tapr.org Date: Fri, 4 Oct 1996 07:19:30 -0800 (PDT) In-Reply-To: <11118@wb9mjn.ampr.org> from "ss@tapr.org" at Oct 3, 96 07:06:58 pm X-Mailer: ELM [version 2.4 PL21] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit > > This just occured to me. Dewayne has this Start Trek idea. The retro- > reflective antenna amp would make a great Star Trek style Lapel pin commun- > icator technology, hi. > > Don Sounds great! Maybe we can integrate it with a transporter and finally be able to beam up as well (:>) 73 Glenn From wb9mjn@wb9mjn.ampr.org Fri Oct 04 18:33:34 1996 Received: from wb9mjn.ampr.org (wb9mjn.ampr.org [44.72.98.19]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id SAA23997 for ; Fri, 4 Oct 1996 18:33:14 -0500 (CDT) From: wb9mjn@wb9mjn.ampr.org Date: Fri, 04 Oct 96 16:53:55 UTC Message-Id: <11134@wb9mjn.ampr.org> To: ss@tapr.org Subject: Re: [SS:521] RE: Updated Pages In-Reply-To: your message of Fri Oct 04 09:27:17 1996 <199610041419.AA051848770@hpsadr2.sr.hp.com> Hi Glenn, On a more practical side. The OCAR reduces the resource, at the benefit of cheap connectivity. On one side of a hill, communication can occur inde- pendantly, from the other side of a hill. Thus doubling the resource, until communication is needed between the two sides. With an OCAR, the resource is halfed, all the time. I like ur web page about the REDWOOD paths. Yes, that s the very problem. And the DDMA/WAN idea was a way to have the hardware discover these paths on its own. Its not possible, to fund, in ham radio, site/path survey teams. We need to automate this into the equipment, and then just put more copies of such equipment into the field, and if connectivity doesn t happen, put more copies at problematic places. The REDWOOD situation would never need any hardware modification, or new siting. The path would just get used. And, maybe a few years from now, a nosey operator might try and find out why the equipment is sending the RF 50 miles, to get 3 miles away, hi. OCAR s would be a good idea for the mountain states. Here, u could have 10 MHz worth of bandwidth, in a state wide coverage zone, with only few OCARs, since 1 st fresnel paths are all over, and the OCARs would interconnect the areas isolated from each other. With the sparce population, 10 Mhz should be enuf forever. There is a concern tho. In areas such as the Chicagoland area, where a single site cannot cover the whole area of interest, multiple OCAR s would be needed. Designing and controlling a system of multiple OCAR's, would be quite a chal- lenge, in a small (rf wise) space. If conditions are such that the source station is propagating over a hill, the signal combined with the repeated signal, would probably be useless. There are also aircraft reflections, be- sides tropo-scatter/ducting variability. Is this a technology better suited for 24 Ghz, that is bands where water destroys path, rather than enhances them? The OC (on-channel) aspect of the OCAR just makes this all so problematic. This allows two repeaters to oscillate, if conditions are right. Using a phase shifter based translator, or IRM allows the idea to be generally implemented, without this possibility. But, for multiple repeat systems, it doubles the cost, as two repeaters are needed (on seperate in/out freqs), at each site. Possibly, the CELLNET architecture could be applied. Have 3 input bands, with phase shifter on each, running at different rates, so that all three input bands come out on one output band. Hmm. Its not pretty. How does one do the reverse path, in a area mesh? 73, Don. Mailbox : WB9MJN @ N9HSI.IL.USA.NA AMPRNet : wb9mjn@wb9mjn.ampr.org[44.72.98.19] Internet: wb9mjn%wb9mjn.ampr.org@uugate.aim.utah.edu From bad@uhf.wdc.net Sun Oct 06 17:07:38 1996 Received: from uhf.wdc.net (uhf.wdc.net [198.147.74.44]) by tapr.org (8.7.5/8.7.3/1.9) with ESMTP id RAA23083 for ; Sun, 6 Oct 1996 17:07:34 -0500 (CDT) Received: (from bad@localhost) by uhf.wdc.net (8.7.5/8.6.12) id SAA07418; Sun, 6 Oct 1996 18:09:56 -0400 (EDT) Date: Sun, 6 Oct 1996 18:09:56 -0400 (EDT) From: Bernie Doehner To: ss@tapr.org Subject: DES chip for Wavelan cards. Message-ID: MIME-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII Hi: Does anyone have a NCR Wavelan card with DES installed chip? We are developing a Wavelan driver for FreeBSD and I would like to test the DES code in our driver. I hope that NCR used a standard part that I can buy from one of the companies that makes DES chips. (This is for the first generation full-height Wavelan cards, where the RF deck is an integral part of the card (and not on a daughterboard). Also: If someone is interested in being a beta tester, let me know. Bernie nu1s From sia@nest.org Sun Oct 06 21:39:10 1996 Received: from seagull.nest.org (nest-breezy.breezy.jriver.com [207.111.142.40]) by tapr.org (8.7.5/8.7.3/1.9) with ESMTP id VAA02782 for ; Sun, 6 Oct 1996 21:39:06 -0500 (CDT) Received: (from sia@localhost) by seagull.nest.org (8.7.5/8.6.12) id VAA20150 for ss@tapr.org; Sun, 6 Oct 1996 21:39:02 -0500 (CDT) Message-Id: <199610070239.VAA20150@seagull.nest.org> Subject: Re: [SS:523] DES chip for Wavelan cards. To: ss@tapr.org Date: Sun, 6 Oct 1996 21:39:02 -0500 (CDT) In-Reply-To: from Bernie Doehner at "Oct 6, 96 05:17:38 pm" From: Igor Sviridov Reply-To: sia@nest.org Return-Receipt-To: sia@nest.org Precedence: airmail X-Class: Fast X-NIC-Handle: IS39 X-Work-Email: sia@jriver.net X-Work-Phone: +1 612 3392521 x214 X-Work-Fax: +1 612 3394445 X-Work-Snail: 125 1st North Street, Minneapolis, MN, 55401 X-Home-Email: sia@nest.org X-Home-Phone: +1 612 4042553 X-Home-Snail: 18100 Breezy Point Rd, Wayzata, MN, 55391-2715 X-Pager-Phone: +1 888 8453192 X-Pager-Email: sia@interpage.net X-Mailer: ELM [version 2.4ME+ PL11 (25)] MIME-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Quoting Bernie Doehner letter: > Hi: > > Does anyone have a NCR Wavelan card with DES installed chip? > > We are developing a Wavelan driver for FreeBSD and I would like to test > the DES code in our driver. I hope that NCR used a standard part that > I can buy from one of the companies that makes DES chips. [ sorry, this is not about DES chip ] I'm using right now Wavelan under FreeBSD with driver by Jim Binkley : > > Date: Mon, 05 Aug 1996 17:38:21 -0700 > From: Jim Binkley > To: freebsd-mobile@FreeBSD.ORG > Sender: owner-mobile@FreeBSD.ORG > Subject: mobile-ip alpha release for freebsd2.1R and wavelan update > > > Greetings, > > We have put release of our alpha Mobile-IP code out at > > ftp://zymurgy.cs.pdx.edu/pub/mobility/mip.tar.gz > > along with a re-release of the wavelan drivers. > > The Mobile-IP release was done on FreeBSD 2.1R and > includes kernel changes necessary for mobile-ip. We provide > src and binaries for the routing daemons and utilities used with them. > The Mobile-IP release is based on draft 15 which is included. We will > be working on updating it to draft 17 over the summer. > > We based our release to some extent on ATT WaveLAN radio cards > and the drivers plus some new config utilities are present in the code. > (However our Mobile-IP should work with ethernet as well). > The wavelan code is both IN mip.tar.gz and in a separate wavelan.tar.gz > file. Drivers are included for the ISA wavelan card and for the PCMCIA > card. There are some mods to the drivers that people may not have > as there are some ioctls and other instrumentation that did not previously > exist. Note: a possible patch by Matt Thomas for the wlp0 pcmcia driver and > a major remunge by Jon Inouye for the 2.2SNAP/pcmcia socket support > is not in there yet. There are two little utilities supplied that > may be of interest. One can get/set the NWID at runtime (both wl and wlp). > The other can read out signal strength and other related parameters > (only wlp). The drivers supplied are compatible with 2.1R. > > Any communication on the subject should be sent to: > > mobileip@zymurgy.cs.pdx.edu > > The code can also be accessed on the web via: > > http://www.cs.pdx.edu/research/SMN > > regards, > > Jim Binkley > jrb@cs.pdx.edu > -- igor From glenne@hpsadr2.sr.hp.com Mon Oct 07 10:34:52 1996 Received: from hp.com (hp.com [15.255.152.4]) by tapr.org (8.7.5/8.7.3/1.9) with ESMTP id KAA02039 for ; Mon, 7 Oct 1996 10:33:34 -0500 (CDT) Received: from srmail.sr.hp.com by hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA046732411; Mon, 7 Oct 1996 08:33:32 -0700 Received: from hpsadr2.sr.hp.com (n6gn.sr.hp.com) by srmail.sr.hp.com with ESMTP (1.37.109.16/15.5+ECS 3.3) id AA216612410; Mon, 7 Oct 1996 08:33:31 -0700 Received: by hpsadr2.sr.hp.com (1.37.109.16/15.5+ECS 3.3) id AA081252409; Mon, 7 Oct 1996 08:33:29 -0700 From: Glenn Elmore Message-Id: <199610071533.AA081252409@hpsadr2.sr.hp.com> Subject: Re: [SS:522] RE: Updated Pages To: ss@tapr.org Date: Mon, 7 Oct 1996 08:33:29 -0800 (PDT) In-Reply-To: <11134@wb9mjn.ampr.org> from "ss@tapr.org" at Oct 4, 96 06:49:04 pm X-Mailer: ELM [version 2.4 PL21] Mime-Version: 1.0 Content-Type: text/plain; charset=US-ASCII Content-Transfer-Encoding: 7bit Don writes: > On a more practical side. The OCAR reduces the resource, at the benefit of > cheap connectivity. On one side of a hill, communication can occur inde- > pendantly, from the other side of a hill. Thus doubling the resource, until > communication is needed between the two sides. With an OCAR, the resource is > halfed, all the time. Well, the problem of getting lots of bandwidth to a lot of users has a variety of constraints it can bounce off. It might be a little like the dual problems 1) I have no money. 2)I have so much money I don't have a place to put it. If we had perfect paths on a totally flat earth we might find that every information transaction could be a single hop but that we had to coordinate like crazy to share the resource to do it. If we had a very lossy set of terrain/paths with a curved earth (and we generally do) we can get only a very small number of links but don't need much spectral coordination. However, all other things equal, I'll take the first scenario because the waste is (or could be) a great deal less; at least up to the point that it is no longer possible to get the necessary cooperation/coordination. This means that total system cost is lower. Within amateur radio today, I'm a little afraid to look to see where the the link-limited/coordination-limited boundary occurs. Maybe it really is with each ham not being able to work anyone else. I hope it is a bit higher than that though. Put another way, while the per-user portion of the total resource might be halved with an OCAR, the total information efficiency can be a million times better (*if* we can cooperate). I'll take the 3 dB penalty in that situation. In fact, I'd love it if we had that problem. At the moment I don't know of many highspeed, wideband amateur systems which are suffering from the problem you suggest. ATV repeaters are about the only thing I can think of that seem likely. Even that sort of problem could probably be solved easily with antenna directivity and path/site selection *if* those involved would cooperate. > I like ur web page about the REDWOOD paths. Yes, that s the very problem. And > the DDMA/WAN idea was a way to have the hardware discover these paths on its > own. Its not possible, to fund, in ham radio, site/path survey teams. We need > to automate this into the equipment, and then just put more copies of such > equipment into the field, and if connectivity doesn t happen, put more copies > at problematic places. The REDWOOD situation would never need any hardware > modification, or new siting. The path would just get used. And, maybe a few > years from now, a nosey operator might try and find out why the equipment is > sending the RF 50 miles, to get 3 miles away, hi. I'm not sure that any mortal is up to making a totally self-configuring system that can solve amateur radio's coordination problems for it, unless it is one which simply eliminates the hobby. It's for this reason that I suggested in one of the CNC papers that I thought cooperation and coordination a bigger issue (if/when we ever get to the point of having that problem with high speed systems) than the technical one. If the user base and resource contention increased enough, I'd expect someone other than a nosey operator to notice it sooner. > OCAR s would be a good idea for the mountain states. Here, u could have 10 > MHz worth of bandwidth, in a state wide coverage zone, with only few OCARs, > since 1 st fresnel paths are all over, and the OCARs would interconnect the > areas isolated from each other. With the sparce population, 10 Mhz should be > enuf forever. I like the idea of OCARs for a social reason as well. It has the same flavor to it as nbfm repeaters; that is, a small group of locals (unfortunately its usually one or two individuals doing all the work) cooperating to put the right hardware in place for each other in the locale that lets there otherwise-unusable HT do something interesting (to them, anyway). It requires local adaptation to local problems. It's a small-government model, I suppose. > There is a concern tho. In areas such as the Chicagoland area, where a single > site cannot cover the whole area of interest, multiple OCAR s would be needed. > Designing and controlling a system of multiple OCAR's, would be quite a chal- > lenge, in a small (rf wise) space. If conditions are such that the source > station is propagating over a hill, the signal combined with the repeated > signal, would probably be useless. There are also aircraft reflections, be- > sides tropo-scatter/ducting variability. Is this a technology better suited > for 24 Ghz, that is bands where water destroys path, rather than enhances them? I need to add some detail about the preferential layout for OCARs to minimize the multipath-contaminated area you mention. Ideally, the OCAR uses a directional antenna and is located at the outskirts of the mass of users, not in between them. If there is already suitable propagation over the hill, there should probably not be an OCAR there. The terrain limited regions are generally smaller at higher frequencies (where therer's also more bandwidth). I don't think we should normally be putting OCARs up on 2M nor probably even on 450 MHz. OCARs are not a panacea, but I think they do offer a useful flexibility for certain situations and might serve to further the hobby in general. > The OC (on-channel) aspect of the OCAR just makes this all so problematic. > This allows two repeaters to oscillate, if conditions are right. Using a phase > shifter based translator, or IRM allows the idea to be generally implemented, > without this possibility. But, for multiple repeat systems, it doubles the > cost, as two repeaters are needed (on seperate in/out freqs), at each site. Avoiding oscillation of two is just a case of the requirement of achieving adequate antenna isolation for the 2nd one. This needs to be addressed for each installation. OCARs, like any other wider area resource must be coordinated. They don't self-configure. Hams have to get along if we're going to share our resources. This is the root problem. > Possibly, the CELLNET architecture could be applied. Have 3 input bands, > with phase shifter on each, running at different rates, so that all three input > bands come out on one output band. Hmm. Its not pretty. How does one do the > reverse path, in a area mesh? I don't think I'd want to try. The goal of the OCAR is to get an area large enough to contain a critical mass of users to be able to communicate with low incremental path loss so that higher capacity information systems can function. We aren't trying to "flatten" the entire earth. We still want to trunk multiple regions together with point-point hardware. If/When the user density gets big enough that per-user performance is impacted the area should be subdivided; the first OCAR should be eliminated and "the right thing" should be done among each of the resulting groups to keep communciations efficiency high enough. This probably means adding another level of hierarchy. I'll try and get some more hardware and result information about our OCAR experiene here up on the web pages before too long. Thanks for your thoughts and comments. Glenn From wb9mjn@wb9mjn.ampr.org Mon Oct 07 15:52:57 1996 Received: from wb9mjn.ampr.org (wb9mjn.ampr.org [44.72.98.19]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id PAA20228 for ; Mon, 7 Oct 1996 15:52:37 -0500 (CDT) From: wb9mjn@wb9mjn.ampr.org Date: Mon, 07 Oct 96 14:33:37 UTC Message-Id: <11156@wb9mjn.ampr.org> To: ss@tapr.org Subject: Re: [SS:525] RE: Updated Pages In-Reply-To: your message of Mon Oct 07 10:56:02 1996 <199610071533.AA081252409@hpsadr2.sr.hp.com> Hi Glenn, The scenerio 1 result is that you cannot communicate with any other hams. Without Money (time being an equivalent), there is no way to make a system. Scenrio 2, is the situation that the local packet club was in for many years, to the point that it has lost allot of its vitality. Without coordination, , even those with sufficient funds cannot communicate as required by the application. The result with the local club, is that Scernerio 2 has led to Scenerio 1. Well, YES, ATV is the model of the next generation Packet Radio systems. If we bull ahead, without forethought, we will fall into the same trap. And, so like u say, we need directivity to solve it. But, also, we have to avoid the coordination problem. Because nobody in Ham Radio is going to pay anyone of us to be professional site surveyors and coordinators. Indeed, anybody who tries to do that job will be driven out of ham radio, by the mob. DDMA/WAN gets around this situation, by making the coordination dynamic, and as requir- ed. With DDMA/WAN, the cooperation is in using the equipment, not in argueing with a Coordination Organisation for several years. I can appretiate the idea to use a historically succesful paradigm as a model for future social adoption of new technology. But the fact that a small group comraderie results in a such a major resource monopolisation, reminds me of the very problems of the old paradigm. But, I think your group may have solved the ATV problem. At 10 Ghz, the stuff is cheap enuf, and the bandwidth available enuf, that the traditionally small group of ATV ers can really have a ball, without being glutunous. Yet, still being very inexpensive, and with good range. MPEG'ers, FMTV'ers and NTSC hold- outs can all use the same thing, and contribute to it, without using up a whole band. This multiplies effectiveness, rather than dispersing it. As is the situation now, with TV on 440/900/1.2 Ghz. 73, Don. Mailbox : WB9MJN @ N9HSI.IL.USA.NA AMPRNet : wb9mjn@wb9mjn.ampr.org[44.72.98.19] Internet: wb9mjn%wb9mjn.ampr.org@uugate.aim.utah.edu From rwhiting@winternet.com Wed Oct 09 19:04:46 1996 Received: from icicle.winternet.com (adm@icicle.winternet.com [198.174.169.5]) by tapr.org (8.7.5/8.7.3/1.9) with ESMTP id TAA24390 for ; Wed, 9 Oct 1996 19:04:38 -0500 (CDT) Received: (from adm@localhost) by icicle.winternet.com (8.7.5/8.7.5) id TAA16990; Wed, 9 Oct 1996 19:04:30 -0500 (CDT) Date: Wed, 9 Oct 1996 19:04:30 -0500 (CDT) Posted-Date: Wed, 9 Oct 1996 19:04:30 -0500 (CDT) Message-Id: <199610100004.TAA16990@icicle.winternet.com> Received: from ppp-67-110.dialup.winternet.com(204.246.67.110) by icicle.winternet.com via smap (V2.0a1) id xma016896; Wed, 9 Oct 96 19:04:01 -0500 X-Sender: rwhiting@mail.winternet.com X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: ham-digital@ucsd.edu, ss@tapr.org From: Rick Whiting Subject: Video From Field to Classroom I'm posting the following message from the EDTECH mail list in the hope that someone here might be able to suggest a suitable wireless technology for the air link, e.g., one of the Part 15 spread spectrum products. Date: Tue, 8 Oct 1996 08:44:51 EDT From: Rob Ross Subject: Possibility to send real-time video from field to classroom? I have been searching the literature for a way to broadcast nature into the classroom, but the closest I've come is teleconferencing from a laboratory setting. I would greatly appreciate any advice anyone may have on this. [I apologize for any cross-postings you may have received.] A bit more explanation: I am looking for a way to send a video signal from a remote location -- i.e., outdoor settings (e.g., forests, beaches, anyplace...) -- to a classroom. One teacher would go into the field with a camera, and communicate with (and be directed by) another teacher and students in a class. The purpose would be to get students in contact with the field on a very regular basis when field trips are unfeasible -- and enable the advantages of interaction within a classroom. The video would only need to go one way of course; the teacher in the field need only receive audio. My needs sound like those of a news broadcast, with an anchor and someone reporting from location. But I imagine that the technology, such as satallite links, would be unavailable for individual classes. I wonder if it is possible to send a good video signalfrom a remote location that could be picked up by modern videoconferencing technology. A couple of suggestions I have had (but that hadn't actually tested): (1) taking a wireless modem and laptop computer with internet videoconfercing software into the field, so long as receivers/transmitters are not too far away, or (2) using a cellular telephone, cellular modem, and laptop with phone-based videoconfercing software. I also found a company called KaStar that intends to use a "Ka band satellite transmission system" for low cost, on demand, interactive videoconfercing, etc. This would work, but it'll be several years before it's in operation, and I wonder how low cost it'll really be. I would be very grateful if anyone any advice about or experience with this sort of system. Thanks. Sincerely, Rob Ross ------------------------------------------------------------------------ Richard A. (Rick) Whiting Home Phone: + 1 612 550 1213 RF Engineer, AirTouch Cellular Work Phone: + 1 612 595 5065 5780 Rosewood Ln. N. E-mail: rwhiting@winternet.com Plymouth, MN 55442-1411 Packet: W0TN @ WB0GDB.MN.USA.NOAM ------------------------------------------------------------------------ From bruce@satscan.com Thu Oct 10 07:14:44 1996 Received: from satscan.com (root@satscan.com [205.199.65.1]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id HAA21759 for ; Thu, 10 Oct 1996 07:14:34 -0500 (CDT) From: bruce@satscan.com Received: from 205.199.65.1 (boris.satscan.com [205.199.65.4]) by satscan.com (8.6.9/8.6.9) with SMTP id FAA02524 for ; Thu, 10 Oct 1996 05:18:17 -0700 Date: Thu, 10 Oct 1996 05:18:17 -0700 Message-Id: <199610101218.FAA02524@satscan.com> X-Sender: bruce@satscan.com X-Mailer: Windows Eudora Version 1.4.3 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: ss@tapr.org Subject: Re: [SS:527] Video From Field to Classroom >I'm posting the following message from the EDTECH mail list in the hope that >someone here might be able to suggest a suitable wireless technology for the >air link, e.g., one of the Part 15 spread spectrum products. Why spread spectrum? Why not plain ol' ATV? If you can find a local Ham club that has an active ATV group they may be able to provide the means for this. There are many clubs that would be willing to help and would appreciate the public exposure. I think you will find that SS for this application may be a bit expensive given the budget restraints that are imposed on the public school systems. Bruce KF7PJ > >Date: Tue, 8 Oct 1996 08:44:51 EDT >From: Rob Ross >Subject: Possibility to send real-time video from field to classroom? > >I have been searching the literature for a way to broadcast nature into the >classroom, but the closest I've come is teleconferencing from a laboratory >setting. I would greatly appreciate any advice anyone may have on this. >[I apologize for any cross-postings you may have received.] > >A bit more explanation: >I am looking for a way to send a video signal from a remote location -- >i.e., outdoor settings (e.g., forests, beaches, anyplace...) -- to a >classroom. One teacher would go into the field with a camera, and >communicate with (and be directed by) another teacher and students in a >class. The purpose would be to get students in contact with the field on >a very regular basis when field trips are unfeasible -- and enable the >advantages of interaction within a classroom. > >The video would only need to go one way of course; the teacher in the field >need only receive audio. My needs sound like those of a news broadcast, >with an anchor and someone reporting from location. But I imagine that the >technology, such as satallite links, would be unavailable for individual >classes. > >I wonder if it is possible to send a good video signalfrom a remote >location that could be picked up by modern videoconferencing technology. A >couple of suggestions I have had (but that hadn't actually tested): (1) >taking a wireless modem and laptop computer with internet videoconfercing >software into the field, so long as receivers/transmitters are not too far >away, or (2) using a cellular telephone, cellular modem, and laptop with >phone-based videoconfercing software. I also found a company called KaStar >that intends to use a "Ka band satellite transmission system" for low cost, >on demand, interactive videoconfercing, etc. This would work, but it'll be >several years before it's in operation, and I wonder how low cost it'll >really be. > >I would be very grateful if anyone any advice about or experience with this >sort of system. > >Thanks. > >Sincerely, >Rob Ross > ------------------------------------------------------------------------ > Richard A. (Rick) Whiting Home Phone: + 1 612 550 1213 > RF Engineer, AirTouch Cellular Work Phone: + 1 612 595 5065 > 5780 Rosewood Ln. N. E-mail: rwhiting@winternet.com > Plymouth, MN 55442-1411 Packet: W0TN @ WB0GDB.MN.USA.NOAM > ------------------------------------------------------------------------ > > Bruce Weber, KF7PJ, Satscan Corporation / Cascade Technology PO Box 1109, Sultan WA 98294-1109 (360)-793-3433 FAX: 793-0359 From ssampson@othello.tinker.af.mil Thu Oct 10 08:34:45 1996 Received: from othello.tinker.af.mil (othello.tinker.af.mil [137.240.38.189]) by tapr.org (8.7.5/8.7.3/1.9) with SMTP id IAA25160 for ; Thu, 10 Oct 1996 08:34:40 -0500 (CDT) Received: from localhost by othello.tinker.af.mil (AIX 4.1/UCB 5.64/4.03) id AA13290; Thu, 10 Oct 1996 08:34:09 -0500 Sender: ssampson@othello.tinker.af.mil Message-Id: <325CFB50.167E@othello.tinker.af.mil> Date: Thu, 10 Oct 1996 08:34:08 -0500 From: "Steven R. Sampson" Organization: TRW Space & Electronics Group X-Mailer: Mozilla 3.0b6Gold (X11; I; AIX 1) Mime-Version: 1.0 To: ss@tapr.org Subject: Re: [SS:528] Re: Video From Field to Classroom References: <199610101218.FAA02524@satscan.com> Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit bruce@satscan.com wrote: > > >I'm posting the following message from the EDTECH mail list in the hope that > >someone here might be able to suggest a suitable wireless technology for the > >air link, e.g., one of the Part 15 spread spectrum products. > > Why spread spectrum? Why not plain ol' ATV? If you can find a local Ham club > that has an active ATV group they may be able to provide the means for this. > > Bruce KF7PJ The phrase "If you can find a local Ham club that has an active ATV group.." is probably the killer requirement. On the other hand, most Part-15 devices are made for digital, not video. That is, they like to see digitized voice or data, with maybe an audio jack. The video devices, such as the "Rabbit" type are very short range. They probably do want to use Ham radio ATV devices, as they are easily put together with additional Amps and Beams as needed. Plug and Play... Steve