From wd5ivd@tapr.org Fri Dec 01 00:36:51 1995 Received: (from wd5ivd@localhost) by sys1.tapr.org (8.7.2/8.7.2) id AAA10376; Fri, 1 Dec 1995 00:36:51 -0600 (CST) From: Greg Jones Message-Id: <199512010636.AAA10376@sys1.tapr.org> Subject: New Page on the www.tapr.org/ss To: ss@tapr.org, tapr-bb@tapr.org (TAPR-BB mailing) Date: Fri, 1 Dec 1995 00:36:50 -0600 (CST) X-Mailer: ELM [version 2.4 PL24] Content-Type: text Darryl Smith, VK2TDS, has allowed us to put his Thesis Page on "A Spread Spectrum Packet Radio Network" on our the Amateur Spread Spectrum Web Page. The report was submitted in partial fulfilment of the requirements for the degree of bachelor of engineering (UTS) in Electrical Engineering. Academic Supervisor: A/Prof. Sam Reisenfeld. UNIVERSITY OF TECHNOLOGY SYDNEY, SCHOOL OF ELECTRICAL ENGINEERING http://www.tapr.org/ss The HTML page is a little large and we might have a split up page version later when there is some time. Lots of good information and a whole new set of references in the document. Cheers - Greg, WD5IVD From dewayne@warpspeed.com Fri Dec 01 12:10:46 1995 Received: from warpspeed.com (WA8DZP@odo.warpspeed.com [204.118.182.20]) by sys1.tapr.org (8.7.2/8.7.2) with ESMTP id MAA04473 for ; Fri, 1 Dec 1995 12:10:36 -0600 (CST) Received: from [204.118.182.22] by warpspeed.com with SMTP (Apple Internet Mail Server 1.0); Fri, 1 Dec 1995 10:10:33 -0800 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Fri, 1 Dec 1995 10:10:22 -0800 To: dewayne-net@warpspeed.com (Dewayne's Wireless News List), oldcolo-nsf@warpspeed.com (Old Colorado Wireless NSF Grant List), ss@tapr.org (TAPR SS Mailing List) From: dewayne@warpspeed.com (Dewayne Hendricks) Subject: Comparison of DSSS and FHSS - FYI [Note: I got this from the Solectek website at . They make Part 15 wireless data gear.] Tech Tips, Dec. '95 While enjoying the serenity of radio silence and cooking the family turkey for the Thanksgiving dinner in a microwave oven (see last month's Tech Tips), I thought I should sneak in a more controversial topic for December, the silly season. The topic is the wireless LAN FHSS (Frequency Hopping Spread Spectrum) and DSSS (Direct Sequence Spread Spectrum) technology comparison. No, no...I shall not be biased by Solectek's own DSSS product offerings. In a technology judgment, one can't take the fifth amendment. Right? You are the judge and jury. Just to be overwhelmingly fair, I shall talk about the bad things in DSSS first. Current 2 Mbps DSSS products in the market place occupy 22 Mhz of bandwidth at the first nulls of the main signal lobe. FHSS, on the other hand, does it within 1 Mhz of bandwidth as a consequence of FCC mandate. As a result, the circuit design for the DSSS products requires a very good passband characteristics for 22 Mhz wide. If there is a choice of 1 Mhz versus 22 Mhz, any good old non-masochistic RF engineer would shy away from 22 Mhz passband design any day of the year. DSSS is typically chipped using BPSK modulation. BPSK modulation has both phase and amplitude information and thus linear amplification is necessary. What that means is that only Class A or Class AB amplifiers can be used. These are relatively low efficiency amplifiers. A lot of the DC power is turned into thermal energy which has to dissipate. FHSS is typically using CPFSK modulation. This is a constant envelope modulation and thus non-linear high efficiency Class C amplifier is adequate for its use. For that matter, the entire transmit and receive chains can be non-linear as well, whatever that may be. It transpired that DSSS is more power hungry and harder to build in a smaller enclosure than FHSS. In an indoor radio propagation environment, the measured delay spread statistics have shown that 100 nSec delay is reasonably common. This is close to the chipping rate of DSSS. This means a potential for inter-chip-interference, or in other words, a penalty for performance that may be as much as 10 dB over corresponding Gaussian Channel in our experience. Good diversity antennas must be used to overcome some of these problems. There have been arguments that RAKE or equalization implementation may turn this delay phenomenon into an advantage for DSSS, as it has for IS-95 CDMA. But honestly, give me a break, I don't see anyone doing RAKE at 10 Mega Chip for this market any time soon. I certainly don't have any such plans. FHSS folks rest easy and they don't see the effects of the 100 nSec delay even if they tried. For a strong narrow band jammer environment FHSS also has a marked advantage, if it can avoid the jammed channel. Otherwise, FHSS will still degrade its performance gracefully. DSSS on the other hand will simply roll over belly-up. However, in a low broadband interference case, FHSS will roll over dead more than 10 times sooner. This is because FHSS requires a higher over the air signal flux density than DSSS to stay healthy. This explains the observation that FHSS dies sooner than DSSS near a microwave oven. Now that I have trashed the DSSS completely, let me see if I can even up the score just a little with bad things in FHSS. The FCC rule limits the 20 dB bandwidth of a hopping channel to be 1 Mhz wide. To achieve comparable DSSS data speed will require FHSS to use M'ary modulation, where "M" here is a big time Mighty Mary "M." The implementation difficulty is exponential. Furthermore the required Eb/No is greatly increased for the same BER and hence the range is greatly reduced. To compound the problem, FHSS has to give up inter-hop synthesizer settling time and demodulator lock-up time where no data transmission can be done. FHSS is also forced to hop within 0.4 sec. It has to use no less than 75 channels. All this mumbo jumbo means that it very tough to get a high speed FHSS that does more than 1-2 Mbps and if you do, you PAY for it! DSSS on the other hand can do high data speed relatively easily. 10 Mbps DSSS in the 2.4 Ghz band is now available. I think I can fit 20 Mbps DSSS in this band without too much trouble. FHSS has only 1 Mhz bandwidth per hop. DSSS can utilize full bandwidth. Thus DSSS has more frequency diversity protection against frequency select fading phenomenon. I know I am hand waving here, but in real life, 10 Mhz fading statistics is markedly superior over 1 Mhz. As far as power control discussion is concerned, everybody has been over sensitized with CDMA near-far problems. I contend that this problem has minimum effect here. All the 2.4 Ghz roaming adapter products use half-duplex method, and they do CSMA/CA in a time division manner with the access points. The only near-far problem is a "capture" effect where a stronger station always win the spectrum. This goes for both DSSS and FHSS. I think I am going to get roasted on this one. As you can see I am bending over backwards to be fair to both technology camps, if not over compensating for the FHSS guys. To summarize on this rather long winded discussion, you can safely say the following: 1. DSSS is much harder to build, and may cost more. It should always have the data speed and range advantage. 2. FHSS is easier to build and therefore cost less. It is slower in data speed and shorter in range. Of course, here I'm hand waving again...... -jc -------------------------------------------------------------------------- Dewayne Hendricks, WA8DZP ! CIS: 75210,10 AppleLink: D6547 Warp Speed Imagineering ! Internet: dewayne@warpspeed.com 43730 Vista Del Mar ! Packet Radio: WA8DZP @ K3MC.#NOCAL.CA.USA.NOAM Fremont, CA 94539-3204 ! AOL: HENDRICKS Fax: (510) 770-9854 ! WWW: http://www.warpspeed.com/ -------------------------------------------------------------------------- From dewayne@warpspeed.com Fri Dec 01 12:20:48 1995 Received: from warpspeed.com (WA8DZP@odo.warpspeed.com [204.118.182.20]) by sys1.tapr.org (8.7.2/8.7.2) with ESMTP id MAA04949 for ; Fri, 1 Dec 1995 12:20:37 -0600 (CST) Received: from [204.118.182.22] by warpspeed.com with SMTP (Apple Internet Mail Server 1.0); Fri, 1 Dec 1995 10:14:12 -0800 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Fri, 1 Dec 1995 10:14:01 -0800 To: dewayne-net@warpspeed.com (Dewayne's Wireless News List), oldcolo-nsf@warpspeed.com (Old Colorado Wireless NSF Grant List), ss@tapr.org (TAPR SS Mailing List) From: dewayne@warpspeed.com (Dewayne Hendricks) Subject: Article on interference potential of microwave ovens - FYI [Note: I got this from the Solectek website at . They make Part 15 wireless data gear.] Tech Tips, Nov. '95 This month, we shall tackle the issue of the interference potential that microwave ovens pose to wireless LAN operations in the 2.4 GHz ISM band. First, we need to examine the nature of the microwave oven interference. Before we get into it, though, I'd like to digress a little. When I originally looked at this problem in 1989 for IEEE 802.4L committee, I was told of reports from research labs that microwave oven interference consisted of a very pure CW tone at about 2.45 GHz. I was also told that they had measured broadband noise interference of over 100 MHz. The conflicting results prompted me to do some measurements of my own. The end results I got convinced me that both were correct ( I should be a diplomat....). A microwave oven emits a single CW tone on a 50% duty cycle, 8.3 mSec on and 8.3 mSec off. This, by the way, is because they run on a 60 Hz main power (OK, ok, 1/60=16.7 mSec, and so half of 16.7 is 8.3 mSec). During the ON time, the CW tone flickers on and off rapidly like a fluorescent tube. There are zillions of possibilities during the ON period. It may flicker rapidly throughout the ON period, or it may flickers a few times then stay on for the duration. Knowing this, you see the problem that the poor guy who tries to measure this phenomenon faces. Measuring pulsing emission is always a pain even under the best circumstances. The impulse bandwidth characteristics of your measuring instrument, the resolution filter of the measuring instrument's front end, the time/frequency duality of poor Mr. Fourier, the sweep time, etc. are enough variables to drive a sane person nuts. To make a long story short, the rapid flickering which can have a rise and fall time of about 10 nSec causes the broadband noise spread. So there you have it, if the tone stays on for some time, and you are smart enough to catch it on your measuring instrument, you can see a very nice clean CW tone - hint: use DSP techniques. When it flickers, you have a nice passband spectrum plot of your trusty microwave oven's magnetron cavity. Now, if you have 2 or 3 phase main powers, and your microwave ovens are on different phases, then - tough luck, you lose the quiet "OFF" period of the microwave ovens. But there is a way to keep the emission low. The emission power is much less if the oven is loaded. To achieve reasonable radio silence, simply put a 5 lb turkey to cook in each microwave oven. IEEE802.11 MAC has an optional provision to keep clear of the 8.3 mSec ON time, by using a software "primitive" called CCA (Clear Channel Assessment). You can opt not to transmit when CCA is False. However, my experience is that microwave oven interference potential is generally over-rated. The flux density of the interference is not that powerful in most cases. My advice is to simply move away from the oven - with a good wireless LAN adapter, even a distance as little as ten feet will allow a wireless connection that has imperceptible performance degradation. See you next month - jc Further readings: J.Y.C. Cheah, "Interference Characteristics of Microwave Ovens in Indoor Radio Communications", Proceedings of IEEE/IEE PIMRC' 91 London UK, pp. 280-285, September, 1991. J.Y.C. Cheah, "IEEE 802.4L submission on microwave oven interference measurement", Doc: IEEE p802.4/90-08a., February, 1990. -------------------------------------------------------------------------- Dewayne Hendricks, WA8DZP ! CIS: 75210,10 AppleLink: D6547 Warp Speed Imagineering ! Internet: dewayne@warpspeed.com 43730 Vista Del Mar ! Packet Radio: WA8DZP @ K3MC.#NOCAL.CA.USA.NOAM Fremont, CA 94539-3204 ! AOL: HENDRICKS Fax: (510) 770-9854 ! WWW: http://www.warpspeed.com/ -------------------------------------------------------------------------- From srbible@mindport.net Sat Dec 09 13:40:36 1995 Received: from polaris (root@polaris.mindport.net [205.219.167.2]) by sys1.tapr.org (8.7.2/8.7.2) with SMTP id NAA05940 for ; Sat, 9 Dec 1995 13:40:33 -0600 (CST) Received: from polaris.mindport.net (synapse-35.mindport.net [205.219.167.54]) by polaris (8.6.12/8.6.12) with SMTP id OAA13598 for ; Sat, 9 Dec 1995 14:40:27 -0500 Posted-Date: Sat, 9 Dec 1995 14:40:27 -0500 Message-ID: <30C9E64C.1BBC@mindport.net> Date: Sat, 09 Dec 1995 14:41:00 -0500 From: "Steven R. Bible" Organization: Mindport X-Mailer: Mozilla 2.0b3 (Win95; I) MIME-Version: 1.0 To: ss@tapr.org Subject: Zilog Spread Spectrum Chip X-URL: http://twelve.srv.lycos.com/cgi-bin/pursuit?first=51&maxhits=10&minterms=1&minscore=0.01&terse=standard&query=spread+spectrum Content-Type: multipart/mixed; boundary="---------------------------185921475116857" This is a multi-part message in MIME format. -----------------------------185921475116857 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit I stumbled onto this pdf file on the web: Z87200 Spread-Spectrum Product Description http://www.zilog.com/wireless/Z87200.pdf The Zilog wireless page is: http://www.zilog.com/wireless/wireless.html 73, - Steve, N7HPR srbible@mindport.net n7hpr@amsat.org n7hpr@tapr.org -----------------------------185921475116857 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="pursuit" Lycos search: spread spectrum

Lycos, Inc. - The Catalog of the Internet

Lycos is hiring. Examine the exciting opportunites at Lycos.
Lycos now 10x bigger than the nearest competitior - read the Web Catalog Size report.

Lycos search: spread spectrum

Lycos Dec 6, 1995 catalog, 16454008 unique URLs


Found 22896 documents matching at least one search term.
Printing the next 10 of 11955 documents with at least scores of 0.010.

Found 74 matching words (number of documents): spread (9875), spectrum (22896), ...

51) Semester/Diplomarbeit von zimmi (1) [0.7751, 2 of 2 terms, adj 1.0]

Outline: Single-Chip Spread-Spectrum Modem

Abstract: Entwurf Digitaler Integrierter Schaltungen Semester/Diplomarbeit für 2 Studenten Spread-Spectrum-Systeme ermöglichen eine robuste drahtlose Datenübertragung in Gebäuden (wireless LAN), benötigen jedoch einen erheblichen Aufwand an digitaler
http://err.ethz.ch/SADA/ws95/zimmi1.html (1k)

52) Basic Spread Spectrum Info Functions Network Capacity FCC License Coverage Ven [0.7741, 2 of 2 terms, adj 1.0]

Outline: Basic Spread Spectrum Info Functions Network Capacity FCC License Coverage Vendors

Abstract: * poletop repeating/routing from point to point * Access to campus networks and computers * Access to commercial database services * Very large, scalable * None required * In-building * Central campus * Extended
http://choices.cs.uiuc.edu/schools/declan/declan.spread.html (1k)

53) Frequency-Hopped Spread Spectrum Baseband Architecture [0.7733, 2 of 2 terms, adj 1.0]

Abstract: Frequency-Hopped Spread Spectrum Baseband Architecture

http://www.icsl.ucla.edu/icsl-lab/baseband-arch.html (0k)

54) Amateur Radio Technology [0.7731, 2 of 2 terms, adj 1.0]

Outline: Amateur Radio Satellites Microwave Slow Scan Television Software Spread Spectrum Standards and Protocols

Abstract: AMSAT Everything you ever wanted to know about amateur radio satellites. SatTrack Satellite tracking software for UNIX + X Window System. The Microwave Journal Technical publication for microwave design engineers. Varian Crossed Field & Receiver Protector Products - Microwave product info (and some good introductory tutorials about TWT and magnetron operation). WB2OSZ's SSTV Handbook The Slow Scan Bible. * Linux *UNIX *Satellite Tracking * SatTrack *MS
http://ve7tcp.ampr.org/Technology/ (2k)

55) Spread Spectrum, Inc. [0.7674, 2 of 2 terms, adj 1.0]

Abstract: Spread Spectrum, Inc.

http://web1.digital.net/~spectrum/ (0k)

56) Spread Spectrum Info [0.7672, 2 of 2 terms, adj 1.0]

Outline: Spread Spectrum Info

Abstract: My Wireless Overview OTA Wireless Technology Impact Study Establishment of Federal Wireless Policy Committee Here's a neat piece of tech, but not available here
http://choices.cs.uiuc.edu/schools/declan/declan.wireless.html (1k)

57) Spread Spectrum Modems [0.7660, 2 of 2 terms, adj 1.0]

Abstract: Spread Spectrum Modems

http://www.elektrobit.fi/ss1.html (0k)

58) Spread Spectrum and the Amateur Radio Service - Recent Developments [0.7649, 2 of 2 terms, adj 1.0]

Abstract: Spread Spectrum and the Amateur Radio Service - Recent Developments

http://www.tapr.org/ss/psr60ss.html (0k)

59) Spread Spectrum Information [0.7649, 2 of 2 terms, adj 1.0]

Abstract: Spread Spectrum Information

http://www.teatherless.com/spread_spectrum.html (0k)

60) Z87200 Spread-Spectrum Product Description [0.7639, 2 of 2 terms, adj 1.0]

Abstract: Z87200 Spread-Spectrum Product Description

http://www.zilog.com/wireless/Z87200.pdf (0k)

Next 10 hits

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-----------------------------185921475116857-- From srbible@mindport.net Sat Dec 09 14:07:22 1995 Received: from polaris (root@polaris.mindport.net [205.219.167.2]) by sys1.tapr.org (8.7.2/8.7.2) with SMTP id OAA07124 for ; Sat, 9 Dec 1995 14:07:20 -0600 (CST) Received: from polaris.mindport.net (synapse-35.mindport.net [205.219.167.54]) by polaris (8.6.12/8.6.12) with SMTP id PAA14334 for ; Sat, 9 Dec 1995 15:07:17 -0500 Posted-Date: Sat, 9 Dec 1995 15:07:17 -0500 Message-ID: <30C9EC97.1312@mindport.net> Date: Sat, 09 Dec 1995 15:07:51 -0500 From: "Steven R. Bible" Organization: Mindport X-Mailer: Mozilla 2.0b3 (Win95; I) MIME-Version: 1.0 To: ss@tapr.org Subject: Zilog Wireless Evaluation Kits X-URL: http://www.zilog.com/thirdper/wireles2.html Content-Type: multipart/mixed; boundary="---------------------------274682893022117" This is a multi-part message in MIME format. -----------------------------274682893022117 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit Found this also: http://www.zilog.com/thirdper/wireles2.html Zilog has two evaluation kits. The Z8700001ZC0 - a cordless telephone chipset evaluation unit, and Z8720000ZC0 - a spread spectrum evaluation unit. I have no idea as to their cost. 73, - Steve, N7HPR srbible@mindport.net n7hpr@amsat.org n7hpr@tapr.org -----------------------------274682893022117 Content-Type: text/html; charset=us-ascii Content-Transfer-Encoding: 7bit Content-Disposition: inline; filename="wireles2.html"

ZILOG Wireless Devices

The data sheets below are Adobe Acrobat .pdf files. You will need to download the Acrobat Reader to view them.

Z8700001ZC0 Evaluation Kit

Z8720000ZC0 Evaluation Kit

Return to Development Tools

Copyright (c) 1995 Zilog, Inc.
-----------------------------274682893022117-- From dewayne@warpspeed.com Sat Dec 16 10:18:51 1995 Received: from warpspeed.com (WA8DZP@odo.warpspeed.com [204.118.182.20]) by sys1.tapr.org (8.7.2/8.7.2) with ESMTP id KAA15455 for ; Sat, 16 Dec 1995 10:18:46 -0600 (CST) Received: from [204.118.182.22] by warpspeed.com with SMTP (Apple Internet Mail Server 1.0); Sat, 16 Dec 1995 08:18:55 -0800 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Sat, 16 Dec 1995 08:18:40 -0800 To: ss@tapr.org (TAPR SS Mailing List) From: dewayne@warpspeed.com (Dewayne Hendricks) Subject: New SS News related website - FYI SS Gang: Spread Spectrum Scene now has a website. Below is some info on the site: The only publication dedicated exclusively to the art and science of Spread Spectrum digital communications, Spread Spectrum Scene (aka SSS) is targeted for the Spread Spectrum professional and is committed to being the primary source for the latest news and information about the growth, regulation, and opportunities in this emeging science. Spread Spectrum Scene presents industry news, new product information and applications solutions in an easy to read, concise format. Technical contributions and user oriented articles are welcomed. News and press releases will also be published on a space and time available basis. SSS is presented as a service of RF/Spread Spectrum (aka RF/SS), a leader in the custom development of RF, Digital Data Communication and Spread Spectrum Products. Check out their site at: -- Dewayne -------------------------------------------------------------------------- Dewayne Hendricks, WA8DZP ! CIS: 75210,10 AppleLink: D6547 Warp Speed Imagineering ! Internet: dewayne@warpspeed.com 43730 Vista Del Mar ! Packet Radio: WA8DZP @ K3MC.#NOCAL.CA.USA.NOAM Fremont, CA 94539-3204 ! AOL: HENDRICKS Fax: (510) 770-9854 ! WWW: http://www.warpspeed.com/ -------------------------------------------------------------------------- From wd5ivd@tapr.org Sat Dec 16 12:05:14 1995 Received: (from wd5ivd@localhost) by sys1.tapr.org (8.7.2/8.7.2) id MAA19057 for ss@tapr.org; Sat, 16 Dec 1995 12:05:12 -0600 (CST) From: Greg Jones Message-Id: <199512161805.MAA19057@sys1.tapr.org> Subject: Re: [SS:13] New SS News related website - FYI To: ss@tapr.org Date: Sat, 16 Dec 1995 12:05:12 -0600 (CST) In-Reply-To: from "Dewayne Hendricks" at Dec 16, 95 10:21:30 am X-Mailer: ELM [version 2.4 PL24] Content-Type: text Looks like they have a lot of work to do before the pages are fully operational. Cheers - Greg > > SS Gang: > > Spread Spectrum Scene now has a website. Below is some info on the > site: > > The only publication dedicated exclusively to the art and science of Spread > Spectrum digital communications, Spread Spectrum Scene (aka SSS) is > targeted for the Spread Spectrum professional and is committed to being the > primary source for the latest news and information about the growth, > regulation, and opportunities in this emeging science. > > Spread Spectrum Scene presents industry news, new product information and > applications solutions in an easy to read, concise format. Technical > contributions and user oriented articles are welcomed. News and press > releases will also be published on a space and time available basis. > > SSS is presented as a service of RF/Spread Spectrum (aka RF/SS), a leader > in the custom development of RF, Digital Data Communication and Spread > Spectrum Products. > > Check out their site at: > > > > > -- Dewayne > > > -------------------------------------------------------------------------- > Dewayne Hendricks, WA8DZP ! CIS: 75210,10 AppleLink: D6547 > Warp Speed Imagineering ! Internet: dewayne@warpspeed.com > 43730 Vista Del Mar ! Packet Radio: WA8DZP @ K3MC.#NOCAL.CA.USA.NOAM > Fremont, CA 94539-3204 ! AOL: HENDRICKS > Fax: (510) 770-9854 ! WWW: http://www.warpspeed.com/ > -------------------------------------------------------------------------- > > > > > From dewayne@warpspeed.com Wed Dec 20 15:02:19 1995 Received: from warpspeed.com (WA8DZP@odo.warpspeed.com [204.118.182.20]) by sys1.tapr.org (8.7.2/8.7.2) with ESMTP id PAA03649 for ; Wed, 20 Dec 1995 15:02:12 -0600 (CST) Received: from [204.118.182.22] by warpspeed.com with SMTP (Apple Internet Mail Server 1.0); Wed, 20 Dec 1995 13:02:04 -0800 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Wed, 20 Dec 1995 13:01:48 -0800 To: ss@tapr.org (TAPR SS Mailing List) From: dewayne@warpspeed.com (Dewayne Hendricks) Subject: ARLB112 Spread spectrum changes ZCZC AG79 QST de W1AW ARRL Bulletin 112 ARLB112 >From ARRL Headquarters Newington CT Relayed by KB8NW/OBS & BARF-80 BBS December 19, 1995 To all radio amateurs SB QST ARL ARLB112 ARLB112 Spread spectrum changes The ARRL has asked the Federal Communications Commission to relax its spread-spectrum regulations to give Amateur Radio more opportunity to contribute to spread-spectrum development. The League's petition for rulemaking, filed in December, seeks relaxed restrictions on spreading sequences and greater flexibility in spreading modulation. The spread-spectrum technique, which distributes information among several synchronized frequencies within a band at the transmitter and reassembles the information at the receiver, was first approved for Amateur Radio in 1985 for bands above 225 MHz, and there has been some experimental amateur operation since then. The petition proposes that the FCC permit brief test spread-spectrum transmissions and allow international spread-spectrum communications between amateurs in the US and those in countries that permit hams to use spread-spectrum techniques. The current rules allow only domestic communication. The petition also asks for automatic power-control provisions to insure use of minimum necessary power to conduct spread-spectrum communication and limit the potential for interference to narrowband modes. The petition does not ask for any changes in frequency restrictions on SS emissions, the 100 watt power limit or logging and identification requirements. In urging the FCC to adopt the changes, the League's petition calls the proposals the minimum necessary changes in order to foster SS experimentation in the Amateur Service. -------------------------------------------------------------------------- Dewayne Hendricks, WA8DZP ! CIS: 75210,10 AppleLink: D6547 Warp Speed Imagineering ! Internet: dewayne@warpspeed.com 43730 Vista Del Mar ! Packet Radio: WA8DZP @ K3MC.#NOCAL.CA.USA.NOAM Fremont, CA 94539-3204 ! AOL: HENDRICKS Fax: (510) 770-9854 ! WWW: http://www.warpspeed.com/ -------------------------------------------------------------------------- From bm@lynx.ve3jf.ampr.org Sun Dec 31 09:59:50 1995 Received: from lynx.ve3jf.ampr.org (lynx.ve3jf.ampr.org [44.135.96.100]) by sys1.tapr.org (8.7.2/8.7.2) with SMTP id JAA25979 for ; Sun, 31 Dec 1995 09:59:45 -0600 (CST) Received: (from bm@localhost) by lynx.ve3jf.ampr.org (8.6.12/8.6.12) id PAA01384 for ss@tapr.org; Sun, 31 Dec 1995 15:59:04 GMT From: Barry McLarnon VE3JF Message-Id: <199512311559.PAA01384@lynx.ve3jf.ampr.org> Subject: SS Questions To: ss@tapr.org Date: Sun, 31 Dec 1995 15:59:02 +0000 (GMT) X-Mailer: ELM [version 2.4 PL23] Content-Type: text I've been collecting info on the various SS wireless LAN products, particularly those which can do >100 kbps. I'm capturing the data in a spreadsheet, and when I get a little further along, I'll HTML'ize it and make it available on the Web. I may be reinventing the wheel here, but so far I haven't come across any compilation of product info like this... if anyone knows of one, a pointer would be appreciated. The URL http://pasture.ecn.purdue.edu/~laird/Electronics/wireless-modems/ has a bit of relevant info, but it's very incomplete... I'm trying to do a much more comprehensive survey (and in '96, to get my hands on some of the hardware!). I'm curious as to what distances have been achieved with these unlicenced WLAN systems over good (and not so good) LOS paths. I know that there are wireless bridge products that can span considerable distances (e.g., from Cylink), but they tend to be very expensive. What about the lower-cost products such as the WaveLAN cards? Anybody with some real-world experience with outdoor links out there? (Yes, I'm aware of Lew Shannon's tests over a half-mile path). Another thing which interests me is the MAC layer implementations used in these products. As far as I can tell, nearly all of these products are half-duplex (again, Cylink being an exception) and use CSMA. I know that WaveLAN uses CSMA/CA, but I've not found any details on its CA implementation... are the strategies used similar to those proposed in the IEEE 802.11 draft? Are there any existing or proposed unlicenced WLAN products which use CDMA? Barry -- Barry McLarnon VE3JF/VA3TCP Ottawa Amateur Radio Club Packet Working Group Email: bm@hydra.carleton.ca or bm@lynx.ve3jf.ampr.org From srbible@mindport.net Sun Dec 31 19:19:25 1995 Received: from polaris.mindport.net (root@polaris.mindport.net [205.219.167.2]) by sys1.tapr.org (8.7.2/8.7.2) with SMTP id TAA13116 for ; Sun, 31 Dec 1995 19:19:22 -0600 (CST) Received: from sabible (DIAL6.GREENEVILLE.ILINKGN.NET [199.172.21.137]) by polaris.mindport.net (8.6.12/8.6.12) with SMTP id UAA13699 for ; Sun, 31 Dec 1995 20:19:16 -0500 Date: Sun, 31 Dec 1995 20:19:16 -0500 Posted-Date: Sun, 31 Dec 1995 20:19:16 -0500 Message-Id: <199601010119.UAA13699@polaris.mindport.net> X-Sender: srbible@mindport.net X-Mailer: Windows Eudora Light Version 1.5.2 Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" To: ss@tapr.org From: "Steven R. Bible" Subject: Re: [SS:16] SS Questions At 10:15 AM 12/31/95 -0600, you wrote: >I've been collecting info on the various SS wireless LAN products, >particularly those which can do >100 kbps. I'm capturing the data in a >spreadsheet, and when I get a little further along, I'll HTML'ize it and >make it available on the Web. I may be reinventing the wheel here, but >so far I haven't come across any compilation of product info like >this... if anyone knows of one, a pointer would be appreciated. The URL >http://pasture.ecn.purdue.edu/~laird/Electronics/wireless-modems/ has a >bit of relevant info, but it's very incomplete... I'm trying to do a >much more comprehensive survey (and in '96, to get my hands on some of >the hardware!). Barry, the only other list that would come close is one I have written listing other web sites of interest concerning SS products, including commercial. See the URL http://www.tapr.org/ss/other.html This page has proven to be very popular. It receives more hits that all the rest of the SS pages I've written. If you would like Barry, you could link your page from here. Steve, N7HPR (srbible@mindport.net, n7hpr@amsat.org, n7hpr@tapr.org) From dewayne@warpspeed.com Sun Dec 31 21:25:33 1995 Received: from warpspeed.com (WA8DZP@odo.warpspeed.com [204.118.182.20]) by sys1.tapr.org (8.7.2/8.7.2) with ESMTP id VAA16468 for ; Sun, 31 Dec 1995 21:25:29 -0600 (CST) Received: from [192.160.122.15] by warpspeed.com with SMTP (Apple Internet Mail Server 1.0); Sun, 31 Dec 1995 19:25:35 -0800 Message-Id: Mime-Version: 1.0 Content-Type: text/plain; charset="us-ascii" Date: Sun, 31 Dec 1995 19:25:17 -0800 To: ss@tapr.org From: dewayne@warpspeed.com (Dewayne Hendricks) Subject: Re: [SS:17] Re: SS Questions At 19:37 12/31/95, Steven R. Bible wrote: >Barry, the only other list that would come close is one I have written >listing other web sites of interest concerning SS products, including >commercial. See the URL > > http://www.tapr.org/ss/other.html > >This page has proven to be very popular. It receives more hits that all the >rest of the SS pages I've written. If you would like Barry, you could link >your page from here. I would try the following site, WIRELESS WORLD By Tim Cocklin: It has pointers to most commercial wireless product sites on the Web and lots of other useful info. It really is a first class effort and where I first go when I'm researching a wireless topic!! -- Dewayne -------------------------------------------------------------------------- Dewayne Hendricks, WA8DZP ! CIS: 75210,10 AppleLink: D6547 Warp Speed Imagineering ! Internet: dewayne@warpspeed.com 43730 Vista Del Mar ! Packet Radio: WA8DZP @ K3MC.#NOCAL.CA.USA.NOAM Fremont, CA 94539-3204 ! AOL: HENDRICKS Fax: (510) 770-9854 ! WWW: http://www.warpspeed.com/ --------------------------------------------------------------------------