kwongj@caldwr.UUCP (James Kwong) (11/23/88)
Laser Communications, Inc. sells a laser beam product that - "Link Ethernet backbones atmospherically by laser beam to connect site up to 1 kilometer apart without cables or FCC licensing". The brochure says that speeds is up to 10 megabits per second in all weather. Low level output is harmless under even the most unlikely operating conditions. The price is around $14,000 for two units. Anyone has experience with this product or any similar product that they might want to share with me. Reply by e-mail would be fine. Thanks -- James Kwong Calif. Depart. of H2O Resources, Sacramento, CA 95802 caldwr!kwongj@ucdavis.edu(Internet) ...!ucbvax!ucdavis!caldwr!kwongj (UUCP) The opinions expressed above are mine, not those of the State of California or the California Department of Water Resources.
dhesi@vector.uucp (Rahul Dhesi) (12/01/88)
In article <telecom-v08i0186m01@vector.UUCP> kwongj@caldwr.UUCP writes: >Laser Communications, Inc. sells a laser beam product that - >"Link Ethernet backbones atmospherically by laser beam to connect >site up to 1 kilometer apart without cables or FCC licensing". The FCC controls all broadcasting. The difference between a beam of light and a shortwave transmission is just the frequency (wavelength). Does the Communications Act, or other legislation that gives the FCC authority over broadcasting, specify the frequency beyond which the FCC has no jurisdiction? If not, shining any beam of light, unless specifically authorized by the FCC, is probably illegal. Not only outdoor lasers, but also automobile headlights, are probably in violation. -- Rahul Dhesi UUCP: <backbones>!{iuvax,pur-ee}!bsu-cs!dhesi
ron@ron.rutgers.edu (Ron Natalie) (12/02/88)
These guys had a mini demonstration at ComNet last year. They've been promising to demo the thing to Rutgers for nearly two years now. It seems like they might just be getting close now. I'll let people know when they actually deliver. -Ron
doug@merch.TANDY.COM (Doug Davis) (12/02/88)
Sorry the FCC has absolutly *NOTHING* to do with lasers, All forms of
laser and coherent radient emitting devices are controled by the
Food and Drug administration. Lasers are specifically covered in
CFR-21 parts 1000.00 - 1040.30, stat 44 FR 52195 1979, and sec 358,
stat 82 1177-1179 (42 U.S.C. 263F) Incidently these same areas
cover all federal regulations on *LIGHT* emitting produces, such
as the afformention automotive headlights.. Almost anyone who
commercially deals in a wide varity of lasers should be able to provide
you with copies of the relivent sections.
doug davis
--
LaserOptic
1030 Pleasent Valley Lane
Arlington Texas 76015
(817)-467-3740
{ motown!sys1, uiucuxc!sys1, texbell}!dougdonp@apollo.COM (Don Preuss) (12/08/88)
The National Institutes of Health has one of these set up between two buildings. It took the company a few trys to get it right, and the latest I heard was that they are still getting a large number of retransmits. It would seem to me that you would get a "loss of signal" during rain or snow storms. This doesn't seem like a wonderfully reliable system unless there were some kind of backup. Also, If the laser was strong enough to punch through the rain, wouldn't you zap birds with it? donp -- Arpa: donp@apollo.com UUCP: uunet!mit-eddie!apollo!donp
jbn@glacier.stanford.edu (John B. Nagle) (12/12/88)
This comes up every once in a while, and the definitive information is as follows. The FCC has jurisdiction over "Radio", according to the Communications Act of 1934, as amended. "Radio Waves or Hertzian Waves" are defined in 47 CFR Ch. 1 part 2 subpart A section 2.1 as "Electronic waves of frequencies arbitrarily lower than 3,000 GHz, propagated in space without artificial guide." So FCC regulation stops at 3,000 GHz. The 3,000 GHz limit is by international agreement (Radio Regulations, Geneva, 1982). This limit is in the very long infrared range. In article <telecom-v08i0196m06@vector.UUCP> donp@apollo.COM (Don Preuss) writes: >X-Administrivia-To: telecom-request@vector.uucp >X-TELECOM-Digest: volume 8, issue 196, message 6 > >The National Institutes of Health has one of these set up >between two buildings. It took the company a few >trys to get it right, and the latest I heard was that they >are still getting a large number of retransmits. Rain and snow are serious problems. One thing that helps is to use large collecting optics at both ends, so that the beam occupies a physically larger diameter but remains collimated. Usually a large parabolic reflector is used. This will improve operation in light rain and snow. In heavy precipitation, though, optical systems just don't work. To get through heavy rain, you must use a wavelength bigger than raindrops. John Nagle