Victoria to Port Angeles Wireless Link

http://www.dailywireless.org/images/up/portangeles.jpg

On February 29, 2004, PersonalTelco's AaronBaer held an [http://www.personaltelco.net/index.cgi/AntennaModWorkshop Antenna Workshop] where we assembled biquad antennas based on the design by [http://trevormarshall.com/biquad.htm Trevor Marshall]. When joined to a PrimeStar dish, the combined units should produce a gain of 30db. A similar design in Western Australia near Perth, resulted in a 30 mile range over the ocean.

The goal is to create hardware for an international link, from Canada to the United States over the Strait of Juan de Fuca, the major shipping channel that divides the two countries.

The [http://www.portangeles.org/ city of Port Angeles, Washington] is some 30 miles from Victoria British Columbia. On July 10th a "free" 802.11a link will be attempted between these two cities.

VictoriaPortAngelesParty

• http://www.dailywireless.org/images/up/portangelesmap.jpg http://www.dailywireless.org/images/up/linkmap.jpg http://www.dailywireless.org/images/up/vancouvermap.jpg

Here's [http://terraserver.homeadvisor.msn.com/image.aspx?t=2&s=16&x=36&y=417&z=10&w=2 The Terraserver] for maps and [http://mapper.acme.com/ Acme Mapper] for photos.

[http://trevormarshall.com/biquad.htm Trevor Marshall's biquad design] (see [http://martybugs.net/wireless/biquad/ here] for detailed construction info), feeding a Primestar satellite dish has established [http://www.erlang-software.com/FreeNet/Rottnest has established a solid 30 mile capability] with 10-15 dB (SNR) link from Rottnest Island off the West Australian coast, to a number of APs on the escarpment east of Perth; a distance of 48 km (30 miles).

http://trevormarshall.com/bq-mount-thumb.jpg

http://trevormarshall.com/bq-front-thumb.jpg

http://martybugs.net/wireless/biquad/images/biquad_size.png

Technical Approaches

[http://www.trevormarshall.com/waveguides.htm Trevor Marshall], [http://www.e3.com.au/ Perth's Community LAN site, E-3], and [http://www.everettwireless.net/index.php Everett Wireless] have been building [http://members.iinet.net.au/~clark/FreeNet/Workshop.htm homebuilt waveguides].

Here's [http://www.dailywireless.org/modules.php?name=News&file=article&sid=683 a +22 dB design] made from [http://www.everettwireless.net/modules.php?op=modload&name=phpBB_14&file=index&action=viewtopic&topic=14&forum=4&1 aluminum foil and styrofoam].

http://www.sdots.com/photos/waveguides.jpg

[http://www.overclockers.com.au/article.php?id=118207 Tests with Long-Distance Waveguides] look good but a PrimeStar dish will provide more gain, as it's much more directional. Slotted waveguides are definitely not suited to point-to-point links, as they are omni-directional, while a PrimeStar dish is very directional.

The 5.8 GHz Option

The 5 GHz band has about 8 dB more loss than 2.4 GHz at long range. With 6 db loss, range is halved. So 5.8GHz will need more than twice the gain.

[http://www.atheros.com/pt/index.html Atheros Xtended range chips] claims receive sensitivities up to -105dBm. That's more than 10-20 dB better than other 802.11 chips. [http://www.dailywireless.org/modules.php?name=News&file=article&sid=2005&mode=&order=0&thold=0 Atheros claims XR will triple the range] for their dual-band, AR 5004. [http://www.atheros.com/pt/AR5004XBulletin.htm The Atheros 5004x] brings "Xtended Range" to the 5.8 GHz band.

http://common.ziffdavisinternet.com/util_get_image/5/0,3363,sz=1&i=54867,00.gif

[http://www.netgear.com/products/details/WGT624.php?view= Netgear's WGT624] uses Super G technology. http://www.netgear.com/images/products/large/wgt624.jpg D-Link's [http://www.dlink.com/products/?pid=6 DI-624 Wireless Router], their [http://www.dlink.com/products/?pid=241 DWL-G810 "G" bridge] and Netgear's [http://www.dailywireless.org/modules.php?name=News&file=article&sid=1913 WGT634U Wireless Media Router] use them. Right now they're "G" only. But a dual-band 802.11a/g wireless router that doubles as a bridge might provide increased range and sensitivity at 5 GHz.

http://img.cmpnet.com/eet/news/03/september/ATHEROS1287_PG_45.gif

[http://www.commsdesign.com/news/OEG20030915S0060 The AR5004X 802.11a/g chip set with XR], can reach distances of over 700 meters, but the XR technology is a two-way technique that must also be implemented in an access point.

You might feed a couple [http://www.proxim.com/products/bwa/multipoint/mp11/mp11a/ Proxim MP.11a] bridges ($600) into a [http://www.hyperlinktech.com/web/amplifiers_5800.php 500mw, 5.8 GHz amp] ($675), with a [http://www.ydi.com/products/58ghz-fp28.php 28 dBi 5.8 GHz flat panel] ($535) on each side. [http://www.atheros.com/pt/AR5004XBulletin.htm [http://www.ydi.com/calculation/som.php YDI's Operating Margin Calculator] can help you estimate operating range.

[http://usa.asus.com/products/communication/wireless/wl-330/overview.hTm The tiny Asus Access Point] can also be used as a bridge. A long distance link might simply use a +23db, 5.8 GHz flat panel, with an Atheros Xtrended Range bridge plugged in. [http://www.dailywireless.org/modules.php?name=News&file=article&sid=1926 Could 100 mile WiFi Video] be possible?

References

• [http://www.narx.net/~chrisk/WaFreeNet/GalaxyMod/ ChrisK's Galaxy Mod]

• [http://martybugs.net/wireless/conifermods.cgi Modifying Conifer Antennas for Wireless Networking]

• [http://www.leemingwireless.net/modules.php?name=Content&pa=showpage&pid=1' Leeming Wireless Network - Dish Mod]

• [http://www.mrx.com.au/wireless/ConfierModifications.htm Conifer 2.4GHz Antenna Modifications for Wireless LAN]

• [http://www.ashtec.dyndns.org/ashtec/mods/index.html How to modify an Ex-Galaxy Antenna for Wireless Network]

• [http://martybugs.net/wireless/conifertest.cgi Conifer Antenna Testing (part 1)]

• [http://martybugs.net/wireless/conifertest2.cgi Conifer Antenna Testing (part 2)]

• [http://martybugs.net/wireless/biquad/ Biquad Antenna Construction]