Wireless Resources

Local Downloads & Resources

Remote Links

Microwave Propagation

• A Primer for Digital Experimenters

Link Budget Calculation

• Can I reach an SVWUX access point?

You can make an estimate by calculating a link budget in dBm. Sum the dB of the transmit power, antenna gains and cable losses at both ends with path loss. If your result is comfortably above -75 dBm, you have a reasonable hope of sustaining a multimegabit connection. You may fill in the form as follows:

• An EWN AP typically transmits 18 dBm of power through a 18 dBi panel antenna.
• Enter a distance at 2.8 GHz to calculate path loss
• Your FCC legal antenna gain, such as from one of these (Not an endorsement of this dealer or manufacturer.)
• Your site cable loss
• Your target receive strength for your desired bitrate. Higher bitrates demand stronger signals. See datasheet for receiver sensitivity available at various data rates. Put that dBm value in this field and calculate your result.

Interference from obstacles or other transmitters may demand a greater "link margin" above the target values above. The greater your margin, the more reliable and faster will be your connection.

Links About 802.11

• Seattle Wireless
• www.openwrt.org OS distros

Software

• Kismet A cross platform, 802.11 layer2 wireless network detector, sniffer, and intrusion detection system

Radio Modulation Schemes

• An in-depth discussion of using OFDM on UHF.
• An overview of the Time Sychronized Mesh Protocol from Dust Networks

Links About APRS

• Xastir APRS map display software: www.xastir.org
• A source for 2006 Tiger/Line maps for Xastir
• APRS callsign map search with APRS World
• Bob Bruninga main site
• APRS Repeaters
• Voice Alert
• California APRS list/group
• KE6AFE Cap Pennel's APRS page
• Local network analysis page
• Winlink messeges via APRS
• APRS Multiline Protocol
• Source for the APRSD daemon for Linux

Links About AX.25

• AX.25 drivers for Windows (and TCP/IP over AX.25): SV2AGW
• Email over AX.25 with the Winlink System

Free Space Optical Technology

• Converting IrDA to use Lasers

Battery Technology

• A discussion of Deep Cycle batteries.

Advanced RF Calculations

• Splat! An RF Signal Propagation, Loss, And Terrain analysis tool for the spectrum between 20 MHz and 20 GHz

Equipment for evaluation (Most are no longer being considered)

A collection of products of possible interest but not yet reviewed

Network

Radio Manufacturers

• Hyperlinktech Radio components: Antennas, amplifiers, connectors, etc.
• Teletronics
• Ubiquity Networks Wireless ISP Equipment Manufacturer
  • Very low cost
  • Linux SDK Support
  • See Streakwave for prices
  • In particular, look at the Bullet and Bullet HP.

Specific Devices

802.11g

• Engenius EUB-3701 EXT A USB Stick with detachable RP-SMA $30 (pending release)

802.11a

• DLink DWL-8200AP About $400 a/g managed AP
• DLink DWL-7700AP About $800 Outdoor a/g AP
• Engenius EOC-8610S-EXT $230 IP67 Enclosed 802.11a AP
• Shireen Octopus 5.8 GHz: $400 each. Can link up to 60 miles.
• Solectek SkyWay 7000 Series 5.8 GHz

801.11n

• Cisco Aironet 1250 Multiband. Rugged "Indoor" Application

EOC Equipment

VoIP

• Linksys VoIP Sets

Operations Software

• Advanced Incident Response System (AIRS) Project: An IPv6 system with some purpose related to incident command and communication. Website is made up mostly of marketing adjectives and little usable detail. Posted for comparison and ideas.
• The Tickets System. An open source GIS and dispatching system that tracks incidents and the resources used to support them.
• The Sahana Disaster Management and GIS System.

Resellers

Resellers of lots of pertinent equipment

• http://www.streakwave.com
• http://www.fab-corp.com
  • Affordable very high gain antennas
    • 2.4 GHz, 13-24 dBi $30-60
    • 5 GHz 17-32 dBi $40-250