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A survey conducted by the ARRL Technology Task Force, of League members and other amateurs revealed that the number one interest in new technologies was in high-speed digital networks. Some suggestions were:
High-speed data links (up to 20 Mbit/s)
Ethernet at 2 Mbit/s on 10 GHz using Sofan Gunplexers
Encourage development of a high-speed amateur digital network
High-speed digital audio/video
In January 2001, the ARRL Board of Directors voted unanimously that the ARRL should proceed with the development of High Speed Digital Networks for the Amateur Service. The ARRL President was to appoint a group of individuals knowledgeable in the field from the international Amateur community and industry. The group would report to the Technology Task Force.
This charter encourages the use of spread spectrum modes of communications such as IEEE 802.11b on amateur radio frequencies bringing a new meaning to the term "radio relay." Today an individual can obtain an amateur radio license with a straight forward written test and no Morse Code required. Then they can run up to 100 watts on sprea d spectrum modes such as IEEE 802.11b and connect their "access point" to any antenna they prefer.
As development progresses, the amateur radio high-speed digital system could have the following key characteristics:
The system should be capable of multiple transmission rates of at least 56 kilobits per second (kbit/s), for example: 128 kbit/s (which is the most common video conferencing rate) and 384 kbit/s (which provides good quality video and audio), 384 to 2 Mbit/s (which can produce broadcast quality video).
Bandwidths should be selected for overall spectrum efficiency. For example a 384-kbit/s transmission rate could be accommodated within a 442-kHz bandwidth using GMSK modulation (K = 1.15). Higher order modulations could be used but by sacrificing signal-to- noise ratio. The system should promote maximum spectrum reuse.
Amateur bands above 420 MHz should be used, particularly those in the range 1240 MHz - 47.2 GHz.
The system should support multimedia modes of voice, data (including messaging, telemetry, telecommand and geolocation beyond Automatic Position Reporting System (APRS), and images (still and video).
Interconnection to the Internet, amateur radio packet, voice and amateur television (ATV) repeaters should be accommodated.
Half- and full-duplex modes and multipoint (including roundtable) operation should be supported.
Some attention will be paid to content to attract newcomers and keep people interested. For example, the system could display a Web page type of screen.
Latency (delay) should be minimized so that users see the system as responsive. Low latency also facilitates, and is necessary for, full-duplex communication.
There should be multiple access to the frequencies, such as packet radio, to obviate constant occupancy such as full-time streaming video.
Terrestrial relays (including multimedia repeaters) and amateur satellites should form the network.
To keep user costs as low as possible, designs should take advantage of widely available technologies, consumer electronics devices, chip sets such as audio/video DSP encoders/decoders, cable modems and existing protocols.
For economies of scale and interoperability (via satellite), the system should have a high degree of interchange and commonality between the Americas, Europe and Asia-Pacific.
Wireless
ethernet using the basic IEEE
802.11b standard
operating under Part
97 of the FCC rules on the 2.4 GHz amateur band.
The IEEE 802.11b standard is what is commonly called Wi-Fi and is the rage among computer buffs. Wi-Fi operates on one of 11 channels authorized by the FCC located and are located around 2.4 GHz under Part 15 (unlicensed operation) of the FCC rules.
The best speed that 802.11b is able to obtain is 11 Mbps, almost 9000 times faster than 1200 baud packet.
The ARRL 802.11 Project calls for operation of the basic IEEE standard by licensed amateur radio operators in the upper part of the 2.4 GHz band while not significantly interfering with other amateur radio activities on that band or Part 15 802.11b operation in the band. Under Part 97 of the FCC rules, amateurs are allowed to run many times the power of Part 15 operation as well as use antennas with unrestricted gain.
IEEE 802.11b channels 1-6 fall totally within the 2.4 GHz ham band. We are recommending that channels 2-5 be used for ARRL 802.11b operation as they do not interfere with other normal amateur radio operations in the band and are not on channels widely used by Part 15 operations. We recommend that channel 5 be used as the primary channel for general ARRL 802.11 network operation. Additionally, we highly recommend that all parties, whenever feasible, completely avoid the use of channel 1 to prevent any possible interference with AO-40 satellite operation.
While IEEE 802.11b allows WEP, an encryption algorithm, Amateur Radio transmissions are characterized as being an open media. That is, amateur radio operators expect and assume that their transmissions are being listened to around the world with no presumption of privacy. And, the FCC even mandates that hams will not encode/encrypt to obscure meaning.
1. Identify and modify as necessary commercial off the shelf (COTS) wireless network interface cards (NICs) and wireless network devices for amateur radio use.
2. Identify or build suitable high gain horizontally polarized omni-directional antennas.
3. Identify and/or build 1-10 watt external bi-directional amplifiers.
4. Modify and/or optimize, if possible, the firmware in the NICs and wireless network devices for operation under Part 97 of the FCC rules.
5. Provide multi-platform hardware drivers and other software for network configuration, operation and maintenance.
Hardware
Firmware
Software
No recommended changes at this time. However, we are working on some ARRL 802.11b issues such as all station use "hsmm" as their SSID, and their amateur callsign in any second SSID (eSSID) or node/AP name. Changes to the IEEE 802.11b protocol are under consideration; however, they will not be finalized until an open call for papers process has been completed and all interested parties have had a chance to comment.
Regulatory
This list has been established to facilitate public discussions of the various aspects of the ARRL 802.11b Project with members of the ARRL HSMM WG and other interested parties who have an interest in the ARRL-802.11b wireless network initiative. The ARRL 802.11b Project would use commercial 802.11b hardware, and additional legal Amateur hardware in Part 97 service. All participants are welcome.
You can join the list by sending E-Mail to
listserv@listserv.tamu.edu
and in the BODY
put SUBSCRIBE arrl-80211b firstname lastname or
SUBSCRIBE arrl-80211b firstname lastname-callsign
Given the increased interest in Amateur applications for 802.11b,
TAPR has decided to add another mailing list for discussions
specifically on its implementation in the Ham Radio world.
The list is designed to be a meeting place for all 802.11b experimenters
regardless of where in the world they are located, or what protocol
changes are being advocated.
If you wish to join this mailing list visit
http://www.tapr.org/cgi-bin/lyris.pl?enter=ham-80211&text_mode=0"
Antennas:
Amplifiers:
Network Interface Devices:
Connectors-Cables-Coax:
Standards and Protocols:
Applications
VoIP:
Tutorials:
License Information:
Amateur Radio Groups:
ARRL 802.11b (Hinternet) Stations:
ARRL 802.11b Local (Hinternet) Groups:
Books
If you have any questions about high-speed digital or multimedia operation, the HSMM Working Group can help you get started in this exciting part of amateur radio. You can contact the ARRL TIS Coordinator directly at tis@arrl.org or by phone at 860-594-0214. The HQ staff will forward your question to high-speed digital experts.
To contact TIS by mail, please send an SASE to:
American Radio
Relay League
Technical Information Service
225 Main St.
Newington, CT 06111
Unleash the power of 802.11b. Get an Amateur Radio Technician License with a straight forward written test from the "technician" question pool. There is no Morse code required to work 802.11b under the FCC Amateur Radio rules. Then run up to 100 watts LEGALLY on your AP using any antenna you would prefer.
Help us fulfill the ultimate dream of a national amateur radio high speed data radio network, with Internet access everywhere for everyone who has an amateur radio license.
To learn more about Amateur Radio, immediately go to the ARRL Web.
The High-Speed Digital Networks and Multimedia Working Group Chairman
is Dr. John Champa, K8OCL.
