This proceeding is available on CD-ROM
- Location:
- Baltimore, Maryland
- Coordinators:
- Greg Jones, WD5IVD
- Paul Rinaldo, W4RI
- Steve Stroh, N8GNJ
- Steve Ford, WB8IMY
- Paul Rinaldo, W4RI
- Hosted by:
- Amateur Radio Research and Development Corp. (AMRAD)
Read the conference story with audio and photos.
Abstracts:
16th ARRL and TAPR Digital Communications Conference
October 11th, 1997
- Amateur Radio and the Linux Operating System
by John Bandy, W0UT - Information: This paper is about moving from MS Windows 3.1 and MS-DOS to MIT X Window and Linux 1.2.13. These operating systems run on the author's PC Intel chips supporting amateur radio applications. This paper will be a comparison based on experience of the two mentioned operating systems. Also are lists of ham radio application software, journals, books, and Internet Sites available for Linux.
- Amateur Radio on Manned Space Vehicles: Improving Amateur Radio's Future Through Enhanced Space Frequencies
by Frank H. Bauer, KA3HDO - Abstract: Since 1982, Amateur Radio has had frequent or continuous presence on space vehicles with astronauts and cosmonauts on-board. To date, tens of thousands of amateur radio operators and their guests have communicated with astronauts and cosmonauts in space. Despite the outstanding success of this facet of amateur radio, it has been plagued with a significant problem -- many parts of the world, including most of the U.S., cannot reliably receive the 2 meter signals from the spaceborne crew members due to severe frequency interference. This problem is even worse for our amateur radio colleagues in space. This paper intends to describe the problem that astronauts and cosmonauts in space and terrestrial amateur radio operators endure to achieve contact success. This paper also provides some high-level recommendations to relieve this problem in the future.
- An AMSAT Mobile TRAKNET
by Bob Bruninga, WB4APR - Conclusion: With the advent of the handheld GPS unit for under $199 has brought thousands of mobile amateur radio operators into the world of mobile data. For years, the growth of amateur GPS applications have been growing at phenomenal rates. At this writing there are mobile map packages available which include the GPS unit for under $150 total! Similarly, the state-of-the-art in automatic PACSAT ground station technology has been improving with many recent software packages to make unattended automatic ground station operations quite easy. The problem is that these two communities of expertise have so far had little cross-interests. It seems that the time is now to merge these technologies into a new amateur application that takes advantage of the unique capabilities of each and fuels the development of an Amateur Radio Mobile Satellite System. Traknet is the opportunity to not only merge these interests into a common purpose, but also to demonstrate Amateur Radio's continuing progress in communications technology.
- APRS Vision System
by Bob Bruninga, WB4APR - Introduction: The APRS Vision System (AVS) was developed to provide a variable bandwidth vision capability for APRS Robotic applications. The system provides an efficient method for image transmission from a mobile or rover and uses the standard APRS UI frame protocol so that the existing APRS digipeater networks can be used for vastly extended range. Using the APRS UI broadcast protocol, not only is there no wasted bandwidth for ACKS, but everyone can monitor the image. A hypothetical idea of driving a robot in New Jersey from a HAM shack in Maryland presents the concept which was so markedly demonstrated this year with the Mars Rover.
- APRServe: An Internet Backbone for APRS
by Steve Dimse, K4HG - Introduction: Last year at the 1996 Digital Communications Conference I predicted that within the next year we would have a working nation-wide APRS backbone running on the Internet. This paper details the progress that has been made towards that goal.
- Keypad Interface Language
by Roy Ekberg, W0LIQ, and Martin Schroedel, K9LTL - Synopsis: ARDS Project was proposed earlier in the Proceedings of the 12th ARRL Digital Communications Conference (held in Tampa, FL, in 1993). During that time, R&D was limited to experiments with Model 12. We renamed ARDS Project Computer Assisted Communications (CAC). This system evolved by experimenting with more models. Model 17 revealed compelling reasons why FCC's 97 part rules need changes that would permit hams to use Keypad interface language with digital signals.
- An All-Software Advanced HF Modem for Amateur Radio
by Matthew Ettus, N2MJI - Winner of Best Technical/theory-oriented Student paper
- Abstract: The need for an inexpensive and robust replacement for 300 baud FSK on the amateur HF bands apparent. A modem was developed which allows for greatly increased data bandwidth (up to 500bps), while at the same time allowing for increased reliability through the use of advanced modulation and coding methods. The entire system runs on a standard PC with a soundcard, under Linux. The only necessary hardware is a mechanism for keying the radio.
- Detection and Estimation of Covert DS/SS Signals Using Higher Order Statistical Processing
by Mamdouh Gouda, Ernest R. Adams, and Peter C.J. Hill - Winner of Best Technical/theory-oriented Student paper
- Abstract: Conventional linear and non-linear receivers are generally ineffective in detecting direct-sequence spread spectrum (DS/SS) signals if the spreading sequences are unavailable. An investigation into using correlation-based processing is reported showing that the cyclostationary property of DS/SS provides detection capability. Finally we describe with results an emerging technique based on higher-order statistics where triple correlation analysis is used, leading to the detection and estimation of DS/SS length and its code generating function g(X).
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HamWeb: Rethinking Packet Radio
by John Hansen, WA0PTV - Abstract: This paper describes a general implementation of a simple "broadcast protocol" useful for terrestrial amateur packet links. It allows the transfer of files and entire directory structures from a server to many client stations simultaneously. Consideration is also given to applications of HTML to amateur packet links.
- Wireless in Ulaan Bataar
by Dewayne Hendricks, WA8DZP - Introduction: In Ulaan Baatar, Mongolian, severe weather conditions prevail, the wired telecommunications infrastructure is very poor, advanced telecommunications technology expertise is limited (although there is considerable local computer expertise), and US access to Mongolian scientific and research facilities is highly constrained by lack of normal Internet connections. Last year, some of us went to Mongolia to integrate a series of data radios into a wireless network, and then field-test them. Our purpose was to build on and apply knowledge being gained from the "Wireless Field Test (WFT) Project for Education," funded by the National Science Foundation (NSF) and run by Dave Hughes of Old Colorado City Communications, in Colorado Springs, CO.
- Management of TNCs by Means of the Simple Network Management Protocol
by H. Hmida, VA2HLH, and M. Barbeau, VE2BPM - Abstract: This article deals with the application of a network management framework, called Simple Network Management Protocol (SNMP), to manage a particular type of network devices named Terminal Node Controllers (TNC). TNCs are widely used in the amateur packet radio community. We present new tools based on SNMP for remote management of TNCs. A Management Information Base (MIB) has been created for the TNCs parameters we manage in KISS mode. The MIB is implemented under the Linux operating system and uses the CMU-SNMP package. We implemented also a new command to manage simultaneously and remotely several TNC parameters.
- North American Digital Systems Directory (NADSD)
by Greg Jones, WD5IVD and Carl Estey, WA0CQG - Abstract: Have you ever wanted to know if there might be a Packet BBS in a distant city where a friend lives ? Or what the frequency is of the PacketCluster station in your area ? Many times it isn't easy to find out about digital services in a distant area. In the past, one way to get this information was to consult the packet listings in the ARRL Repeater Directory. That's now a thing of the past. The North American Digital Systems Directory (NADSD)project was begun in January of 1997 to make information concerning amateur radio digital systems available to amateur radio operators. This paper will describe the history, purpose, and functions of the NADSD.
- TAPR Status Report on Spread Spectrum Activity in the Amateur Radio Service
by Greg Jones, WD5IVD and Dewayne Hendricks, WA8DZP - Abstract: This papers review the current status of Spread Spectrum (SS) in the Amateur Radio Service and also covers TAPR's activity on Spread Spectrum issues over the last two years.
- TCP Header Compression According to Van Jacobson via AX.25
by Gunther Jost, DK7WJ/K7WJ - Abstract: The Van Jacobsen scheme for TCP/IP header compression is briefly introduced, and an implementation of the system under FlexNet is described and discussed.
- TCP/IP on FlexNet -- Just Another Layer
by Gunther Jost, DK7WJ/K7WJ - Abstract: The goals and outcome of a project to optimize TCP/IP transport over the FlexNet AX.25 network is described. A number of optimizations, and their implementations are described and discussed. These include header compression, resend minimization, packet age tracking and ACK consolidation, as well as platform considerations and potential uses.
- An Amateur 900Mhz
Spread-Spectrum Radio Design
by Tom McDermott, N5EG, Bob Stricklin, N5BRG, and Bill Reed, WD0ETZ - Abstract: System design principles and high-level design details are described for a new spread-spectrum radio design for the 900Mhz amateur band. The radio is designed to provide A 10-BASE-T interface as the data port, and is designed to provide transport of IP-based data. It is planned to provide both stand-alone and fully-networked hub configurations. The design is based on Frequency-Hopped Spread Spectrum (FHSS) spreading. Use of Forward Error Correction (FEC) and QPSK modulation provide significant system gain performance compared to other FHSS FSK designs. The radio is currently in the printed-circuit board layout stage.
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VHF/UHF/Microwave Radio Propagation: A Primer for Digital Experimenters
by Barry McLarnon, VE3JF - Abstract: This paper attempts to provide some insight into the nature of radio propagation in that part of the spectrum (upper VHF to microwave) used by experimenters for high-speed digital transmission. It begins with the basics of free space path loss calculations, and then considers the effects of refraction, diffraction and reflections on the path loss of Line of Sight (LOS) links. The nature of non-LOS radio links is then examined, and propagation effects other than path loss which are important in digital transmission are also described.
- Software Radio Technology Overview and Recent Progress
by Joseph Mitola, III - Abstract: This paper summarizes software radio technology emphasizing recent progress, including the first software radio workshop of the European Community and progress of the MMITS (open architecture software radio) Forum. The software radio is an emerging technology for rapidly building flexible, modular, multiband multimode radio systems. It allows one to create radio infrastructure that can be programmed for new standards and dynamically updated with new software personalities. These personalities include air interfaces that may be downloaded to software radios "over the air", reducing the need to purchase new hardware for new services. The technology has been proven in the field, but there are technical, economic and institutional challenges remaining before the benefits of this technology are fully available at low cost. This paper highlights key technical challenges and opportunities.
- PerlAPRS: An Automated Control Application for APRS Networks
by Richard Parry, W9IF - Abstract: PerlAPRS is an application which can monitor both local TNC received APRS packets and remote Internet APRS packets and perform an automated action based on criteria specified by the user. The criteria that PerlAPRS uses is the callsign of the station and its location specified as a Maidenhead Grid Square. Other requirements specified by the user increase functionality of the program in real world applications. The actions executed can be written in any language, but UNIX style shell scripts are ideally suited for this purpose. Scripts can be developed to perform functions such as automatic notification via email as well as logging. PerlAPRS is freely distributed under the GNU licensing agreement.
- Update on Digital Voice Technologies
by Paul L. Rinaldo, W4RI - Introduction: At the 1996 Digital Communications Conference, I presented a paper on "Amateur Radio Digital Voice Communications" with the intent of promoting interest among amateur experimenters. Not much progress has been made in developing amateur digital voice systems during the past year. Industry is still doing developmental work but standards are not easily achieved.
- Using a PC and a Soundcard for Popular Amateur Digital Modes
by Thomas M. Sailer, HB9JNX/AE4WA - Abstract: Recently, standard personal computers (PCs) have become powerful enough to do serious digital signal processing (DSP) without the need for a specialized DSP coprocessor. A standard PC soundcard serves as the interface between the analog world of the radio and the digital world of the PC processor. This equipment together with an appropriate software package allows the ham to operate many popular digital modes without a TNC.
- Terminal Node Controllers -- Towards The Next Generation ?
by Darryl Smith, VK2TDS - Abstract: This paper describes work into a new generation of hardware for Terminal Node Controllers (TNC's). This development has been done under Linux on IBM compatible hardware, but is easily transferable to a more traditional microprocessor based TNC design.
- On-Air Measurements of CLOVER P38 Throughput
by Ken Wickwire, KB1JY, Mike Bernock, KB1PZ, and Bob Levreault, W1IMM - Concluding Remarks: This paper is part of a series treating on-air measurement of throughput of various HF data-transmission protocols available to amateurs. Here we describe an extensive set of measurements of throughput for text and other files sent using the file transfer protocols implemented in the HAL P38-CLOVER terminal and firmware package. The files were transmitted over near-vertical-incidence-skywave (NVIS) and one-hop skywave (OHS) paths. The measured throughput data in our experiments were analyzed using software specially written to compute throughput statistics from our CLOVER data. Throughput statistics for compressed and uncompressed text, data, graphics and hybrid (Word and Excel) files are presented, and text throughput is compared with throughput using PacTOR and GTOR.
