BEGIN:VCALENDAR VERSION:2.0 PRODID:IEEE vTools.Events//EN CALSCALE:GREGORIAN BEGIN:VTIMEZONE TZID:America/New_York BEGIN:DAYLIGHT DTSTART:20220313T030000 TZOFFSETFROM:-0500 TZOFFSETTO:-0400 RRULE:FREQ=YEARLY;BYDAY=2SU;BYMONTH=3 TZNAME:EDT END:DAYLIGHT BEGIN:STANDARD DTSTART:20221106T010000 TZOFFSETFROM:-0400 TZOFFSETTO:-0500 RRULE:FREQ=YEARLY;BYDAY=1SU;BYMONTH=11 TZNAME:EST END:STANDARD END:VTIMEZONE BEGIN:VEVENT DTSTAMP:20221104T212730Z UID:9724CEC4-21ED-41EF-8F3A-138ABCD1AF7F DTSTART;TZID=America/New_York:20221006T130000 DTEND;TZID=America/New_York:20221006T134500 DESCRIPTION:Antennas are a key component for communications\, both for rece iving and transmitting\, and there is a certain fascination with their des ign. It all started with the Hertzian dipole and its understanding and mat hematical treatment. This presentation is based\, in part\, on modern math ematical tools as well as test equipment. As an example\, Hallén wrote hi s famous integral equation to give an exact treatment of antenna current w ave reflection at the end of a tube-shaped cylindrical antenna in 1956\, b ut his first work on this subject probably goes back to 1938.\nThis equati on enabled him to show that on a thin wire\, the current distribution is a pproximately sinusoidal and propagates at nearly the speed of light. For t his treatment\, that is an important contribution We will learn here that by optimizing the effective length of a rod antenna it will become directi onal and will have a radiation pattern that provides gain. Antenna tuning is important for field operation. Dr. Tapan Sarkar\, past IEEE AP-S presid ent\, Dr. Jim Breakall\, Dr. Ajay K. Poddar\, and I met several times in t he past 30 years\, discussed my pet project: positioning of antennas for p ortable operation\, and we had many exchanges on this topic and sunspots a nd their effect on HF propagation. Dr. Tapan Sarkar passed away in 2020\, but his scientific contributions in the field of Antenna and Propagation w ill be helpful to researchers and next-generation students in the field of wireless communication\, especially applications in humanitarian technolo gy. Now\, Sun Cycle 25 is building an increasingly favoring radio operatio n in the HF band (1.5 to 30 MHz). There are military and other radio appli cations for 5 to 20-W battery-operated radios with whip antennas that make the radio portable. A whip antenna has no ground return\, or proper count erpoise so it is not optimized for signal propagation. Thus\, some users d rag a wire behind them. This solution is not ideal. We explore optimizing antenna performance for HF\, VHF\, and UHF (spanning 1.5 to 512 MHz) manpa cks and using an antenna tuning unit (ATU). Battery-operated manpacks with internal ATUs were used for testing\, comparing internal ATUs with the pe rformance obtained using external tuners. The necessary mathematical treat ment for this case is provided here. Prof. Sarkar was involved with the mo deling software WIPL-D and HOBBIES. Some anecdotes will be provided\, with interactions with him on these\, including numerous projects supported by IEEE SIGHT (Special interest Group on Humanitarian Technology) under the leadership of Dr. Ajay Poddar\, Chair IEEE Humnatrain Activity Committee I nter-Society and Region Coordinator\, IEEE AP\, and MTT Societies. Dr. Tap an Sarkar and Dr. Ajay Poddar helped in establishing three IEEE awards for supporting students and young engineers working on Antenna and Microwave Theory and Technology: (1) IEEE Ulrich L. Rohde Innovative Conference Pape r Awards on Antenna Measurements and Applications (This annual cash award and plaque\, are given to the two most innovative conference papers presen ted at the annual topical meeting on Antenna Measurements and Applications )\, (2) IEEE Ulrich L. Rohde Innovative Conference Paper Awards on Computa tional Techniques in Electromagnetics (This annual cash award and plaque\, are given to the two most innovative conference papers presented at the a nnual topical meeting on Computational Techniques in Electromagnetics)\, a nd (3) IEEE IEEE Ulrich L. Rohde Humanitarian Technical Field Project Awar d\, USD 20\,000 project award given annually by IEEE AP Society.\n\nSpeake r(s): Dr.Ulrich L. Rohde\, Dr. James Breakall\n\nBldg: Hanover Manor\, 16 Eagle Rock Avenue \, East Hanover\, Pennsylvania\, United States\, 07936 LOCATION:Bldg: Hanover Manor\, 16 Eagle Rock Avenue \, East Hanover\, Penn sylvania\, United States\, 07936 ORGANIZER:akpoddar@ieee.org SEQUENCE:2 SUMMARY:A look at a novel Antenna design URL;VALUE=URI:https://events.vtools.ieee.org/m/331210 X-ALT-DESC:Description: <br /><p>Antennas are a key component for communica tions\, both for receiving and transmitting\, and there is a certain fasci nation with their design. It all started with the Hertzian dipole and its understanding and mathematical treatment. This presentation is based\, in part\, on modern mathematical tools as well as test equipment. As an examp le\, Hall&eacute\;n wrote his famous integral equation to give an exact tr eatment of antenna current wave reflection at the end of a tube-shaped cyl indrical antenna in 1956\, but his first work on this subject probably goe s back to 1938.&nbsp\;<br />This equation enabled him to show that on a th in wire\, the current distribution is approximately sinusoidal and propaga tes at nearly the speed of light. For this treatment\, that is an importan t contribution We will learn here that by optimizing the effective length of a rod antenna it will become directional and will have a radiation patt ern that provides gain. Antenna tuning is important for field operation. D r. Tapan Sarkar\, past IEEE AP-S president\, Dr. Jim Breakall\, Dr. Ajay K . Poddar\, and I met several times in the past 30 years\, discussed my pet project: positioning of antennas for portable operation\, and we had many exchanges on this topic and sunspots and their effect on HF propagation. Dr. Tapan Sarkar passed away in 2020\, but his scientific contributions in the field of Antenna and Propagation will be helpful to researchers and n ext-generation students in the field of wireless communication\, especiall y applications in humanitarian technology. Now\, Sun Cycle 25 is building an increasingly favoring radio operation in the HF band (1.5 to 30 MHz). T here are military and other radio applications for 5 to 20-W battery-opera ted radios with whip antennas that make the radio portable. A whip antenna has no ground return\, or proper counterpoise so it is not optimized for signal propagation. Thus\, some users drag a wire behind them. This soluti on is not ideal. We explore optimizing antenna performance for HF\, VHF\, and UHF (spanning 1.5 to 512 MHz) manpacks and using an antenna tuning uni t (ATU). Battery-operated manpacks with internal ATUs were used for testin g\, comparing internal ATUs with the performance obtained using external t uners. The necessary mathematical treatment for this case is provided here . Prof. Sarkar was involved with the modeling software WIPL-D and HOBBIES. Some anecdotes will be provided\, with interactions with him on these\, i ncluding numerous projects supported by IEEE SIGHT (Special interest Group on Humanitarian Technology) under the leadership of Dr. Ajay Poddar\, Cha ir IEEE Humnatrain Activity Committee Inter-Society and Region Coordinator \, IEEE AP\, and MTT Societies. Dr. Tapan Sarkar and Dr. Ajay Poddar helpe d in establishing three IEEE awards for supporting students and young engi neers working on Antenna and Microwave Theory and Technology: (1) IEEE Ulr ich L. Rohde Innovative Conference Paper Awards on Antenna Measurements an d Applications (This annual cash award and plaque\, are given to the two m ost innovative conference papers presented at the annual topical meeting o n Antenna Measurements and Applications)\, (2) IEEE Ulrich L. Rohde Innova tive Conference Paper Awards on Computational Techniques in Electromagneti cs (This annual cash award and plaque\, are given to the two most innovati ve conference papers presented at the annual topical meeting on Computatio nal Techniques in Electromagnetics)\, and (3) IEEE IEEE Ulrich L. Rohde Hu manitarian Technical Field Project Award\, USD 20\,000 project award given annually by IEEE AP Society.&nbsp\;</p> END:VEVENT END:VCALENDAR