{"71187":{"#nid":"71187","#data":{"type":"news","title":"GTRI Receives $4 Million to Redesign Air Traffic Control Radios","body":[{"value":"\u003Cp\u003EThe Georgia Tech Research Institute (GTRI) has received a $4 million contract from the U.S. Air Force to redesign critical modules used in thousands of air traffic control radios.  First fielded in 1968, these ground-based units play a vital role in keeping U.S. military aircraft safe, and the redesign should help keep the radios on the job until newer designs can replace them.\u003C\/p\u003E\n\u003Cp\u003EThe redesign task - which must be completed in a year - is both challenging and important, said Russell S. McCrory, a GTRI senior research engineer.  Some 7,500 of these ground communications radios - known as AN\/GRT-21 and AN\/GRT-22 transmitters and AN\/GRR-23 and AN\/GRR-24 receivers - are still in service. When they break down, they often require parts that are no longer available.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022This system has been in the field almost 40 years now,\u0022 said McCrory, who is project director.  \u0022Many parts now unavailable were originally manufactured by hand, and would be very expensive to reproduce today just because of the manual labor involved.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EAmong other things, GTRI engineers must find ways to replace numerous semiconductor components, such as transistors and diodes that are no longer manufactured.  In some cases the original makers are no longer in business; in other cases the products are so old that no replacements are available.\n\u003C\/p\u003E\n\u003Cp\u003EInstead of trying to reproduce the original technology, GTRI engineers are designing replacement units that use only modern off-the-shelf parts.  The aim is to give the customer a replacement module that is plug-compatible with the original unit and does the same job.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022We throw away the original design, and we make a unit with the same size and the same function,\u0022 McCrory said. \u0022If the old unit had a certain meter reading to show a certain condition, the new one should work identically.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EThe current $4.05 million contract covers redesign of five major assemblies within the GRT\/GRR, a complex system of receivers and transmitters that operates in the VHF and UHF radio-frequency bands.  The five assemblies include a dual-band power amplifier unit, an intermediate-frequency (IF) amplifier, a mixer-multiplier, a power supply unit and a synthesizer.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022This work provides both a technical challenge and a demonstration of GTRI\u0027s commitment to deliver on fast-reaction contracts,\u0022 McCrory said. \u0022Within 12 months, GTRI will produce five complete new designs including all data necessary for the government to obtain competitive bids from manufacturers, engineer prototypes, obtain the initial devices from an outside vendor and update user and operator manuals.\u0022\n\u003C\/p\u003E\n\u003Cp\u003EHe said that GTRI\u0027s changes to the dual-band power amplifier will retain that assembly\u0027s unusual capacity to broadcast a 10-watt radio signal in either the VHF or UHF bands.  \n\u003C\/p\u003E\n\u003Cp\u003EIn addition, the new design will re-engineer the mixer multiplier - a unit that converts received frequencies to a range that can be processed by the receiver - and also modify the IF (intermediate frequency) amplifier in the receiver, which amplifies the received radio signals. And a new power supply will increase reliability.\n\u003C\/p\u003E\n\u003Cp\u003EIn replacing the current radio\u0027s original analog components, GTRI engineers are crafting a system that is still all-analog but uses new off-the-shelf technology that is widely available. This approach allows the Air Force to ask for competitive bids from numerous manufacturers rather than relying on a sole source.\n\u003C\/p\u003E\n\u003Cp\u003EThe savings can be substantial, McCrory said. He cites a competing approach that would have cost the government about $500,000 for drawings of one obsolete transistor in the GRT system, and then another $500,000 for the first transistor reproduced from those drawings.\n\u003C\/p\u003E\n\u003Cp\u003E\u0022Our approach will result in major savings for the military versus trying to remanufacture the original components,\u0022 he said.\n\u003C\/p\u003E\n\u003Cp\u003EGTRI\u0027s role in maintaining the GRT\/GRR radios has evolved over several years. In 1999 the Warner Robins Air Logistics Center at Georgia\u0027s Robins Air Force Base took over engineering responsibility for the radios, and in 2005 GTRI engineers were asked to produce GRT\/GRR technical documentation.\n\u003C\/p\u003E\n\u003Cp\u003ESubsequently, GTRI created a support roadmap for sustaining the units until they are retired, and the analysis showed that major radio components needed to be replaced to meet this goal. \n\u003C\/p\u003E\n\u003Cp\u003EMcCrory adds that his team has made extensive use of GTRI\u0027s SUSTAIN software in helping to identify modules requiring redesign and to justify funding requests. SUSTAIN is a multi-part management tool that helps guide maintenance\/sustainment decisions on older military systems. \n\u003C\/p\u003E\n\u003Cp\u003EEventually, McCrory explains, all Department of Defense radios are due to be replaced by a reprogrammable, software-based technology known as the Joint Tactical Radio System (JTRS).  Though the first JTRS systems could begin replacing high-priority radios as early as 2011, ground radios like the GRT\/GRR systems are scheduled for replacement much later - probably not until 2020 to 2025.  That means GRT\/GRR radios could require maintenance for another 18 years.  \n\u003C\/p\u003E\n\u003Cp\u003EGTRI expects its redesign to help ease the Air Force\u0027s parts inventory and logistics tasks for these radios. The new dual-band-power amplifier is expected to replace three older models, and the new mixer multiplier will replace two older models.  \n\u003C\/p\u003E\n\u003Cp\u003EOne of GTRI\u0027s top goals, McCrory said, is to make it cheaper for the Air Force to simply plug in a new module than to repair an old one.  That would not only save money and time, but also bring broken units back online faster.\n\u003C\/p\u003E\n\u003Cp\u003E\u0027The Air Force, in conjunction with Tobyhanna Army Depot which does the maintenance, has done just a wonderful job keeping this system in the field,\u0022 McCrory said. \u0022We\u0027re trying to help them continue to do that, while keeping costs under control.\u0022 \n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EResearch News \u0026amp; Publications Office\u003Cbr \/\u003E\nGeorgia Institute of Technology\u003Cbr \/\u003E\n75 Fifth Street, N.W., Suite 100\u003Cbr \/\u003E\nAtlanta, Georgia  30308  USA\u003C\/strong\u003E\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EMedia Relations Contacts\u003C\/strong\u003E: John Toon (404-894-6986); E-mail: (\u003Ca href=\u0022mailto:jtoon@gatech.edu\u0022\u003Ejtoon@gatech.edu\u003C\/a\u003E); Kirk Englehardt (404-407-7280); E-mail: (\u003Ca href=\u0022mailto:kirk.englehardt@gtri.gatech.edu\u0022\u003Ekirk.englehardt@gtri.gatech.edu\u003C\/a\u003E) or Abby Vogel (404-385-3364); E-mail: (\u003Ca href=\u0022mailto:avogel@gatech.edu\u0022\u003Eavogel@gatech.edu\u003C\/a\u003E).\n\u003C\/p\u003E\n\u003Cp\u003E\u003Cstrong\u003EWriter\u003C\/strong\u003E: Rick Robinson\n\u003C\/p\u003E","summary":null,"format":"limited_html"}],"field_subtitle":[{"value":"Work will allow vintage devices for continue operating"}],"field_summary":[{"value":"The Georgia Tech Research Institute (GTRI) has received a $4 million contract from the U.S. Air Force to redesign critical modules used in thousands of military air traffic control radios.  The work will extend the life of these radios, which were first fielded in 1968.","format":"limited_html"}],"field_summary_sentence":[{"value":"Redesign work will extend the life of military air traffic radio"}],"uid":"27303","created_gmt":"2008-06-16 00:00:00","changed_gmt":"2016-10-08 03:03:19","author":"John Toon","boilerplate_text":"","field_publication":"","field_article_url":"","dateline":{"date":"2008-06-16T00:00:00-04:00","iso_date":"2008-06-16T00:00:00-04:00","tz":"America\/New_York"},"extras":[],"hg_media":{"71188":{"id":"71188","type":"image","title":"Air traffic control radios","body":null,"created":"1449177358","gmt_created":"2015-12-03 21:15:58","changed":"1475894630","gmt_changed":"2016-10-08 02:43:50"},"71189":{"id":"71189","type":"image","title":"Air traffic control radios","body":null,"created":"1449177358","gmt_created":"2015-12-03 21:15:58","changed":"1475894630","gmt_changed":"2016-10-08 02:43:50"},"71190":{"id":"71190","type":"image","title":"Air traffic control radios","body":null,"created":"1449177358","gmt_created":"2015-12-03 21:15:58","changed":"1475894630","gmt_changed":"2016-10-08 02:43:50"}},"media_ids":["71188","71189","71190"],"related_links":[{"url":"http:\/\/www.gtri.gatech.edu\/","title":"Georgia Tech Research Institute"}],"groups":[{"id":"1188","name":"Research Horizons"}],"categories":[{"id":"136","name":"Aerospace"},{"id":"145","name":"Engineering"},{"id":"147","name":"Military Technology"},{"id":"135","name":"Research"}],"keywords":[{"id":"7356","name":"air-traffic"},{"id":"7357","name":"module"},{"id":"1265","name":"radio"},{"id":"7355","name":"redesign"}],"core_research_areas":[],"news_room_topics":[],"event_categories":[],"invited_audience":[],"affiliations":[],"classification":[],"areas_of_expertise":[],"news_and_recent_appearances":[],"phone":[],"contact":[{"value":"\u003Cstrong\u003EJohn Toon\u003C\/strong\u003E\u003Cbr \/\u003EResearch News \u0026amp; Publications Office\u003Cbr \/\u003E\u003Ca href=\u0022http:\/\/www.gatech.edu\/contact\/index.html?id=jt7\u0022\u003EContact John Toon\u003C\/a\u003E\u003Cbr \/\u003E\u003Cstrong\u003E404-894-6986\u003C\/strong\u003E","format":"limited_html"}],"email":["jtoon@gatech.edu"],"slides":[],"orientation":[],"userdata":""}}}