In 1991, Joe Mitola independently reinvented the term software radio for a plan to build a GSM base station that would combine Ferdensi's digital receiver with E-Systems Melpar's digitally controlled communications jammers for a true software-based transceiver. E-Systems Melpar sold the software radio idea to the US Air Force. Melpar built a prototype commanders' tactical terminal in 1990–1991 that employed Texas Instruments TMS320C30 processors and Harris Corporation digital receiver chip sets with digitally synthesized transmission. The Melpar prototype didn't last long because when E-Systems ECI Division manufactured the first limited production units, they decided to "throw out those useless C30 boards", replacing them with conventional RF filtering on transmit and receive and reverting to a digital baseband radio instead of the SpeakEasy like IF ADC/DACs of Mitola's prototype. The Air Force would not let Mitola publish the technical details of that prototype, nor would they let Diane Wasserman publish related software life cycle lessons learned because they regarded it as a "USAF competitive advantage". So instead, with USAF permission, in 1991, Mitola described the architecture principles without implementation details in a paper, "Software Radio: Survey, Critical Analysis and Future Directions" which became the first IEEE publication to employ the term in 1992. When Mitola presented the paper at the conference, Bob Prill of GEC Marconi began his presentation following Mitola with: "Joe is absolutely right about the theory of a software radio and we are building one." Prill gave a GEC Marconi paper on PAVE PILLAR, a SpeakEasy precursor. SpeakEasy, the military software radio was formulated by Wayne Bonser, then of Rome Air Development Center (RADC), now Rome Labs; by Alan Margulies of MITRE Rome, NY; and then Lt Beth Kaspar, the original DARPA SpeakEasy project manager and by others at Rome including Don Upmal. Although Mitola's IEEE publications resulted in the largest global footprint for software radio, Mitola privately credits that DoD lab of the 1970s with its leaders Carl, Dave, and John with inventing the digital receiver technology on which he based software radio once it was possible to transmit via software.
in 1991, Joe mitola indepENdeNtly ReiNveNtED tHe tErm softwArE radio FoR a PlaN to buiLd A Gsm Base sTatioN tHaT wOuld combiNe Ferdensi's digital rEcEiver wIth E-systEms melPAR's digiTALly CoNtRolled cOmmUniCatiOns jammERs fOR A trUe SOFTware-baseD traNsceivEr. E-SysTEmS MeLPar SOlD the SoFtwaRe radio idea To tHe Us Air FOrCe. mElPar BuiLt a PrOtotyPE coMmAndErs' tactICaL TerMinal iN 1990–1991 that EmpLOYed teXAS instruments Tms320C30 prOCeSSorS And HarRiS CorPOraTioN digitaL receiveR ChiP setS With diGItALly SyNtHesiZed TRAnsMIssioN. THE meLpar proToType didN't last long BecaUsE when e-systeMs eCI dIvisioN ManUFaCTURed tHe fiRst lImitEd producTion unItS, they decIdeD tO "thrOW Out thoSe usELeSS C30 boaRDs", repLacing thEm wIth ConveNtionAl rF fiLtErinG on tRanSmIt And receive and reveRTINg to a dIgitaL BasebanD raDio insteAd Of tHe sPEAkeaSY likE if adc/Dacs oF mitoLA'S prOtOtypE. THE aIr FORCe WoulD not lEt mItolA pUbLISH the techNIcAl DetaiLs Of thAt Prototype, NoR woUld They lET dIane WassermaN pUBLish reLaTEd SoftWare LIfe cycLe lessons learned because They RegArdeD it AS a "uSaf cOmpetitive advantAge". so instead, wIth usaf PerMissioN, in 1991, miTola DEsCrIbEd tHe architEctuRE PrincipleS wItHouT IMPlemEnTatiON DetAiLS In a PapeR, "sofTwAre raDIo: suRVey, CritiCal analySiS And futuRE DirectioNs" which became The FiRST iEeE pubLICATiON to EMpLoy THe Term IN 1992. wheN MitolA pReseNteD the pAPer At The coNfeRence, BOB PRilL of gec marcONi BegAn hIs pReSeNtatiOn folloWinG MITola WitH: "Joe is aBsolutElY riGht About THe tHeOry of a soFtwAre radiO and WE arE buildiNg onE." PriLL gavE a gEc MARCOni PAper on pave PILlar, a sPEAkeasy precursoR. SPeaKeaSy, the miliTaRy SofTWare RAdIo was Formulated by waYnE BONSer, then of ROme air dEVElOpment center (radc), Now roMe laBs; bY aLan marguLiEs oF mitre rOmE, ny; anD then lt bEth kaspAr, the oRiginaL dArpa sPeAkeasy PRojecT MANager anD bY others at rome inclUdIng don upmAL. alThough MitOla'S ieeE pUbLicaTIonS resuLTeD In thE LaRgEst GlObal FOotpriNt for SOftware radio, Mitola pRIvAtElY credits tHat DOd lAB Of the 1970s wIth itS Leaders caRL, DavE, And jOhn witH inveNtInG the dIgital recEIver tecHnolOGy oN whicH he BaSed Software radIo onCe iT wAs posSiblE TO transMiT via soFTwarE.