b'Engineer Innovation | Aerospace Siemens brings its expertize to solve the complex challenge of generating an homogenous sound field around the test item.Christophe Fabris Project LeaderAntenna Mechanical Analysis Thales Alenia SpaceIn 2016, the National Aeronautics andobtain the target overall sound Space Agency (NASA) published thepressure level (OASPL). The vibration NASA Handbook 7010, which is thelevels measured on the specimen first handbook that lays out theduring the DFAX test are comparable guidelines for companies wanting towith those measured with reverberant use the new acoustic testingfield acoustic excitation. In the near methodology. Like their Northfuture, satellites that are placed on the American counterparts, leadingEuropean launch pad of Kourou might European industry companies such ashave been partially qualified using rock Thales Alenia Space are conductingconcert loudspeakers.experiments to explore and validate new methods for satellite acousticClearly, DFAX lowers overall test testing. expenses, and can be performed (nearly) everywhere bringing more Pump up the volume flexibility with shorter test sequences. What do Werchter, Belgium; Roskilde,However, safety, reliability and Denmark; and Kourou, French Guyanaaccuracy of the tests should not be have in common? Werchter anddiscounted. The nature of the sound Roskilde are locations of popularfield in a DFAX test differs from that of open-air rock and pop festivals thata reverberant room test. This bring crowds of passionate musicdifference needs to be accounted for in lovers together. Incidentally, in recentorder to produce realistic test years, performances of modernconditions. The engineers of Thales loudspeakers and amplifiers have beenAlenia Space are relentlessly working pushed to their maximum to betterto improve and validate the DFAX entertain the ever-growing hordes ofmethod.music fans. The availability of commercial loudspeakers andHomogenate the sound fieldamplifiers capable of generating theThe engineering team at Thales Alenia sound field required in a test has madeSpace in Toulouse, France, develop the development of the direct fieldsatellite components that will later be acoustic excitation method possible. Inintegrated in to the full system. The a DFAX test, the specimen is placed incompany owns an acoustic reverberant the middle of a loudspeaker circle androom facility; however, this facility is gets excited by a direct acoustic field.located in Cannes, some 500km from Modern loudspeakers and amplifiersToulouse. In practice, this implies that deliver the required high decibels toevery newly developed component 14'