Gehrmann, ElkeElkeGehrmannJacob, ArneArneJacobBirtel, PhilipPhilipBirtelDürr, WolfgangWolfgangDürr2021-01-062021-01-062012-083rd ITG International Vacuum Electronics Workshop 2012http://hdl.handle.net/11420/8305enTechnology::600: TechnologyFilter Helices for Traveling Wave TubesConference Paper