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Progress In Electromagnetics Research C
ISSN: 1937-8718
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NEW METHOD OF INTEGRATING PERIODIC PERMANENT MAGNET (PPM) ASSEMBLY IN TRAVELING WAVE TUBES (TWTS)

By T. Mulcahy, H. Song, and F. Francisco

Full Article PDF (582 KB)

Abstract:
In traveling wave tube (TWT) amplifiers, an axial focusing magnetic field is required to keep electrons traveling in a narrow, pencil-like beam over the considerable length of the circuit. Conventionally, this focusing has been accomplished by using a periodic permanent magnet system housing axially polarized ring magnets. Making the structure to this point has been a complicated process consisting of brazing multiple metals together and honing the piece to the desired specifications. We present a new method of fabricating this housing structure monolithically using iron, developing magnetically oversaturated housing regions, and saving processing time and effort.

Citation:
T. Mulcahy, H. Song, and F. Francisco, "New Method of Integrating Periodic Permanent Magnet (Ppm) Assembly in Traveling Wave Tubes (TWTs )," Progress In Electromagnetics Research C, Vol. 10, 187-199, 2009.
doi:10.2528/PIERC09082907

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