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Dielectric Quarter-wave and Half-wave Plates in Circular Waveguide

R. M. Brown

出版	Defense Technical Information Center, 1953
URL	http://books.google.com.hk/books?id=W1-6NwAACAAJ&hl=&source=gbs_api

註釋

An experimental program at NRL has led to the design of quarter-wave and half-wave plates in X-band circular waveguide. The plates are polystyrene slabs, tapered to reduce reflections, and are mounted in a diametral plane of the waveguide. Quarter-wave plates having differential phase shifts of between 88 deg and 92 deg from 8750 to 9700 Mc were built. A half-wave plate having a phase shift of between 176 deg and 186 deg from 8200 to 10,000 Mc was built. The VSWR'S of the plates were less than 1.2 in these frequency ranges. Several rotary phase shifters using these plates found to deviate from linearity by less than 0.5 deg at 9375 Mc. The effect of imperfect plates on the performance of the rotary phase shifter, the calibration of the rotary phase shifter, and the errors caused by slightly noncircular waveguide are discussed in the appendixes.