Four-step digital p¿i¿n diode phase shifter in waveguide at C band using two diodes

The purpose of the work was to design a 2 bit reflection-type phase shifter which could be manufactured by a cheap mass-production technique and which utilised two, rather than the usual three, p¿i¿n diodes. Since these diodes comprise a relatively large fraction of the total cost of the phase shifter, the saving of one diode allows a useful reduction in cost. The phase shifter, which is in reduced-height waveguide and covers the 5275¿5475 MHz band, allows the phase of a signal reflected from it to be changed by 90°, 180° and 270°. The letter describes the design and performance of the phase shifter. The phased-array configuration for which it would be appropriate is a large reflect array with, say, 2000 elements.