Showing papers on "Balun published in 1975"

Series connected stripline balun

Abstract: A stripline-to-two-conductor balun comprising series connected transverse electric magnetic mode (TEM) 90° stripline couplers to transform an unbalanced stripline TEM field to a two wire TEM balanced field. The coupler sections of the balun comprises two overlay parallel conductors deposited on opposite sides of a dielectric layer and includes input stripline circuitry adapted to be connected to the input of one coupler section of the balun. The dielectric layer is disposed between and insulated from two parallel ground plane members. The output conductors are coupled through one ground plane member and are electrically connected respectively to one of an antiphase coupled arm of each series connected coupler section. The other coupled arm of each series connected coupler is terminated in a radio frequency (RF) short circuit, the direct coupled arm of the second coupler section is terminated in an open circuit.

New broadband balun

Abstract: The letter describes a new balun composed of a modified ‘rat race’ with an open-circuit impedance at the uncoupled port. The advantage of this device is the great bandwidth, together with its very small dimensions. The performance of a layout on an alumina substrate is compared with theorotical predictions. For a midband frequency of 2.5 GHz, a bandwidth ratio of 52% and dimensions smaller than 1 cm2 on a 10 mil-thick alumina substrate are typical.