Showing papers on "Balun published in 1977"

Broadband high frequency baluns and mixer

Abstract: A double slot balun has two pairs of coplanar, electric conductive sheets in a superposed, spaced, electrically insulated relation on opposite planar surfaces of a dielectric substrate forming two slots disposed in spaced, parallel planes. Unbalanced signals applied simultaneously to common ends of the slots result in balanced in-phase signals at the opposite end of the two slots. A constant impedance balun has two alined, electric conductive strips in a superposed, spaced, electrically insulated relation mounted on opposite planar surfaces of a dielectric substrate with the widths at opposite ends of each conductive strip being chosen for selected parallel-plate impedance characteristics and one conductive strip having a selected taper, preferably following a cosine curve, while the width of the other conductive strip is selected relative to the cosine taper along its length to provide a constant impedance at any point along the length of the two conductive strips. A broadband mixer has a common dielectric substrate with a double slot balun associated with an RF signal port and two of the constant impedance baluns associated with the LO signal port and in turn these baluns are interconnected with a double balanced bridge arrangement having two separate rings of matched diodes with no cross-over connections between the baluns or between the baluns and the diodes.

Optimim design for a broadband microstrip balun

Abstract: The letter reports calculations of Marchand balun performance which show that bandwidths approaching 50:1 (for a V.S.W.I.?2:1) should be achievable with overlaid microstrip structures. The bandwidth limits (?8:1) reported by previous writers appear to reflect only the inaccessibility of the true optimum to the semiempirical design methods used and the limitations of fabrication on single-thickness card. Preliminary experimental results confirm the theoretical indications.

Signal converter using a quad diode race

Abstract: A signal converter, and more particularly, a mixer includes a quad diode race or bridge having a first signal supplied to a first pair of input ports in a balanced state, and a second signal supplied to another pair of input ports in an unbalanced state. The unbalanced connection to the diode race is effected via connections to conducting strips of a printed circuit board, and the balanced connection is effected by a hybrid balun element. The output from the circuit is derived from an input to the balun, at a low signal level.