Fujitsu Corporation

Hideki Ikuta

Masahiro Hayakawa

Shin Watanabe

Yutaka Hirano

Ichiro Abeno

Hideo Ashida

Tominaga Watanabe

A high-performance low-cost functional module package handles microwaves or millimeter waves. The package has multilayered dielectric substrates, signal through holes (25, 28) connected to signal conductors that are formed on one of the dielectric substrates, and ground through holes (24, 26, 27, 29) connected to ground conductors that are formed on another of the dielectric substrates. The through holes are formed on side faces of the dielectric substrates and serve as terminals. Each pair of the ground through holes (24 and 26, or 27 and 29) is arranged on opposite sides of a corresponding one (25 or 28) of the signal through holes. The terminals are positioned between parts of the package to be connected to an external circuit board and the signal and ground conductors.

Microwave/millimeter-wave functional module package

A phase modulator having a Gilbert cell mixer can be used in frequency ranges from a microwave frequency band of several GHz to a millimeter wave band of several 10 GHz. Two output signals Vout1, Vout2 from the Gilbert cell mixer are supplied to balanced input terminals of a balanced-to-unbalanced converter, which produces a phase-modulated output signal Vout from an unbalanced output terminal thereof. Even when a differential amplifier comprising FETs Q1, Q3 and a differential amplifier comprising FETs Q2, Q4 do not operate symmetrically, the phase modulator generates phase-modulated output signals that have the same amplitude as each other and are in opposite phase to each other. With the Gilbert cell mixer comprising FETs, the phase modulator can be used in the frequency ranges described above. If the balanced-to-unbalanced converter is in the form of a planar circuit, then the phase modulator may be implemented by an MMIC.

Gilbert cell phase modulator having two outputs combined in a balun

A capacitor for use in microwave transistor, comprises a dielectric material layer and conductive layers covering both sides of the surfaces of the dielectric material layer. A plurality of points on the surface of one of the conductive layers are connected by conduction wires. Each of the conductive wires has a length less than .lambda..sub.0 /2.sqroot..epsilon..sub.r, where .lambda..sub.0 is the minimum wavelength of electric signals applied to the capacitor element, and .epsilon..sub.r is the dielectric constant of the dielectric material layer. The middle portion of each of the conductive lines is separated from the above-mentioned one of the conductive layers. The conductive wires prevent the capacitor element from becoming extremely inductive even when the frequency is high.

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Kawasaki, Japan

Hideki Ikuta