Abstract: A distributed active transformer (DAT) based millimeter-wave (MMW) power amplifier circuit is designed for power amplification of MMW frequency signals. The proposed MMW power amplifier circuit is characterized by distributing the input frequency signals into two sets of differential signals and by the use of a distributed active transformer circuit unit to process these two sets of differential signals to thereby generate an amplified frequency signal as the end result of output. The invention provides higher and greater added values and power added efficiency (PAE) and is ideal for use in millimeter-wave communications systems with an operation frequency around 60 GHz.

Abstract: A modular setting diamond jewelry includes a noble metal base with the bottom thereof being in a shape of taper. A plurality of diamond holes is defined in the top of the noble metal base for receiving diamonds therein. A protrusion is formed between each two adjacent diamond holes which locate at the circumference of noble metal base. The peripheral setting diamonds abut against the central diamond with inner edges thereof. The outer edge of each peripheral diamond is aligned to the peripheral edge of the noble metal base. One diamond hole is defined in the center of the noble metal base, and eight diamond holes are defined around the central diamond hole.

Abstract: A modular setting diamond jewelry includes a noble metal base with the bottom thereof being in a shape of taper. A plurality of diamond holes is defined in the top of the noble metal base for receiving diamonds therein. A protrusion is formed between each two adjacent diamond holes which locate at the circumference of noble metal base. The peripheral setting diamonds overlap against the central diamond with inner edges thereof. The outer edge of each peripheral diamond is aligned to the peripheral edge of the noble metal base. One diamond hole is defined in the center of the noble metal base, and eight diamond holes are defined around the central diamond hole.

Abstract: A microwave or millimeter-wave balun is provided. The balun uses three edge-coupled lines along with a plurality of air bridges instead of two edge-coupled lines used in a conventional planar Marchand balun. The first edge-coupled line and the second edge-coupled line are substantially parallel, and the third edge-coupled line is disposed also substantially in parallel between the first edge-coupled line and the second edge-coupled line. The plurality of air bridges are transmission lines between the first edge-coupled line and the second edge-coupled line. The air bridges have total width longer than one half of the total length of the first edge-coupled line or the second edge-coupled line. By combining three edge-coupled-lines and a plurality of air bridges, the Marchand balun has a higher coupling coefficient and increases the operation bandwidth. The microwave monolithic integrated circuit (MMIC) mixer based on the balun can provide compact size compared to conventional ones.

Abstract: A filter device with transmission zeros is provided according to the present invention, which has an odd mode resonant frequency and an even mode resonant frequency. The filter device includes: a substrate, a metallic rectangular ring, a signal couple-in/couple-out module, and a metallic ground plane, wherein the surface of said metallic ground plane is parallel to the plane enclosed by said metallic rectangular ring, and said metallic rectangular ring applied to the filter device of the present invention has a perimeter shorter than or equal to the wavelength corresponding to the mean of said odd mode resonant frequency and said even mode resonant frequency, thereby allowing said filter device of the present invention, in a situation of specific bandpass frequency, to reduce its perimeter to about half of the perimeter of conventional annular rectangular dual mode filters.

Abstract: A modular setting diamond jewelry includes a noble metal base with the bottom thereof being in a shape of taper. A plurality of diamond holes is defined in the top of the noble metal base for receiving diamonds therein. A protrusion is formed between each two adjacent diamond holes which locate at the circumference of noble metal base. The peripheral setting diamonds abut against the central diamond with inner edges thereof. The outer edge of each peripheral diamond is aligned to the peripheral edge of the noble metal base. One diamond hole is defined in the center of the noble metal base, and eight diamond holes are defined around the central diamond hole.

Abstract: A ring millimeter-wave filter is a three-dimensional dual-mode ring filter. The ring millimeter-wave filter makes use of a three-dimensional coupling architecture as the feed of a filter to conquer the limit of the smallest spacing of a planar circuit made by the low-temperature cofired ceramic (LTCC) process so as to achieve the required coupling. Moreover, through the design of an embedded microstrip line, more than 20% of the filter area can be saved to facilitate integration with other components.

Abstract: A ring millimeter-wave filter is a three-dimensional dual-mode ring filter. The ring millimeter-wave filter makes use of a three-dimensional coupling architecture as the feed of a filter to conquer the limit of the smallest spacing of a planar circuit made by the low-temperature cofired ceramic (LTCC) process so as to achieve the required coupling. Moreover, through the design of an embedded microstrip line, more than 20% of the filter area can be saved to facilitate integration with other components.

Abstract: A three-dimensional balun is disclosed by laminating alternate layers of conductor and dielectric substrate on top of each other to create a microwave circuit. The laminated layers are constructed in a transmission line configuration, corresponding to an equivalent circuit, wherein the first and third transmission lines, the fifth and seventh transmission lines, the second and fourth transmission lines, and the sixth and eighth transmission lines are pairs of coupling lines; one end of the sixth transmission line is defined as an input; one end of the seventh transmission line is defined as a first output; one end of the eighth transmission line is defined as a second output. When signals close to the center frequency of the operating balun are input from the unbalanced side, the signals are converted and then output through the first and second outputs having the same amplitude and producing 180-degree phase shifts.

Abstract: A three-dimensional balun is disclosed by laminating alternate layers of conductor and dielectric substrate on top of each other to create a microwave circuit. The laminated layers are constructed in a transmission line configuration, corresponding to an equivalent circuit, wherein the first and third transmission lines, the fifth and seventh transmission lines, the second and fourth transmission lines, and the sixth and eighth transmission lines are pairs of coupling lines; one end of the sixth transmission line is defined as an input; one end of the seventh transmission line is defined as a first output; one end of the eighth transmission line is defined as a second output. When signals close to the center frequency of the operating balun are input from the unbalanced side, the signals are converted and then output through the first and second outputs having the same amplitude and producing 180-degree phase shifts.

Abstract: An instrument for evaluating fluorescence of a heterogeneous tissue includes means for exciting a two-dimensional portion of the tissue surface with excitation radiation at a plurality of excitation wavelengths, means for collecting emission radiation from the two-dimensional portion of the tissue surface simultaneously with excitation of the portion, and means for forming a two-dimensional excitation-emission map of the excitation radiation and the simultaneously collected emission radiation and spatially averaging the excitation and emission radiation.