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This paper describes the development, along with detailed phase-noise analysis, of V-band monolithic-microwave integrated-circuit (MMIC) dielectric-resonator oscillators (DROs) achieving state-of-the-art performances. A T[E.sub.01[delta]]-mode Ba(Mg,Ta)[O.sub.3] cylindrical dielectric resonator (DR) is directly placed on a MMIC GaAs substrate to avoid the loss and uncertainty of bonding wires. A 0.15-[micro]m AlGaAs-InGaAs heterojunction field-effect transistor with optimized structure is developed as an active device. A design procedure proposed by the authors is employed, which allows us to analyze and optimize circuits in consideration for the output power, phase noise, and temperature stability. A developed DRO co-integrated with a buffer amplifier exhibits a low phase noise of -90 dBc/Hz at 100-kHz offset, a high output power of 10.0 dBm, and an excellent frequency stability of 1.6 ppm/[degrees]C at an oscillation frequency of 59.6 GHz, all of which are state-of-the-art performances reported for MMIC DROs above V-band. An experimental and theoretical analysis for the phase-noise-reduction effect of a DR is also addressed. Index Terms--Dielectric resonator oscillators (DROs), dielectric resonators (DRs), field-effect transistors (FETs), millimeter wave, monolithic microwave integrated circuits (MMICs), oscillators.

This paper describes a systematic approach to the design and analysis for dielectric resonator oscillators (DROs). The approach features a temperature- and structural-parameters-independent dielectric resonator (DR) model and a newly developed temperature-dependent nonlinear FET model. The implementation of these models on a harmonic-balance circuit simulator allows prediction for mechanical tuning characteristics, coupling strength dependencies, and temperature-dependent performance of oscillation frequency, output power, and phase noise of DROs. V-band heterojunction FET monolithic-microwave integrated-circuit DROs utilizing a [TE.sub.01[sigma]]-mode cylindrical DR were designed and fabricated based on the proposed procedure. Good agreement between the predicted and measured characteristics indicates the validity of our design technique featuring the proposed DR and FET models. Index Terms--Dielectric resonator oscillators (DROs), dielectric resonators (DRs), FETs, millimeter wave, monolithic microwave integrated circuits (MMICs), oscillators, temperature.

Compact dc-60-GHz heterojunction field-effect transistor (HJFET) monolithic-microwave integrated-circuit (MMIC) switches have been demonstrated for millimeter-wave communications and radar systems. To reduce the MMIC chip size, a novel ohmic electrode-sharing technology (OEST) has been developed for MMIC switches with series - shunt FET configuration. Four FET's of the series-shunt single-pole double-throw (SPDT) MMIC switch were integrated into an area of approximately 0.018 [mm.sup.2]. The developed MMIC switches have a high power-handling capability with low insertion loss (IL) and high isolation (Iso) at millimeter-wave frequencies. From dc to 60 GHz, the single-pole single-throw (SPST) MMIC switch achieved the IL and Iso of better than 1.64 and 20.6 dB, respectively. At 40 GHz, the IL increases by 1 dB at the input power of 21 dBm. A novel large-signal FET model for the switch circuit is presented. The simulated power.transfer performance shows the excellent agreement with the measured one. The developed MMIC switches will contribute to the low-cost and high-performance millimeter-wave communications and radar systems. Index Terms - FET's, MMIC switches, modeling, nonlinear circuits.

The development of 60 GHz-band ultra-miniature FM/frequency-shift keying (FM/FSK) transmitter/receiver modules fabricated with a complete monolithic-microwave integrated circuits (MMIC) chip set, including dielectrically stabilized fundamental-frequency oscillators for multimedia wireless communication systems, is reported. The 0.9 cc transmitter module, which consists of a voltage controlled oscillator (VCO) and two power amplifiers, exhibits 11.5 MHz/V modulation sensitivity, 10.2 dBm output power, and -2.4 ppm/[degrees] C frequency stability. With the receiver module, which consists of low noise amplifier (LNA), a mixer, and a local oscillator (LO), 5.4 dB double-side band (DSB) noise figure with 10.8 dB downconversion gain has been achieved. The 60 GHz-band monolithic dielectric-resonator (DR) stabilized oscillators offer a practical approach to ultra-miniature transmitter/receiver modules for high-speed wireless LAN systems with data rates greater than 10 Mbps and for video-signal and compressed HDTV-signal (MUSE) transmission systems.

ABSTRACT The aim of this study was to estimate a procedure for the biobased carbon content of polypropylene (PP) resin isolated from composites containing additives or fillers on the basis of the carbon 14 concentration ratio, as measured by accelerated mass spectrometry (AMS). To reliably estimate the biobased carbon content of plastics, additives and fillers in the composites had to be removed because they often contain significant amounts of biobased carbon. To obtain specimens with purity suitable for estimation, an isolation procedure for PP from the composites was devised. The dissolution of the composites in 1,2,3,4-tetrahydronaphthalene at 150°C, followed by immediate centrifugation of the hot solution, yielded PP as semicrystalline precipitates by allowing the hot solution to cool during centrifugation. The recovery of the resin through the scooping off of the precipitates was typically 90%. This simple procedure provided a suitable specimen for the estimation of biobased carbon content by AMS on the basis of ASTM D 6866. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2014, 131, 39978. [ABSTRACT FROM AUTHOR]