Radiation integral areas are localized and reduced based upon the locality of scattering phenomena. In the high frequency, the scattering field is given by the currents, not the entire region, but on the local areas near the scattering centers, such as the stationary phase points and edge diffraction points, due to the cancelling effect of integrand in the radiation integral. The numerical calculation which this locality is implemented into has been proposed for 2-dimensional problems. The scattering field can be approximated by integrating the currents weighted by the adequate function in the local areas whose size and position are determined appropriately. Fresnel zone was previously introduced as the good criterion to determine the local areas, but the determination method was slightly different, depending on the type of scattering centers. The objective of this paper is to advance the Fresnel zone criteria in a 2-dimensional case to the next stage with enhanced generality and applicability. The Fresnel zone number is applied not directly to the actual surface but to the virtual one associated with the modified surface-normal vector satisfying the reflection law. At the same time, the argument in the weighting function is newly defined by the Fresnel zone number instead of the actual distance from the scattering centers. These two revisions bring about the following three advantages; the uniform treatment of various types scattering centers, the smallest area in the localization and applicability to 3-dimensional problems.

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Thin-film 2-arm Archimedean spiral antenna coupled with a bismuth (Bi) microbolometer was fabricated on a fused quartz substrate backed by cupper (Cu) plate reflector. Antenna patterns of the device agreed with the theoretical patterns derived from the imaging force model at 100GHz band. The detected voltages of the antenna exhibited a periodic variation with changing the thickness of the substrate. The maximum and minimum detected voltages were obtained when the substrate thickness was odd and even integer multiples of a quarter of the wavelength in the substrate, respectively. Furthermore, the detected voltages were almost constant within the change of ∼3dB ranging from 76.9 to 106.8GHz. The wide band characteristic of the antenna was obtained.

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This paper presents the evaluation of the L-2L de-embedding method with misalignment of the contact position. The issues of misalignment of the contact position are investigated. The analysis of misalignment in the L-2L de-embedding procedure is performed. Two comparisons are carried out to verify the error of the L-2L de-embedding method. The calculation percent error in quality factor of the transmission line becomes up to 9.0%, while the transistor S-parameter error percentage becomes up to 21% at 60GHz in the experimental results. The results show that the measurement errors, caused by the misalignment of the contact position, should be considered carefully.

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This paper proposes a new biquad structure based on a flipped voltage follower (FVF) for low-power and wide-bandwidth (BW) low pass filter. The proposed biquad structure consists of an FVF and a source follower (SF) for complex pole pair generation and zero cancellation. The presented design provides good linearity at low power consumption, owing to the voltage follower structures. A power/BW ratio (PBWR) is suggested as a performance metric to compare power efficiency to bandwidth, and the proposed biquad structure shows excellent PBWR, especially for low quality factor (Q) design. As a prototype, a fourth order Bessel filter was fabricated in 0.18µm CMOS technology. The measured BW, power consumption, IIP3, and FoM are 120MHz, 180µW, 15dBm, and 0.34fJ, respectively.

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In order to improve the address discharge characteristics, we propose the modified selective reset waveform utilizing the address-bias voltage (V_a-bias) during the ramp-up period. It is revealed that the proper V_a-bias makes the weak discharge between the address and scan electrodes which plays a role in sufficiently removing the wall charge, thereby contributing to minimizing the wall-voltage variation during the address-period. As a result of adopting the V_a-bias in the conventional selective reset driving waveform, it was found that the address discharge delay time can be shortened by approximately 40ns and the address period of each subfield can be significantly reduced by about 43µs.

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A design of dual band amplifier using composite right/left handed (CRLH) transmission line structure is described. First, two single-band matching networks are designed for two frequencies, and they are synthesized into one dual band matching network. It is shown that CRLH transmission lines with arbitrary dual frequencies and dual electrical lengths can be designed. The CRLH transmission line section for the dual band matching network is implemented by lumped inductors and capacitors as the left handed (LH) section, and normal transmission line elements as the right handed (RH) section. As an example, a dual band amplifier for 1800MHz and 2300MHz is designed and measured. The simulated and measured performances well verify the proposed design by showing good matching and gain responses at the desired frequencies.

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A sub-mW current-reuse CMOS VCO is presented for wireless sensor network applications. In order to break the interdependence between the current consumption and the phase noise performance in the conventional current-reuse structure, a tail current source is added to the switching core in such a way that they are simultaneously switched during operation. With this, the current consumption can be maintained at a minimum level while the FET size can be optimally determined for large swing and good phase noise performances. The proposed VCO's advantage of achieving low phase noise at low current consumption is clearly demonstrated by simulations in comparison to the conventional structure. The proposed VCO is implemented in 0.13µm CMOS. It dissipates 0.6mW from 1.2V supply. The measured phase noise at the output frequency of 2.28GHz is -121dBc/Hz at 1MHz offset.

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In this paper, a fifth order curer low-pass filter using as switched-capacitor (SC) architecture is proposed and fabricated with TSMC 0.18µm CMOS process. A fully differential SC is adopted via the bilinear transform of the corresponding analogue RLC passive prototype. To reach the largest possible input dynamic range and save chip area, the method of dynamic range scaling and minimum capacitor scaling is used. Measured results show that the proposed filter achieves a pass-band of 12.1MHz with a sampling rate of 100MHz, a SFDR of 50dB, a stop-band attenuation greater than 50dB and a power consumption of 48.5mW at 1.8V power supply. Including pads, the chip area occupies 1.515 (1.39×1.09)mm². This paper has the feature of low noise, excellent linearity of the filter, and high stability. The experimental results show that it has perfect performance for WiMAX applications and standard is recommended.

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