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A trapezoid ultra-wideband antenna using Sierpinski sieve fractal was proposed to reduce the size and expand the bandwidth of the antenna. The effect of the fractal iteration factor (Kn) on the return loss of the antenna was simulated. The return loss, group delay, and path loss (|S 21|) of the antenna were simulated and measured to show that the proposed antenna may be used well for UWB applications with the wide operating bandwidth and good impedance matching. The radiation characteristics of dipole-like pattern and gain variation (2–4 dBi) were obtained over the frequency band.

In this study, two red wines were developed, with and without sugar addition, from a mixture of two different grape varieties, Gerbong (Vitis labrusca L.) 60% and Campbell Early (V. labrusca B.) 40%. Their chemical and sensory profiles were determined and compared with a French Beaujolais Nouveau wine of Chateau Talance using descriptive, physicochemical and volatile analyses. Colour, six aroma, and five taste attributes were evaluated by an expert panel of nine judges. Sample wines were analyzed for titratable acidity, ethanol, pH, Hunter colorimeter value, phenolic compounds, and organic acids. From the volatile analysis of sample wines, 10 acids, 12 alcohols, 10 esters, 7 volatile phenols, 5 furans, and 3 miscellaneous compounds were identified. From the principal component analysis of the descriptive data, wines were primarily separated along the first PC, which explained 93% of the total variance between the Korean wines with high intensities of “ripe-fruit aroma”, “caramel aroma”, and “sour” attributes and the French wine that was high in “woody aroma”, “astringent”, “mineral aroma”, and “colour” attributes.

By using a non-isolated power combiner, the overall power efficiency can be improved by reducing the wasted power at the combined out-phased signal. To further improve the efficiency of the low-power mode, a multi-power mode out-phasing power amplifier (PA) is proposed with load modulation by switches. Compared with the conventional linear amplification using nonlinear component (LINC) transmitter, the proposed multi-level LINC improves the power-added-efficiency more than 40% for a 7 dB peak-to-average power ratio orthogonal frequency division multiplexing signal. To the authors' knowledge, the proposed LINC PA is the first multi-level LINC PA without multiple power supplies.

Recently, cognitive radio (CR) technology has been proposed as a way of increasing spectrum utilization efficiency. A CR system seeks to use the unoccupied spectrum segments by sensing the spectrum before transmitting to preserve the rights of privileged primary users (Haykin, 2006). IEEE 802.22 is the working group on wireless regional area network (WRAN) for the license-exempt use of the U.S. TV broadcasting band. Such use requires that new transceivers possess CR functionality. A fully-integrated CMOS receiver is presented with a CR spectrum-sensing functionality of arbitrary detection bandwidth over the UHF band. This capability is called multi-resolution spectrum sensing (MRSS).

Spectrum sensing technology is most vital to the implementation of a CR system using dynamic spectrum resource management. This paper suggested a CR system architecture with a wideband dual-stage spectrum sensing technique - a coarse and a fine spectrum sensing. Specifically, a coarse spectrum sensing technique adopted wavelet transforms in this architecture to provide a multi-resolution spectrum sensing (MRSS) feature. Analog implementation of the MRSS block offers wideband, low-power, and real-time operation. A fine spectrum sensing technique used the beneficial properties of auto-correlation in time domain - temporal signature detection (TSD). This TSD technique enables identifying the unique signature feature of each specific signal type. Moreover, this feature detection technique in time domain realizes simple and fast spectrum-detection compared to spectral feature detection methods.