We consider the use of the additive white Gaussian noise channel to achieve information theoretically secure oblivious transfer. A protocol for this primitive that ensures the correctness and privacy for players is presented together with the signal design. We also study the information theoretic efficiency of the protocol, and some more practical issues where the parameter of the channel is unknown to the players.

We propose a surface profiling algorithm by white-light interferometry that extends sampling interval to twice of the widest interval among those used in conventional algorithms. The proposed algorithm uses a novel function called an in-phase component of an interferogram to detect the peak of the interferogram, while conventional algorithms used the squared-envelope function or the envelope function. We show that the in-phase component has the same peak as the corresponding interferogram when an optical filter has a symmetric spectral distribution. We further show that the in-phase component can be reconstructed from sampled values of the interferogram using the so-called quadrature sampling technique. Since reconstruction formulas used in the algorithm are very simple, the proposed algorithm requires low computational costs. Simulation results show the effectiveness of the proposed algorithm.

This paper presents a measurement method for determining effective conductivity of copper-clad dielectric laminate substrates in the millimeter-wave region. The conductivity is indirectly evaluated from measured resonant frequencies and unloaded Q values of a number of Whispering Gallery modes excited in a circular disk sample, which consists of a copper-clad dielectric substrate with a large diameter of 20-30 wavelengths. We can, therefore, obtain easily the frequency dependence of the effective conductivity of the sample under test in a wide range of frequency at once. Almost identical conductivity is predicted for two kinds of WG resonators (the copper-clad type and the sandwich type) with different field distribution; it is self-consistent and provides the important foundation for the method if not for the alternative method at this moment. We measure three kinds of copper foils in 55-65 GHz band, where the conductivity of electrodeposited copper foil is smaller than that of rolled copper foil and shiny-both-sides copper foil. The measured conductivity for the electrodeposited copper foil decreases with an increase in the frequency. The transmission losses measured for microstrip lines which are fabricated from these substrates are accurately predicted with the conductivity evaluated by this method.

Low Power Design has become a significant requirement when the CMOS technology entered the nanometer era. Multiple-Supply Voltage (MSV) is a popular and effective method for both dynamic and static power reduction while maintaining performance. Level shifters may cause area and Interconnect Length Overhead (ILO), and should be considered at both floorplanning and post-floorplanning stages. In this paper, we propose a two phases algorithm framework, called VLSAF, to solve voltage and level shifter assignment problem. At floorplanning phase, we use a convex cost network flow algorithm to assign voltage and a minimum cost flow algorithm to handle level-shifter assignment. At post-floorplanning phase, a heuristic method is adopted to redistribute white spaces and calculate the positions and shapes of level shifters. The experimental results show VLSAF is effective.

We describe a co-channel interference rejection scheme that is suitable for QR-decomposition maximum likelihood detection (MLD) in multiple-input and multiple output (MIMO) systems. A pre-whitening matrix for interference rejection is decomposed into a triangular matrix and its Hermitian matrix by using a complex Gaxpy version of the Cholesky algorithm. The decomposed triangular matrix is used as a spatial pre-filter to whiten co-channel interference. Simulation results demonstrate that the proposed scheme can suppress co-channel interference streams at the cost of receive diversity order and achieves better transmission performance than QR-decomposition MLD itself in MIMO channels with co-channel interference.

An antenna-permutation (AP) scheme is described for channel-vector quantization (CVQ) in zero-forcing beamforming (ZFBF) multiuser multiple-input and multiple-output orthogonal frequency-division multiplexing systems with multiple receive antennas. Different sets of multiple channel sub-matrices are selected for different subcarriers and then quantized to multiple quantization vectors for finite rate feedback. Based on the quantization vectors, ZFBF provides a single stream or multiple streams to users while increasing frequency selectivity. Simulation results demonstrate that AP-CVQ with four-bit quantization that incorporates with pre-whitening maximum likelihood detection for two stream reception achieved better average packet error rates than minimum mean square error receive beamforming for single stream reception when the frequency selectivity was not severe.

In this paper, a novel model of Gaussian pulse propagation in optical fiber is proposed to comprehensively analyze the impact of Group Velocity Dispersion (GVD) on the performance of two-dimensional wavelength hopping/time spreading optical code division multiple access (2-D WH/TS OCDMA) systems. In addition, many noise and interferences, including multiple access interference (MAI), optical beating interference (OBI), and receiver's noise are included in the analysis. Besides, we propose to use the heterodyne detection receiver so that the receiver's sensitivity can be improved. Analytical results show that, under the impact of GVD, the number of supportable users is extremely decreased and the maximum transmission length (i.e. the length at which BER 10-9 can be maintained) is remarkably shortened in the case of normal single mode fiber (ITU-T G.652) is used. The main factor that limits the system performance is time skewing. In addition, we show how the impact of GVD is relieved by dispersion-shifted fiber (ITU-T G.653). For example, a system with 321 Gbit/s users can achieve a maximum transmission length of 111 km when transmitted optical power per bit is -5 dBm.

Two discrete-time Wirtinger-type inequalities relating the power of a finite-length signal to that of its circularly-convolved version are developed. The usual boundary conditions that accompany the existing Wirtinger-type inequalities are relaxed in the proposed inequalities and the equalizing sinusoidal signal is free to have an arbitrary phase angle. A measure of this sinusoidal signal's power, when corrupted with additive noise, is proposed. The application of the proposed measure, calculated as a ratio, in the evaluation of the power of a sinusoid of arbitrary phase with the angular frequency π/N, where N is the signal length, is thoroughly studied and analyzed under additive noise of arbitrary statistical characteristic. The ratio can be used to gauge the power of sinusoids of frequency π/N with a small amount of computation by referring to a ratio-versus-SNR curve and using it to make an estimation of the noise-corrupted sinusoid's SNR. The case of additive white noise is also analyzed. A sample permutation scheme followed by sign modulation is proposed for enlarging the class of target sinusoids to those with frequencies M π/N, where M and N are mutually prime positive integers. Tandem application of the proposed scheme and ratio offers a simple method to gauge the power of sinusoids buried in noise. The generalization of the inequalities to convolution kernels of higher orders as well as the simplification of the proposed inequalities have also been studied.

When we watch television or computer monitor under a certain viewing condition, we partially adapt to the display and partially to the ambient light. As an illumination level and chromaticity change, the eye's subjective white point changes between the display's white point and the ambient light's white point. In this paper, we propose a model that could predict the white point under a mixed adaptation condition including display and illuminant. Finally we verify this model by experimental results.

High-efficiency pure-white organic light-emitting diodes (OLEDs) were fabricated using small polysilicic acid nanodot embedded polymeric hole-transporting layer. By incorporating the nanodot, the efficiency of a solution-processed phosphorescent white OLED was increased from 6.8 to 23.7 lm/W, an improvement of 250%. 17.1 lm/W was obtained while the same concept was applied on a mixed-host composed fluorescent white OLED.

Augmented reality tasks require a high-reliability tracking method. Large tracking error causes many problems during AR applications. Tracking error estimation should be integrated with them to improve the reliability of tracking methods. Although some tracking error estimation methods have been developed, they are not feasible to be integrated because of computational speed and accuracy. For this study, a tracking error estimation algorithm with screen error estimation based on the characteristic of linecode marker was applied. It can rapidly estimate tracking error. An evaluation experiment was conducted to compare the estimated tracking error and the actual measured tracking error. Results show that the algorithm is reliable and sufficiently fast to be used for real-time tracking error warning or tracking accuracy improvement methods.

We propose a noise suppression algorithm with the Kalman filter theory. The algorithm aims to achieve robust noise suppression for the additive white and colored disturbance from the canonical state space models with (i) a state equation composed of the speech signal and (ii) an observation equation composed of the speech signal and additive noise. The remarkable features of the proposed algorithm are (1) applied to adaptive white and colored noises where the additive colored noise uses babble noise, (2) realization of high performance noise suppression without sacrificing high quality of the speech signal despite simple noise suppression using only the Kalman filter algorithm, while many conventional methods based on the Kalman filter theory usually perform the noise suppression using the parameter estimation algorithm of AR (auto-regressive) system and the Kalman filter algorithm. We show the effectiveness of the proposed method, which utilizes the Kalman filter theory for the proposed canonical state space model with the colored driving source, using numerical results and subjective evaluation results.

We have derived the novel extended UTD (Uniform Geometrical Theory of Diffraction) solution and the novel modified UTD solution for the back scattering of an incident whispering gallery (WG) mode on the edge of a cylindrically curved conducting sheet. By comparing with the reference solution obtained from the integral representation of the scattered field by integrating numerically along the integration path, we have confirmed the validity and the utility of the novel asymptotic solutions proposed in the present study. It is shown that the extended UTD solution can be connected smoothly to the modified UTD solution on the geometrical boundary separating the edge-diffracted ray and the surface-diffracted ray.

An explicit expression for the impulse response coefficients of the predictive FIR digital filters is derived. The formula specifies a four-parameter family of smoothing FIR digital filters containing the Savitsky-Goaly filters, the Heinonen-Neuvo polynomial predictors, and the smoothing differentiators of arbitrary integer orders. The Hahn polynomials, which are orthogonal with respect to a discrete variable, are the main tool employed in the derivation of the formula. A recursive formula for the computation of the transfer function of the filters, which is the z-transform of a terminated sequence of polynomial ordinates, is also introduced. The formula can be used to design structures with low computational complexity for filters of any order.

We measured the complex permittivities of whole blood and blood plasma in quasi millimeter and millimeter wave bands using a coaxial probe method. The validity of these measurements was confirmed by comparing with those of a different measurement method, i.e., a dielectric tube method. It is shown that the complex permittivities of the blood samples are similar to those of water in quasi millimeter and millimeter wave bands. Furthermore, the temperature dependences of the complex permittivities of the samples were measured.

When a cylindrically curved concave conducting surface is terminated abruptly at the edge, the whispering gallery (WG) mode propagating toward the edge direction is radiated into the free space from the aperture plane at the edge. In this paper, by applying the new analysis method, we shall derive a uniform geometrical theory of diffraction solution (UTD) for the electric-type WG mode radiation field applicable in the transition region near the geometrical boundaries produced by the incident modal ray on the edge of the curved surface. The UTD is represented by the summation of the solution for the geometrical ray converted from the modal ray of the WG mode and the solution for the uniform edge diffracted ray scattered at the cylindrically curved edge. By comparing with the reference solution obtained numerically from the integral representation of the radiation field, we will confirm the validity and the utility of the UTD proposed in this paper.

We focus on the development of new silicate phosphors for a white LED. In the europium doped silicate system, four LED phosphor candidates-- Li2SrSiO4:Eu2+, Ba9Sc2Si6O24:Eu2+ , Ca3Si2O7:Eu2+ and Ba2MgSi2O7:Eu2+ were found. Luminescent properties under near UV and visible excitation were investigated for the new Eu2+ doped LED silicate phosphors. These new phosphors have a relatively strong absorption band in a long wavelength region.

The number of bipolar orthogonal codes such as Walsh-Hadamard (WH) is limited due to implementation complexity which is proportional to the number of generated codes. Therefore, the data rate of multi-code systems [1] is restricted too. This paper presents a design of novel multi-level quasi-orthogonal codes (MLQOCs) using advanced orthogonal code group (AOCG) [2] derived from WH matrix to provide more spreading codes while retaining the chip-rate and length of the original WH codes. Moreover, we propose a multi-code multi-carrier CDMA (Mc-MC CDMA) system using MLQOCs to obtain high and variable transmission speed.

In this study, we achieved predictable control of a wheelchair by changing the existing mapping method of the joystick, which considers the consecutive operations of a motor of a wheelchair, to a new mapping method that corresponds to the internal model of a human being. Since the existing method uses the polar coordinate system, it is not easy at all to use this method to predict either the direction of motion or the operating order for changing the position of the wheelchair according to the requirements of an operator. In order to improve the embodiment, we divided the existing joystick mapping method into two degrees of freedom-one in the vertical axis that can control the velocity and the other, in the horizontal axis for direction control. Based on this division, we implemented a wheelchair model that can be controlled by the electromyography (EMG) signal from the neck and the arm muscles of an operator. This was achieved by mapping the divided degrees of freedom onto the degrees of freedom of the neck and arm of the operator. In this case, since the operator controls the direction of motion by the joint of his/her neck, he/she can move the wheelchair in the desired direction; thus, a more intuitive human interface is implemented.

This paper presents a new generative approach for generating two-dimensional signals having both a low peak factor (crest factor) and a flat power spectrum. The flat power spectrum provides zero auto-correlation, except at the zero shift. The proposed method is a generative scheme, not a search method, and produces a two-dimensional signal of size 2(2n1+1)2(2n2+1)2 for an arbitrary pair of positive integers n1 and n2 without any computer search. The peak factor of the proposed signal is equal to the peak factor of a single trigonometric function.