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An overview and comparison is provided of the different emerging wireless standards and their circuit solutions, which target low data-rate IoT applications, featuring ultra-low-power and/or long-range. Different RF transceiver implementations are presented, including proprietary solutions in license-free spectrum, WLAN-based IEEE802.11ah solutions and mobile operators' alternatives based on emerging long-term evolution (LTEM) standards. The different approaches coming to the market and their circuit design aspects will be discussed.

This work proposes a 12b 60MS/s 0.11μm CMOS Flash-SAR ADC for wireless communication systems. The proposed Flash-SAR ADC is implemented with a 4b flash ADC and a 9b SAR ADC for high speed operation with low power consumption. Furthermore, the shared single sampling-network minimizes a sampling-time mismatch between the flash ADC and the SAR ADC, which is commonly observed in a Flash-SAR ADC without a T/H circuit. The prototype ADC occupies an active die area of 0.31mm2 and consumes 3.2mW at a 1.2V supply voltage.

This paper presents a design, a control scheme, and experiments for a new vibrating magnet robot (ViMbot). Permanent magnets in the new robot vibrate due to an external vibrating magnetic field. The vibration motion of the robot induces the locomotion of the robot. The vibratory dynamic response of the ViMbot is heavily dependent on the frequency of the vibration. This paper shows that the direction of the robot locomotion can be controlled by the vibration frequency of the external magnetic field. To achieve the distinct dynamic responses depending on the vibration frequency, three acrylic plates with different torsional stiffness are attached at three sides of the triangle-shaped ViMbot and then a magnet is attached to each plate. A strategy to find the special frequencies inducing locomotion and associated experiments with the ViMbot are presented. Control experiments for the ViMbot using the special frequencies are also presented. Because the proposed robot is actuated by an external energy source, the robot can move without traditional actuation components such as motors with batteries. This new design concept allows us to miniaturize the proposed robot.

Energy harvesting is one of the key technologies used to realize self-sustaining systems such as wireless sensor networks and health-care devices. Much research on circuit design has been conducted to extract as much energy as possible from transducers, such as the thermoelectric generator (TEG) and the piezoelectric transducer (PZT). Specifically, the energy in a PZT could be extracted more efficiently by utilizing resonance as [1] and [2] demonstrated. However, the maximum output voltage swing in those techniques are limited to twice of the original swing of the PZT, and thus, had a limited energy extraction capability in spite of more energy being available from the PZT. In [3], on the other hand, the large energy is obtained with higher voltage swing, but is limited up to 247% because the load energy is used to increase the output voltage swing of PZT. To obtain far more power from PZT, we propose an alternative resonance technique through which the PZT output swing can be boosted as high as CMOS devices can sustain. This technique is applied to a dual-energy-sourced (PZT and TEG) energy-harvesting interface (EHI) as a battery charger.

Recently, a number of studies are underway about the smart grid for the demand what efficient power management. For these power management in smart grid environments, there are required a system that it can be safely stored and sent various information. In this paper, the user oriented side will be discussed from among the systems that it can be controlled and managed these power. There are devices of various types in the home environments which user live. And it is sent and received all power information as these modules are connected on the smart meters. In this process, it is possible an impersonation attack and a data forgery attack. In this paper, we analyze the security requirements in earlier smart grid environments and then also, propose a certification structure and a secure chip design for efficient message authentication between a smart meter and home appliances.

Auto-stereoscopic multi-view 3D display systems provide 3D perception without the need for special glasses. In Auto-stereoscopic multi-view 3 dimensional system, cross-talk (ratio of being overlapped) and low resolution have been an interrupt-driven that disturb observer to perceive the clear depth perception of images. To solve this problem, it is possible to control the cross-talk of adjoining viewing zone at the observation area, with adjusting interval between each projector lens, in projection-type Auto-stereoscopic multi-view 3 dimensional systems. But, this method not equal to the rate of the crosstalk according to the observing distance. Because this problem, we should know the distance to the minimum crosstalk position. In this paper, we suggest new projection type multi-view 3D display system methods. Suggested method making the ray of light pass through a point located in the front of the image position, the amount of cross-talk can be minimized and the ratio of the amount of overlap along the distance are maintained. By merging adjoining viewing zone the cross-talk can be improved and the luminance of image can be increased. In order to suggested method, we adjust gap between the projector lenses for rate of crosstalk. Through a proposed method, we can know that the ratio of crosstalk is constant according to the varying observing distance.

A 65nm CMOS Low Drop-Out (LDO) Regulator is presented employing Gain Boost-Up and Differential Feed Forward Noise Cancellation (DFFNC) to maximize the Power Supply Rejection. The gain boost-up consists of both negative feedback and positive feedback in the error amplifier. With a 1.2V supply voltage, this LDO regulator has a 200mV drop-out voltage and the ability to handle a maximum 25mA load current. The measurement results show a −47dB PSR ratio up to 10MHz and 0.8% of load regulation for the full load current change.

In this paper, the method of inserting the PEC between conventional EGSs is proposed for a large reflecting structure applications. This method was designed to compensate the unrealizable reflection phase due to limitation of phase range roughly and easily. In the 2 periods EGSs using that method, reflection angle is most similar to intended value of conventional EGS which is designed to have a reflection angle of 30° for a normal incident plane wave. The design is verified in a simulation.

Gamma camera imaging is one of prevalent diagnostic imaging tool for nuclear medicine. Although gamma camera imaging widely used for diagnostic imaging, quantification of gamma camera imaging is difficult due to scattered radiation. Compton scattering is always a problematic phenomenon in gamma camera imaging. In previous study, Siemens symbia scintillation camera was modeled for assessment of septal penetration photons and validation of Monte Carlo simulation code for the Siemens scintillation camera. In this study, optimal energy window for triple energy window (TEW) scatter correction method was assessed in gamma camera for 99mTc, 131I radioisotopes using GATE simulation.

Radioimmunotherapy (RIT) is a promising approach for targeted therapy to treat intractable cancer because radionuclides are delivered more selective to tumor using monoclonal antibody, RIT can be used clinical practice with administration of murine anti-CD20. In this study, the absorbed dose of total body and red marrow of patient enrolled in RIT study was calculated.

We investigated optimized collimator designs for I-131 high energy gamma ray imaging on small animal gamma camera. The simulated structures of the pinhole collimator were evaluated by sensitivity, true, scatter and penetration count rates, and spatial resolution. The parameters, which were pinhole diameter, acceptance angle, and aperture thickness, were determined to improve image resolution with geometric conditions. In this study we showed optimized pinhole design for high energy I-131 imaging to meet the tradeoff between sensitivity and resolution

The total radiated power is one of the most important factor for designing a mobile handset. Thus, in this work, a spatial loss which comes from a human hand was studied to find an effective way to reduce losses and increase the radiated power. A simple lossy object and a half-wavelength dipole antenna were used for the analysis to find a basic principle of the generation of electric fields inside a human hand. From the results, it was verified that there are internal resonance modes in which the electric field and the loss are maximized, and the resonance depends on the shape and size of a lossy object. Therefore, it must be possible to reduce the loss from a human hand by designing the handset antenna to avoid the resonant mode.

By arranging electrical gradient surface of which reflection phase is dependent on surface impedance Z s of EBG, beam steering has been realized. But because this surface impedance (Z s ) strongly depends on the angle of incidence (θ i ) of a plane wave, furthermore, the angular dependence of the surface impedance (Z s ) is different for TE and TM polarized waves, the angle of reflection cannot be calculated acutely in EGS surface when plane wave is excited obliquely. By considering the reflection phase corresponding incident angle & polarization, reflection angle can be controlled by adjusting the gradient of reflection phase across the surfaces. Using theoretical calculations and FEM simulations, it was shown that even though source wave are launched obliquely, the reflected angle was accurately calculated.

20V maximum input voltage and 1A load current hysteretic control based monolithic buck converter with phase locked loop (PLL) is presented. To achieve advantage of hysteretic control and reduce inductor current ripple with ceramic output capacitor, hysteretic based control with PLL is adopted. Furthermore, in order to decrease inductor current ripple due to wide input voltage range, switching frequency is adapted to the input supply voltage. This buck converter is fabricated with 0.35 μm high voltage BiCMOS-DMOS (BCD) process.

A Dual Hybrid Energy transfer media (DHE) Single-Inductor Boost-Inverting Flyback (SIBIF) DC-DC Converter is presented. To increase the converter efficiency, two flying capacitors as well as an inductor are adopted as additional energy transfer media. Furthermore, in order to remove the bifurcation problem occurring in the SIMO type converter, a Bifurcation Free Comparator (BFC) is adopted. The proposed chip is implemented in a 0.5-μm power BCD process and operates at 1.25 MHz with a max efficiency of 89% at an output power of 600 mW.

This paper presents a parking assistance system using visual information. The system input is an image taken by a single camera fixed to the vehicle. In the input image, we detect feature points corresponding to parking slots, among the keypoints detected by SIFT algorithm. The vehicle's location is estimated using detected feature points, and the vehicle's motion is expected using state of vehicle's wheels. Then, the system displays where the vehicle is expected to move in the parking lot based on the current location and the current wheel status. The experimental results show that the presented system can assist a driver in parking the vehicle.

A hybrid-type Single Inductor Boost/Buck Inverting Flyback(SIBBIF) DC-DC Converter is presented. To increase the converter efficiency, a flying capacitor as well as an inductor is adopted as another energy transfer medium together with multi-level gate driver (MLGD). Besides, to enhance load transient response, hybrid fast transient control (HFTC) is adopted. The proposed chip is implemented in a 0.5-µm power BCD process and operates at 1.25 MHz with a max efficiency of 87.1% at an output power of 600 mW.

Polar modulation, where a constant-amplitude phase signal is amplified by an efficient switched-mode power amplifier (PA) and an envelope signal is modulated at the drain of the PA, has been proven to improve efficiency and linearity of the PA system. However, the amplitude modulator (AM) used in such modulation systems must have wide bandwidth, low switching ripple and high efficiency. Although several AM structures have been reported the hybrid switching amplitude modulator (HSAM) shows excellent performance [1–3]. The HSAM consists of a linear amplifier as a voltage source and a switching amplifier as a dependant current source. The linear amplifier using voltage feedback defines output voltage with high frequency information in a bandwidth-expanded envelope signal and the switching amplifier using current feedback drives almost all the current to develop output voltage with the help of a current sensing circuit. If the current sensing circuit does not work well, it makes an offset to the switching amplifier and results in additional power consumption of the linear amplifier [2]. To meet a stringent spectral mask, low output impedance of the linear amplifier is needed [1]. In conclusion, wide bandwidth and low output impedance of the linear amplifier, and accurate current sensing are critical points in the design of the HSAM.

In this paper, we propose an estimation method of golf club's loci and attitudes using a 3-axis acceleration sensor1. Extraction of golf club's loci and attitudes from the 3-axis acceleration sensor is difficult. Because an output values of a 3-axis acceleration sensor are affected by gravity acceleration. For this reason, we use an appropriate golf swing model that describes relationships of golf swing properties. Based on the swing model, we estimate golf club's loci and attitudes that appropriative to the output of sensor. By applying the estimated golf club's loci and attitudes, we made a golf game. Using our estimation, we get advantages of lower cost and little constraints of location compared to other researches.

In this paper, we present a method to optimally manage the access slots for the initial ranging contention process in IEEE802.16e air interface. In conventional method, the number of the initial access slot is fixed to a large number in common circumstance. The reason using the static large slot is to reduce the initial access collisions by slot contentions of the mobile terminals. Therefore the usage rate of the initial ranging slot may be lower in the normal mobile access demands. Furthermore future mobile access demands can be changed to more or to less. Therefore the maintenance cost will be increased to rearrange the initial ranging slots. In these regards, we develop an automatic and adaptive slot allocation method for the initial ranging contention process. The method uses simply measureable two system parameters, and we develop a simple algorithm that can automatically track the current optimal slot numbers. In simulation results, we show that the method finds the optimal slot numbers in terms of optimal mobile access delay and slot usage rate. From the results, it is also considered that this method can provide an automatic process for the initial mobile access process of any cellular networks.

A hybrid switching amplifier for dynamic power supply applications is presented. To achieve both high speed and high efficiency, a wideband buffered linear amplifier is combined with a hysteretic controlled switching amplifier. To obtain high linearity and reduce switching loss at low power levels where the switching amplifier is not needed, the linear amplifier supplies all load current with the switching one disabled. The novel two-quadrant linear amplifier as a voltage source for regulating the output voltage has very low output impedance of about 200 m Omega around the switching frequency, a high current-driving capability of maximum 220 mA and a bandwidth wider than 7 MHz. The hybrid amplifier can drive a circuit with an equivalent impedance of 7 Omega and supply a maximum output power of 1.1 W with a maximum efficiency of about 91%. Its output voltage ranges from 0.3 V to 2.9 V for a 3.3V supply. The chip is fabricated using only thick-oxide devices in a 0.13 um CMOS process and occupies an area of 3.9 mm2.

We have successfully developed integration friendly dual metal gate process utilizing a dual thickness metal inserted poly-Si stacks (DT-MIPS) structure; poly-Si/TaN/HfON stacks for nMOS and poly-Si/capping metal layer(c-ML)/AlOx/TaN/HfON stacks for pMOS. First, in spite of different metal thickness on n/pMOS, a high-selectivity gate etch process can completely remove metal and HfON layers from the S/D active regions with negligible Si recess in both n/pMOS. Consequently, in both short and long channel devices, n/pMOS Vth values of ~plusmn0.35 V are obtained without counter channel doping. Moreover, excellent drive currents (620/250 muA/um for n/pMOS at Ioff=20 pA/um and Vdd=1.2 V) are obtained without using any mobility enhancement technique. Finally, we confirm that the estimated operation voltages for 10 years lifetime for both nMOS PBTI and pMOS NBTI are well beyond the 1.2 V.

The authors have successfully developed a mass production friendly single metal gate process utilizing an ultra-thin metal inserted poly-Si stack (UT-MIPS) structure. First, the inserted metal gate thickness effects on device performances are carefully examined, and then the other parameters are optimized to give the best performance. As a results, low and symmetrical short channel Vth (0.44/-0.48 V for n/pMOS) and excellent drive currents (620/230 muA/mum for n/pMOS at Ioff =20pA/mum and Vdd=1.2 V) are obtained without using any mobility enhancement strain technology. The estimated operation voltage for 10 years lifetime of optimized UT-MIPS devices (1.25 V for nMOS PBTI and 1.5 V pMOS NBTI) are well beyond the 1.2 V, showing the good reliability characteristics of UT-MIPS devices as well

We propose a novel Vth, control method for HfSiON (or HfO2) with poly-Si and metal inserted poly-Si stacks (MIPS) gates. By using a selective AlOx etch (SAE) process, we successfully integrate dual high-k gate oxide scheme; HfSiO/poly-Si stack for nMOS and HfSiO/AlOx/poly-Si stack for pMOS. Therefore, symmetrical Vth values of 0.43V(nMOS)/-0.44V (pMOS) have been obtained in poly-Si gate. For MIPS gate, we perform the SAE process with impurity incorporation at the channel region, such as N 2 for nMOS and F for pMOS. Consequently, nMOS Vth of 0.35V and pMOS Vth of -0.45V are obtained without counter channel doping. Moreover, we find out that impurity incorporation at the channel also improves mobility and reliability characteristics. Finally, by using the SAE process with impurity incorporation, maximum operating voltages above 1.0V are obtained by an extrapolated 10 years lifetime