Inter-vehicle distance measuring technique is widely used for Driving Assistance System (DAS) such as Adaptive Cruise Control (ACC) and Forward Collision Warning (FCW) which are useful for safety enhancement as well as driving convenience. In this paper, we propose a new method for providing accurate longitudinal inter-vehicle distance measurement by using a monocular camera and a line laser. Experimental results show that the proposed method outperforms the disparity-based method and the error in distance measurement is low enough even in nighttime as much as daytime.

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Capnometers monitor the concentration of CO₂ in exhaled breath, which can be a life saving modality. High cost, big size and high power consumption of the conventional capnometers limit their scope and adaption. To overcome these issues, a CMOS MEMS microcantilever based CO₂ sensor is proposed for capnometric applications. The microcantilever is manufactured using CMOS MEMS technology and its critical parameters are analytically investigated. The optimized microcantilever has a quality factor, sensitivity and resolution of 3116, 16 mHz/ppm and 0.31 ppb, respectively.

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This article presents a method to enhance tolerance to voltage and temperature variations in an injection-locked PLL. The proposed method can enhance the tolerance to voltage and temperature variations by turning on or off a supplementary current source of the oscillator in the injection-locked PLL through the RC switch with a large time constant. This configuration increases the tolerance range to the supply voltage variation by 33.8%, compared to the conventional injection-locked PLL in [5]. The proposed method is verified by the calculation and simulations. They show that the PLL can maintain the stable lock state during the switching of the supplementary current source.

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This paper presents versatile formulas that characterize wireless power transfer schemes in arbitrary coupling topologies. Maximum available coupling efficiency is formulated in two-port immittance matrix domain invariant to source and load conditions. Key performance index k-Q product is extended to general cases even where resonance or filtering model is inapplicable. Typical capacitive- and inductive-coupling schemes are shown with their k-Q product instances.

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IEC 61508-2010 puts special limits on the on-chip redundancy of one single chip, for example the safety integrity level (SIL) is limited up to SIL 3. About this, however, there are no specific explanations. Based on the safety-critical system of on-chip redundancy for a typical programmable logic device (FPGA), this paper proves that the highest SIL is 3; analyses the factors that may impact the safety integrity of redundancy system, and furthermore, provides reasonable solutions. The results show that the use of 1oo2 channel redundancy scheme can effectively improve the safety integrity level of the on-chip redundancy.

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Battery energy nonlinear consumption is a key issue for wireless sensor networks (WSNs) nodes which operate on nonrenewable batteries. The topic has been widely studied by researchers in current years. However, to the best of our knowledge, there is no literature that provides the exact reason for the energy consumption nonlinear character of a battery, and calculates the exact nth value of a battery energy under nonlinear consumption condition. In this paper, we develop a realistic battery energy consumption model, combining with transmitting signal energy and circuit power consumption in WSNs. Based on the developed model, we study the battery energy consumption based on packets instead of the pulses under two packet assembly approaches that are length-based and time-based assembly approaches. An extensive simulation is given to validate the proposed model and evaluate the performance of the nonlinear battery energy consumption.

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A reliable and low error dual modular redundancy FIR filter with wide protection window has been proposed in this paper. We improved the feedback mechanism by using a multiplexer to recover the soft error struck module from error immediately. The recovering time of soft error struck module can be shortened 87.18%, and the output error rate can be lowered by 4.5 times.

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In this study, we investigate the performance of the variants of the induced dimension reduction (IDR) in large-scale electromagnetic scattering problems. We also focus on the tolerance to the so-call spurious convergence and convergence property of the IDR variant methods. Comparative numerical experiments, using IDR(s), Bi-IDR(s), and GIDR(s, L), reveal that GIDR(s, L) with L = 2 or 4 and an s value of around 15 shows the best performance with respect to the balance between the convergence property and the tolerance to the spurious convergence for problems with several levels of geometry complexity.

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A broadband 5-bit CMOS step attenuator in small area with low insertion loss is presented in this paper, which is implemented with three independent attenuation modules and two compact T-type attenuation networks. Two of the independent modules are switched π-type, and the other is bridged-T type. The compact T-type attenuation networks share the series branches with the adjacent modules to decrease the chip area and insertion loss. The proposed attenuator has a maximum attenuation range of 0–31 dB with 1 dB-increase at the operational frequency range of 5–20 GHz and consumes a layout area cost of 0.44 mm². The insertion loss is less than 8.7 dB. The RMS insertion amplitude and phase error are less than 0.45 dB and 5.7°, respectively.

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One of the audio watermarking schemes with highest payload published to date is Fallahpour scheme, achieving about 3 kbps [1]. A keybased security improvement to this algorithm is proposed in [2] while significatively maintaining the payload. In this letter, a high throughput and compact hardware architecture for the Security Improved Fallahpour Audio Watermarking Scheme is proposed, demonstrating the suitability of this algorithm for real-time applications.

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A novel voltage-mode multifunction biquadratic filter with one input and six outputs is presented. The proposed circuit uses two inverting second-generation current conveyors (ICCIIs), two grounded capacitors, and four resistors. The circuit offers realizing inverting and non-inverting lowpass, bandpass, and highpass filters, simultaneously, without component matching conditions, using grounded capacitors and low active and passive sensitivities. Experimental results are provided to demonstrate the theoretical analysis.

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This paper presents a new high input impedance voltage-mode universal biquadratic filter constructing with two differential difference current conveyor transconductance amplifiers (DDCCTAs), two grounded capacitors and two resistors. The presented filter can realize all the five standard biquadratic functions simultaneously without requiring any component matching conditions. Moreover, the circuit enjoys (i) the employment of two grounded capacitors, (ii) high input impedance and (iii) orthogonal tunability of the parameters resonance angular frequency (ω_o) and quality factor (Q). HSPICE simulation results confirm the theoretical analysis.

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The ionospheric sounding system is a type of high-frequency over-the-horizon skywave radar developed for ionospheric research and HF channel management. The hardware system of a portable low-power multifunctional ionospheric sounding system is presented in this paper. The device can be used for typical ionospheric sounding and spectrum monitoring at monostatic and bistatic station. The system structure and the primary module are depicted in detail. Typical experimental results demonstrate that the design of this device is successful for ionospheric researching.

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