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Finite control-set model predictive control (FCS-MPC) shows superior dynamic performance with simple structure for motor drives. However, conventional FCS-MPC method presents unfixed switching frequency, making it intractable for the design of heat sinks and output filters. To address this issue, this study is devoted to developing a new FCS-MPC strategy with constant switching frequency for permanent magnet synchronous motor (PMSM) drives fed by three-level T-type inverter. The switching frequency regulation is realized by extending the period control technique, where the periods are measured between each rising edge and falling edge of the gate signals. The proposed algorithm can be embedded in the iterative process of the FCS-MPC, which can easily achieve the fixed switching frequency with balanced neutral point potential. The performance of this control strategy is numerically evaluated and experimentally verified by an 11-kW PMSM drive platform.

When the input signal has been interfered and glitches occur, the power consumption of Double-Edge Triggered Flip-Flops (DETFFs) will significantly increase. To effectively reduce the power consumption, this paper presents an anti-interference low-power DETFF based on C-elements. The improved C-element is used in this DETFF, which effectively blocks the glitches in the input signal, prevents redundant transitions inside the DETFF, and reduces the charge and discharge frequencies of the transistor. The C-element has also added pull-up and pull-down paths, reducing its latency. Compared with other existing DETFFs, the DETFF proposed in this paper only flips once on the clock edge, which greatly reduces the redundant transitions caused by glitches and effectively reduces power consumption. This paper uses HSPICE to simulate the proposed DETFF and other 10 DETFFs. The findings show that compared with the other 10 types of DETFFs, the proposed DETFF has achieved large performance indexes in the total power consumption, total power consumption with glitches, delays, and power delay product. A detailed analysis of variance indicates that the proposed DETFF features less sensitivity to process, voltage, temperature, and Negative Bias Temperature Instability (NBTI)-induced aging variations.

A sub-sampling phase-locked loop (SSPLL) with a subsampling delay-locked loop is presented to extend the loop bandwidth and achieve the low jitter. A falling-edge tuning loop is added to align the falling edge of the reference clock with the rising one of the output clock. The proposed SSPLL is realized in a 0.18μm CMOS process and its active area is 0.185mm2. At the output frequency of 2.2GHz, the proposed SSPLL achieves an inband phase noise of -111.83dBc/Hz and -116.41dBc/Hz at 100kHz and 4MHz offset frequency respectively with a division ratio of 44. Its root-mean-square jitter integrated from 10kHz to 100MHz is 655fs. The measured reference spur is -50.3dBc.

Although the individual channel readout method can improve the performance of PET detectors with pixelated photo-sensors, such as silicon photomultiplier (SiPM), this method leads to a significant increase in the number of readout channels. In this study, we proposed a novel multiplexing method that could effectively reduce the number of readout channels to reduce system complexity and development cost. The proposed multiplexing circuit was designed to generate bipolar pulses with different zero-crossing points by adjusting the time constant of the high-pass filter connected to each channel of a pixelated photo-sensor. The channel position of the detected gamma-ray was identified by estimating the width between the rising edge and the zero-crossing point of the bipolar pulse. In order to evaluate the performance of the proposed multiplexing circuit, four detector blocks, each consisting of a 4 × 4 array of 3 mm × 3 mm × 20 mm LYSO and a 4 × 4 SiPM array, were constructed. The average energy resolution was 13.2 ± 1.1% for all 64 crystal pixels and each pixel position was accurately identified. A coincidence timing resolution was 580 ± 12 ps. The experimental results indicated that the novel multiplexing method proposed in this study is able to effectively reduce the number of readout channels while maintaining accurate position identification with good energy and timing performance. In addition, it could be useful for the development of PET systems consisting of a large number of pixelated detectors.

Dynamic degradation becomes a critical issue for thin-film transistors (TFTs) used in emerging new displays driven by high frequency gate voltage ${V}_{\text {G}}$ pulses. In this study, ${V}_{\text {G}}$ pulse rising edge dependent dynamic hot carrier degradation of poly-Si TFTs is investigated. It is demonstrated that rising edge of ${V}_{\text {G}}$ pulses which swing within the OFF-state of TFTs causes the degradation, while that of normal ${V}_{\text {G}}$ pulses which switch between the ON and OFF states across the flat band voltage ${V}_{\text {FB}}$ of TFTs does not. Based on transient TCAD simulation, the underlying mechanism of rising edge dependent degradation is proposed, which is based on the non-equilibrium PN junction degradation model previously proposed to explain ${V}_{\text {G}}$ pulse falling edge dependent degradation of poly-Si TFTs. Hence, the dynamic degradation model of poly-Si TFTs related to both rising and falling edge of the ${V}_{\text {G}}$ pulses can be unified now, which is applicable to fast gate pulses with steep rising and/or falling edges in sub- $\mu \text{s}$ level.

B-dot sensor, as an important device, is extensively employed to measure the current flowing in the magnetically insulated transmission line (MITL). To shield the output signal of the B-dot sensor from electron flow and high electrical field in the MITL anode-cathode (A-K) gap and also avoid the electrical breakdown in the A-K gap, the sensor is often covered with the metallic film and located in a conductor cavity penetrating the MITL electrode hole simultaneously. The frequency response properties of such kind of sensor are investigated. The experiment results indicate that the upper limited response frequencies of the sensors with and without the attached $5-\mu $ m-thick Ni-Chrome foil are 50 MHz and 148 MHz, respectively. Moreover, as a result of penetration of magnetic flux into the cavity’s wall and the wire loops wound to form the sensor, the low-frequency components of the B-dot sensor output signal are amplified, consequently the falling edge of the waveform given by the B-dot probe will be distorted. We have proposed a method to make a first-order correction for such effect by using a passive resistor-capacitor integrator instead of the numerical process suggested previously. The integrator combines the behaviors of integration and compensation of the B-dot sensor output. The actual measured current waveform can be directly obtained by multiplying the output signal of the integrator by the sensitivity of the B-dot monitor. The B-dot sensors and this post-processing method have been successfully used on a pulsed power accelerator.

Screening out the defects in the TSV manufacturing process and eliminating the resistive open fault and leakage fault as early as possible are beneficial to improve the yield and reliability of 3D ICs. The existing prebond test methods are confined to the test accuracy and de- tection range, especially the test confusion prob- lem and the lack of diagnosable ability under the coexistence of multiple faults. Based on the uc- tuation of delay feature caused by faults, a kind of fault coexistence and grading aware TSV test method is proposed to enhance the yield and reli- ability of TSVs in this paper. The reference TSV and the TSV under test are input with test stim- uli simultaneously. Furthermore, the designed delay extraction circuit is utilized to generate the rising edge and the falling edge separately and additional fault grading circuit can be enriched according to the test requirements. Finally, a one bit comparator at the capture end is used to detect whether two pulse signals arrive simul- taneously, so as to determine whether there is a fault and the type of fault. The simulation results indicate that the detection range of resistive open fault is more than 281 , and the detection range of leakage fault is less than 223 M , which is bet- ter than most existing methods. While effective- ly solving resistive open fault and leakage fault, it can also successfully deal with the coexistence of two kinds of faults and achieve a 5-level fault grading ability with relatively low area overhead.

A new method is proposed for the measurement of the junction temperature of insulated gate bipolar transistors (IGBTs) during operation. The application of this method overcomes the problems arising from the complexity of measurement circuits or the difficulty of tests. The proposed measurement method uses the turn-on Miller plateau duration (tmon), i.e., the duration from the first rising edge to the second rising edge of the gate–emitter voltage, of an IGBT. The obtained results show that tmon is strongly linear with respect to temperature. For comparison, the temperature-sensitive electrical parameters (TSEPs) turn-off Miller plateau duration (i.e., the duration between the two falling edges of the Vge-off curve) were also measured. The obtained results show that tmon exhibits a high sensitivity that permits accurate determination of the junction temperatures of IGBTs.

The destruction of a superinsulating state by pulsed voltage in thin NbTiN films is studied. A delay of the destruction of the superinsulating state after the rising edge of the pulse is discovered. The time of recovery and the time of destruction of the superinsulating state are determined.

We propose and demonstrate on-chip all-optical control of a single resonance in a graphene-on-silicon nanobeam cavity using thermo-optic (TO) effect. In the design, the graphene sheet covered on the nanobeam cavity is patterned in a “U” shape, which enables the device to maintain a constant quality factor and a high extinction ratio (ER) after graphene transfer. Benefiting from the ultra-small optical mode volume of the nanobeam cavity and the high thermal conductivity of graphene, efficient all-optical control of a single resonance is implemented with a tuning efficiency of 0.0346 nm/mW. All-optical switching is also demonstrated with a switching power of 47 mW at a high ER of ∼16 dB. Moreover, the 10%–90% switching times are 3.24 μs and 5.52 μs for the rising edge and the falling edge, respectively. Such graphene-assisted device potentially could be a good candidate to realize efficient on-chip all-optical control of an individual resonance with a high ER.

This article presents a technique titled metastability condition detection and correction (MEDAC) that is featured in a near-threshold voltage (NTV) network-on-chip (NoC) hardware. The proposed technique introduces a double-sampling-based circuitry to detect whether the input data arrives too close to the receiver’s clock edge, which is defined as a metastability condition. The MEDAC also contains a metastability condition mitigation scheme to monitor if the occurrence of such metastability conditions is frequent, and adaptively tune the receiver’s clock phase to increase the mean time between metastability conditions. We prototype a test chip of the NoC in a 65-nm low-power process, which supports four independent voltage/frequency (V/F) domains in globally asynchronous locally synchronous (GALS) systems. Measurements across 0.4–1-V supply voltages with 13 different frequency ratios from 0.25 to 4 show that the MEDAC can well detect the metastability conditions and reduce the probability of entering such conditions by one to three orders of magnitude. This reduction, in turn, reduces the potential incorrect packets, thereby improving the data rate and energy efficiency by up to 21.1% and 27.2%, respectively.

The rising edge of the output pulses affects the discharged mechanism and efficiency of the nonthermal plasma generation. In the traditional Marx-type pulse generators, the magnetic isolation driving circuit could not adjust the rising edge of the output pulses and limits the application on a capacitive load. In this article, the factors affecting the rising edge of output pulses are analyzed. And a driving circuit based on magnetic isolation is proposed, which can control the rising edge of the output pulses. A synchronous driving signal is used to control multiple groups of switches using different sequences, and the magnetic core does not limit the driving signals. The experiments were carried out using a seven-stage solid-state Marx modulator. From the results, the rectangular pulses and stepped pulses are obtained at a capacitive load, and the 0.1– $2.3~\mu \text{s}$ adjustment rising edge can be obtained under 0–5 kV output voltage.

A minimalistic nonlinear dynamic model, which still reflects the main aspects of the devices response to baseband pulse signals, is considered. The model is built as “black-box” and does not require knowing the structure and physical properties of the device. Since the model should reflect the exponential-type transient response, it is based on a nonlinear recursive filter. In the recursive loops the integrators are placed, because the main effect in the response of the simulated devices is the smoothing of the signal edge. The model reflects the nonlinear amplitude characteristic of the device (at the flat top of pulse), the dependence of the transient process duration on the input signal, and the nonlinear properties of the overshoot at the flat top of the pulse. We consider the realization of this model in CAD system and the methods for extracting the model parameters. The simulation error with the proposed model is 2-10% depending on the similarity of the test signal and signal at which the parameters were extracted.

Vacuum tubes such as gyrotrons and magnetrons require a specific range of high-voltage pulse rise time for their proper operation. Otherwise, unavoidable operation modes or even arcs may take place in the vacuum tubes. Hence, the capability of the adjustable output pulse rise time is very promising for pulsed power supplies when they are dedicated to vacuum tubes. This article proposes a high-voltage series stacked insulated gate bipolar transistor (IGBT) switch with rise time adjusting capability to evolve the pulsed power supply abilities. The rise time adjustment is carried out using a low-voltage ramped shape signal provided for all the IGBTs via a multi-winding transformer. In this way, the IGBTs are turned on as fast as possible with specific delays. The sequential turn on process of the IGBTs forms the output pulse rising edge. Unlike the extant strategies for controlling the turn on speed of the IGBTs, the dissipated power of the proposed method is negligible. The power associated with adjusting the output pulse rise time is recovered to the pulsed power supply using a simple and low-voltage dc/dc converter. The proper performance of the proposed structure is evaluated using simulations and experimental prototyping.

As a core component of the bucking coil helicopter transient electromagnetic (TEM) system, the current pulse inverter should agree two crucial aspects, high power and fast turn- OFF . In this article, based on the design and modeling of transmitting coil and bucking coil, a novel current inverter topology based on the double constant voltage clamping technology, which differs from the traditional single clamping technology is firstly proposed and analyzed. By using double clamping technology, both the current pulse's rising edge and falling edge are improved effectively. What's more, the turn-OFF time of the current inverter is adjustable, which is of great difference from the conventional clamping technology with nonadjustable turn-OFF time. The ground and field experiments are implemented to test the performance of the current inverter. The results of the ground test of the performance comparison with worldwide VTEM transmitter verify that it successfully converts the standard 28 V dc source from helicopter power to bipolar approximately trapezoid pulses with a peak current of 300 A and a much faster turn-OFF time than the VTEM transmitter. The results of field exploration further demonstrate that it achieves a high quality of primary field compensation and effectively improve the detection capability of the helicopter TEM surveying system.

This brief presents an auxiliary feed-forward noise cancellation (AFFNC) technique that can be applied to a generic Type-II ring oscillator (RO) PLL. The AFFNC technique uses a stand alone sub-sampling phase detector (SSPD) embedded into an alignment loop to extract and cancel noise from the RO output. Along with AFFNC, which uses one reference edge for noise extraction, a Double Sampled AFFNC (DS-AFFNC) which utilizes both the rising and falling edge of the reference for noise extraction is also presented. By using both the reference edges, higher cancellation bandwidth is achieved in DS-AFFNC. The phase-domain model developed for AFFNC and DS-AFFNC show a 2.9x and 3.9x integrated jitter reduction respectively.

The low-power chips are occurring test challenges on chip’s shmoo test on yield and performance degradation. A method for improving the performance-yield from adjusting the clock edge is presented. This work proposes a clock-edge adjusted circuit (CAC) to adjust the duty-cycle for testing multi-Vdd and multi-Vth circuits. Instead of adopting a phase-lock-loop to generate a clock with different frequencies, by external ATE cannot adjust chip-internal clock-frequency after a chip is manufactured. However, by using the proposed CAC circuit, the chip duty cycle can be trimmed. The proposed CAC generates an adjustable wide-range trigger-edge signal for the DUT chip, the duty cycles of the clock with a fixed frequency are adjusted to emulate a fast/slow chip-clock frequency. CAC can quickly push the circuit toward correct functional operation under at-speed shmoo-binning operations. It is an efficient with low-area overhead design-for–test circuit to support multi-Vdd/Vth complex designed chips. The CAC technique jointed with using Agilent-93000 automatic-test-equipment (ATE) is used to validate a four multi-Vdd/Vth Cortex-M0 processors chip. The measurements demonstrate yield improvement and accurate performance evaluation from using the CAC by ATE.

The negative pulsed downlink communication system is used to send surface control commands to the downhole rotary steering tool at thousands of meters, which is a significant part of the current rotary steering technology. At present, the transmission efficiency of negative pulsed downlink communication is very low, and only simple control commands can be transmitted in a few minutes, which limits the development of rotary steering technology with complex control functions. To improve the transmission rate of the downlink system, the downlink pulse width needs to be shortened. However, due to the influence of signal transmission characteristics, the waveform of a narrow pulse width signal will be severely distorted, which increases the difficulty of decoding the downlink signal. Therefore, a decoding method based on pattern recognition for negative pulsed downlink signal with narrow pulse width is proposed in this paper, which establishes a Euclidean distance matrix model between similar characteristic signal segments on the rising or falling edge of the downlink signal, the pulse coding timing of among the signal segment with each rising or falling edge is analyzed, the decoding and recognition of the downlink instruction are achieved, which solves the problem of large timing deviation in decoding the downlink signal with a current threshold method. The experimental results show that the method proposed in this paper can achieve accurate decoding of the 6 s pulse width downlink signal. Compared with the threshold method, it can be seen that the decoding accuracy of the method proposed in this paper can be greatly improved, and the smaller the signal pulse width, the more significant the advantage.

Power analysis attacks pose a significant threat to the security of cryptographic devices as they can reveal a secret key. Performing cryptographic operations based on a randomly varying clock (RVC) is a practical countermeasure against such attacks. The countermeasure makes it difficult to align power traces, which is a prerequisite for power analysis attacks to succeed. This paper introduces a synchronous real-time sampling (SRTS) technique as an advanced hardware-implemented approach to collect traces for a power analysis attack that negates countermeasures involving practical RVCs. By recovering the RVC, the leakage signal corresponding to the recovered clock edge is synchronously sampled in real time. We propose an analog-based hardware system implemented with two circuit blocks for SRTS operations, namely, a clock recovery block and an analog signal-processing block. The target of the power analysis attack is an Advanced Encryption Standard (AES)-128 software-implemented smart card operated at 20 MHz, which is varied in the range of 30% by the RVC countermeasure. The traces captured by the SRTS show that the suboperations of the AES encryption are distinct in contrast to the indistinguishable waveforms captured at a fixed sample rate. The results of the power analysis attack demonstrate that the correct key is successfully extracted with a high correlation coefficient at the S-box output of the AES. The proposed SRTS method improves the relative distinguishing margin by 191.4% and reduces the required number of traces to 2.75% compared with the conventional correlation power analysis attack with a fixed sample clock.

This article presents an accurate and robust method to calculate the phase offset of a reference waveform, usually produced by a digital-to-analog converter (DAC) in IEC Std 61850-9-2 calibration systems. The phase offset is defined with respect to the rising edge of a reference clock signal, locked to the Global Positioning System (GPS). The proposed method relies on the synchronous acquisition of the DAC output and the clock signal. In the complex plane, where the discrete Fourier transform (DFT) is defined, the acquired signals are processed to compensate the nonideal sampling rate and windowing. The method performance and its dependence from noise and parameters are thoroughly characterized by means of extensive numerical simulations. Two validation approaches, experimental and software-based, confirm the proposed method as a valuable and robust solution for calibration purposes.

In the Solar Insecticidal Lamps Internet of Things (SIL-loTs), when migratory insects with phototactic feature are attracted by the Solar Insecticidal Lamp (SIL) and collide with its metal mesh, the mesh releases high voltage pulse discharge. However, direct assessment of the interference from the above-generated strong electromagnetic pulse (EMP) to ZigBee-based device has not been feasible until recently. We make a design of a discharge simulation module and a data communication device, and make a modification of the SIL, both of which point to a need for more integrative approaches aimed to qualitatively explore whether the interference is existing or not during the process of discharge. Here, we present and experimentally demonstrate a key parameter, the number of microprocessors' Falling Edge Trigger (FET), for representing the existence of interference. We also use comprehensive analyses to suggest that the installing distance between SIL and ZigBee-based device is at least 25.0cm.

A fast transient response digital low dropout (LDO) regulator with a low quiescent current is proposed for power management applications in a self-powered wireless sensor system. The digital LDO incorporates both bisection method (BM) and steady-state tuning techniques to enhance the current efficiency and transient response speed. In steady-state period, the digital LDO works at steady-state mode and only one PMOS is switched at each clock edge for high accuracy and current efficiency. Once the variation of output voltage exceeds the detection boundaries, the BM mode is triggered and the required array conductance can be found in a short response time. The proposed digital LDO is fabricated using 65nm CMOS process. The measurement results show that with the load current switching between 0.1 mA and 4.5 mA, the proposed digital LDO shows a transient response time of 5.9 $\mu \text{s}$ with a maximum undershoot voltage of 118 mV at a regulated output voltage of 0.55V. The current efficiency is 99.7% and the figure of merit is 62.2 ps.

A novel method called the edge-triggered gate modulation method is proposed in this letter to decrease the voltage overshoot while maintaining high efficiency for high-power amplifiers (HPAs). In this method, the HPA is biased in high-efficiency mode, i.e., Class B/C, during the pulse-on period and switched to Class A on the rising/falling edge of the pulse. For verification, a pulsed HPA prototype operating in the X-band with an output power of ~ 1 kW is fabricated. Based on the proposed method, a relative efficiency improvement of more than 23.2% compared with conventional Class A has been achieved with the voltage overshoot thoroughly suppressed under a 1 0 / 00 duty cycle.

To improve the measurement precision of the proton magnetometer (PM), a multi-average multi-cycle frequency measurement (M-MFM) method using both rising and falling edge of square wave is proposed in this study. First, the M-MFM method using Rising-Falling edge of square wave is presented based on the multi-cycle frequency measurement (MFM) method, and the formula of frequency measurement is deduced. Then, the relative error of the proposed method is analyzed, and the proposed method is optimized by solving the minimum value of the relative error formula. Finally, the implementation process of the proposed method in STM32 is introduced. The experimental results of the frequency measurement demonstrate that the measurement precision for low SNR sine signals is significantly increased by the proposed method. The experimental results of the magnetic field measurement show that the sensitivity is about 0.11 nT/Hz1/2@0.25 Hz in the range of the geomagnetic field while the proposed method is adopted by the PM, which is better than that of the other methods and the commercial instruments.

In this paper we study photon emission in the interaction of the laser beam with an under-dense target and the attached reflecting plasma mirror. Photons are emitted due to the inverse Compton scattering when accelerated electrons interact with a reflected part of the laser pulse. The enhancement of photon generation in this configuration lies in using the laser pulse with a steep rising edge. Such a laser pulse can be obtained by the preceding interaction of the incoming laser pulse with a thin solid-density foil. Using numerical simulations we study how such a laser pulse affects photon emission. As a result of employing a laser pulse with a steep rising edge, accelerated electrons can interact directly with the most intense part of the laser pulse that enhances photon emission. This approach increases the number of created photons and improves photon beam divergence.

Conventional radiation-hardened cells of static random access memory (SRAM) are not robust enough in 28 nm technology, due to partial immunity of single-event upset (SEU) effect (Quatro-based cells) or insufficient critical charges in sensitive nodes (conventional stacked cells). The reduction of read noise margin (RNM) at the low supply voltage (VDD) confines these cells from low VDD applications. We propose a novel interleaving stacked-14T (ILS-14T) cell which prevents voltage transient from propagating to other redundancies. The ILS-14T cell can be resilient to both 0–1 and 1–0 upsets by injecting 12 mA in sensitive nodes. The critical charges of the ILS-14T cell are substantially larger than most other hardened cells at VDD from 0.3 to 0.9 V. The RNM of the ILS-14T cell is two times of most Quatro-based cells at 0.3 V VDD and larger than most cells at 0.6 and 0.9 V VDD. The area of occupation is 334% of the conventional 6T cell, which equals other 14T cells. The static–dynamic decoder array with 20%–40% area penalty and 116%–132% delay of rising edge, when compared with the conventional one, reduces the read failure rate by preventing single event transients (SETs) from propagating to unexpected word lines (WLs).

In this letter, we propose a low-complexity detection algorithm for multi-input-multi-output (MIMO) molecular communication (MC). By virtue of a rising edge in received signals, this detection algorithm is capable of recovering the information bits in MIMO-MC systems. From an engineering point of view, this algorithm can significantly eliminate the impact of inter-symbol interference. It has also proven itself useful for dealing with the received signal from the MIMO-MC testbed with sufficiently low bit error rate (BER) or even an error-free performance. Moreover, in terms of BER performance, this algorithm outperforms existing detection algorithms for single-input single-output MC systems.

The IP-core for QR-code generation, which supports codes of the first version and the M-type level of correction (allows to recover information from damaged up to 15% code image) is developed. Based on this IP-core and the DE1-SoC development board, containing the Cyclone V FPGA chip, the real QR-code generation device was implemented. The device uses the PS/2 interface to enter text data that should be encoded in the QR-code and output the result (generated code) on a VGA monitor as an image. The suggested device has the following structure: the control module, the IP-core for QR-code generation, and I/O modules. The control module performs the general device management and implemented as the state machine, which has the following states: reset and memory cleaning, read the text that should be encoded from the keyboard, create the main part of the QR-code, create correction data, combine the correction data with the main part of the QR-code, transform the result into a 21x21 pixel matrix and displaying the code on the screen. The input module reads the keyboard signals (synchronization and data signal) and converts them into the ASCII codes. To do this, on each falling edge of the synchronization signal the values of the data signal are registered and propagated to the 8-bit bus. Since the keyboard may have a contact bounce, this module additionally filters the received data using the delay filtering. The output module is the VGA controller that simply generates the necessary clock signals for the proper VGA monitor functioning. After the QR-code is generated, its matrix is enlarged and passed to the VGA controller. Also, in parallel with that, the text, which was encoded in the code, is printed on the display. The IP block for QR-code generation consists of three submodules. The first one receives a text in ASCII format (now only 14 characters are supported) and generates the primary sequence of data to be encrypted in the code. The second submodule calculates the correction data using the Reed-Solomon algorithm. To use this algorithm, the additional array is reserved to store the correction data. This array is filled with special information, depending on the level of correction and the code version number. The algorithm also requires tables of the forward and reverse Galois fields, which are precalculated and stored in the submodule’s ROM. The third module generates the matrix itself: it places the alignment patterns, the information of the used type of mask, level of correction, and adds timing patterns. After that, the mask superimposed on the data generated by the previous module, and the result is copied to the code’s matrix in the required order.

Low propagation delay time is essential for SiC drivers at high frequency. The propagation delay time of the commercial parts is normally over 100 ns. A signal isolation circuit and a level shifting circuit are proposed and applied in SiC drivers with minimum propagation delay time. The narrow edge signals of the input pulsewidth modulation (PWM) signal are extracted by nondelay RC differential circuits in the control side and demodulated by an RS flip-flop in the drive side so that only two low-profile transformers are used for low-delay signal isolation. A two-stage isolated auxiliary power supply without linear optocouplers is proposed in order to realize wide input voltage range and wide operation temperature range. Wide input voltage range is achieved by forward- feedback control. The experimental results verify the proposed driver advantages. The propagation delay time at 400 kHz is 49.6 ns for the rising edge and 18.4 ns for the falling edge, which are reduced by over 50% compared with the commercial parts. The prototype is tested under the ambient temperature of 85 °C with the 9–18-V input auxiliary power supply. Considering the temperature rise of 28 °C, the operation temperature of the power supply is 113 °C.

Time division multiplexing (TDM) uses a digital flux-locked loop (DFLL) to linearize each first-stage SQUID amplifier. Presently, the dynamic range of our TDM systems is limited by the use of a proportional-integral controller to maintain the DFLL. In this paper, we use simulations to assess the improvements possible with a predictive control algorithm that anticipates rapid changes in transition-edge sensor current during the rising edge of an X-ray pulse. We calculate that the predictive control algorithm can improve our TDM architecture’s dynamic range by 35%. This significant increase in multiplexing capabilities could be used to read out higher-energy X-rays, reduce readout noise, increase multiplexing factors, or reduce SQUID power output.

In complex terrain, semi-airborne transient electromagnetic surveying can effectively solve the detailed exploration problems to replace ground manual operation. This method has the advantages of high efficiency, deep exploration depth, and high signal-to-noise ratio. As the core component of the system, the constant-current transmission converter determines the primary field source of the surveying system. High-accurate and stable-output electromagnetic transmission technology is the key issues of the surveying equipment development. In this paper, the converter circuit topology is designed in detail and a novel model reference adaptive proportional-integral control algorithm is put forward. The rising overshoot of current is eliminated and falling edge is linear. Finally, the 20-kW high-power transmitting instrument has been completed and used for field experiments. A large number of experimental results show that the transmitting instrument can achieve high-power constant-current emission, stable output, and good dynamic performance. And the steady-state accuracy is better than the traditional transmitter. The converter successfully improved the semi-airborne transient electromagnetic system detection capability and achieved satisfactory results in field experiments.

This paper explores an ultrahigh dimming frequency Light-Emitting Diode (LED) pulse width modulation (PWM) shunt dimming driver that achieves the full-range dimming. Firstly, the dimming frequency is improved to 20kHz for avoiding flicker and audible noise in high dimming requirements application, such as film and television shooting. Secondly, this paper reduces dimming ratio loss at ultrahigh dimming frequency by removing output capacitor. As a result, given 1% dimming ratio is achieved. Subsequently, for improving LED current square waveform at ultrahigh dimming frequency, it is necessary to suppress parasitic oscillation at the falling edge in LED current. Therefore, this paper proposes a method which connects a fast recovery diode with LED in series. In such way, parasitic oscillation at the falling edge in LED current is suppressed. Meanwhile, linear dimming performance is improved such as dimming linearity of low ratio and circuit reliability. Finally, a 120 W experimental prototype is built to drive an LED array comprising 9 LEDs in parallel and 15 LEDs in series. The switching frequency and dimming frequency of prototype are 500 kHz and 20 kHz, respectively. In addition, it achieves full dimming range of 1% to 99.99%.

Inductive pulsed power supply (IPPS) is considered as an alternative to capacitive one due to its higher energy density. An opening switch is necessary for an IPPS because it interrupts the charging circuit and transfers the stored energy to the load. A major technical challenge inherent to the IPPS is the overvoltage across the opening switch, i.e., the open-circuit voltage. Moreover, obtaining a larger current, especially with a steeper rising edge, will further increase the open-circuit voltage. A novel IPPS based on a three-winding pulse transformer, consisting of two primary windings and one secondary winding, is presented in this article to improve the output current and reduce the open-circuit voltage. The two primary inductors adopted a parallel switching scheme, namely, series charging and parallel discharging. Its working principle is analyzed first in detail. The theoretical analysis and simulation results have verified the superiority of the novel IPPS in improving the output current and reducing the open-circuit voltage.

This paper presents a novel symmetrical phase frequency detector (PFD) sensitive to the falling edge of input clocks. Notably, the new PFD has an open-loop structure and no reset path, since UP and DN (outputs of the PFD) are never allowed to reach logic high simultaneously. Hence, the blind zone is completely eliminated in this case. Dead zone has been reduced to a great extent about 68 fs. Meanwhile, the proposed PFD is reliably capable of detecting from 0° to 360°, even 180° phase difference between clocks correctly by itself. The PFD has been simulated using the H-SPICE level 49 of a standard 0.18 μm CMOS process. It has been simulated in different conditions. Its maximum operating frequency at the worst-case conditions varied from 1.4 to 4.7 GHz at different supply voltages varied from 1.2 to 2.4 V. It can operate from very low frequencies up to 4.3 GHz at the power supply of 1.8 V, reliably. It can be used in high-speed and low-power applications. The new PFD consumes power within a range from 11.79 to 478.8 μW when operating at 50 MHz and 4.3 GHz, respectively. It has also been simulated in different process corners. Using the minimum size devices leads to a compact layout and die size of about 124.3 μm2.

The use of energy efficient equipment in household situations is increasing. Because of the non-linear and time-invariant behavior of such equipment, conducted electromagnetic interference problems arise. For instance, dimmed light equipment and a speed controlled water pump resulted in interference with static energy meters in previous studies. And the large crest factor, short pulse duration, and fast rising slope of the drawn current were correlated with the interference. Next to this, no strict regulations apply for the emission of dimmers that control the intensity or speed of a load. Therefore, this paper researches the current emissions of dimmed lighting equipment, which is providing situations that are representative to be used in low-voltage networks. This includes different lighting technologies and different dimming principles, i.e. rising and falling edge dimming. It was found that falling edge dimming resulted in the lowest conducted emissions.

The development of new technologies in the field of power electronics implies higher switching frequencies. Such frequencies are associated with higher transient voltages. Higher voltages mean stress on the insulation material. As result of this increased load, partial discharge (PD) probability can be increased, which may push the insulation material to its limits. Therefore, it is of high importance to recognize PDs. It is already known that PDs occur not only on the rising edge, but also in the steady state of a voltage pulse. However, double PDs may occur, too. Using a special test arrangement, it is possible to detect also weak PD activity, to localize the time instant and to determine changes in voltage and current. These changes are characterized e.g. by a sudden drop in pulse voltage.

Unmanned Aerial Vehicle (UAV) has limited computing power, but requires high accuracy and low latency in the visual object detection for critical UAV missions, such as infrastructure inspection. It may need highly complex machine learning algorithms with the demand of extensive computing power. With the rising edge computing technology, the heavily-loaded object detection tasks can be offloaded to edge computing systems. To enable such edge-based object detection with low overhead, we discover that it is critical to minimize the response time of the detection while maximizing the frequency of detected image frames. In this paper, we identify three key research challenges, conduct an experimental case study to show that current edge-based naive solutions cannot achieve the above goal, and finally point out major ideas for potential solutions.

For a better understanding on what is causing static energy meter misreadings different current waveforms with falling and rising edges have been compared. Falling edge dimming showed higher static energy meter deviations due to the larger rate of change in the current, $\vert \mathrm{d}I / \mathrm{d}t\vert$ , compared to the rising edge dimming. The difference in $\vert dI / dt\vert$ is due to the asymmetry inherent in the semiconductors used. No specific difference in static energy meter deviation was found due to the polarity of the $\mathrm{d}I / \mathrm{d}t$ . Faling edges in the first quarter of the sine wave resulted in an overestimation of the consumed power just as rising edges in the second quarter. Rising edges in the first quarter and falling edges in the second however showed an underestimation of the consumed power. The underestimation seems to compensate the overestimation when using complementary waveforms.

To achieve high-precision time synchronization among multiple systems, a synchronization method based on Global Position System(GPS) 1 pulse per second(1 PPS) is proposed. The 1 PPS signal of GPS is used as the synchronization reference signal to complete the synchronization between multiple systems. Firstly, working commands are sent to all systems through the wireless module in the rising edge of 1 PPS. Then in the next rising edge of 1 PPS, all systems convention synchronization starts working, eventually achieving high-precision synchronization of multiple systems. In the key synchronization implementation, the method completely relies on logical circuit, and without processor participation, which greatly improves the synchronization accuracy of the system. Meanwhile, sending a working command on the rising edge of 1 PPS eliminates the cross-second error caused by the communication delay of wireless module, and the communication delay of wireless module can be completely ignored. The experiment restults show that the synchronization error standard deviation of this method is 51.94ns, which has extremely high synchronization performance and can be widely used in military and industrial fields.

This paper deals with a well-known problem of the transient DC-bias current occurring during a phase shift transition in dual active bridge (DAB) DC/DC converters. This phenomenon, if not compensated, can cause damage to the converter or deteriorate its performance. One aim of this paper is to present a solution which allows for the elimination of the undesired transient DC-bias component in current waveforms. This solution is the dual rising edge shift (DRES) compensation algorithm. It provides a very simple implementation and fast settling time within the first half of a switching period. Moreover, the solution is independent on any measurements or system parameter values. It is based on the double-sided single phase shift (DSSPS) modulation, which is described in detail along with a converter model in steady-state. Then, the mechanisms leading to the transient DC-bias are explained, and the compensation algorithm is derived. The performance of the algorithm has been tested using a laboratory prototype. A comprehensive set of tests, involving rapid step changes in power flow and frequency sweep, are provided. Finally, the features of the proposed algorithm are briefly discussed.

A type of high-voltage pulse source technology generating double-exponential waveform pulse group was introduced. In this approach, the pulse interval could be adjusted with the step length of 100 μs, and the amplitude would reach up to 35 kV. This pulse source could be used to test the sensitivity of electric vehicle (EV) piles under electrical fast transient (EFT) interference. The theory of obtaining double-exponential wave and its generating circuit was analyzed, and then the influencing factors of the rising edge were expounded. A method of pulse insertion was adopted to generate a fast transient pulse group due to the limitation of the repeated operating frequency of switching devices. This method could be summarized as a common load fed by several parallel pulse sources, which were controlled and triggered in time sequence. Thus, a set of timing pulse could be obtained from the load ending. The feasibility of this method was also demonstrated. The electromagnetic interference cannot be avoidable because the load was fed by different timing sources. The high-voltage pulse generated initially causes the latter sources to be false-triggered with serious influence to the entire system. The interference generated by the couple circuit composed by distributed parameters, such as distributed capacitance and inductance, was also analyzed. A coupled model was established, analyzed, and simulated to prove the existence of the conducted interference and false triggering for other sources. The measure of conducted interference suppression was also presented. A set of experiments was carried out to show that different numbers of double-exponential pulse groups with different time intervals could be obtained.

The foreseen incremental luminosity for near-future high-energy physics experiments demands evolution for the read-out electronics in terms of event data-rate. However, the filtering necessary to reject noise and meet the signal-to-noise-ratio requirements imposes a restriction on the operational speed of the conventional read-out electronics. The stringent trade-off between signal-to-noise-ratio and the event data-rate originates from the time-invariant behavior of the conventional systems. In this paper, the cases of time-variant systems are addressed, studying a benchmark with the RC-CR shaping function used in time-over-threshold methods. It was demonstrated that the time-variant systems enable a higher data-rate for the given noise performance. Moreover, taking advantage of time-variant systems, the proposed rising-edge method enables further data-rate enhancement with respect to the traditional time-over-threshold technique by reading the data from the rising edge of the analog output waveform. A comparison between the conventional time-invariant time-over-threshold technique, its time-variant equivalent and rising-edge method confirms the better performance of the latter one in terms of data-rate enhancement for a target noise performance. Moreover, design challenges for time-variant systems are briefly discussed, considering the ATLAS Monitored Drift Tube detector as a design case.

Up to now, the rising edge of the upconversion process does not receive due attention. Herein, a demonstration utilizing the feature of the rising edge to practically detect the linear-velocity of an object is presented. Typically, upconversion processes with different numbers of participant photons would exhibit diversity in the rising edge. On this account, when the emitter is moving, the emission intensity ratio of different multiphoton processes will vary with changing linear-velocity, which enables accurate speed detection through spectral analysis. To illustrate this principle, in this work, the modeling and numerical simulation were first performed, and then experimental demonstration was carried out in which core-shell upconversion nanocrystals were elaborately designed and fabricated as the speed sensing probe to calibrate the speed of a homemade turnplate. It is believed that the present work will exploit a novel speed sensing method and find a new application for lanthanide-doped upconversion materials.

A novel high-frequency isolated three-phase voltage-fed semi-dual active bridge dc–dc converter is proposed for unidirectional power flow with wide input variations and high voltage interface. A varying operating mode control independently implemented by phase shift and duty cycle control is subsequently raised to handle the stability and improve the conversion efficiency of the converter under the light load conditions. A variety of different operating modes are illustrated and compared in detail. The power expressions and the root mean square expressions of the leakage inductor current of different modes are derived and the optimal modes are consequently selected. The gating signal falling edge compensation of secondary side switches is implemented to further improve the conversion efficiency. The zero voltage switching conditions based on current polarity is also derived. A 1.6 kW prototype was built to verify the effectiveness of the proposed topology and control strategy. The experimental results show that the proposed converter using the proposed control strategy can achieve stability throughout the input and load variations. Moreover, seamless transition can also be achieved, the dynamic performance is good, and high conversion efficiency can be guaranteed.

Free-field shock wave (FSW) in explosion monitored by electrical wired system with piezoelectric pressure probe sensor (PPPS) has been widely investigated and applied. However, it is very difficult to accomplish accurate pressure measurement for shock wave (SW) due to steep rising edge, short pulse width characteristics of peak pressure signal and different incident angle of SW to sensor. This paper aims to find an approach to integrate the mounting structure with PPPS for the FSW testing more accurately. First, we design two mounting structures namely disc structure and wedge structure for sensor installation and evaluate the impacts of different incident angles of SW on PPPS under two installation structures by simulation. Furthermore, the pressure signals are obtained by two measurement system relying on commercial PPPSs from PCB and Kistler Co., Ltd., respectively, and we reconstruct the overpressure waveform by wired measurement system. The results from the experiment demonstrate that the reconstructed waveforms have good uniformities. Depending on the simulation model and experiment data, this paper is conducted to provide new insights and approach into how the integration of mounting structure and PPPS is implemented for acquiring dynamic parameters accurately, and further giving advisable reference to various sensors and structures applied in more FSW monitoring scenarios.

An equivalent circuit method (ECM) is proposed for the design of multilayer frequency-selective surfaces (FSSs). In contrast to the existing ECMs that were developed mainly for the analysis of the properties of a given FSS, the presented ECM aims at providing the initial design parameters of an FSS from the desired frequency response. In this method, four types of basic FSS structures are used as the building blocks to construct the multilayer FSSs, and their surface impedances in both the normal- and the oblique-incidence situations are studied in detail in order to achieve more accurate equivalent circuit (EC) representation of the entire FSS. For a general FSS design with expected frequency response, the EC parameters and the geometrical sizes of the required basic building blocks can be synthesized from a few typical S-parameter (S11/S12) samplings of the response curves via a simple least-square curve-fitting process. The effectiveness and accuracy of the method are shown by the designs of a band-pass FSS with steep falling edge and a miniaturized band-pass FSS with out-of-band absorption. The prototype of one design is fabricated, and the measured frequency response agrees well with the numerical results of the ECM and the full-wave simulations.

Real-time detection of scattering intensity and the time-resolved imaging technique were combined to reveal the development sequence of laser damage. The real-time detection of scattering intensity can reveal when the damage occurs and grows rapidly, indicated by the increase of scattering intensity during the entire irradiation with picosecond time resolution. Furthermore, the time-resolved imaging technique was applied to observe detailed modifications of the specific moments when the scattering intensity exhibits a sudden increase. Three characteristic moments during a damage event induced by a nanosecond pulse at 355 nm in thick fused silica were captured by the real-time detection of scattering intensity. These three moments were located at the rising edge of the pulse, near the peak of the pulse, and near the end of the pulse. Combined with time-resolved images captured near these three moments, the results indicate that damage of the filamentary tail appeared at the rising edge of the pulse. Further, the head region of the filamentary damage developed near the peak of the pulse. The whole damaged area grew rapidly near the end of the pulse. The underlying physical mechanisms around the three characteristic moments are discussed to interpret the development sequence of laser damage.

We propose a hybrid time-of-flight/phase-shift (TOF/phase-shift) method using a falling-edge radio-frequency-modulated (RF-modulated) pulsed laser for absolute distance measurement. The principle of the new hybrid TOF/phase-shift technique is based on the use of an RF-modulated pulse to benefit from both the long unambiguous distance of the pulsed TOF method and the accuracy of the RF phase-shift measurement. The RF-modulated pulse is obtained using a pulsed frequency-shifted amplifying loop coupled to a single-frequency laser. The RF modulation depth and pulse waveform properties of the optical fiber loop are investigated. Then, the fully fibered RF-modulated source is applied to a laboratory distance measurement. We show experimentally that the hybrid TOF/phase-shift method is a promising technique that achieves 3 mm precision in the 1.5 km measurement range (in fiber), corresponding to a relative precision of 2 × 10−6.