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Electronic–photonic computing systems offer immense potential in energy-efficient artificial intelligence (AI) acceleration tasks due to the superior computing speed and efficiency of optics, especially for real-time, low-energy deep neural network inference tasks on resource-restricted edge platforms. However, current optical neural accelerators based on foundry-available devices and conventional system architecture still encounter a performance gap compared to highly customized electronic counterparts. To bridge the performance gap due to lack of domain specialization, we present a time-multiplexed dynamic photonic tensor accelerator, dubbed TeMPO , with cross-layer device/circuit/architecture customization. At the device level, we present foundry-compatible, customized photonic devices, including a slow-light electro-optic modulator with experimental demonstration, optical splitters, and phase shifters that significantly reduce the footprint and power in input encoding and dot-product calculation. At the circuit level, partial products are hierarchically accumulated via parallel photocurrent aggregation, lightweight capacitive temporal integration, and sequential digital summation, considerably relieving the analog-to-digital conversion bottleneck. We also employ a multi-tile, multi-core architecture to maximize hardware sharing for higher efficiency. Across diverse edge AI workloads, TeMPO delivers digital-comparable task accuracy with superior quantization/noise tolerance. We achieve a 368.6 TOPS peak performance, 22.3 TOPS/W energy efficiency, and 1.2 TOPS/mm2 compute density, pushing the Pareto frontier in edge AI hardware. This work signifies the power of cross-layer co-design and domain-specific customization, paving the way for future electronic–photonic accelerators with even greater performance and efficiency. [ABSTRACT FROM AUTHOR]

Indoor wireless systems at 60 GHz provide much higher throughput than today's solutions but need more closely spaced access points. Radio-over-Fiber advancements are a promising solution for the signal distribution. We propose a broadband IF-over-Fiber architecture comprised of miniaturized electronic components for quadrature modulation and upconversion. The 60 GHz wireless generation is realized by transmitting at intermediate frequency (IF) at 10 GHz over single mode fiber (SMF) and upconversion at the base station (BS) front-end with low-cost electronic components on printed circuit board (PCB). The central station (CS) includes an electronic IQ modulator for the provision of multi-Gbps quadrature data modulation formats and successively increase the spectral efficiency of the wirelessly transmitted data. The BS front-end comprises of the 60 GHz upconverter and a 60 GHz planar 2 × 2 microstrip antenna array. The 10 GHz IF carrier allows an optical transmission with higher spectral efficiency in optical domain, as well as it is less susceptible to dispersion induced power fading inherent in optical fiber. The optical fronthaul link of the 10 GHz IF signal modulated with up to 2 Gbps payload data over SMF lengths of 2 km, 12.8 km and 25.6 km has been studied. The system analysis is made with respect to error vector magnitude (EVM), eye and constellation diagrams. The recovered QPSK data has signal-to-noise of 14 dB corresponding to EVM of 20% for transmission over 25.6 km SMF. [ABSTRACT FROM AUTHOR]

This paper presents an innovative general structure for a single-loop Sigma-Delta (Σ Δ) modulator that combines low-distortion and noise-coupled techniques to achieve high-resolution for low-power applications. The low-distortion technique adjusts the signal transfer function of the proposed structure to unity, while the noise-coupled technique enhances the order of quantization noise-shaping at the modulator output. These techniques were incorporated into the design to increase the modulator order without requiring additional operational amplifiers during its circuit implementation, resulting in a low-power modulator compared to similar structures. To reduce the number of required amplifiers, a second-order infinite impulse response (IIR) filter was used in the modulator loop filter, in place of two integrators. To assess the proposed structure's performance, a third-order modulator sample was implemented and simulated for speech recognition applications, specifically, digital hearing aids, using 180 nm complementary metal oxide semiconductor (CMOS) technology. The results indicate that for a third structure with a sampling rate of 64, an input sine signal of −6 dBFS and a sampling frequency of 2.56 MHz, the signal to noise plus distortion (SNDR) was 81.9 dB, and the dynamic range (DR) was 88 dB for a 20 KHz bandwidth. The modulator's power consumption was 126.9 μ W. Circuit and system-level simulations demonstrate the effectiveness of the proposed method. [ABSTRACT FROM AUTHOR]

This paper presents advancements in the performance of digital phase-locked loop (DPLL)s, with a special focus on addressing the issue of required gain calibration in the time-to-digital converter (TDC) within phase-domain DPLL structures. Phase-domain DPLLs are preferred for their simplicity in implementation and for eliminating the delta–sigma modulator (DSM) noise inherent in conventional fractional-N designs. However, this advantage is countered by the critical need to calibrate the gain of the TDC. The previously proposed dual-interpolated TDC(DI-TDC) was proposed as a solution to this problem, but strong spurs were still generated due to the TDC resolution, which easily became non-uniform due to PVT variation, degrading performance. To overcome these problems, this work proposes a DPLL with a new calibration system that ensures consistent TDC resolution matching the period of the digitally controlled oscillator (DCO) and operating in both the foreground and background, thereby maintaining consistent performance despite PVT variations. This study proposes a DPLL using a calibrated dual-interpolated TDC that effectively compensates for PVT variations and improves the stability and performance of the DPLL. The PLL was fabricated in a 28-nm CMOS process with an active area of only 0.019 mm2, achieving an integrated phase noise (IPN) performance of −17.5 dBc, integrated from 10 kHz to 10 MHz at a PLL output of 570 MHz and −20.5 dBc at 1.1 GHz. This PLL operates within an output frequency range of 475 MHz to 1.1 GHz. Under typical operating conditions, it consumes only 930 µW with a 1.0 V supply. [ABSTRACT FROM AUTHOR]

Electric vehicle systems and smart grid systems are setting stringent development targets to respond to global trends in energy saving, carbon reduction, and sustainable environmental development. In the field of batteries, there has been extensive discussion on the estimation of battery charge. In battery management systems (BMSs) and charging/discharging systems, the accuracy of the measurement of battery physical parameters is critical, as it directly affects the system, alongside the algorithm's estimation and error correction. Therefore, this paper proposes incorporating a low-power continuous-time delta-sigma analogue-to-digital converter into a battery measurement system to support deep learning algorithms for battery state estimation. This approach aims to maintain the accuracy of battery state estimation while reducing latency and overall system power consumption. Implemented using the UMC 0.18 μm CMOS 1P6M process, the proposed design achieves a measured signal-to-noise distortion ratio (SNDR) of 78.42 dB, an effective number of bits (ENOB) of 12.73 bits, and a power consumption of approximately 15.97 μW. The chip layout area is 0.67 mm × 0.56 mm. By applying delta-sigma modulators to energy management systems, this solution aims to increase the total number of battery monitoring units while reducing overall power consumption and construction costs. [ABSTRACT FROM AUTHOR]

The present study investigates the identification of novel heat shock protein‐90 (HSP90) inhibitors‐modulators employing de novo drug design methodologies. Precisely, a machine learning (ML) assisted de novo design tool, REINVENT4, was employed for generating novel molecules against a given set of known HSP90 inhibitors. Further, a series of cheminformatics analyses were undertaken to assess pharmacokinetic properties, evaluate binding affinity using docking, and predict absolute binding affinity using the KDeep tool to reduce the chemical space. Finally, three novel benzimidazole‐based drug‐like candidates viz. IM1, IM2, and IM3 were selected as potent inhibitors‐modulators for HSP90 protein. Docking‐based binding affinity of IM1, IM2, and IM3 was obtained as −11.30, −11.50, and −11.20 kcal/mol, respectively. Moreover, all identified protein‐ligand complex dynamic behavior has been extensively assessed through MD simulation for a 100 ns span, highlighting overall interaction stability and conformational rearrangements for protein bound with all selected compounds. The MM‐GBSA‐based binding free energy estimation for each complex demonstrated the superiority of identified compounds, as found to be −43.54, −38.34, and −25.50 kcal/mol for IM1, IM2, and IM3. Collectively, pharmacokinetics and drug‐like profile assessment of identified compounds, along with simulation trajectories, explained the potentiality of the compounds for modulating the activity of the HSP90. [ABSTRACT FROM AUTHOR]

Due to the ability of optical modulators to achieve rapid modulation of optical signals, meeting the demands of high-speed data transmission, modulators based on different novel nanomaterials have become one of the research hotspots over the past dacade. Recently, TiN/Ti3C2 heterojunction exhibits highly efficient thermo-optic performance and extremely strong stability. Therefore, we have demonstrated an all-optical modulator based on the principle of Michelson interference and the thermo-optic effect in this paper. The modulator employs a TiN/Ti3C2 heterojunction-coated microfiber (THM) and further demonstrates its ability to generate phase shifts through an ASE light source. The modulator, with a phase shift slope of 0.025π/mW, can also convert the phase shifts of signal light into amplitude modulation through Michelson interference. The fixed signal light wavelength is 1552.09 nm, and the modulation depth is stable at about 26.4 dB within a wavelength detuning range of −10 to 6 nm; The waveforms of signal light at modulation rates of 500 Hz, 1000 Hz, 2000 Hz, and 3000 Hz were tested, and a 3 dB modulation bandwidth of 2 kHz was measured. The all-optical modulator based on THM has the advantages of high efficiency and stability and has broad application prospects in the fields of all-optical signal processing and high-speed optical communication. [ABSTRACT FROM AUTHOR]

Summary: Compared to the independent application of chopper stabilization or correlated double sampling (CDS), this paper proposed a 2nd‐order cascade of integrators with feedforward delta–sigma modulator (DSM) utilizing an innovatively synthetic technique of chopper‐integrator within CDS at 1st stage for reducing the flicker noise and DC offset cancelation from about 9.5 mV to −4.4 μV ± 115.6 μV (δ). On the regard of further enhancing the noise suppression and mitigating the nonlinearities of capacitor mismatch, instead of applying the dynamic elements randomization (DER) to the nonlinear correction of DAC under multi‐bits quantizer, here the operation of 3‐bits DER with scrambler has been intelligently employed on the 2nd integrators' sampling capacitors to gain the 2nd noise‐shaping characteristic in spite of 1‐bit quantizer. The noise floor could be theoretically scaled down by −16.1 dB at input frequency of 10 kHz within the limited bandwidth of 100 kHz. The prototype DSM was manufactured in 180‐nm BCD process with an active area of 0.2625 mm2 and achieves the SNDR‐based Schreier figure‐of‐merit (FoMS) of 144 dB and Walden figure‐of‐merit (FoMW) of 25.96 pJ/conv under a 3.3 V supply at 10 kHz working frequency. [ABSTRACT FROM AUTHOR]

This paper addresses the design of a CMOS modulator to control two quantum bits. The proposed architecture offers several advantages that are addressed and discussed in this paper. The proposed architecture is investigated through both mathematical modeling and Verilog simulations. Moreover, the circuit was designed using the cryogenic Design Kit of the 130 nm SiGe BiCMOS technology of the IHP foundry. The observed agreement between the modeling, Verilog, and transistor-level simulations proves the physical feasibility of the proposed architecture. [ABSTRACT FROM AUTHOR]

Cytosolic Glycerol-3-phosphate dehydrogenase 1 (GPD1, EC 1.1.1.8) plays a pivotal role in regulating the Embden-Meyerhof glucose glycolysis pathway (E-M pathway), as well as in conditions such as Huntington's disease, cancer, and its potential role as a specific marker for Dormant Glioma Stem Cells. In this study, we conducted virtual screening using the ZINC database (http://zinc.docking.org/) and the GPD1 structure to identify potential GPD1 modulators. The investigation involved screening active candidate ligands using ADMET (Absorption, Distribution, Metabolism, Excretion, Toxicity) parameters, combined with molecular docking, pose analysis, and interaction analysis based on Lipinski and Veber criteria. Subsequently, the top 10 ligands were subjected to 200 ns all-atom molecular dynamics (M.D.) simulations, and binding free energies were calculated. The findings revealed that specific residues, namely TRP14, PRO94, LYS120, ASN151, THR264, ASP260, and GLN298, played a crucial role in ensuring system stability. Furthermore, through a comprehensive analysis involving molecular docking, molecular M.D., and DeLA-Drug, we identified 10 promising small molecules. These molecules represent potential lead compounds for developing effective therapeutics targeting GPD1-associated diseases, thereby contributing to a deeper understanding of GPD1-associated mechanisms. This study's significance lies in identifying key residues associated with GPD1 and discovering valuable small molecules, providing a foundation for further research and development. [ABSTRACT FROM AUTHOR]

Objective: Sphingosine-1-phosphate receptor (S1PR) modulators have recently attracted increasing attention for the treatment of multiple sclerosis (MS). Despite their preference in the clinic, multiple adverse events (AEs) continue to be reported every year. This study aimed to investigate the potential AEs as well as related important medical events (IMEs) signal associated with S1PR modulators, including fingolimod, siponimod and ozanimod in a real-world study using the FDA Adverse Event Reporting System (FAERS) database. Methods: All data were collected from the FAERS database, spanning from the fourth quarter of 2010(2010Q4) to the second quarter of 2023 (2023Q2). Potential AE and IME signals of S1PR modulators were identified based on a disproportionality analysis using the reporting odds ratio (ROR), proportional reporting ratio (PRR), and the bayesian confidence propagation neural network of information components (IC). Results: Overall, 276,436 reports of fingolimod, 20,972 reports of siponimod and 10,742 reports of ozanimod were analyzed from the FAERS database. Among reports, females were more prone to develop AEs (73.71% for females vs. 23.21% for males), and more than 50% of patients suffered from AEs were between 18 and 64 years. Subsequently, we investigated the top 20 AEs associated with the signal strength of S1PR modulators at the preferred term (PT) level, and identified 31 (8 vs. 11 vs. 12, respectively) unlabeled risk signals such as thrombosis, uterine disorder and reproductive system and breast disorders. Furthermore, we discovered that the S1PR modulator reported variations in the possible IMEs, and that the IMEs associated with ocular events were reported frequently. It's interesting to note that infection and malignancy are prominent signals with both fingolimod and siponimod in the top 20 PTs related to mortality reports. Conclusion: The present investigation highlights the possible safety risks associated with S1PR modulators. The majority of AEs are generally consistent with previous studies and are mentioned in the prescribing instructions, however, several unexpected AE signals have also been observed. Ozanimod showed the lowest signal intensity and a better safety profile than the other S1PR modulators. Due to the short marketing time of drugs and the limitations of spontaneous reporting database, further research is required to identify potential AEs related to S1PR modulators. [ABSTRACT FROM AUTHOR]

In work, a new method of optical microwave signal generation with frequency 18-tupling using three parallel polarization modulators (PolMs) was proposed, in which the PolM is integrated through a polarization beam splitter, two phase modulators, an electrical phase shifter, and a polarization beam coupler. To generate a frequency 18-tupling millimeter-wave (mm-wave) signal, the polarization controller must first be employed to bring out linearly polarized light. Next, the linearly polarized light is faded into three PolMs to be modulated by a radio frequency signal, which can achieve multi-frequency optical sidebands. Last, controlling a polarizer to cancel unwanted optical sidebands to obtain ±9th optical sidebands is used to generate an 18-tupling mmwave signal. We have conducted detailed mathematical formula derivation and computer simulation for the scheme. The results show that the scheme can be experimentally realized and accurate enough with the performance of the signal: the optical sideband suppression ratio can reach 48.02 dB, and the radio frequency spurious suppression ratio can reach 42.25 dB, almost equal to the theoretical model. [ABSTRACT FROM AUTHOR]

In this paper, we have proposed and demonstrated a 100 Gbps data transmission system over hybrid single mode fiber (SMF)-free space optics (FSO) link using optical comb lines in wavelength-division-multiplexing technique. A continuous wave laser, two dual drive Mach-Zehnder modulators and four electrical attenuators are employed to generate optical frequency comb lines (OFCL). The OFCL generator generates 52 comb lines by optimizing biasing voltages. The OFCL lines with a side mode suppression ratio of ∼ 50dB and flatness ∼∼ 0.01dB are generated and used as an optical carrier in the proposed system. The performance of the system is investigated in different weather conditions, such as clear weather, hazy weather, heavy rain, light fog, moderate fog, and heavy fog. [ABSTRACT FROM AUTHOR]

As the current mainstream high-precision ADC architecture, sigma-delta ADC is extensively employed in a wide range of domains and applications. This paper presents the design of a highly efficient cascaded digital decimation filter for sigma-delta ADCs, emphasizing the suppression of high folding band noise and the achievement of a flat passband. Additionally, this study addresses the critical balance between filter performance and power consumption. An inserting zero (IZ) filter is incorporated into a cascaded integrator comb (CIC) filter to enhance aliasing suppression. The IZ filter and compensation filter are optimized using the particle swarm optimization (PSO) algorithm to achieve greater noise attenuation and smaller passband ripple. The designed filter achieves a noise attenuation of 93.4 dB in the folding band and exhibits an overall passband ripple of 0.0477 dB within a bandwidth of 20 KHz. To decrease the power consumption in the filter design, polyphase decomposition has been applied. The filter structure is implemented on an FPGA, processing a 5-bit stream from a 64-times oversampling rate and third-order sigma-delta modulator. The signal-to-noise ratio (SNR) of the output signal reaches 91.7 dB. For ASIC design, the filter utilizes 180 nm CMOS technology with a power consumption of 0.217 mW and occupies a layout area of 0.72 mm2. The post-layout simulation result indicates that the SNR remains at 91.7 dB. [ABSTRACT FROM AUTHOR]

The output of a Digital Delta-Sigma Modulator (DDSM) is always a periodic signal and the input is constant. The frequency synthesizer is commonly used due to its flexibility and convenient frequency adjustment. This paper presents a new method to implement random dither in MASH 1-1-1 modulator. There are two different methods to remove unwanted tones from the MASH modulator output, which are deterministic and random. Deterministic methods include setting the initial conditions of the internal registers, using the first-module quantizer, and the HK-MASH structure. On the other hand, the random method involves applying a random dither signal to the circuit in different ways to eliminate the periodic behavior of the output string. Deterministic methods are not useful for most practical applications. In most practical applications, dither signal is a suitable method. In this article, the disadvantages of different dither methods will be investigated and a new vibration method for MASH sigma-delta modulators for use in fractional frequency synthesizers will be presented. [ABSTRACT FROM AUTHOR]

A Sigma-Delta modulator (SDM) realized with a fully differential third-order single-loop cascaded integrator feedforward (CIFF) architecture is proposed. A pair of low-frequency chopper switches are nested outside the chopper amplifier to further reduce the residual offset voltage. To reduce the power consumption and ensure linearity, a high-speed dynamic comparator is also used to implement a one-bit quantizer. The proposed architecture and the corresponding functionality are first simulated in MATLAB Simulink at the behavioral level. The results show that the designed modulator has an SNDR of 124.9 dB corresponding to an ENOB of 20.46 bits at a clock frequency of 256 kHz and 312.5 Hz input with a differential-mode voltage of 700 mV sinusoidal waveform. Based on SMIC 180 nm/1.8 V standard CMOS process on the Cadence platform, the subcircuit-level simulation is also performed, while the result shows that the proposed modulator can effectively achieve 115.52 dB SNDR, 18.90-bit ENOB, and 8.40 mW power consumption, which correspond to FoM W and FoM schreier of 0.067 pJ/step and 163.27 dB, respectively. The proposed modulator shows a significant advantage to be applied for high-precision analog-to-digital conversion applications such as high-quality equipment for audio, ECG and EEG signal sensing. [ABSTRACT FROM AUTHOR]

Electro-optic modulators (EOMs) are pivotal in bridging electrical and optical domains, essential for diverse applications including optical communication, microwave signal processing, sensing, and quantum technologies. However, achieving the trifecta of high-density integration, cost-effectiveness, and superior performance remains challenging within established integrated photonics platforms. Enter thin-film lithium niobate (LN), a recent standout with its inherent electro-optic (EO) efficiency, proven industrial performance, durability, and rapid fabrication advancements. This platform inherits material advantages from traditional bulk LN devices while offering a reduced footprint, wider bandwidths, and lower power requirements. Despite its recent introduction, commercial thin-film LN wafers already rival or surpass established alternatives like silicon and indium phosphide, benefitting from decades of research. In this review, we delve into the foundational principles and technical innovations driving state-of-the-art LN modulator demonstrations, exploring various methodologies, their strengths, and challenges. Furthermore, we outline pathways for further enhancing LN modulators and anticipate exciting prospects for larger-scale LN EO circuits beyond singular components. By elucidating the current landscape and future directions, we highlight the transformative potential of thin-film LN technology in advancing electro-optic modulation and integrated photonics. [ABSTRACT FROM AUTHOR]

Smart windows are crucial to dynamic control over light transmission to fulfill various demands in energy saving, privacy, and information display; however, most present technologies still perform a single function (often tint or haze adjustment) and require continuous electricity for operation. In this study, novel self‐assembled ionic liquid crystals (ILCs) doped with negative cholesteric liquid crystals (CLCs) to offer electrically switchable and stable scattering‐mode light modulators are presented. The novel smectic A phase based on the ILCs exhibits high solubility in the adopted nematics, enhancing the LC device's performance in several ways, including improved homogeneity, stable alignment quality, prolonged stability, and simplified fabrication. The LC device can potentially offer a dynamically rapid switching function between stable transparent (imperfect fingerprint textures) states and stable scattering (focal conic textures with small domains) states by using external stimuli and highly maintained multistable states for prolonged periods, even when the external stimuli are removed. The LC device also offers polarization‐independent scattering and transparent‐mode LC light modulators, low operating voltage, excellent contrast, and broad viewing angles. Its versatility and outstanding field‐off stability make it ideal for various applications such as smart lighting, building climate control, energy‐saving displays, and augmented reality (AR) glasses. [ABSTRACT FROM AUTHOR]

Holographic displays can generate light fields by dynamically modulating the wavefront of a coherent beam of light using a spatial light modulator, promising rich virtual and augmented reality applications. However, the limited spatial resolution of existing dynamic spatial light modulators imposes a tight bound on the diffraction angle. As a result, modern holographic displays possess low étendue, which is the product of the display area and the maximum solid angle of diffracted light. The low étendue forces a sacrifice of either the field-of-view (FOV) or the display size. In this work, we lift this limitation by presenting neural étendue expanders. This new breed of optical elements, which is learned from a natural image dataset, enables higher diffraction angles for ultra-wide FOV while maintaining both a compact form factor and the fidelity of displayed contents to human viewers. With neural étendue expanders, we experimentally achieve 64 × étendue expansion of natural images in full color, expanding the FOV by an order of magnitude horizontally and vertically, with high-fidelity reconstruction quality (measured in PSNR) over 29 dB on retinal-resolution images. All holographic displays and imaging techniques are fundamentally limited by the étendue supported by existing spatial light modulators. Here, the authors report on using artificial intelligence (AI) to learn an étendue expanding element that effectively increases étendue by two orders of magnitude. [ABSTRACT FROM AUTHOR]

This paper presents a high-speed V-band on-off keying (OOK) modulator in 65 nm CMOS based on distributed transmission lines architecture. The high-speed operation of the proposed OOK modulator is attained by distributing a single large switching transistor into smaller units. The effects of parasitic capacitances of each small switch are mitigated by series inductors, forming an artificial transmission line. The switch size and the number of stages are optimized for a reasonable balance between insertion loss and isolation. Small signal measurement of the OOK modulator reveals 3.8 dB insertion loss and 20.5 dB isolation at 60 GHz, with <5 dB insertion loss and >16 dB on-off ratio from 50 GHz to 70 GHz. Testing with a modulation setup shows the modulator is fully functional up to 5 Gbps at a 60 GHz carrier. Limitations of the test setup prevent modulation testing at >5 Gbps. The fabricated modulator does not consume any DC power and has an active footprint of 0.025 mm2. [ABSTRACT FROM AUTHOR]

A fully differential lumped linear driver for Mach–Zehnder modulator has been presented and assessed in 130‐nm SiGe BiCMOS technology. Multitopology peaking techniques, especially T‐coil peaking method, have been employed to flatten the frequency response and increase the bandwidth. Degeneration resistors have been used to enhance circuit linearity. Simultaneously, improvements have been made to the output stage of the conventional single emitter follower push–pull) circuit to enhance the output eye diagram quality at higher transmission rates. The fabricated driver achieved a differential gain of 16.2 dB with a bandwidth of over 50 GHz, corresponding to a fixed output swing of over 3.2 Vppd within the automatic gain control loop. Time domain measurements, limited in speed by the measurement setup, reported a data rate up to 56 Gb/s none return to zero and 40‐GBaud 4‐levels pulse amplitude modulation with a bit error rate less than 10−12. [ABSTRACT FROM AUTHOR]

In this paper, the security of linear optics cloning machine-enhanced passive state preparation continuous-variable quantum key distribution is investigated. The employment of passive state preparation eliminates the strict requirements on electro-optical modulators, while an appropriately tuned linear optics cloning machine can compensate the preparation noise introduced in passive state preparation and improve the system performance. The expression of the composable secret key rate in the finite-size regime of the proposed scheme is obtained. Simulation results demonstrate that the proposed scheme can effectively enhance the secret key rate and increase the maximum secure transmission distance. [ABSTRACT FROM AUTHOR]

Colorectal cancer (CRC) is the third most common cancer and the fourth leading cause of cancer-related death worldwide. The purpose of this study was to discover novel molecular pathways and potential prognosis biomarkers. To achieve this, we acquired five microarray datasets from the Gene Expression Omnibus (GEO) database. We identified differentially expressed genes between CRC and adjacent normal tissue samples and further validated them using The Cancer Genome Atlas (TCGA) database. Using various analytical approaches, including the construction of a competing endogenous RNA (ceRNA) network, Gene Ontology term and Kyoto Encyclopedia of Genes and Genomes pathway analyses, as well as survival analysis, we identified key genes and pathways associated with the diagnosis and prognosis of CRC. We obtained a total of 185 differentially expressed genes, comprising 17 lncRNAs, 30 miRNAs, and 138 mRNAs. The ceRNA network consisted of 17 lncRNAs, 25 miRNAs, and 7 mRNAs. Among the 7 mRNAs involved in the ceRNA network, SLC7A5 and KRT80 were found to be upregulated, while ADIPOQ, CCBE1, KCNB1, CADM2, and CHRDL1 were downregulated in CRC. Further analysis revealed that ADIPOQ and SLC7A5 are involved in the AMPK and mTOR signaling pathway, respectively. In addition, survival analysis demonstrated a statistically significant relationship between ADIPOQ, SLC7A5, and overall survival rates in CRC patients. In conclusion, our findings suggest that downregulation of ADIPOQ and upregulation of SLC7A5 in tumor cells lead to increased mTORC1 activity, reduced autophagy, enhanced angiogenesis, and ultimately contribute to cancer progression and decreased survival in CRC patients. [ABSTRACT FROM AUTHOR]

This paper presents a low-distortion and low-power multi-stage noise-shaping (MASH) architecture Sigma-Delta (Σ Δ) modulator with double-sampling. The modulator uses a cascade of integrator feed-forward (CIFF) structure as a cascaded modulator in a MASH architecture. Since the CIFF structure provides a feedforward path from the input signal to the quantizer, the input signal is directly transmitted to the output without loop processing, relaxing the linearity requirement of the modulator, reducing performance requirements for the OTA and harmonic distortion. Double-sampling technique is adopted in the first integrator to double the sampling rate, improving the accuracy of the modulator without the increase of power consumption. In order to eliminate the influence of capacitor mismatch in the sampling network, a fully floating differential switched capacitor (SC) feedback digital-to-analog (DAC) is used in the integrator. The simulation results show that the Σ Δ modulator achieves 113 dB signal-to-noise and distortion ratio (SNDR) and the power consumption is 3.15 mW from a 5 V power supply. [ABSTRACT FROM AUTHOR]

Existing video object segmentation (VOS) methods based on matching techniques commonly employ a reference set comprising historical segmented frames, referred to as 'memory frames', to facilitate the segmentation process. However, these methods suffer from the following limitations: (i) Inherent segmentation errors in memory frames can propagate and accumulate errors when utilized as templates for subsequent segmentation. (ii) The non-local matching technique employed in top-leading solutions often fails to incorporate positional information, potentially leading to incorrect matching. In this paper, we introduce the Modulated Memory Network (MMN) for VOS. Our MMN enhances matching-based VOS methods in the following ways: (i) Introducing an Importance Modulator, which adjusts memory frames using adaptive weight maps generated based on the segmentation confidence associated with each frame. (ii) Incorporating a Position Modulator that encodes spatial and temporal positional information for both memory frames and the current frame. The proposed modulator improves matching accuracy by embedding positional information. Meanwhile, the Importance Modulator mitigates error propagation and accumulation by incorporating confidence-based modulation. Through extensive experimentation, we demonstrate the effectiveness of our proposed MMN, which also achieves promising performance on VOS benchmarks. [ABSTRACT FROM AUTHOR]

The ongoing global research and development efforts on perovskite solar cells (PSCs) have led the power conversion efficiency to a high record of 26.1%. The optimization of PSC processing methods, the development of new compositions, and the introduction of passivation strategies are key factors behind the meteoric rise in performance. In particular, defect passivation and mitigation of ion migration via molecular engineering of the interfaces have played a critical role in enhancing the photovoltaic performance and operational stability of PSCs. The key interface engineering strategies enabling highly stable and efficient PSCs are focused here. The interface chemistry and the deleterious impact associated with it are discussed. The molecular design of effective modulators to mitigate the negative effects of perovskite interfaces is elaborated along with advanced characterization techniques to probe the interfaces. The progress of interface modification by multiple strategies is presented, and different modulator designs that are proven to be effective in mitigating the negative effects of perovskite interfaces are highlighted. Moreover, the main properties of effective interface modification strategies are summarized, and general design principles are deduced for future applications. Here, important insights are provided into the fields of material chemistry, physical chemistry, and optoelectronics. [ABSTRACT FROM AUTHOR]

The huge development of micro-/nano-manufacturing techniques on different materials has greatly expanded the possibilities of realizing on-chip multifunctional devices on photonic integrated circuits. In recent years, we have witnessed technological advancements, such as active photonic applications through hybrid integration. In this Perspective, we first summarize the integrated photonic materials, hybrid integration technologies, and corresponding coupling techniques in hybrid integration and give the technique prospects. We also introduce significant advances in hybrid integration technologies for active photonic applications, such as laser sources, optical frequency combs, and modulators, and give our views that are likely to develop rapidly. Finally, we discuss the challenges in hybrid technologies and photonic applications. [ABSTRACT FROM AUTHOR]

Terahertz amplitude and phase modulation technologies are crucial for terahertz communication, radar, and imaging. However, most current approaches can only achieve either amplitude or phase modulation. In this paper, we present a low terahertz frequency on-chip multi-functional modulator that consists of a hybrid coupler and reflection meta-structure. High-performance amplitude modulation is achieved by combining series resonant absorption of series coupling branch with resonance enhancement of parallel coupling branch in the reflection meta-structure. Meanwhile, the enhanced resonance provides a larger range of phase shifts, enabling effective amplitude and phase modulation in two different frequency regions. Therefore, we realize an amplitude modulation in the range of 115–135 GHz with a minimum transmission loss of 4 dB and a modulation depth of over 10 dB. At the same time, we achieved a continuous phase shift in the 103–113 GHz region, as well as a 180° two-bit phase shift in the 107–109 GHz range with only 5.7 dB transmission loss. Our simple method for terahertz amplitude and phase multi-functional modulation offers the potential to construe terahertz multifunctional integrated systems. [ABSTRACT FROM AUTHOR]

The tropical western Pacific is recognized as an important region for stratosphere–troposphere exchange but lies in a data-sparse location that had a measurement gap in the global ozone sounding network. The Palau Atmospheric Observatory (PAO, approx. 7.3 ∘ N, 134.5 ∘ E) was established to study the atmospheric composition above the remote tropical western Pacific with a comprehensive instrumental setup. Since 2016, two laboratory containers in Palau host a Fourier transform infrared spectrometer; a lidar (micro-lidar until 2016, cloud and aerosol lidar from 2018); a Pandora 2S photometer; and laboratory space for weather balloon soundings with ozone, water vapor, aerosol, and radiosondes. In this analysis, we focus on the continuous, fortnightly ozone sounding program with electrochemical concentration cell (ECC) ozonesondes. The aim of this study is to introduce the PAO and its research potential, present the first observation of the typical seasonal cycle of tropospheric ozone in the tropical western Pacific based on a multiannual record of in situ observations, and investigate major drivers of variability and seasonal variation from January 2016 until December 2021​​​​​​​ related to the large-scale atmospheric circulation. We present the PAO ozone (O3) volume mixing ratios (VMR) and relative humidity (RH) time series complemented by other observations. The site is exposed to year-round high convective activity reflected in dominating low O3 VMR and high RH. In 2016, the impact of the strong El Niño is evident as a particularly dry, ozone-rich episode. The main modulator of annual tropospheric O3 variability is identified as the movement of the Intertropical Convergence Zone (ITCZ), with the lowest O3 VMR in the free troposphere during the ITCZ position north of Palau. An analysis of the relation of O3 and RH for the PAO and selected sites from the Southern Hemispheric Additional Ozonesondes (SHADOZ) network reveals three different regimes. Palau's O3 / RH distribution resembles the one in Fiji, Java and American Samoa but is unique in its seasonality and its comparably narrow Gaussian distribution around low O3 VMR and the evenly distributed RH. A previously found bimodal distribution of O3 VMR and RH could not be seen for the full Palau record but only during specific seasons and years. Due to its unique remote location, Palau is an ideal atmospheric background site to detect changes in air dynamics imprinted on the chemical composition of the tropospheric column. The efforts to establish, run and maintain the PAO have succeeded to fill an observational gap in the remote tropical western Pacific and give good prospects for ongoing operations. The ECC sonde record will be integrated into the SHADOZ database in the near future. [ABSTRACT FROM AUTHOR]

Herein, a new type of infrared film using single‐walled carbon nanotubes (SWNTs) is developed. The optimal sonication settings to produce SWNTs with the highest possible absorption of infrared light are discovered. A hybrid infrared modulator that combines SWNTs with ionic liquids, with a very fast response time is also developed. By carefully controlling the size of the SWNT bundles and the pore size of the filter membrane used to deposit the SWNTs, a response time of a few hundred microseconds (635 μs) at the half‐power point is achieved, which is the optical 3‐dB point. This technology has the potential to be used in a variety of innovative applications, such as smart windows and military camouflage, due to its excellent infrared optical properties. [ABSTRACT FROM AUTHOR]

Humans can generate and sustain a wide range of walking velocities while optimizing their energy efficiency. Understanding the intricate mechanisms governing human walking will contribute to the engineering applications such as energy-efficient biped robots and walking assistive devices. Reflex-based control mechanisms, which generate motor patterns in response to sensory feedback, have shown promise in generating human-like walking in musculoskeletal models. However, the precise regulation of velocity remains a major challenge. This limitation makes it difficult to identify the essential reflex circuits for energy-efficient walking. To explore the reflex control mechanism and gain a better understanding of its energy-efficient maintenance mechanism, we extend the reflex-based control system to enable controlled walking velocities based on target speeds. We developed a novel performance-weighted least squares (PWLS) method to design a parameter modulator that optimizes walking efficiency while maintaining target velocity for the reflex-based bipedal system. We have successfully generated walking gaits from 0.7 to 1.6 m/s in a two-dimensional musculoskeletal model based on an input target velocity in the simulation environment. Our detailed analysis of the parameter modulator in a reflex-based system revealed two key reflex circuits that have a significant impact on energy efficiency. Furthermore, this finding was confirmed to be not influenced by setting parameters, i.e., leg length, sensory time delay, and weight coefficients in the objective cost function. These findings provide a powerful tool for exploring the neural bases of locomotion control while shedding light on the intricate mechanisms underlying human walking and hold significant potential for practical engineering applications. Author summary: Previous reflex-based control systems face significant limitations in accurately regulating walking velocity owing to the vast number of control parameters involved. This hinders identifying essential reflex circuits that have a significant impact on energy-efficient walking across a wide range of speeds. Our research tackles this challenge by developing a reflex-based control framework that precisely regulates the velocities of the bipedal model through the performance-weighted least squares (PWLS) method that optimizes the control parameter values while considering energy efficiency. Through a detailed analysis, we identify two key reflex circuits essential for generating energy-efficient walking over a wide range of velocities. We hope that our research will inspire future investigations into reflex mechanisms and facilitate the development of advanced walking control systems for practical applications, such as gait-assisted exoskeletons and prosthetic legs, and robot control. [ABSTRACT FROM AUTHOR]

While Pt‐based binary alloys hold promising potential as cathode catalysts in proton exchange membrane fuel cells (PEMFCs) due to their desirable properties compared with monometallic counterparts, their weak interactions with carbon support make them challenging for practical cell implementation. Here, the PtFe alloys are uniformly deposited onto the surface of Fe‐Nx‐enriched nanocubes (FeNC) via surface confinement and internal vapor phase etching. The combined action of PtFe alloy and FeNC support acts as the electronic structure modulator resulting in the optimized intermediate adsorption (revealed by density function theory calculations), thereby boosting intrinsic activity to oxygen reduction reaction (ORR) and simultaneously enhancing their interactions. The resultant Pt1Fe1 @ Fe0.5NC‐900 catalyst with a low Pt loading (0.065 mgPt cm−2) exhibits excellent mass activity and stability toward ORR in acidic media. When incorporated into a PEMFC, it delivers a superior peak power density of 1.05 W cm−2 and satisfactory stability performance. [ABSTRACT FROM AUTHOR]

The existing frequency bands, such as the C-band and L-band, are becoming increasingly crowded and cannot meet the growing demand for high-speed data rate services. To overcome spectrum congestion, meet future business needs, and overcome the bottlenecks of traditional electronic methods, we have modified an approach for generating W-band mm-wave signals with octupling frequency without the need for an optical filter. One integrated modulator consisting of two push-pull Mach-Zehnder modulators (MZM) in series is employed to achieve W-band signal generation. The octupling frequency signal generation depends on ±4th optical sidebands to beat frequency in the photodetector. For capturing ±4th optical sidebands, the bias point of the two push-pull MZMs needs work at the peak point, and the modulation index of the two MZMs should be simultaneously set to 2.4. We have conducted detailed mathematical derivation and computer simulation for the scheme, demonstrating its correctness. The results show that the optical sideband suppression ratio is not less than 45.73 dB, and the RF sideband suppression ratio can reach 37.64 dB. [ABSTRACT FROM AUTHOR]

Instability is a design challenge with high-order delta-sigma modulator (DSM). DSM stability shows maximum stable amplitude (MSA) where it achieves adequate precision across the bandwidth. Increasing DSM order reduces the stable amplitude range. In addition, the design of an efficient noise transfer function (NTF) is necessary for the synthesis of a DSM. In this brief, a systematic method to design stable high-order DSM without the need for a stability-recovery mechanism is presented. The proposed design method can be used for high-order single-bit and multi-bit DSM with maximum stability. To achieve maximum DSM amplitude stability, systematic simulation is used to design coefficients and obtain SNR values at different points of bandwidth. Actual SNR values will ensure that the genetic algorithm will search and find optimum stability coefficients, the most important feature of the proposed method. The design method is implemented for two DSMs with different specifications and the results are compared with similar studies, showing that the proposed method has acceptable performance. [ABSTRACT FROM AUTHOR]

Signal remodulation mechanism is a promising cost-effective choice for future optical access networks. This paper investigates the scheme of the phase modulator to remodulate upstream data in the bidirectional WDM PON and TWDM PON system. The simulation results of downstream is carried out using two data formats such as RZ and NRZ at varying lengths of single mode fibers in this scheme. In addition, the upstream transmission compares different remodulators such as Phase modulator, Mach–Zehnder modulator (MZM) and Electroabsorption modulator. By analyzing the eye diagram and Q-value, the performance of upstream and downstream transmission is obtained. It is observed that the PM remodulation TWDM-PON with NRZ modulation format has better performance, which is a rational solution for NG-PON2 cost-effectiveness. [ABSTRACT FROM AUTHOR]

Different types of laser source modulation techniques have been used in various applications depending on the objective. As optical systems extract the laws and the best solutions from experiments and simulations, the present study uses simulation software with different modulation types so the output signals can be compared. The modulators used are Mach-Zehnder, which is an external modulator, and electro-absorption modulator and laser rate equation modulator, which are direct modulators. All these types have an optical link multimode (MM) fiber with a photodiode in the receiver end that can be modeled. The input and output signals are analyzed using different types of modulations. [ABSTRACT FROM AUTHOR]

Click chemistry reactions constitute an important and relatively new approach in the medicinal chemistry toolbox and offer substantial advantages to medicinal chemists in terms of overcoming the limitations of facile chemical synthesis, increased throughput, yields and improved quality of compound libraries. Over the last two decades, click chemistry has been widely used in different aspects of carbonic anhydrase (CA, EC 4.2.1.1) modulators drug design. This review provides an overview of the general principles and applications of click chemistry in CA-related research, including the design of selective CA inhibitors (CAIs), their applications against several diseases such as innovative anticancer and anti-infective agents, fluorescent and radiopharmaceutical probes as new theranostic agents, as well as their application in protein labelling. [ABSTRACT FROM AUTHOR]

This paper presents a high resolution delta-sigma modulator for continuous acquisition of electroencephalography (EEG) signals. The third-order single-loop architecture with a 1-bit quantizer is adopted to achieve 22.3-bit resolution. The effects of thermal noise on the performance of the delta-sigma modulator are analyzed to reasonably allocate the switched-capacitor sizes for optimal signal to noise ratio (SNR) and minimum chip area. The coefficients in feedback path and input path are optimized to avoid the signal distortion under the full-scale input voltage range with almost no increase in total capacitance sizes. Fabricated in 0.5 µm CMOS technology and powered by a 5 V voltage supply, the proposed delta-sigma modulator can achieve 136 dB peak SNR with 16 Hz input and 137 dB dynamic range in 100 Hz signal bandwidth with an oversampling ratio of 512. The modulator dissipates 700 µA. The core chip area is 1.96 mm 2 . The modulator occupies 1.41 mm 2 and the decimator occupies 0.55 mm 2 . [ABSTRACT FROM AUTHOR]

To date, zone-plate-array lithography has employed an array of binary pi-phase zone plates, each 135 μm in diameter, operating at 405 nm wavelength, in conjunction with a spatial-light modulator and a moving stage, to expose large-area patterns in photoresist without a mask. Although the low focal efficiency (<34%) and high background (>66%) of such zone plates can be mitigated via proximity-effect correction, increased focal efficiency would enable higher quality patterning. To that end, we have designed flat, diffractive-optical "metalenses." Each is first divided into Fresnel zones, across which the effective index-of-refraction is modulated by forming appropriate pillars or holes such that diffracted beams interfere constructively at the focal spot, located 100 μm in front of the lens plane. The diffraction efficiency of each zone is simulated using rigorous-coupled-wave analysis. A genetic algorithm is then used to determine if higher efficiency can be achieved by repositioning of the pillars or modifying their widths. MEEP software is used to predict focal efficiency of the completed metalens design. Scanning-electron-beam lithography was used to fabricate effective-index-modulated metalenses in CSAR-62 e-beam resist. In some cases, the focal properties and efficiencies of such structures were measured, yielding focal efficiencies up to 54%. In other cases, the e-beam-written pattern was transferred into a spin-on hard mask and then into an organic dielectric of 1.9 index of refraction using reactive ion etching. Focal efficiencies up to 69% are predicted for such structures, a significant improvement over the binary pi-phase zone plates used previously. [ABSTRACT FROM AUTHOR]

This paper presents a low-ripple and high-efficiency buck–boost DC–DC converter with delta-sigma modulator controller that converts 1.8 V to 1.2 V and 3.3 V. A current and voltage closed-loop controller has been designed to achieve better performance simultaneously such as lower settling-time, steady-state error and over shoot and under shoot. The converter is started in the current controller mode initially, when the output voltage approaches the desired value, the power stage is controlled with the voltage controller mode. PI compensator and a third-order delta-sigma modulator are utilized in the voltage mode. Also, the closed-loop stability of the designed converter has been analyzed with Lyapunov method using converter nonlinear model. This work has been simulated in MATLAB-SIMULINK environment. The performance results show that the maximum efficiency of the closed-loop DC–DC converter is 90% at 5 MHz switching frequency, and the output voltage ripple is 0.5% and 0.6% for the buck and boost modes, respectively. Also, the simulation results demonstrate the closed-loop stability of the converter in the presence of 10% load variation. [ABSTRACT FROM AUTHOR]

The article presents the solution of a power rectifier system dedicated to cooperating with an electric generator based on a special synchronous generator, which can be used in wind or water energy systems. In this generator, a pair of three-phase windings in a stator is utilized. One of the windings is connected in a star, and the second one is connected in a delta configuration. Two six-pulse uncontrolled (diode) rectifiers are included at the outputs of the windings. The rectifiers are coupled by a pulse transformer. The primary windings of this transformer are supplied by a power-electronics current source called a current modulator. With the help of this current modulator, the quasi-sinusoidal magnetomotive force (mmf) in the stator of the machine can be obtained. Additionally, to improve the efficiency of the described system, the low-power transistor rectifier, which is connected to the DC bus of the current modulator, has been used. With the help of this converter, it is possible to control and stabilize the voltage level in a DC circuit. It works, in this case, in inverter mode. The principle of working and elaborated control methods of the current modulator and the additional rectifier are presented. Selected results of simulation and experimental tests are also presented. [ABSTRACT FROM AUTHOR]

A great number of switching power supplies are used to provide a variable voltage for resistive‐inductive loads. However, some applications in industry, require a regulated current with a constant voltage such as battery charging systems, LED drivers, and laboratory equipment for power converters connected to PV cells. Additionally, some constant voltage systems are intrinsically unstable, and therefore, they cannot be used without a closed‐loop compensatory circuit. Hence, this article describes a novel smooth starter system behaving as a current source for constant voltage applications. The proposed technology is implemented by a quadratic buck converter, and then, a self‐oscillating control technique is applied for performing the output current regulation of the converter, which is capable of aiding to improve the system performance, stabilize the overall system, protect the converter from transient current oscillations, and provide an acceptable control performance. In addition to practical aspects, soft starter methods and limitation of the constant voltage power converter are mentioned and described in this article. The designed structure has not only the advantages of smooth response and simplicity to construct but also performs a nearly zero steady‐state error regulation. The power stage, the control scheme, and the modulator are explained in detail and validated by experiments. [ABSTRACT FROM AUTHOR]

Bridge sensors are widely used in military and civilian fields, and their demand gradually increases each year. Digital sensors are widely used in the military and civilian fields. High-precision and low-power analog-to-digital converters (ADCs) as sensor read-out circuits are a research hotspot. Sigma-delta ADC circuits based on switched-capacitor topology have the advantages of high signal-to-noise ratio (SNR), good linearity, and better compatibility with CMOS processes. In this work, a fourth-order feed-forward sigma-delta modulator and a digital decimation filter are designed and implemented with a correlated double sampling technique (CDS) to suppress pre-integrator low-frequency noise. This work used an active pre-compensator circuit for deep phase compensation to improve the system's stability in the sigma-delta modulator. The modulator's local feedback factor is designed to be adjustable off-chip to eliminate the effect of process errors. A three-stage cascade structure was chosen for the post-stage digital filter, significantly reducing the number of operations and the required memory cells in the digital circuit. Finally, the layout design and engineering circuit were fabricated by a standard 0.35 μm CMOS process from Shanghai Hua Hong with a chip area of 9 mm2. At a 5 V voltage supply and sampling frequency of 6.144 MHz, the modulator power consumption is 13 mW, the maximum input signal amplitude is −3 dBFs, the 1 Hz dynamic range is about 118 dB, the modulator signal-to-noise ratio can reach 110.5 dB when the signal bandwidth is 24 kHz, the practical bit is about 18.05 bits, and the harmonic distortion is about −113 dB, which meets the design requirements. The output bit stream is 24 bits. [ABSTRACT FROM AUTHOR]

Quantum key distribution (QKD) research has yielded highly fruitful results and is currently undergoing an industrialization transformation. In QKD systems, electro-optic modulators are typically employed to prepare the required quantum states. While various QKD systems operating at GHz repetition frequency have demonstrated exceptional performance, they predominantly rely on instruments or printed circuit boards to fulfill the driving circuit function of the electro-optic modulator. Consequently, these systems tend to be complex with low integration levels. To address this challenge, we have introduced a modulator driver integrated circuit in 0.18 µm SiGe BiCMOS technology. The circuit can generate multiple-level driving signals with a clock frequency of 1.25 GHz and a rising edge of ∼50 ps. Each voltage amplitude can be independently adjusted, ensuring the precise preparation of quantum states. The measured signal-to-noise ratio was more than 17 dB, resulting in a low quantum bit error rate of 0.24% in our polarization-encoding system. This work will contribute to the advancement of QKD system integration and promote the industrialization process in this field. [ABSTRACT FROM AUTHOR]

This research aims to introduce an innovative method of constellation modification in MPSK data transmission through utilization of frequency multiplication. This method presents a significant solution for providing efficient data transmission in millimeter wave frequency band, addressing the requisites for high data rates and capacity. However, the application of frequency multiplication to MPSK signal causes problems wherein data recovery becomes unattainable due to nonlinearity. Hence, a modified MPSK modulator is developed. Along with the standard MPSK modulator, back-to-back and line-of-sight (LOS) measurements of the modified MPSK modulator are performed. To conduct the standard and modified MPSK modulators in real-time, the development of transmitter and receiver blocks is undertaken using LabVIEW and experimentation is performed employing the SDRs. Comparative analysis reveals that the modified MPSK modulator, conceived through the proposed method, yields improvement in error performance while mitigating the computational burden from digital processing. Importantly, these enhancements are achieved without necessitating alterations in receiver. BER results for measurements of standard and modified MPSK are obtained. The findings substantiate the effectiveness of the proposed method, manifesting a discernible enhancement in error performance. This method proves appropriate for MPSK data in experimental millimeter wave band investigations utilizing frequency multiplier chains. [ABSTRACT FROM AUTHOR]

The last decade has witnessed an increasing interest in metamaterial absorbers (MMAs) because of their huge potential in a wide range of applications including energy harvesting, photodetectors, sensors, light modulators, infrared camouflage and wireless communication. Recently, machine learning (ML) has become one of the modern and powerful tools that can examine the design data in order to forecast the absorption behavior with much less effort and cost-effectiveness than conventional experimental and computation approaches. In this work, we utilize two ML algorithms, Polynomial Regression (PR) and Random Forest Regression (RFR), to predict the absorption strength and frequency of a symmetric disk-shape metamaterial structure operating within 10 and 16 GHz. The proposed models are trained on hundreds of simulation-generated samples. We show that fine-tuning some hyperparameters results in higher forecasting performance. The dependence of predicted results on input parameters demonstrates that PR has better performance in predicting absorption strength, while both algorithms share similar accuracy in predicting the absorption frequency. [ABSTRACT FROM AUTHOR]

Finite control set model predictive control (FCS–MPC) has been deployed extensively in electric motor drives and power electronics applications. Many advantages, including fast transient response, have been reported. However, the improvement of its steady‐state performance, that is, suppression of current ripple, is one of the main problems of a conventional FCS–MPC strategy. This article presents a current control strategy based on FCS–MPC using the concept of variable voltage smoothing. In the proposed method, a finite set of novel voltage vectors, produced by the smoothing process, are introduced as candidate control input candidates, and the controller generates the optimum output voltage using a modulator integrated with the FCS–MPC scheme. Thus, the voltage candidates are generated flexibly, and a suitable voltage for acceptable steady‐state performance is determined as the control input. In addition, the smoothness in the proposed concept can be updated automatically depending on the drive situation, that is, transient, or steady‐state operation, thus avoiding degradation of dynamic performance. Simulation and experimental results obtained with a permanent magnet synchronous motor drive system demonstrate that the proposed control strategy is effective to achieve current control with fast tracking performance while suppressing current ripple. [ABSTRACT FROM AUTHOR]