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Positron emission tomography (PET) is a functional imaging technique introduced in 1970s. Over the years, PET was used alone but is in 2000 when the first hybrid PET/CT device was clinically introduced. Since then, PET has continuously been marked by technological developments, being the most recent one the introduction of silicon photomultipliers (SiPMs) as an alternative to standard photomultiplier tubes used in analog PET/CT systems. SiPMs, the basis for the so called digital PET/CT systems, are smaller than standard photomultiplier tubes (enabling higher spatial resolution) and provide up to 100% coverage of the crystal area, as well as high sensitivity, low noise, and fast timing resolution. SiPMs in combination with optimized acquisition and reconstruction parameters improve the localization of the annihilation events, provide high definition PET images, and offer higher sensitivity and higher diagnostic performance. This article summarizes the evidence about the superior performance of the state of the art digital PET and highlights its potential clinical implications. Digital PET opens new perspectives in the quantification and characterization of small lesions, which are mostly undetectable using analog PET systems, potentially changing patient management and improving outcomes in oncological and non-oncological diseases. Moreover, digital PET offers the possibility to reduce radiation dose and scan times which may facilitate the implementation of PET to address unmet clinical needs.

In this paper, we present the first CMOS SPAD with performance comparable or better than that of the best custom SPADs, to date. The SPAD-based design, fully integrated in 180 nm CMOS technology, achieves a peak PDP of 55% at 480nm with a very broad spectrum spanning from NUV to NIF and a normalized DCR of 0.2cps/m2, both at 6V of excess bias. Thanks to a dedicated CMOS pixel circuit front-end, an afterpulsing probability of about 0.1% at a dead time of3ns were achieved. We designed three SPADs with a diameter of 25, 50, and 100m to study the impact of size on the timing jitter and to create a scaling law for SPADs. For these SPADs, a SPTR of 12.1ps, 16ps, and 27ps was achieved at 6V of excess bias, respectively. The SPADs operate in a wide range of temperatures, from -65C to 40C, reaching a normalized DCR of 1.6 mcps/m2 at 6V of excess bias. The proposed SPADs are ideal for a wide range of applications, including LiDAR, super-resolution microscopy, QRNGs, QKD, fluorescence lifetime imaging, time-resolved Raman spectroscopy, to name a few.

This paper reviews materials and structural approaches that have been developed to reduce the excess noise in avalanche photodiodes and increase the gain-bandwidth product.

The following paper is devoted to an amplifier with gain control (Variable Gain Amplifier). The role of amplification and gain control is addressed separately from the very beginning, to achieve the greatest possible independence of the required parameters both for the amplifier itself (gain size, bandwidth, noise figure) and for the gain controller (energy consumption control, distortion). This feature is very convenient and is not common with other VGA amplifiers. The core of the amplifier consists of an operational amplifier with voltage feedback (VFB) in an inverting circuit, to the feedback of which a gain regulator executed with a diode bridge is connected in parallel. The analysis of the simplified circuit model shows that it is possible to obtain a variable-gain amplifier that maintains its bandwidth. The control of the gain is continuous and only one element, the variable resistance, is sufficient for its control. Continuous control with one element preserving the bandwidth of an operational amplifier with VFB is unique and the authors are unaware of any other similar solution. The proposed VGA amplifier also excels in low noise and negligible distortion. If maximum gain is required, the diode bridge is disconnected and does not contribute to the resulting noise of the VGA amplifier. Because the diode bridge is connected between the output of the operational amplifier and its inverting input, and because the inverting input is current controlled, the diode bridge processes only a portion of the output voltage of the amplifier, thus preventing more noticeable distortion. The distortion is further suppressed due to the simultaneous action of four diodes in the bridge, whose characteristics are reciprocal for the signal path. The presented construction is relatively simple and can be a topic not only for other microelectronic structures, but also for applications from discrete components. The achieved parameters of the presented connection are as follows: gain change 0 to 20 dB, constant bandwidth 7 MHz, distance III. harmonics min. 30 dB at an output voltage of 0.5 V, maximum power spectral density at the output 25 $\cdot 10^{-15}\,\,\text{V}^{2}$ Hz−1.

In this paper a transimpedance amplifier is presented, which features a bandwidth of 97 GHz, 66 dBΩ maximum transimpedance gain, and 6.3 pA/√Hz integrated noise current density, operating at up to 120 Gb/s and consuming only 145mW. Reaching a higher bandwidth at a noise performance comparable to the state-of-the-art, is the novelty of this work. It was achieved by combining a low-bandwidth input stage, reducing the total noise, and a multi-stage post equalization. The gain peaking technique through cascading emitter follower stages is employed in a broadband transimpedance amplifier as a post equalizer. To the best of the author’s knowledge, the presented design shows the best performance in terms of overall gain, bandwidth, and noise for the lowest power consumption compared to state-of-the-art designs.

Covert communication is critical to guarantee a strong security and secure user privacy. In this work, we consider adversary’s noise and channel uncertainties and analyze their impact on adversary’s optimum detection performance and the throughput of covert messages. We determine the throughput of covert messages and its gain and loss by having adversary’s channel uncertainty and fading channel, respectively. The results show that fading is essential to hide information, particularly for low noise uncertainty or at high SNR. The improvement of adversary’s optimum detection performance, hence the covert throughput, under channel uncertainty is more significant for larger noise uncertainty. The covert throughput is gained by having channel uncertainty roughly 12–19% when the noise uncertainty is about 1–2 dB.

This work introduces a new low‐noise current‐reused CMOS active inductor (AI) based on Gyrator‐C configuration. In the proposed AI, a simple common‐source amplifier is utilised for boosting effective Gm and improving noise performance of the AI. While the Gm‐boosting technique improves the noise performance as well as the quality factor of the inductor, a resistor is also added to the feedback path for more quality factor improvement. Rigorous analysis of the proposed circuit shows a significant noise performance and quality factor enhancement. In order to verify the concept and confirm the mathematical analysis, the AI is designed and simulated in a commercial 0.18 μm RF‐CMOS technology. The simulation results show that the proposed inductor operates in 1 to 7.2 GHz frequency range, has a 9 nH inductance at 2.864 GHz frequency and 650 μW total power dissipation at 1.8‐V supply voltage. Maximum quality factor of 90 is achieved at 2.864 GHz frequency and a quality factor greater than 40 is obtained from 2.4 to 3.3 GHz. The input‐referred current noise of the proposed inductor is as low as 22 pA/√Hz showing 30.5% improvement compared to the conventional AI. The proposed AI is also tunable and sweeping the tuning voltage results in changing extracted inductance from 4.35 to 15.2 nH with only a chip area of 0.003 mm2. Post‐layout and different Monte Carlo simulation results also confirm the robust operation of the proposed AI against different process non‐idealities.

Wireless communication is a constantly evolving and forging domain. The action of the RF input module is critical in the radio frequency signal communication link. This paper discusses the design of a RF high frequency transistor amplifier for unlicensed 60 GHz applications. The Transistor used for analysis is a FET amplifier, operated at 60GHz with 10 mA at 6.0 V. The simulation of the amplifier is made with the Open Source Scilab 6.0.1 console software. The MESFET is biased such that Sll = 0.9

This brief presents a 4th-order continuous-time analog filter based on Flipped-Source-Follower stage. Source-Follower (SF) filters typically adopt pseudo-differential topology (critical for matching and bulk/substrate noise rejection) and are realized in not recent CMOS processes (130nm or 180nm) due to the intrinsic voltage headroom required by SF operation. The proposed device solves the above limitations by proposing a fully-differential circuital topology, which improves by 13 dB the power supply rejection with respect to pseudo differential approach, and by operating in 28nm-CMOS process, thanks to a proper level-shifter transistor, which enables optimum biasing point and enhances filter dynamic range. The prototype is composed by the cascade of two biquadratic cells. It features 90 MHz −3 dB bandwidth, and consumes 816 $\mu \text{W}$ power (408 $\mu \text{W}$ per cell) from a 1V supply. Dynamic-Range is 64 dB with 140 $\mu \text{V}_{\mathrm{ RMS}}$ output noise, and at 0.32 V0-PEAK differential output voltage swing. Figure-of-Merit is 156 dBJ $^{-1}$ .

The inability to exhaust airborne formaldehyde and other volatile organic compounds from a gross anatomy laboratory is an impediment to gross anatomical education. Despite the importance of removing harmful airborne chemicals, there is scant information regarding how to build effective local exhaust ventilation systems. In this study, various exhaust systems were built and assessed for exhaust flow, airborne formaldehyde removal, and noise production with the aim of identifying inexpensive and simple exhaust systems that can create a healthy and quiet exhaust flow from a downdraft dissection table. The results of the study include details regarding 11 local exhaust ventilation systems, including an exhaust system that produces an exhaust flow of 777cfm, allows no detectable airborne formaldehyde (0ppm) despite a 1000mL pool of formalin (composed of 37% formaldehyde) positioned directly beneath a formaldehyde-meter, and operates at a very low noise level (maximum of 69.2dBA with coexisting baseline room noise of 38.6dBA). Furthermore, the aforementioned local exhaust ventilation system costs less than $400 (USD) to build and can be assembled in a matter of minutes with minimal know-how. The local ventilation systems assessed in this study were capable of down-drafting air away from the breathing zone; therefore, the utilization of such local ventilation systems may have the additional benefit of decreasing the person-to-person transmission of aerosolized pathogens. This information marks an improvement in laboratory health and safety measures, facilitates the creation of gross anatomy laboratories, and improves access to gross anatomical education.

The observed data of transient electromagnetic (TEM) systems is often contaminated by various noises. Even after stacking averages or applying various denoising algorithms, the interference of the system noise floor cannot be eliminated fundamentally, which limits the survey capability and detection efficiency of TEM. To improve the noise performance of the TEM receiver, we have designed a low-noise amplifier using the current source long-tail differential structure and JFET IF3602 through analyzing the power spectrum characteristics of the TEM forward response. By the designed circuit structure, the JFET operating point is easy to set up. The adverse effect on the JFET differential structure by JFET performance differences is also weakened. After establishing the noise model and optimizing the parameters, the designed low-noise differential amplifier has a noise level of 0.60nV/Hz, which increases the number of effective data 2.6 times compared with the LT1028 amplifier.

Purpose This study aims to present two stage pseudomorphic high electron mobility transistor-based low noise amplifier (LNA) designed using low temperature co-fire ceramic (LTCC) technique for ultra-high frequency (UHF) band. The LNA operates in the frequency range of (400∼500) MHz which is suitable for wireless communication applications. Design/methodology/approach This LNA uses resistive capacitive (RC) feedback in the first stage to have wide bandwidth and interstage network for gain enhancement. By using external RC feedback, stability is improved and noise matching in the input stage is isolated by decoupling inductor. The excellent performance parameters including gain, noise figure (NF), wideband and linearity are attained without affecting the power consumption, compactness and cost of the proposed design. Findings Simulation is carried out using advanced design software and the result shows that gain of 33.7 dB, NF 0.416 dB and 1 dB compression point (P1dB) of 18.59 dBm are achieved with a supply voltage of 2.5 V. The return loss of input and output are −19.3 dB and −10.5 dB, respectively. From the above aforementioned parameters, it is confirmed that the proposed LNA is a promising candidate for receivers where high gain and very low NF are always demandable with good linearity for applications operating in the UHF band. Originality/value The innovation of the proposed LNA is that the concurrent attainment of high gain, low NF, wideband, optimum input matching, good stability by RC feedback and interstage network using LTCC technique to achieve robustness, low cost and compactness to prove the applicability of design for wireless applications.

A multidisciplinary optimization design to simultaneously enhance the aeroacoustic and aerodynamic performance of an cooling fan is performed. The flow analysis of the cooling fan is conducted by solving three dimensional steady-state RANS equations with shear-stress transport turbulence model. Based on the results of the steady flow, aeroacoustic analysis is performed by using the Hanson and Brooks model. A multi-objective optimization is performed to simultaneously improve the efficiency and reduce the sound pressure level through an improved non-dominated sorting gentic algorithm. A Kriging surrogate model is used to approximate the function value while reducing computational cost. Series of optimum designs on the pareto front yielded increases in efficiency and decreases in the sound pressure level compared to the reference design. Through numerical analysis and experimental test, the aerodynamic efficiency is increased by 5% and the total sound pressure level is reduced by 4dB without loss of air volume for the selected optimized cooling fan. The thining of rotor boundary layer and inward load shift are the main factors to improve aerodynamic efficiency and reduce noise of the cooling fan.

In Korea, road noise is assessed as a measurement method of exterior noise emitted by road vehicle for management standards by the National Institute of Environmental Sciences. In this method, the noise felt at the actual pickup point is measured as LAeq (the roadside equivalent noise level). Recently, to clarify the standard for measuring noise on low-noise pavements, the CPX (ISO11819-2; Close-proximity method) was first introduced in the Porous Pavement Guidelines of the Ministry of Land, Infrastructure and Transport. According to ISO, the CPX adopts the side microphone as a mandatory measurement location, and the rear optional. The side location has been a mandatory due to its high correlation with SPB (ISO 11819-1, Statistical Pass-by method). However, according to our previous study on the correlation evaluation between L and CPX rear microphone noise level, both noise reduction effect was about 9-12 dB(A) showed a high correlation in Korea where heavy road traffic is common. The following study aims to show the consistent correlation between the L and CPX rear noise level. Furthermore, it is intended to be helpful in selecting the location of the CPX microphone that can most effectively represent the actual noise on the low-noise pavement in Korea.

Urban aerial mobility (UAM) is a promising approach to improve the traffic situation in gigantic cities, which, however, may encounter significant noise pollution issues. An integrated research platform, which is being established at HKUST, to include noise generation, long-distance propagation, and perception at the observers is timely to assess the environmental impact of UAM noise and to develop low-noise designs and flight planning. A high-quality test rig in the anechoic aerodynamic facility at HKUST is employed to measure the propeller aeroacoustics and aerodynamics, and to enable the innovative noise control device and design studies. The measurements and high-fidelity simulations using an in-house computational aeroacoustics solver can lead to comprehensive databases to facilitate and validate the development of physics-oriented noise prediction models. Also, high-efficient implementation of the boundary element method is conducted to account for the noise scattering due to the fuselage and then to evaluate the impact of UAM layout on the directivity patterns, which will then be efficiently projected to the far-field observers using the advanced Gaussian beam tracing with the effects due to moving source, atmospheric attenuation, and refraction, complex boundary absorption and reflection incorporated. Low-noise flight planning is then be made accordingly.

Due to the increasing bypass ratios of modern engines, the fan stage is increasingly becoming the dominant source of engine noise. Accordingly, it is becoming more and more important to develop not only efficient but also quiet fan stages. In this paper the noise emission of a fan for an aero-engine with a bypass ratio of 19 is reduced within a multidisciplinary design optimization (MDO) by means of an hybrid noise prediction method while at the same time optimizing the aerodynamic efficiency. The aerodynamic performance of each configuration in the optimization is evaluated by stationary Reynolds-Averaged Navier-Stokes (RANS) simulations. These stationary flow simulations are also used to extract the aerodynamic excitation sources for the analytical fan noise prediction. The resulting large database of the optimization provides new insights into which extent an MDO can contribute to the design of both quiet and efficient fan stages. In addition to that the hybrid approach of numerical flow solutions and analytical description of the noise sources enables to understand the noise reduction mechanisms. In particular, the influence of rotor blade loading on the aerodynamic efficiency and the noise sources as well as the potential of configurations with a comparatively low number of outlet guide vanes (OGV) is explored. The acoustic results of selected configurations are confirmed by unsteady RANS simulations.

Noise pollution is one of the major concerns in big cities as well as in the crowded area of small cites, Gorakhpur is fastgrowing city and has many locations with high noise levels. Various crossroads and intersections have traffic issues this causes high noise level. In this study, three locations were selected for noise level assessment, nearby areas of Gorakhnath Temple, BRD medical college and MMMUT. These locations are educational (silent) and low noise level zone but because they situated near traffic roads, which cause high noise levels around them. In this study outside periphery of educational institutions noise level increases due to traffic. Noise level is found to be high due to large number of human activities.

The work reports on the design of an area-efficient inductor-less low-noise CMOS transimpedance amplifier suitable for entry-level optical time-domain reflectometers. The work suggests a novel approach for implementing a programmable-gain in capacitive feedback TIA with an independent adjustment of the low- and high-frequency behavior using the input stage biasing impedance and one of the feedback capacitors. The approach addresses a typical noise problem of fast feed-forward or resistive feedback topologies while alleviating the trade-off of the key TIA performance indicators. A more accurate amplifier model is proposed which takes into account the effects due to capacitive isolation and both biasing circuits. Further modifications to the reference design are suggested including the PMOS-based implementation of the biasing circuit to address the voltage headroom issue. The circuit was implemented using a standard 180 nm CMOS process and operates from 1.8 V supply with the drawn current of 11.7 mA.

OCR (Optical Character Recognition) for scanned paper invoices is very challenging due to the variability of 19 invoice layouts, different information fields, large data tables, and low scanning quality. In this case, table structure recognition is a critical task in which all rows, columns, and cells must be accurately positioned and extracted. Existing methods such as DeepDeSRT only dealt with high-quality born-digital images (e.g., PDF) with low noise and apparent table structure. This paper proposes an efficient method called CluSTi (Clustering method for recognition of the Structure of Tables in invoice scanned Images). The contributions of CluSTi are three-fold. Firstly, it removes heavy noises in the table images using a clustering algorithm. Secondly, it extracts all text boxes using state-of-the-art text recognition. Thirdly, based on the horizontal and vertical clustering algorithm with optimized parameters, CluSTi groups the text boxes into their correct rows and columns, respectively. The method was evaluated on three datasets: i) 397 public scanned images; ii) 193 PDF document images from ICDAR 2013 competition dataset; and iii) 281 PDF document images from ICDAR 2019’s numeric tables. The evaluation results showed that CluSTi achieved an F1-score of 87.5%, 98.5%, and 94.5%, respectively. Our method also outperformed DeepDeSRT with an F1-score of 91.44% on only 34 images from the ICDAR 2013 competition dataset. To the best of our knowledge, CluSTi is the first method to tackle the table structure recognition problem on scanned images.

This work Demonstrates a wideband LNA for 5G receiver front end modules with high linearity, Low noise reused topology has an inter stage wideband inductor based two common source cascade stages. The configuration provides the bias current; better Noise figure increases the forward gain. By providing RC Series network at gate terminal of second stage the return losses are reduced and stability will be increased. After pre and post simulation all parameters are better than the existing LNAS. After post simulation results, the Noise figure is achieved less than 1dB and forward gain as flat 16dB for wide band width of 1.5 – 5.5 GHz. At the 1dB compression point the output is 20dbm achieved and OIP3 IS +40dbm is achieved. The chip size of an LNA along with pad is 0.64mm2. The design is GaAsp HEMT process at 50nm technology.

There is adequate evidence from epidemiological studies showing an association between noise exposures and incidence of cardiovascular diseases and cognitive impairment among exposed populations. This study aimed to investigate noise exposure levels in an airport region and their effects on the nearby two neighborhood communities (i.e., Al Seeb and Bawshar). To achieve this, noise levels were measured across 15 different points within the communities for more than 3 weeks at a median distance of 3.5 km from the airport runways using a sound level analyzer. In addition, we conducted an online social survey in a random sampling of a total of 913 residents who were living closer to the airport. A combination of a 5-point scale and 3-point Likert scale was used to assess the resident population’s noise annoyance and the potential health impacts. The results revealed that the majority of the measured points have noise levels (55.71–65.24 LAeq dBA) exceeding both Oman and WHO critical limits. There was a general decrease in noise levels at points further away from the runways; thus, at points 2.5, 4.8, and 8.8 km, sound pressure levels were found to be 63.08, 57.41, and 52.31 dBA, respectively. However, steady noise levels were observed throughout most of the daily (24 h) measurements indicating continual exposures. Overall, 44.6% of residents reported noise annoyance level as very high, with Al Seeb inhabitants (46%) eliciting a greater percentage of annoyance levels compared to Bawshar (5%) due to their closer proximity to the airport. Also, the noise was significantly (p ˂ 0.001) associated with sleep disturbance, insomnia, irritation, and frightening. The majority of the residents complained of an increase in insomnia (41.5%), stress (34.3%), headache (47.3%), and cardiovascular diseases (16.2%). With the question of reducing noise exposures, about 41% of the respondents have plans of relocating to distant areas with low noise levels.

Semiconductor deposition on magnetron's cathode surface using different materials such as gallium nitride (GaN) and silicon carbide (SiC) semiconductors is conducted to grow approximately 80, 100 and 120 nm plasma layers. The cathode is then used to generate high frequency and low-power microwave for further comparison and analysis with the conventional magnetron operation. Parameter of analysis to identify the efficiency includes electron drift velocity, harmonic order, total harmonic distortion, low harmonic distortion, and spectrum observation. The sputtered cathode of the magnetron is used to generate a low-power microwave observing a generator efficiency up to 93 and 88% for GaN and SiC materials, respectively, compared to the conventional material, which observes 37% of efficiency at 2450 MHz, 5 W. Also reported is the quality of semiconductor sputtering on the magnetron cathode, which was manipulated by the deposition period, temperature, and plasma layer growth thickness.

In this article, a wideband quasi-circulator (QC) with the low noise figure (NF) and high 1-dB compression point ( $\text{P}_{\text {1 dB}}$ ) is proposed. The slotline-based 180° hybrid is introduced to achieve the wideband high transmitter-receiver (TX-RX) isolation. Meanwhile, the bidirectional in-phase stage and the nonreciprocal out-of-phase stage are utilized to obtain specific power-split ratios for the low insertion loss and high antenna-transmitter (ANT-TX) isolation. By using the unequal power split, the proposed QC is without the fundamental 3-dB loss seen in reciprocal ANT interfaces. Besides, to further enhance the TX-RX isolation within a wideband, a reconfigurable inter-stage matching network based on a varactor-tuned capacitor is implemented. To verify the mechanisms mentioned above, a reconfigurable wideband QC operating at 1.75–2.9 GHz is implemented and fabricated. The total power consumption is 224 mW. The measurement exhibits in-band TX-RX isolation of 27–58 dB. The TX-ANT and ANT-RX insertion losses are 4.3–5.0 dB and 1.0–1.9 dB, respectively. The QC also achieves the minimum in-band ANT-RX NF of 3.4 dB. Meanwhile, the measured TX-ANT and ANT-RX IIP3s are 39.4 and 32.5 dBm, respectively. The TX input $\text{P}_{\text {1 dB}}$ is greater than 28.78 dBm, while the RX input $\text{P}_{\text {1 dB}}$ is 23 dBm. The TX-induced ANT-RX $\text{P}_{\text {1 dB}}$ is measured to be 28 dBm.

InGaAs/InP single-photon avalanche diode (SPAD) with small active diameter and backside microlens was fabricated and its dark count and after-pulse noises were characterized. In addition, by optimizing multiplication layer and reducing the active diameter, high photon detection efficiency (PDE) was achieved as well as suppressed dark count probability (DCP) and after-pulse probability (APP) near room temperature. The gated Geiger-mode characteristics of SPAD were investigated with the gate amplitude of 6.6 V and repetition frequency of 10 MHz. Superior single-photon detection characteristics as PDE of 20.9%, DCP of 1.02 × 10–5 and APP of 0.8% were observed at the operation temperature of + 20 °C. It is a promising result that allows compact and low-cost detector module for quantum key distribution system with simple cooling apparatus.

As an effective capacitance signal produced by a micro-hemisphere gyro is usually below the pF level, and the capacitance reading process is susceptible to parasitic capacitance and environmental noise, it is highly difficult to acquire an effective capacitance signal. Reducing and suppressing noise in the gyro capacitance detection circuit is a key means to improve the performance of detecting the weak capacitance generated by MEMS gyros. In this paper, we propose a novel capacitance detection circuit, where three different means are utilized to achieve noise reduction. Firstly, the input common-mode feedback is applied to the circuit to solve the input common-mode voltage drift caused by both parasitic capacitance and gain capacitance. Secondly, a low-noise, high-gain amplifier is used to reduce the equivalent input noise. Thirdly, the modulator–demodulator and filter are introduced to the proposed circuit to effectively mitigate the side effects of noise; thus, the accuracy of capacitance detection can be further improved. The experimental results show that with the input voltage of 6 V, the newly designed circuit produces an output dynamic range of 102 dB and the output voltage noise of 5.69 nV/√Hz, achieving a sensitivity of 12.53 V/pF.

This paper presents a capacitively coupled chopper instrumentation amplifier (CCIA) with ultra-low power consumption and programmable bandwidth for biomedical applications. To achieve a flexible bandwidth from 0.2 to 10 kHz without additional power consumption, a programmable Miller compensation technique was proposed and used in the CCIA. By using a Squeezed inverter amplifier (SQI) that employs a 0.2-V supply, the proposed CCIA addresses the primary noise source in the first stage, resulting in high noise power efficiency. The proposed CCIA is designed using a 0.18 µm CMOS technology process and has a chip area of 0.083 mm2. With a power consumption of 0.47 µW at 0.2 and 0.8 V supply, the proposed amplifier architecture achieves a thermal noise of 28 nV/√Hz, an input-related noise (IRN) of 0.9 µVrms, a closed-loop gain (AV) of 40 dB, a power supply rejection ratio (PSRR) of 87.6 dB, and a common-mode rejection ratio (CMRR) of 117.7 dB according to post-simulation data. The proposed CCIA achieves a noise efficiency factor (NEF) of 1.47 and a power efficiency factor (PEF) of 0.56, which allows comparison with the latest research results.

К современным гидравлическим системам предъявляются жесткие требования по шуму и вибрации. В имеющемся объеме работ много внимания уделяется большому количеству факторов, зачастую без учета их взаимовлияния. В общем случае их можно разделить на схемно-конструктивные, системные и принципиальные решения. В настоящее время развитие науки и техники находится на том уровне, когда дальнейшее улучшение акустического качества отдельных элементов и систем в целом возможно при исследовании возникающих процессов на стыке наук. В связи с этим в работе рассматриваются возможности моделирования волновых процессов в гидравлических системах управления с последующим получением акустических характеристик, что представляет собой совместное использование математического аппарата теории управления и методов акустики. В качестве одного из наиболее подходящих средств решения поставленных задач в работе рассматривается программный комплекс Simhydraulics Matlab. Наряду с математическими моделями элементов системы управления в работе предложены акустические модели элементов, которые учитываются при моделировании переходных процессов в системе. На основе полученных результатов предлагаются дополнительные критерии оценки качества систем управления.

This paper introduces a high-speed mixed-signal readout array in 130-nm CMOS for the amplification and digitization of picoampere-range signals. Its design is inspired by the needs of emerging DNA sequencing technologies based on biological nanopore sensors. To overcome switching and substrate noise this system adopts an in-pixel analog-to-digital converter (ADC) architecture and a novel readout technique while consuming 10x less power than similar designs described in the literature. The in-pixel ADC architecture is inherently scalable and immune to electrical interference which can be extended to 100s of channels. With a 5 pF input capacitance, the amplifiers achieve a maximum bandwidth of 100 kHz and demonstrate a noise floor as low as 4 fA/ $\sqrt {\text{Hz}}$ and a gain in the range of $\text{G}\Omega $ at 10 kHz. Circuit noise behaviour and theoretical maximum performance estimates using behavioural models are also discussed.

The triple-frequency linear combination with a low noise, a long wavelength, and a weak ionosphere is beneficial to effectively eliminate or weaken the common errors, advance the reliability of cycle slip detection and repair, and speed up the convergence time of fixed ambiguity. By establishing the Galileo triple-frequency carrier linear combination model, three types of linear combinations are derived: Geometry-free (GF) combinations, minimum noise (MN) combinations, and ionosphere-free (IF) combinations. The geometric relationships of these linear combinations are displayed in the form of image. The results indicate that the angle formed by the IF combinations and the MN combinations is between 75.02° and 86.01°, which also illustrates that it is more difficult to meet the carrier phase combinations with a low noise and a weak ionosphere. Moreover, to guarantee the integer cycle characteristics of ambiguity, the combination coefficient must be an integer. Galileo triple-frequency linear combination is solved utilizing the extremum method. To sum up, the sum of the coefficients of the extra wide lane (EWL) combinations and wide lane (WL) combinations is zero, and the sum of the coefficients of the narrow lane (NL) combinations is one. (0, 1, −1) is the optimal triple-frequency linear combination in Galileo. Three independent linear combinations are selected separately from the EWL, WL, and NL to jointly solve the integer ambiguity. Further, it creates a prerequisite for high-precision and real-time kinematic positioning.

This article presents a complete design flow of a low noise transimpedance amplifier for 10 Gbps optoelectronic receivers. The proposed topology is based on the shunt-shunt structure with negative feedback. A set of equations was deduced from the frequency analysis and noise analysis. An optimization algorithm is proposed in order to maximize the bandwidth and improve the noise performance simultaneously. Experimental results shown a 51 dBΩ transimpedance gain, a 10.54 Ghz bandwidth and an input referred current noise equal to 6.8, the lowest one between other state-of-art designs. The circuit was manufactured in 130 nm RF CMOS technology.

This paper presents an optimisation approach for designing low-noise Outlet Guide Vanes (OGVs) for fan broadband noise generated due to the interaction of turbulence and a cascade of 2-dimensional aerofoils. The paper demonstrates the usage of Bayesian optimisation with constraints to reduce the computation cost of optimisation. The prediction is based on Fourier synthesis of the impinging turbulence and the aerofoil response is predicted for each vortical modal component. A linearised unsteady Navier-Stokes solver is used to predict the aerofoil response due to an incoming harmonic vortical gust. This paper shows that to achieve noise reductions of 0.5 dB the penalty on the aerodynamic performance of 33% is observed compared to baseline aerofoil. Hence, the geometry changes such as thickness and nose radius can’t reduce broadband noise without effecting aerodynamic performance.

The problem of broadband matching of active elements in terms of noise figure is inevitably encountered in the design of broadband low-noise microwave amplifiers. Despite the fact that this problem differs from the classical problem of broadband matching of signal source and load, it can be reduced to a form suitable for applying methods for solving the classical problem. For this purpose, in this work, the own parameters of a reactive two-port network are derived that match active elements in terms of noise figure in the entire frequency band, where the data for calculating this coefficient are determined. The own parameters of such a two-port network, on the one hand, make it possible to construct methods for the synthesis of input matching circuits of low-noise amplifiers and other devices where low noise matching is required. On the other hand, the own parameters allow one to construct estimates of the maximum achievable bandwidth for a matching circuit of a given complexity.

"Regarding the increasing demands for a low noise environment onboard ships, the classification societies introduced the measurement of noise levels onboard every ship not only for the first ship, no matter the type and size above 1600 gross tonnage. That why is necessary a good collaboration of all the parties involved in the construction of ships from designers, shipbuilders, till owners. This article describes the measurements technique used for obtaining the noise levels onboard a cargo vessel, to obtain the approval of Classification society-"

This paper presents a comprehensive TCAD based assessment to evaluate the intrinsic gain and minimum noise figure metrics of the T – Gate, and the π – Gate AlGaN/AlN/GaN HEMTs along with their recessed architectures. The work presented in this paper, to the best of author’s knowledge, is first in its attempt to systematically bring out both the effect of minimum noise figure metrics and intrinsic gain at the device level for the π – Gate architecture and their recessed counterparts whilst evaluating its stability for high frequency operations. Comparison demonstrates an enhancement in intrinsic gain by 64.5% in case of asymmetric π – Gate and 77% for asymmetric recessed π – Gate in comparison to their T – Gate counterparts. Further, the said architectures possess a wider range of flat gain operation with suppressed values of minimum noise figure metrics. These modifications result in a modest trade off in the minimum noise figures when best case is considered and compared with their T – Gate counterparts. Additionally, it is also demonstrated that such device architectures demonstrate much stable high frequency operation in comparison to their primer. The results so presented establish the superiority of the π – Gate AlGaN/AlN/GaN HEMTs for low noise and high gain applications.