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For short-range applications, the intensity modulation/direct detection (IM/DD) technique is preferred because of its low cost, small size, and simplicity. However, when the data rate rises to 100 Gbps or more, signal distortion brought on by low-cost components and fiber dispersion leads to system performance limitations. In this study, we show that an artificial neural network (ANN) based equalizer is a more efficient way to enhance the transmission performance of high-speed IM/DD systems than traditional methods. Furthermore, a 50 Gbaud PAM4 communication system's overall performance can be improved by an ANN-based equalizer with low complexity. When compared to the conventional feed-forward equalizer (FFE), the simulation results for the 50 Gbaud system using the ANN equalizer generally demonstrate better performance. [ABSTRACT FROM AUTHOR]

The present article presents critical aspects of RF system development process and its sequential phases along with associated challenges. It also discusses importance of active and passive components thermal behavior and their impact in overall system performance. The study on performance deviation of these components with temperature change has been reported. Potential issues for gain variation and frequency selectivity have been analysed and suitable solutions are explored accordingly. Implementation of temperature stabilization method in designed RF product has been carried out during prototype development. Practical achieved results are noted down during testing and measurement to monitor effectiveness of thermal stabilization mentioned in it. Finally, wideband flat gain response has been achieved by implementation of thermal stabilization for active and passive components to avoid any performance degradation. [ABSTRACT FROM AUTHOR]

Relatedness is necessary and causal in the development of social life. Interlayer relatedness is a measure of how one player’s decisions affect the decisions of other players in the game. The relatedness can be positive or negative. We had to determine how effective each strategy was under specific conditions, and how the correlation between players affected their payoffs. In this paper, we analytically study the strategies that enforce linear payoff relationships in the Iterated Prisoner’s Dilemma (IPD) game considering both a relatedness factor. As a result, we first reveal that the payoffs of two players and three players can be represented by the form of determinants as shown by Press and Dyson even with the factor. [ABSTRACT FROM AUTHOR]

The traditional Buck-Boost equalization circuit has long transmission path and low equalization efficiency, and the existing ring equalizer cannot fundamentally solve this problem. In view of this problem, a double-layer ring equalizer for lithium battery based on Buck-Boost and switched capacitor is proposed in this study. The equalization circuit adopts modular balancing method, and adopts Buck-Boost and switching capacitor hybrid circuit to achieve equalization in the bottom module and top module. The circuit structure is analyzed from two aspects of equalization speed and efficiency by graph theory analysis. The results show that the equalization circuit has the advantages of less energy transmission paths and high energy transmission efficiency. The simulation model of the equalization circuit is built on the MATLAB/Simulink power simulation platform. The simulation results show that the equalization speed of the double-layer ring equalizer based on Buck-Boost and switched capacitor is 46% higher than that of the single-layer ring equalizer. Additionally, an experimental prototype of four batteries is established to verify the working principle and system equalization efficiency of the ring equalization circuit. The experimental results show that the equalization efficiency of the double-layer ring equalizer is 26.78% higher than that of single-layer ring equalizer. The simulation and experimental results are consistent with the theoretical analysis, which indicates that the circuit structure is reasonable and effective. [ABSTRACT FROM AUTHOR]

An eye diagram, a critical metric in signal integrity analysis for high-speed interconnects such as packages, interposer, and printed circuit boards (PCBs), is generated by superposition of the received waveform. Obtaining an eye diagram is time-consuming, thus signal integrity analysis is inefficient. This article reviews that have been proposed to overcome this limitation. The statistical eye diagram provides a probability distribution depending on a sampling time and voltage, therefore it can be expanded to other metrics, such as the bit-error rate and shmoo plot. This article introduces previous research on statistical eye diagrams applied to complementary metal-oxide-semiconductors (CMOSs), noise, and high-speed systems. The methods applied to CMOSs include asymmetry between the P/NMOS transistors and the nonlinearity of the CMOS. The methods applied to noise include signal and power noise. The methods applied to high-speed systems include equalizers, signaling, encoding, linear feedback shift register, and error correction code.

Summary: This paper proposes a wireline serial link transceiver for on‐package die‐to‐die links based on 12‐nm fin field‐effect transistor (FinFET) technology. The link is crucial for improving the computational performance of larger systems built from chiplets. To achieve high pin/energy efficiency and prevent traditional single‐ended signaling disadvantages, the transceiver adopts single‐ended ground‐reference signaling (GRS) to transfer information. To precompensate for the frequency‐dependent loss, retain the advantages of GRS, and avoid the disadvantages of traditional AC‐coupled equalizer, the transmitter in the transceiver adopts a DC‐coupled switched‐capacitor charge pump equalizer that can transmit GRS and its equilibrium value can be adjusted according to the channel attenuation. This paper proposes a method for timing de‐skew using digital control delay lines to eliminate the timing skew between data and the clock. In addition, this paper presents a duty cycle corrector to avoid duty cycle distortion, with an adjustment range of 44.5% to 52% and a power dissipation of only 30 μW. The transceiver has an area of 1.016 × 0.676 mm2, including one clock lane link and four data lane links. At a nominal 0.8‐V power supply voltage, the aggregate eye‐opening of the measured 25 Gb/s data on an organic substrate channel with an attenuation of −2.2 dB over 6 mm is 0.675 UI, with a bit error rate (BER) of less than 10−12 and an energy efficiency of 1.01 pJ/bit. [ABSTRACT FROM AUTHOR]

Central data systems require mass storage systems for big data from many fields and devices. Several technologies have been proposed to meet this demand. Holographic data storage (HDS) is at the forefront of data storage innovation and exploits the extraordinary characteristics of light to encode and retrieve two-dimensional (2D) data from holographic volume media. Nevertheless, a formidable challenge exists in the form of 2D interference that is a by-product of hologram dispersion during data retrieval and is a substantial barrier to the reliability and efficiency of HDS systems. To solve these problems, an equalizer and target are applied to HDS systems. However, in previous studies, the equalizer acted only as a linear convolution filter for the received signal. In this study, we propose a nonlinear equalizer using a convolutional neural network (CNN) for HDS systems. Using a CNN-based equalizer, the received signal can be nonlinearly converted into the desired signal with higher accuracy. In the experiments, our proposed model achieved a gain of approximately 2.5 dB in contrast to conventional models. [ABSTRACT FROM AUTHOR]

We study statistics of signal power spectrum ripple in a chain of erbium-doped fiber amplifiers (EDFAs). It is found that allowance for the statistical properties of EDFA gain ripple can markedly increase the accuracy of estimating the magnitude of spectrum ripple of a multichannel signal (by 4 dB in a chain of five EDFAs). By analyzing the simulation results for various configurations of fiber-optic communication lines (FOCLs), an optimal equalizer spacing period is estimated. It is shown that the signal quality deterioration in a FOCL caused by the EDFA gain ripple depends on the number of spans between devices flattening the signal spectrum, and on statistical characteristics of gain spectrum ripple of the used EDFAs; however it is practically independent of the number of spectrum equalizing sections, signal parameters, and span length. The simulation results are used to construct a model for calculating the penalty from accumulated EDFA ripple. An algorithm is proposed for estimating the penalty, applicable for an arbitrary FOCL configuration with known statistics of EDFA accumulation ripple. [ABSTRACT FROM AUTHOR]

It was shown by Banaschewski and Pultr that the classical adjunction between Top and Loc restricts to an adjunction between the category TopD of TD-spaces and their continuous maps, and the category LocD of all locales and localic maps which preserve coveredness of primes. Despite the fact that LocD plays an important role in the TD-duality, not much is known about its categorical structure, and it is the aim of this paper to fill this gap. In particular, we show that LocD is closed under finite products in Loc and moreover we characterize the existence of equalizers. As a consequence, it is proved that regular monomorphisms in LocD are precisely the D-sublocales — the notion analogue to sublocale in the TD-duality — a situation akin to the standard fact that sublocales are precisely regular monomorphisms in Loc. The results are then applied to obtain the TD-analogues of some familiar results for sober spaces and some new characterizations of TD-spatiality of localic squares in terms of certain discrete covers of locales. [ABSTRACT FROM AUTHOR]

Accurate measurement of angular positions on the sky requires a well-defined system of reference, something that in practice is realized by the International Celestial Reference Frame (ICRF) with observations of distant (typical redshift $\sim$1) Active Galactic Nuclei (AGN). At such great distances a subset of these objects exhibit as little as 10$-$50 $\mu$as/year observed parallax or proper motion, thus giving the frame excellent spatial and temporal stability. Until fairly recently the majority of AGN centered imaging was accomplished in the S (2.3 GHz) and X (8.4 GHz) radio frequency bands, however S-band observations for reasons such as sensitivity “plateauing”, increased source structure (jets), and radio frequency interference (RFI) have become less productive. Following spacecraft telemetry moves to higher frequencies and a desire to strengthen JPL's leadership in defining the next-generation of celestial reference frames has motivated the development of a “Quad-band” prototype receiver that operates in X, Ku, K, and Ka band in both right hand (RCP) and left hand (LCP) circular polarization. The goal of this receiver is to achieve less than a 20 % increase in noise over the Jansky Very Large Array (JVLA, NRAO) performance specification, which in such a wide bandwidth represents a revolutionary capability. To evaluate the various technical developments of the 8 GHz$-$40 GHz receiver the feedhorn optical beam was designed to interface to the US based Very Long Baseline Array (VLBA). The receiver's intermediate frequency (IF) spans 4 GHz$-$8 GHz, giving rise to up to eight 4 GHz IF channels for a fully populated instrument. This paper outlines the technical development of a 2$^{1}$/$_{2}$ octave wide (8 GHz$-$40 GHz) X-Ka band prototype receiver, fulfilling a need for super broadband technology within the VLBI network. An important additional benefit of the wideband receiver approach is its simplicity and low cost of operation.

An overshoot generated in the optical fiber communication system's transmitter may degrade bit error ratio performance and even damage the device. This overshoot is caused by the output capacitance of driver, the parasitic inductance of bonding wire, and vertical-cavity surface-emitting laser (VCSEL). This paper introduces a 25Gb/s VCSEL driver using a current-mode pre-equalization technique to suppress overshoot. The driver is designed in 0.13 μ m SiGe BiCMOS technology. The post-simulation results show that the pre-equalization technique applied to the driver can suppress the overshoot in the VCSEL output waveform. The measurement results show that the VCSEL driver can output an electrical eye diagram to suppress the overshoot. The core area of the VCSEL driver chip is 0.305 mm × 1.207 mm, including driver circuit, delay circuit, bandgap reference circuit, and digital-to-analog converter. [ABSTRACT FROM AUTHOR]

Central data systems require mass storage systems for big data from many fields and devices. Several technologies have been proposed to meet this demand. Holographic data storage (HDS) is at the forefront of data storage innovation and exploits the extraordinary characteristics of light to encode and retrieve two-dimensional (2D) data from holographic volume media. Nevertheless, a formidable challenge exists in the form of 2D interference that is a by-product of hologram dispersion during data retrieval and is a substantial barrier to the reliability and efficiency of HDS systems. To solve these problems, an equalizer and target are applied to HDS systems. However, in previous studies, the equalizer acted only as a linear convolution filter for the received signal. In this study, we propose a nonlinear equalizer using a convolutional neural network (CNN) for HDS systems. Using a CNN-based equalizer, the received signal can be nonlinearly converted into the desired signal with higher accuracy. In the experiments, our proposed model achieved a gain of approximately 2.5 dB in contrast to conventional models.

After they reached the end of their useful EV life, lithium-ion batteries are still satisfactory for second life (SL) energy storage applications. However, the spread in their SL cell capacities may be much wider than in the EV, and this raises a question as to what type of cell voltage equalizer (EQU) should be used. Most users plan to retain the same passive EQU (PEQ) from the EV, but this means the battery capacity will be the same as the worst cell in the battery, just as it was in the EV. Unfortunately, the SL cell capacity spread may be much wider than it was in the EV, and if so, most of the cells will be under-utilized. This can be corrected by using an active EQU (AEQ) or a hybrid, such as the bilevel EQU (BEQ), to provide a capacity close to the cell average; but first, measured data is needed on the actual size of the cell capacity spread. To simplify and reduce the cost of these measurements, a new method is proposed that provides the capacities of the worst cell and the cell average.

A completely distributive complete lattice is called a molecular lattice. It is well known that the category TML of all topological molecular lattices with generalized order homomorphisms in the sense of Wang, is both complete and cocomplete. In this note, we give an example which shows that the structure of equalizers introduced by Zhao need not be true, in general. In particular, we present the structures of equalizers, coequalizers, monomorphisms and epimorphisms in this category. [ABSTRACT FROM AUTHOR]

The equalizers available are difficult to give consideration to both high balance efficiency and fast balance speed, and their performances are unstable as the number of the series‐connected batteries increases, so they are unsuitable for a large‐scale battery system. A multi‐objective parallel layered equalizer based on battery working states for the large‐scale lithium‐ion battery system is presented. The equalizer has two types of balance objects and two corresponding layers, and the first layer and the second layer take the single battery and the battery unit as the balance object, respectively. The multi‐objective parallel layered balance means that multiple balance objects are selected as the balance objectives simultaneously at each layer. The balance speed is fast due to the multi‐objective parallel balance. The balance efficiency is high due to the short energy path and the complementary pulse width modulation (PWM) control in the first layer, and the double voltage value of the balance object in the second layer. Moreover, the performance of the equalizer is stable, even when the number of series‐connected batteries is large. In short, the proposed equalizer features high efficiency, fast speed, and strong scalability. Further, the experimental platform for a battery system with twelve series‐connected lithium‐ion phosphate batteries is built, and then the balance experiments have been completed. Finally, the effectiveness of the equalizer is verified by the corresponding experimental results. [ABSTRACT FROM AUTHOR]

In this article, a novel systematic method for compensation of the simultaneous amplitude and group delay (GD) flatness in the narrowband bandpass filters is proposed. The proposed technique can be used systematically in any type of filters with the possibility of resonator quality factor adjustment. This technique is presented using an RLC resonator equalizer in two steps. First, the compensation of the GD response is accomplished by tuning the external Q‐factor, then the amplitude response is compensated by adjusting the resonator Q‐factor. To verify this technique, design and fabrication of a TM dual‐mode equalizer for joint compensation of the amplitude and GD responses in a narrowband waveguide filter is presented. The simulation results for a novel TE dual mode equalizer is also presented. The passband response of an un‐equalized narrowband filter with passband flatness of 1.5 dB amplitude and 55 ns GD at the center frequency of 10.970 GHz is improved to 0.5 dB amplitude flatness and 30 ns GD flatness. This improvement is achieved at the cost of passband insertion loss. The designed equalizer is fabricated and tested and the measurement results, after and before equalization, prove the design technique capability. [ABSTRACT FROM AUTHOR]

Multi-rope elevators are widely used in modern buildings. However, problems such as vibration, noise, uneven wear of key components and shortened life caused by the uneven distribution of rope tensions are still unsolved in the elevator industry. In order to balance the different tensions and the axial deformation of each rope, a novel automatic balance equipment for rope-type elevators (NABE-RE) is proposed in this article. Simulations based on the Simscape numerical methodology are used to verify the kinematic rationality of the proposed mechanism. The optimal structural stability of the core components is evaluated through a series of investigations based on the finite element method. Additionally, the manufactured prototypes are put through a series of comparison experiments to evaluate their tension balancing performance. The results show that the unbalance rate of the system is effectively limited to a low level, thus verifying the feasibility of the automatic tension balancing function of the proposed NABE-RE. [ABSTRACT FROM AUTHOR]

Recently published CMOS optical receivers consist of a limited-bandwidth first-stage transimpedance amplifier (TIA) followed by an equalizer. Limiting the TIA’s bandwidth improves the gain and reduces the noise but introduces a significant inter-symbol interference (ISI) that is dealt with by the subsequent equalizer. Continuous-time linear equalizer (CTLE) is a commonly used equalizer in both electrical and optical links. However, recent research reported different findings about CTLE-based optical receivers. Some research papers concluded that CTLEs boost high-frequency noise compared to a full-bandwidth design. Other publications reported that high-frequency noise remains unaffected while white noise is significantly reduced. This work aims to solve this discrepancy by presenting an accurate analysis for CTLE-based optical receivers considering noise, gain, and jitter. We show that the noise performance depends on the pole/zero locations of the limited-bandwidth (LBW)-TIA and the follow-on equalizer. A properly designed CTLE-based receiver achieves a $2.5 \times $ higher gain and a $1.74\times $ better noise than the full-bandwidth design. The CTLE is also compared to the well-known decision feedback equalizer (DFE). The noise performance of the CTLE-based receiver lies between that of finite and infinite impulse response DFE-based receivers but achieves better gain than both architectures.

Design and assessment of THz communications systems, which will form an essential part of 6G, require an understanding of the propagation channels the systems will operate in. This paper presents investigations of the channel characteristics in various scenarios at 145 GHz, which is the band currently envisioned for the first round of deployments. In particular, we review several extensive measurement campaigns performed by the University of Southern California in both outdoor and indoor environments. We present the measurement and evaluation methodology and sample results that illustrate the dominant propagation effects in different environments. We then summarize the parameters of the statistical channel models for path loss, delay dispersion, and angular dispersion. Based on these results, we find that even in NLoS (non-line-of-sight) situations, Gbit/s communications can be sustained over a 100 m distance; that (for an antenna gain of 20 dB), there is considerable delay dispersion, requiring tens of equalizer taps, and that angular dispersion is significant in both LoS and NLoS situations. The channel parameters can be thus used as a basis for system design and evaluation under realistic operating conditions.

This paper proposes a new method to design the fixed single-channel equalizer parameters based on perceptual evaluation of speech quality (PESQ) and the short-time objective intelligibility (STOI). The proposed equalizer does not require the need for noise estimation nor a voice activity detector. The fixed weightings are obtained by a training process containing a set of training data. A multi-objective optimization problem was formulated with the PESQ and STOI as the objective measures, which results in a set of candidate solutions via the Pareto optimality. Experimental results demonstrate improvements in PESQ and STOI, and the trade-off between these two measures is well defined in a set of Pareto optimal solutions to allow flexible adjustment. [ABSTRACT FROM AUTHOR]

The advent of zero-determinant (ZD) strategies has reshaped the study of reciprocity and cooperation in the iterated prisoner’s dilemma games. The ramification of ZD strategies has been demonstrated through their ability to unilaterally enforce a linear relationship between their own average payoff and that of their co-player. Common practice conveniently represents this relationship by a straight line in the parametric plot of pairwise payoffs. Yet little attention has been paid to studying the actual geometry of the strategy space of all admissible ZD strategies. Here, our work offers intuitive geometric relationships between different classes of ZD strategies as well as nontrivial geometric interpretations of their specific parameterizations. Adaptive dynamics of ZD strategies further reveals the unforeseen connection between general ZD strategies and the so-called equalizers that can set any co-player’s payoff to a fixed value. We show that the class of equalizers forming a hyperplane is the critical equilibrium manifold, only part of which is stable. The same hyperplane is also a separatrix of the cooperation-enhancing region where the optimum response is to increase cooperation for each of the four payoff outcomes. Our results shed light on the simple but elegant geometry of ZD strategies that is previously overlooked. [ABSTRACT FROM AUTHOR]

This study exploratively conducted two investigations of timbre influenced by harmonic loudness. Investigation 1 examined piano timbre preference between non-processed melodies and two kinds of adjustments created via an equalizer–a basic tool used for sound engineering and for producing audio materials. Using the paired comparison method, 98 respondents were surveyed. The results show that in the bass range of the piano sound, the preferred audio material was that produced via an equalizer by reducing the loudness of the 7th and 9th harmonics by 15 dB, while enhancing the loudness of the 8th harmonic by 15 dB. Investigation 2 examined three degrees of the processed melodies—adjusting the harmonics by 15, 10, and 5 dB. The results show that the 15 dB change was the best, while the 10 dB change was the worst. These results provide a new approach to improving the sound timbre for sound engineering and artificial intelligence music production. [ABSTRACT FROM AUTHOR]

After they reached the end of their useful EV life, lithium-ion batteries are still satisfactory for second life (SL) energy storage applications. However, the spread in their SL cell capacities may be much wider than in the EV, and this raises a question as to what type of cell voltage equalizer (EQU) should be used. Most users plan to retain the same passive EQU (PEQ) from the EV, but this means the battery capacity will be the same as the worst cell in the battery, just as it was in the EV. Unfortunately, the SL cell capacity spread may be much wider than it was in the EV, and if so, most of the cells will be under-utilized. This can be corrected by using an active EQU (AEQ) or a hybrid, such as the bilevel EQU (BEQ), to provide a capacity close to the cell average; but first, measured data is needed on the actual size of the cell capacity spread. To simplify and reduce the cost of these measurements, a new method is proposed that provides the capacities of the worst cell and the cell average. [ABSTRACT FROM AUTHOR]

A broadband W-band microwave power module (MPM) is demonstrated. It provides a continuous wave (CW) output power of 65 W from 91 to 97 GHz with a constant driving power of 0 dBm. The MPM consists of a miniaturized folded-waveguide traveling-wave tube (TWT), an integrated power conditioner (IPC), and a gain equalizing solid-state amplifier (GE-SSA). The overall efficiency exceeds 20 % and the saturation gain fluctuation is lower than 0.8 dB. It has dimensions of 380 mm $\times$ 180 mm $\times$ 45 mm and a weight of 5.5 kg. [ABSTRACT FROM AUTHOR]

In bit-patterned media recording (BPMR) systems, two-dimensional (2D) interference, which includes intersymbol and intertrack interference from down- and across-track directions, respectively, increases when the distance between the islands is reduced with increasing areal density. In recent studies, a general partial response (GPR) target was often deployed with the equalizer to estimate and reduce interference. With this combination, the BPMR system becomes a promising candidate for high-density storage systems and achieves high bit error rate (BER) performance. Therefore, in this study, we investigate the detection capability while varying the form of the GPR target and implement a multilayered 2D GPR target and a detection method for improving the accuracy in estimating the interference. The simulation results demonstrate that the proposed model improves by a gain of ~1 dB compared to the previous studies. [ABSTRACT FROM AUTHOR]

Noise probably the single most important performance metric of the high-speed transimpedance amplifier (TIA), which directly sets the sensitivity of optical receiver. The transimpedance limit which dictates the maximum achievable transimpedance gain of the TIA also turns out to fundamentally limit the TIA noise performance. In this tutorial, we analyze and explore two circuit design approaches to overcome the transimpedance limit. The first approach (Type I) realizes a divide-and-conquer methodology to separate the noise-bandwidth problem and solve them individually. The second approach (Type II) employs a multi-stage stagger-tuned amplifier. Both approaches can overcome the transimpedance limit, forming an effective toolkit for the design of low-noise high-speed TIA for high-sensitivity CMOS optical receivers in current and future applications. [ABSTRACT FROM AUTHOR]

To mitigate the trade-off between gain and bandwidth of CMOS multistage amplifiers, a receiver front-end (FE) that employs a high-gain narrowband transimpedance amplifier (TIA) followed by an equalizing main amplifier (EMA) is proposed. The EMA provides a high-frequency peaking to extend the FE's bandwidth from 25% to 60% of the targeted data rate f b i t . The peaking is realized by adding a pole in the feedback paths of an active feedback-based wideband amplifier. By embedding the peaking in the main amplifier (MA), the front-end meets the sensitivity and gain of conventional equalizer-based receivers with better energy efficiency by eliminating the equalizer stages. Simulated in TSMC 65 nm CMOS technology, the proposed front-end achieves 7.4 dB and 6 dB higher gain at 10 Gb/s and 20 Gb/s, respectively, compared to a conventional front-end that is designed for equal bandwidth and dissipates the same power. The higher gain demonstrates the capability of the proposed technique in breaking the gain-bandwidth trade-off. The higher gain also reduces the power penalty incurred by the decision circuit and improves the sensitivity by 1.5 dB and 2.24 dB at 10 Gb/s and 20 Gb/s, respectively. Simulations also confirm that the proposed FE exhibits a robust performance against process and temperature variations and can support large input currents. [ABSTRACT FROM AUTHOR]

To address the problems of time variations and high interferences in continuous-wave mud pulse telemetry channels, a widely linear recursive least squares decision feedback equalizer with a variable forgetting factor was proposed, a smaller steady-state error was achieved, and the tracking performance of the equalizer in time-varying mud channels was enhanced. Furthermore, employing UD factorization in the recursive algorithm improves the computational stability and ensures robust performance. The simulation results indicate that the proposed equalizer enhances the convergence speed by 46 %. The experimental findings demonstrate that within a 3000 m mud pulse telemetry channel, the proposed equalizer reduces the steady-state mean squared error by 3 to 4 dB and increases the error-free transmission rate from 3 bps to 6 bps. These advancements significantly enhance the performance of continuous wave mud pulse telemetry systems. [ABSTRACT FROM AUTHOR]

High-speed serial interface is a key technology to improve the bandwidth of high-performance interconnection networks, and the channel equalizer is the core component to improve signal integrity. This paper uses the modern digital signal processing (DSP) structure to propose a deep neural network (DNN)-based high-speed channel equalization research method. This method overcomes the inherent shortcoming that the decision speed of the traditional decision feedback equalizer (DFE) is limited by the feedback loop when facing high-speed channels above 50GB in the future. The simulation results show that, compared with the traditional 2-tap DFE architecture with 15-tap FFE, the proposed 3-layer DNN structure has better equalization effect and faster equalization convergence speed, when the PAM4 encoding method is used, the high-speed channel baud rate is 28GB, and the channel loss is 15dB, or the baud rate is 56GB and the channel loss is 30dB. [ABSTRACT FROM AUTHOR]

The artificial neural network (ANN) has been applied to the various fields due to its capability to process complicated nonlinear functions involving a large amount of data. A pseudorandom binary sequence (PRBS) is commonly used to train the ANN since the PRBS is easily generated by using a linear feedback shift register and has a correlation function which is peaked at zero delay but is almost zero at other delays. However, when the PRBS length is not sufficiently long (compared to the input size of the ANN), the ANN trained by the PRBS could suffer from the overfitting where the ANN describes the behavior of the training sequence very well, but does poorly on new data inputs. In this paper, we provide a minimum length of the PRBS required by the ANN to avoid the overfitting for a given input size of the ANN. For this purpose, we analyze the minimum length of the input sequence required to estimate the PRBS pattern through theoretical study. These analyses are confirmed by numerical simulation. The findings of this paper would be used to select the PRBS length for training the ANN.

As 6G research progresses, both visible light communication (VLC) and artificial intelligence (AI) become important components, which makes them appear to converge. Neural networks (NN) as equalizers are gradually occupying an increasingly important position in the research of the physical layer of VLC, especially in nonlinear compensation. In this paper, we will propose three categories of neural network equalizers, including input data reconfiguration NN, network reconfiguration NN and loss function reconfiguration NN. We give the definitions of these three neural networks and their applications in VLC systems. This work allows the reader to have a clearer understanding and future trends of neural networks in visible light communication, especially in terms of equalizers.

In memory devices, such as solid-state drive, multitopology is used for interfaces where multiple memory packages are connected to a controller using a branched transmission line. Impedance mismatching caused by the branches and unwanted reflection from deactivated packages inevitably degrades signal quality, limiting the data rate of the interface. In this article, a simple stub equalizer is proposed to improve the data rate of the memory interface. An open-ended stub is placed between a transmitter and a receiver, and the length, impedance, and location of the stub line are determined to properly cancel the reflection from other branches. Parameters are optimized based on the peak distortion analysis and an exhaustive search considering both read and write modes. The improvements are validated through eye-diagram simulations. [ABSTRACT FROM AUTHOR]

Summary: This article proposes an active balancer, which features bidirectional charge shuttling and adaptive equalization current control, to fast counterbalance the state of charge (SOC) of cells in a lithium‐ion battery (LIB) string. The power circuit consists of certain bidirectional buck‐boost converters to transfer energy among the different cells back and forth. Owing to the characterization of the open‐circuit voltage (OCV) vs SOC in LIB being relatively smooth near the SOC middle range, the SOC‐inspected balance strategy can achieve more precise and efficient equilibrium than the voltage‐based control. Accordingly, a compensated OCV‐based SOC estimation is put forward to take into account the discrepancy of SOC estimation. Besides, the varied‐duty‐cycle (VDC) and curve‐fitting modulation (CFM) methods are devised herein to tackle the problems of slow equalization rate and low balance efficacy, which arise from the diminution in balancing current as the SOC difference between the cells decreases in the later duration of equalization especially. The proposed strategies have taken the battery nonlinear characteristic and circuit parameter nonideality into account and can adaptively modulate the duty cycle with the SOC difference to keep balancing current constant throughout the balancing cycle. Simulated and experimental results are given to demonstrate the feasibility and effectiveness of the same prototype constructed. Compared with the fixed duty cycle and the VDC methods, the proposed CFM has the best balancing efficiency of 81.4%, and the balance time is shortened by 27.1% and 18.6%, respectively. [ABSTRACT FROM AUTHOR]

It is well known that the categories Fuzz of fuzzes and TopFuzz of topological fuzzes are both complete and cocomplete, and some categorical properties of them were introduced by many authors. In this paper, we introduce the structure of equalizers in these categories. In particular, we show that every regular monomorphism is an injective map, but monomorphisms need not be injective, in general.

Multi-rope elevators are widely used in modern buildings. However, problems such as vibration, noise, uneven wear of key components and shortened life caused by the uneven distribution of rope tensions are still unsolved in the elevator industry. In order to balance the different tensions and the axial deformation of each rope, a novel automatic balance equipment for rope-type elevators (NABE-RE) is proposed in this article. Simulations based on the Simscape numerical methodology are used to verify the kinematic rationality of the proposed mechanism. The optimal structural stability of the core components is evaluated through a series of investigations based on the finite element method. Additionally, the manufactured prototypes are put through a series of comparison experiments to evaluate their tension balancing performance. The results show that the unbalance rate of the system is effectively limited to a low level, thus verifying the feasibility of the automatic tension balancing function of the proposed NABE-RE.