Leakage Compensation Research Articles

Research on layered control of path tracking for unmanned industrial vehicles based on fully hydraulic steering leakage compensation

Industrial vehicles work in complex terrain, the variable centre of mass position, leakage nonlinearity of full hydraulic steering and other issues lead to poor path tracking stability and accuracy. In this paper, an intelligent hierarchical controller for industrial vehicles’ path tracking is designed with full hydraulic steering leakage compensation, including an upper decision layer and a lower execution layer. The upper decision layer observes the pavement-tyre adhesion coefficients through an extended Kalman filter algorithm, and uses the real-time observations of the adhesion coefficients to establish a variable constraint control for the linear time-varying MPC, and thus performs the path tracking control. The lower actuator layer receives the upper layer’s target steering wheel angle output and performs steering operations. Based on the establishment of a mathematical model of full hydraulic steering considering the leakage characteristics, it analyses the leakage disturbance factors and constructs a fuzzy feed-forward steering leakage compensation controller to compensate for the leakage disturbances in real time for path tracking steering. Simulation and experimental results show that the lateral acceleration, sideslip angle, tyre side slip angle and tracking error of intelligent industrial vehicles under different loads and working conditions are improved by more than 32.4%, 35.8%, 40.2% and 45.8% respectively, and the designed hierarchical controller for the path tracking of intelligent industrial vehicles, which considers the compensation of all-hydraulic steering leakage, can effectively improve the path tracking stability and tracking accuracy of intelligent industrial vehicles under different loads and working conditions.

An approach for designing leakage compensated voltage reference circuit

ABSTRACT In this paper, the design of CMOS-based and recyclic folded cascode (RFC)-based voltage reference circuits is presented. Further inherent leakage compensation technique using diode connected MOSFET is introduced, which results in the compensation of high-temperature leakage current and a reduction in consumed power. Moreover, current mirror-induced mismatch and supply dependency reduces. Furthermore, temperature range and power supply rejection ratio (PSRR) improves. Later, comparison between the two configurations, i.e. with and without leakage compensation, has been presented. The minimum value of the achieved temperature coefficient on applying leakage compensation is 4.2 ppm/ºC for the proposed RFC op-amp-based voltage reference circuit with improved temperature range by 40°C. The obtained value of PSRR is −88.2 dB at 10 Hz, −66.8 dB for 1 KHz and −61.6 dB for 1 MHz frequency, with the line sensitivity of 0.031%/V and the variation of 1.69 mV for an entire operating temperature range. All the simulation results are obtained at 0.7 V supply voltage in 180 nm SCL technology.

An N-Type Pseudo-Static eDRAM Macro with Reduced Access Time for High-Speed Processing-in-Memory in Intelligent Sensor Hub Applications

This paper introduces an n-type pseudo-static gain cell (PS-nGC) embedded within dynamic random-access memory (eDRAM) for high-speed processing-in-memory (PIM) applications. The PS-nGC leverages a two-transistor (2T) gain cell and employs an n-type pseudo-static leakage compensation (n-type PSLC) circuit to significantly extend the eDRAM’s retention time. The implementation of a homogeneous NMOS-based 2T gain cell not only reduces write access times but also benefits from a boosted write wordline technique. In a comparison with the previous pseudo-static gain cell design, the proposed PS-nGC exhibits improvements in write and read access times, achieving 3.27 times and 1.81 times reductions in write access time and read access time, respectively. Furthermore, the PS-nGC demonstrates versatility by accommodating a wide supply voltage range, spanning from 0.7 to 1.2 V, while maintaining an operating frequency of 667 MHz. Fabricated using a 28 nm complementary metal oxide semiconductor (CMOS) process, the prototype features an efficient active area, occupying a mere 0.284 µm2 per bitcell for the 4 kb eDRAM macro. Under various operational conditions, including different processes, voltages, and temperatures, the proposed PS-nGC of eDRAM consistently provides speedy and reliable read and write operations.

Development of a non-invasive ventilator for emergency and beyond

The SARS-CoV-2 pandemic led to the development and implementation of emergency ventilators owing to the shortage of ventilators globally. Using invasive ventilators for patient intubation has medical experts concerned about increasing mortality. Early intervention with oxygen and respiratory therapy reduces the need for intubation, increases survival rates, and reduces the stress of critical care ventilators in hospitals. This study explores the capabilities of an easy-to-build and accessible non-invasive ventilator during an emergency and the practical implementation of the ventilator beyond the scope of the emergency. The proposed system consists of a high-pressure turbine integrated with a microcontroller and pressure and flow sensors assembled in a portable design. The non-invasive pressure support system is tested with a single-chamber high-precision lung simulator capable of simulating multiple lung diseases. The system is operated in a spontaneous pressure support mode as a Bi-level Ventilator for varying degrees of pressure level and lung conditions. The proposed study implements two most commonly adapted non-invasive patient circuits, i.e., single passive limb leak circuit and single limb active circuit. Both circuits are tested with and without leakage compensation. Two clinically accepted ventilation modes, i.e., pressure support and volume-assured pressure support ventilation, are presented. The results demonstrate the feasibility of using this type of device for non-invasive respiratory support and highlight the need for further testing to assess its safety and effectiveness in various clinical settings.

Experimental study comparing two different phacoemulsification systems with IOP control during steady-state flow and occlusion break surge events.

To compare peak surge and surge duration time after occlusion break, incision leakage compensation, and passive vacuum for 2 phacoemulsification systems. Carl Zeiss Meditec AG, Oberkochen, Germany. Laboratory study. A spring-eye model was used to test Alcon Centurion Vision and Zeiss Quatera 700 systems. Peak surge and duration was measured after an occlusion break. Quatera tested in flow and vacuum priority modes. Vacuum limits ranged from 300 to 700 mm Hg with intraocular pressure (IOP) set at 30 mm Hg, 55 mm Hg, and 80 mm Hg. IOP vs incision leakage rates of 0 to 15 cc/min and passive vacuum were measured. At 30 mm Hg IOP set point and vacuum limits ranging 300 to 700 mm Hg, the surge duration time after occlusion break ranged 419 to 1740 milliseconds (ms) for Centurion, 284 to 408 ms for Quatera in the flow mode, and 282 to 354 ms for Quatera in the vacuum mode. At 55 mm Hg, values ranged 268 to 1590 ms for Centurion, 258 to 471 ms for Quatera in the flow mode, and 239 to 284 ms for Quatera in the vacuum mode. At 80 mm Hg, values were 243 to 1520 ms for Centurion, 238 to 314 ms for Quatera in the flow mode, and 221 to 279 ms in the vacuum mode. Centurion exhibited slightly less peak surge than the Quatera. At 55 mm Hg: incision leakage rates 0 to 15 cc/min, Quatera held the IOP within ±2 mm Hg of target; Centurion was unable to hold IOP target allowing a 11.7 mm Hg decrease with 32% higher passive vacuum. Quatera demonstrated slightly higher surge peak values and notably shorter surge duration times after occlusion break than Centurion. Quatera demonstrated better incision leakage compensation and lower passive vacuum than Centurion.

A Reliable and High-Speed 6T Compute-SRAM Design With Dual-Split-V DD Assist and Bitline Leakage Compensation

Compute SRAM (CSRAM) can be configured to execute efficient in-memory logic computation and search operations, which is made possible by the multirow activation scheme. Nevertheless, simultaneous multirow activation introduces notorious compute access disturbance in 6T-based CSRAM designs. Existing solutions aim to mitigate the disturbance issue via weakening the access transistor strength, clamping the sensed bitline voltage swing, or substituting with read-decoupled SRAM bitcell designs. However, these techniques all come with significant design overheads of performance degradation in computational read and write accesses and increased layout area. This article presents multiple circuit-level techniques for the design and optimization of a reliable and high-speed 6T-based CSRAM. First, we propose a novel dual-split- <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$V_{\text{DD}}$</tex-math> </inline-formula> (DSV)-assisted scheme for mitigating the compute access disturbance in 6T SRAM and simultaneously improving the computational read access performance. Second, we propose a leakage-compensated asymmetrical differential sense amplifier (LCAD-SA) to further improve the compute access performance. Third, we propose a DSV-assisted columnwise write scheme for accelerating the write performance. The proposed 6T CSRAM was implemented in the 28-nm CMOS, achieving a 1.18-GHz peak operating frequency, which is a 2.36 <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\times$</tex-math> </inline-formula> throughput improvement compared with that of the state-of-the-art CSRAM designs.

A Twice Denoising Autoencoder Framework for Random Seismic Noise Attenuation

Many seismic denoising algorithms are easily trapped in the dilemma of signal leaking and noise remaining. But between the two situations, more complex and common situations happens that both signal leaking and noise remaining exist. We have presented a denoising framework for random seismic noise attenuation to mitigate the dilemma and achieve a better denoising performance. The framework consists of a denoising autoencoder (DAE) and data generator. The DAE attenuates random noise without ground truth and works with a vectoring patching technique to reduce time complexity. In the data generator, local correlation is first developed to nonlinear local correlation to detect and extract the signal leakage with noise components suppressed. Then, the extracted signal leakage is compensated back to the DAE output in a supersaturated way to generate a new record. After that, DAE is used again to suppress the remaining noise in the new record. The supersaturated compensation of the first signal leakage counteracts the signal leakage of the second DAE noise attenuation. Formally, the proposed framework can be implemented like a nonlinear geological inversion by thinking of the data generator as the forward operator. Four 2D/3D synthetic and field examples test the performance of the proposed framework. Experiments demonstrate that the proposed method is effective in random noise attenuation and signal leakage compensation, and thus significantly mitigates the mentioned dilemma.

34.2: Invited Paper: High Image Quality ADS PRO TV Comparable to OLED

ADS display mode has many advantages, especially wide viewing angle, and has been widely used in various LCD products. In this paper, based on the upgraded ADS PRO technology, we adopt high CR negative liquid crystal, low reflection surface materials and process, oblique angle light leakage compensation film, spectrum matching optimize of BLU and RGB resin, and combined with mini LED backlight. Based on these methods, we achieve the native CR &gt;3000:1, extreme black state with reflectivity &lt; 1.5%, high ambient color contrast, no color shift angle of &gt; ±60 °, and DCI P3 99% high color gamut. Its ultimate picture quality can be equivalent to OLED.

Pseudo-Static Gain Cell of Embedded DRAM for Processing-in-Memory in Intelligent IoT Sensor Nodes.

This paper presents a pseudo-static gain cell (PS-GC) with extended retention time for an embedded dynamic random-access memory (eDRAM) macro for analog processing-in-memory (PIM). The proposed eDRAM cell consists of a two-transistor (2T) gain cell with a pseudo-static leakage compensation that maintains stored data without charge loss issue. Hence, the PS-GC can offer unlimited retention time in the same manner as static RAM (SRAM). Due to the extended retention time, bulky capacitors in conventional eDRAM are no longer needed, thereby, improving the area efficiency of eDRAM-based analog PIMs. The active leakage compensation of the PS-GC can effectively hold stored data even in a deep-submicron process that show significant leakage current. Therefore, the PS-GC can accelerate write-access time and read-access time without concern of increased leakage current. The proposed gain cell and its 64 × 64 eDRAM macro were implemented in a 28 nm CMOS process. The bitcell of the proposed gain cell has 0.79- and 0.58-times the area of those of 6T SRAM and 8T STAM, respectively. The post-layout simulation results demonstrate that the eDRAM maintains the pseudo-static operation with unlimited retention time successfully under wide range variations of process, voltage and temperature. At the operating frequency of 667 MHz, the eDRAM macro achieved an operating voltage range from 0.9 to 1.2 V and operating temperature range from −25 to 85 °C regardless of the process variation. The post-layout simulated write-access time and read-access time were below 0.3 ns at an operating temperature of 85 °C. The PS-GC consumes a static power of 2.2 nW/bit at an operating temperature of 25 °C.

Fuzzy Compensation and Load Disturbance Adaptive Control Strategy for Electro-Hydraulic Servo Pump Control System

Aiming at the high-precision position control of electro-hydraulic servo pump control system, a compensation control algorithm based on fuzzy control theory is proposed based on the classical PID control algorithm for the control of factors such as oil compression and system leakage. Firstly, a mathematical model of the system was established, and online identification of load disturbance was carried out. Then, oil compression and system leakage compensation controllers were established, and the position error caused by the load disturbance was compensated based on fuzzy control rules. Finally, the position control effect was verified using an experimental platform. The results show that the load disturbance compensation control strategy can significantly reduce the influence of load disturbance of the system. The steady-state accuracy of the system reached ±0.01 mm, which significantly enhanced the anti-disturbance ability of the system.

The elimination of stressed induced light leakage for in-plane-switching LCD

As the mainstream display mode of LCD, IPS is overwhelmingly used in many fields of flat displays. However, due to the stress sensitivity of glass, the stressed light leakage is a bottleneck for achieving perfect dark state performance. The conventional scheme of using a compensation polarizer outside the cell has no effect on this light leakage. Although many studies have been conducted to overcome this limitation, the proposed methods have limited effects. Our research team has proposed a novel light leakage compensation mechanism by introducing a positive A plate that is sandwiched between the glass and the LC layer, therefore the light leakage which is caused by the combined effect of the phase retardations from the stressed glasses and the LC layer can be eliminated. In addition to theoretically analyzing the compensation principles of the novel light leakage compensation mechanism, we also use the developed positive A material to prepare light leakage compensation demos. And then the electric-optical characteristics and light leakage compensation effects of the demos are evaluated. While maintaining excellent optical and electrical characteristics, this technology effectively solves the problem of stressed light leakage of glass-based IPS, improves the dark-state image quality, and breaks the application of IPS in products such as curve products.

Mitigation of Leakage and Stationary Clutters in Short-Range FMCW Radar With Hybrid Analog and Digital Compensation Technique

In short-range sensing, the frequency-modulated continuous-wave (FMCW) radar is subject to the leakage between the transmitter (Tx) and the receiver (Rx) and the stationary clutter reflections, which are difficult to deal with due to the proximity to the target. The proximity ghost image may not only interfere with the target but also pose limitations on the radar performance, such as the degradation of the signal-to-noise ratio (SNR). This article proposes a novel hybrid analog and digital compensation techniques, which mitigates the leakage and the stationary clutters by compensating with the prestored anti-interference signals in both analog and digital domains at the intermediate-frequency (IF) stage. A novel modulation signal-based synchronization (MBS) technique is developed to align the real-time IF signal with the anti-interference signal during the compensation process. By significantly suppressing both the Tx-Rx leakage and the stationary clutters, the proposed technique greatly improves the signal-to-interference ratio (SIR) of the IF beat signals and makes possible the detection of targets with weak reflections. Moreover, the analog compensation enables the full use of the dynamic range of the analog-to-digital converter (ADC), which will reduce the impact of quantization noise and, thus, improve the SNR. Experiments have been carried out to validate the performance of the proposed technique in leakage compensation, weak target detection, stationary clutter compensation, and gesture sensing. The experimental results show that the SIR and the SNR have been improved by around 38 and 10 dB, respectively.

Evaluation of Pulsed Septum Leakage Fields and Compensation for the Advanced Photon Source Upgrade

Evaluation of Pulsed Septum Leakage Fields and Compensation for the Advanced Photon Source Upgrade

Functioning of EPR Automatic Frequency Control in the Presence of the Circulator\u2019s Spurious Leakage

This article presents an analysis of spurious signals’ influence on automatic frequency control (AFC) in EPR spectrometers. The primary source of spurious signals is leakage across the circulator in the microwave bridge. Additionally, the signals reflected from connectors in the line between the circulator and the resonator modify that signal. Spurious signals may degrade the performance of AFC, significantly offsetting lock points from the center frequency of the resonator. The offset’s size depends on the parameters of the resonator and the amount of the circulator isolation. It can be minimized by the appropriate use of a phase shifter located in the line between the circulator and the resonator. Another way to avoid these problems is to introduce a leakage compensation arm to the microwave bridge.

Monostatic and Bistatic G-Band BiCMOS Radar Transceivers With On-Chip Antennas and Tunable TX-to-RX Leakage Cancellation

This article presents $G$ -band monostatic and bistatic radar transceivers (TRX) incorporating on-chip antennas for short-range high-precision applications. The circuits were fabricated using a silicon–germanium (SiGe) BiCMOS technology offering heterojunction bipolar transistors (HBTs) with $\bf {f}_{\mathbf {T}}/\bf {f}_{\mathbf {MAX}}$ of 300/500 GHz. The monostatic TRX implements a tunable leakage canceller (LC) for enhanced transmitter (TX)-to-receiver (RX) leakage compensation and hence improved detectability of weakly reflecting near targets. A standalone monostatic TRX characterized at on-wafer level achieves 4-dBm maximum output power ( $\bf {P}_{\mathbf {TX}}$ ) and 19-dB peak conversion gain ( $\bf {G}_{\mathbf {RX}}$ ) with 3-dB bandwidths of 18 and 17GHz for the TX and the RX, respectively. The bistatic version reaches $\bf {P}_{\mathbf {TX}}$ of 13 dBm and $\bf {G}_{\mathbf {RX}}$ of 24 dB expanding the 3-dB bandwidths to 32 and 34 GHz for the TX and RX, respectively. A double-folded dipole antenna providing 5-dBi gain at 170 GHz was implemented using localized backside etching (LBE) and integrated with the transceivers. A frequency-modulated continuous-wave (FMCW) radar demonstrator incorporating an external phase-locked loop (PLL) was built to evaluate both TRXs and tunable leakage cancellation feature available in the monostatic variant. The maximum equivalent isotropic radiated power ( $\bf {EIRP}$ ), including on-chip antennas, is 8 and 18 dBm for the monostatic and bistatic TRX, respectively. The radars support sweep bandwidth up to 20 GHz reaching 2.1 cm spatial resolution. For a target at 1 m distance the measured ranging precision is $105~\mu \text{m}$ and $13~\mu \text{m}$ for monostatic and bistatic TRX, accordingly. Activation of leakage cancellation effectively suppresses close-in noise and extends the minimum detectable range remarkably.

Financial precautions, carbon dioxide leakage, and the European Directive 2009/31/EC on carbon capture and storage (CCS)

The phenomenon of anthropogenic climate change has been identified as a threat multiplier for many human-related concerns. Carbon capture and storage (CCS) can, in combination with several other mitigation technologies, alleviate global warming by reducing carbon dioxide (CO2) emissions. Reducing climate change-related risks via CCS creates another risk, smaller in extent: the risk that some of the stored CO2 leaks out of the storage complex. This article reviews European legislation and evaluates how one of its objectives, that private liabilities of CCS-related leakage risks are not socialized, is ensured. Slight modifications of European legislation are suggested in order to prevent an indefinite liability of CCS operators in case a storage complex turns out to be unexpectedly and unavoidably prone to CO2 leakages. Official German and Hungarian financial precaution specifications are contrasted and related to this article’s finding that the state budget is sufficiently hedged against the expected value of climate-related leakage compensation costs of poorly managed storage complexes if 3 to 6% of a CCS operator’s emission-related revenues are diverted into a financial precaution fund.

An Alternative Circuitry for a Transformer-Coupled LC Inversion Generator

A new alternative circuitry for the transformer-coupled LC inversion generator (TCLCG) is presented. In principle, a TCLCG consists of one in-phase 1:1 transformer and two capacitors per elementary stage. First, the two capacitors will be charged via the primary winding of the transformer in opposite polarity. Afterward, voltage multiplication is being achieved by a closing switch which shortcuts the two capacitors. The odd-numbered capacitor discharges slowly through the primary inductance of the transformer, whereas the even-numbered capacitor discharges fastly through only the leakage inductance of the transformer and, thus, inverts. However, one of the main drawbacks of the classical “textbook” TCLCG circuitry is caused by the fact that connection of the transformers of the higher generator stages is done through the transformers of the lower stages. Consequently, compensation techniques must be applied, i.e., adjustment of the even capacitors and/or transformer inductance values, in order to ensure effective voltage multiplication by means of constructive superposition of each stage. This limits the maximum practical generator stage number and rise time. In the alternative TCLCG circuit principle, the connections to the primary and secondary inputs of the transformers of the higher stages are being done directly from the closing switch. Now, the transformers are in parallel to each other, not in series as in the classical TCLCG circuitry. As a result, the even-numbered capacitors see the same leakage inductance and compensation techniques are no longer necessary. The first experimental verification was done by direct comparison of the classical circuitry and alternative circuitry for two compact two-stage TCLCGs with identical transformers and capacitances. The results showed that the alternative circuitry leads to a fast generator rise time of 25 ns, about 38% faster than the classical circuitry, while still reaching the same generator efficiency of 67%. Additionally, rise time proved to stay constant at 25 ns even if adding the third stage to the TCLCG with the new alternative geometry. This version was still 46% faster than an optimized classical three-stage TCLCG using the asymmetric compensation method.

Experimental Investigation and Theoretical Modelling of a High-Pressure Pneumatic Catapult Considering Dynamic Leakage and Convection.

A high-pressure pneumatic catapult works under extreme boundaries such as high-pressure and rapid change of pressure and temperature, with the features of nonlinearity and gas-solid convection. In the thermodynamics processes, the pressure is much larger than the critical pressure, and the compressibility factor can deviate from the Zeno line significantly. Therefore, the pneumatic performance and thermo-physical properties need to be described with the real gas hypothesis instead of the ideal gas one. It is found that the analytical results based on the ideal gas model overestimate the performance of the catapult, in comparison to the test data. To obtain a theoretical model with dynamic leakage compensation, leakage tests are carried out, and the relationship among the leakage rate, pressure and stroke is fitted. The compressibility factor library of the equation of state for compressed air is established and evaluated by referring it to the Nelson-Obert generalized compressibility charts. Based on the Peng–Robinson equation, a theoretical model of the high-pressure pneumatic catapult is developed, in which the effects of dynamic leakage and the forced convective heat transfer between the gas and the metal wall are taken into account. The results from the theoretical model are consistent with the data from ejection tests. This research presents an approach to study the performance of a high-pressure pneumatic catapult with high precision.

Gate leakage compensation technique for self‐cascode based voltage references

This communication describes a gate leakage compensation technique to ensure wide-temperature operation and wide-supply regulation of traditional self-cascode based voltage references in deep nanometre nodes ( ). Extensive simulations in 28 nm ultra-thin buried oxide fully depleted silicon-on-insulator CMOS process show that the proposed 4-transistor topology can operate down to 0.2 V, generating a reference voltage of 98.2 mV with mean and best temperature coefficients of 68.9 and , respectively, from to .

Low-Complexity Time-Domain Averaging-Based DAC Clock Tone Leakage Compensation for Short-Reach PAM4 Transmission

High sampling-rate digital-to-analog converters (DAC) are usually applied in optical fiber communication systems for the signal generation with advanced modulation formats such as four-level pulse amplitude modulation (PAM4). There exist various imperfections for high sampling-rate DACs. Clock tone leakage (CTL) is one of the imperfections and may seriously degrade the bit error rate (BER) performance, especially for single-carrier transmission systems. In this paper, we study a low-complexity time-domain averaging (TDA) based CTL compensation (TDA-CTLC) method for short-reach PAM4 transmission. By numerical simulation, we investigate the impacts of chromatic dispersion, CTL interference-to-signal power ratio (ISPR), and vertical resolution of the analog-to-digital converter on the BER performance. The results exhibit that the TDA-CTLC enabled PAM4 transmission system in the presence of a wide range of ISPR has a similar BER performance with the one without CTL interference. Moreover, we experimentally evaluate the compensation performance of the TDA-CTLC in a directly-modulated laser-based short-reach PAM4 transmission system. Up to −4 dB ISPR can be compensated with a slight BER performance degradation due to nonlinear distortions.