Search NASA⌕ Search

SEARCH · Search NASA

Results for “Operational Amplifier”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 775 records · Page 43
All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

On operation and control of CW magnetrons for superconducting accelerators

CW magnetrons, developed for industrial RF heaters, were suggested to feed RF cavities of superconducting accelerators due to higher efficiency and lower cost of RF power than provide traditionally used klystrons, IOTs or solid-state amplifiers. RF amplifiers driven by a master oscillator serve as coherent RF sources. CW magnetrons are regenerative RF auto generators with a huge regenerative gain. This causes regenerative instability with a notable noise when a magnetron operates as an auto generator i.e., with the anode voltage above the threshold of self-excitation. Traditionally, an injection locking by a small signal is used for phase stabilization of magnetrons. In this case CW magnetrons with the injection-locked (coherent) oscillations generate a notable level of noise. This may preclude use of CW magnetrons in this mode in the Superconducting RF (SRF) accelerators. This paper reviews PIC modeling and previously obtained experimental results for the operation and control of CW magnetrons, which led to the development of techniques most suitable for various SRF accelerators using forced RF oscillation of magnetrons, when the magnetron is launched by an injected forcing signal, and regenerative noise is suppressed.

Kazakevich, G. [MUONS Inc., Batavia] (ORCID:000000↗
DOE OSTI2026

MOD-Amp System Design Spring: Spring 2026 – Georgetown University, SYSM–5620

High-energy lasers (HELs) play an important role in both national defense and scientific research. In defense applications, HELs are used for target detection, tracking, and engagement. In research environments, they support studies of extreme physical conditions relevant to fusion energy and plasma science. These systems depend on the amplification of light through stimulated emission of radiation, allowing optical energy to be increased to the levels required for operation. This amplification occurs when light passes through an energized gain medium that receives energy from an external optical or electrical source. To achieve the desired output, laser systems often use multiple amplification stages, including high-gain preamplifiers and lower-gain power or booster amplifiers. At Lawrence Livermore National Laboratory (LLNL) and other national laboratories, many large-aperture laser amplifier systems are aging and rely on system-specific hardware, obsolete technologies, and incomplete documentation. These legacy systems create challenges for maintenance, supportability, and long-term operation. Their lack of standardization also increases the difficulty of sustaining reliable performance over time. As this infrastructure continues to age, the likelihood of unplanned downtime grows, which can negatively affect both national security missions and scientific research programs that depend on dependable HEL capabilities. The purpose of this document is to demonstrate the application of systems engineering fundamentals and design thinking through the development of a laser amplifier case study. The proposed system concept is intended as an academic exercise and not as a finalized engineering design. As a result, the development presented in this document is incomplete and may contain technical assumptions or errors that would require further investigation before any real-world implementation.

42 ENGINEERING↗
DOE OSTI2017

Numerical simulation and dynamical response of a moored hydrokinetic turbine operating in the wake of an upstream turbine for control design

Herein numerical simulation of a downstream hydrokinetic turbine operating in the wake of an upstream turbine for feedback control design is presented. Wake effects from an upstream turbine are quantified in terms of wake velocity and amplified turbulence levels. These effects are integrated in an in-stream hydrokinetic turbine numerical simulation that utilizes a Blade Element Momentum approach with a dynamic wake inflow model. Simulations are carried out on a fixed turbine model to simulate operation in river or tidal channels with conventional foundations, as well as on a compliantly moored turbine model such as those designed to operate in open ocean currents.

13 HYDRO ENERGY↗
DOE OSTI2018

Development of a Regenerative Amplifier for the Coherent electron Cooling Proof of Principle Experiment (CeC-PoP) at RHIC

The commercial laser from NuPhoton that was used for the Coherent-electron-Cooling Proof of Principle (CeC-PoP) experiment in the past runs could not meet the tight specifications needed to demonstrate coherent electron cooling due to nonlinear effects inherent to fiber lasers operating at high pulse peak powers. To overcome these limitations, the Laser design was modified prior to the start of the 2018 RHIC run by introducing an additional amplifier stage that allows to take over the majority of the amplification process from the fiber amplifiers to keep the peak power in the fibers low and avoid the accumulation of nonlinear effects. This approach allows for a reduction of the output power of the NuPhoton laser to about 5% of the nominal power level avoiding the accumulation of nonlinear effect and leaving 6mW of unstable IR seed power (See Figure 2) for a subsequent amplification stage.

43 PARTICLE ACCELERATORS↗
NASA NTRS1977

Charge-coupled differential amplifier

Device solves problem of differential voltage gain in sampled-data metal-oxide semiconductor, producing gain at any frequency compatible with CCD operation, with low noise, low power, good linearity, and high stability.

Hewes, C. R.↗
NASA NTRS2009

MMICs with Radial Probe Transitions to Waveguides

A document presents an update on the innovation reported in Integrated Radial Probe Transition From MMIC to Waveguide (NPO-43957), NASA Tech Briefs Vol. 31, No. 5 (May 2007), page 38. To recapitulate: To enable operation or testing of a monolithic microwave integrated circuit (MMIC), it is necessary to mount the MMIC in a waveguide package that typically has cross-sectional waveguide dimensions of the order of a few hundred microns. A radial probe transition between an MMIC operating at 340 GHz and a waveguide had been designed (but not yet built and tested) to be fabricated as part of a monolithic unit that would include the MMIC. The radial probe could readily be integrated with an MMIC amplifier because the design provided for fabrication of the transition on a substrate of the same material (InP) and thickness (50 m) typical of substrates of MMICs that can operate above 300 GHz. As illustrated in the updated document by drawings, photographs, and plots of test data, the concept has now been realized by designing, fabricating, and testing several MMIC/radial- probe integrated-circuit chips and designing and fabricating a waveguide package to contain each chip.

Samoska, Lorene↗
DOE OSTI2024

Bilevel Nodal Behind-the-meter Solar Disaggregation Under Unexpected Extreme Weather Conditions

As the power grid undergoes significant paradigm shift due to the increasing penetration of renewable generation, the ever-growing installation of behind-the-meter (BTM) solar generation in the power grid also has a significant impact on nodal loads, posing challenges on transmission operators. Furthermore, increasing frequent and severe extreme weather events intertwine with ubiquitous BTM solar generations and have amplified the challenges of accurately model nodal load profiles, especially under the lack of ground-truth information for verification. To tackle these challenges, this paper introduces a bilevel model that utilizes year-long data (e.g., proxy solar, zonal load, and individual node load profiles) to disaggregate metered profiles into actual demand and BTM solar generation at each transmission node. The proxy solar not only scales the BTM solar generation of individual nodes but also create a compensation term for enhancing performance on days with unexpected extreme weather events. The proposed algorithm is validated with real-world PJM Interconnection data during unexpected events like the recent Winter Storm Elliott. For quantitative evaluations, a novel Score error is introduced, which is based on mean percentages and load scales and offers a universal assessment method suitable for all nodes and different data formats (e.g., normalized or raw values).

behind-the-meter solar, load disaggregations, load↗
NASA NTRS1996

Dual-rod Cr: LiSAF oscillator/amplifier for remote sensing applications

A dual rod configuration is used to achieve 16W average power operation from a flashlamp-pumped Cr:LiSAF laser oscillator. A double-pass dual-rod amplifier configuration was used to amplify 141(mu)J pulses from a Q-switched diode-pumped LiSAF oscillator by a factor of (approximately)120. This experiment established a small signal gain of 13.4% per cm at 820 nm. Improved slope efficiency (7.4% electrical-to-light) and pulse repetition frequency (40Hz) were achieved with a single-rod oscillator using improved Cr:LiSAF material.

Early, J. W.↗
NASA NTRS2012

Pre-Flight Testing and Performance of a Ka-Band Software Defined Radio

National Aeronautics and Space Administration (NASA) has developed a space-qualified, reprogrammable, Ka-band Software Defined Radio (SDR) to be utilized as part of an on-orbit, reconfigurable testbed. The testbed will operate on the truss of the International Space Station beginning in late 2012. Three unique SDRs comprise the testbed, and each radio is compliant to the Space Telecommunications Radio System (STRS) Architecture Standard. The testbed provides NASA, industry, other Government agencies, and academic partners the opportunity to develop communications, navigation, and networking applications in the laboratory and space environment, while at the same time advancing SDR technology, reducing risk, and enabling future mission capability. Designed and built by Harris Corporation, the Ka-band SDR is NASA's first space-qualified Ka-band SDR transceiver. The Harris SDR will also mark the first NASA user of the Ka-band capabilities of the Tracking Data and Relay Satellite System (TDRSS) for on-orbit operations. This paper describes the testbed's Ka-band System, including the SDR, travelling wave tube amplifier (TWTA), and antenna system. The reconfigurable aspects of the system enabled by SDR technology are discussed and the Ka-band system performance is presented as measured during extensive pre-flight testing.

Downey, Joseph A.↗
NASA NTRS2017

Development of an Ultra-wide band Receiver for the North America Array

The North America Array (NAA), also known as the next-generation Very Large Array (ngVLA), is a concept for a radio astronomical interferometric array operating in the frequency range 1.2 GHz to 116 GHz and designed to provide substantial improvements in sensitivity, angular resolution, and frequency coverage while reducing operational costs compared to the current Jansky Very Large Array (JVLA). At JPL, we are designing a single receiver package designed to operate across the 8 to 48 GHz frequency range, in contrast to the current JVLA, which covers this frequency range with five receiver packages. Reducing the number of receiving systems required to cover the full frequency range would reduce operating costs. We are developing a prototype integrated feed-receiver package with a system noise temperature that meets the requirements of the ngVLA/NAA primary science programs, with a design that meets the requirement of low long-term operational costs. The receiver package being developed at JPL consists of a feed horn, low-noise amplifier (LNA), and down-converters to analog intermediate frequencies. We report on the status of this receiver package development.

Lazio, Joseph↗
DOE OSTI2023

Comparative Study of Commercial-Scale CO2 Storage Options in Single and Stacked Saline Formations in Managing Reservoir Pressure Buildup

Presentation at American Association of Petroleum Geologists (AAPG) Carbon, Capture, Utilization, and Storage (CCUS) held in Houston, Texas, April 25–27, 2023. The presentation emphasizes the importance of coordination among CO2 storage projects as CCUS deployment needs to be scaled up. The presentation focuses on findings from reservoir simulation studies in which different configurations of injection zones (a single saline formation and a stacked sequence of saline formations) are targeted for CO2 storage to accommodate the amplified storage volume needed while managing reservoir pressure buildup and interference induced by multi-well injection operations.

Wijaya, Nur↗
DOE OSTI2023

Gated truncated readout system

A gated truncated readout system for position sensitive or imaging detectors that improves resolution over traditional readout systems. The readout system includes two or more amplifiers that receive a multichannel output analog data from the detector. Analog gates control circuitry, included in the readout circuit, receives the signals from the amplifiers, determines a fractional value of the sum-integral of the signals, and enables analog gates operation around an area of interest, disabling all other channels where noise dominates the signal value and thereby improving interpolation accuracy of the signals centroid position and the detector resolution. Filtered signals are transmitted to a centroid interpolation signal processing device for computation of the centroid position. As a result disabling all channels where noise dominates the signal value, the gated truncated readout system provides better accuracy improved detector resolution.

Popov, Vladimir↗
DOE OSTI2021

Searching for Dark Matter with Superconducting Qubits

Dark matter is an enduring mystery in our quest to understand the fundamental constituents of our universe. Low mass bosons, such the axion or hidden photon, are compelling dark matter candidates. We leverage their potential interactions with electromagnetic fields, whereby the dark matter (of unknown mass) on rare occasion converts into a single photon, to devise a method of detecting these candidates. Current dark matter searches operating at microwave frequencies use a resonant cavity to coherently accumulate the field sourced by the dark matter and a near standard quantum limited (SQL) linear amplifier to read out the cavity signal. To further increase sensitivity to the dark matter signal and enable future searches, sub-SQL detection techniques are required.In this thesis, I report the development of a novel microwave photon counting technique and a new exclusion limit on hidden photon dark matter. We operate a superconducting qubit to make repeated quantum non-demolition measurements of cavity photons and apply a hidden Markov model analysis to reduce the noise to 15.7 dB below the quantum limit, with overall detector performance limited by a residual background of real photons. With the present device, we perform a hidden photon search and constrain the kinetic mixing angle to less than 1.68 x 10-15 in a band around 6.011 GHz (24.86 micro-eV) with an integration time of 8.33 s. This demonstrated noise reduction technique enables future dark matter searches to be sped up by a factor of 1300. By coupling a qubit to an arbitrary quantum sensor, more general sub-SQL metrology is possible with the techniques presented in this work.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
NASA NTRS1975

Design, construction and evaluation of a 12.045 GHz, 2.0 kW-cw permanent-magnet focused klystron amplifier

An analytical and experimental program to demonstrate the technical feasibility of a lightweight, high-efficiency, 1-2 kW cw, permanent magnet focused klystron operating at 12.0 GHz was described. The design is based on use of a samarium-cobalt permanent magnet for focusing of the electron beam and choice of the most optimum parameters for maximum efficiency. A filter-loaded output circuit is used for the required bandwidth. The design incorporates a collector which is demountable from the tube to facilitate multistage depressed collector experiments, permitting replacement with a NASA-designed axisymmetric, electrostatic collector for linear beam microwave tubes. A further requirement is that the focusing field between the last interaction gap and the collector decay in a prescribed manner referred to as adiabatic expansion.

Nishida, J. M.↗
DOE OSTI2026

Low-stress creep behavior of multiple salt caverns under cyclic operations

Here, the use of multiple salt caverns for large-scale underground hydrogen storage offers a strategic solution to the growing demand for efficient and flexible energy storage, due to the inherent low permeability, high mechanical strength, and self-healing properties of the salt formation. Despite these advantages, the long-term geomechanical response of salt caverns under cyclic injection and withdrawal remains a significant challenge for ensuring operational stability. This mechanistic study highlights the critical role of low-stress creep, also known as pressure solution creep, in governing deformation of salt caverns during cyclic operations. Unlike conventional creep mechanisms that dominate under high-stress conditions, low-stress creep becomes particularly relevant under the moderate stress changes induced by repeated injection and withdrawal, which provides a previously underexplored control on cavern closure. Our three-dimensional computational model integrates the low-stress creep mechanism into the Munson–Dawson creep equation across a spectrum of operational scenarios including variations in cavern pressure cycles, injection-withdrawal frequencies, and caprock mechanical property. The low-stress creep components accelerate the cavern creep closure, which is amplified with shorter cycle frequency and larger pressure difference. Sensitivity analyses capture the complex interactions between multiple caverns and surround formations at the field scale that allows for a quantitative assessment of deformation patterns and closure rates over time and thereby informs the design and operation of sustainable underground hydrogen storage system.

Cyclic operation↗
DOE OSTI2015

Probing the density of states of two-level tunneling systems in silicon oxide films using superconducting lumped element resonators

We have investigated dielectric losses in amorphous silicon oxide (a-SiO) thin films under operating conditions of superconducting qubits (mK temperatures and low microwave powers). For this purpose, we have developed a broadband measurement setup employing multiplexed lumped element resonators using a broadband power combiner and a low-noise amplifier. The measured temperature and power dependences of the dielectric losses are in good agreement with those predicted for atomic two-level tunneling systems (TLS). By measuring the losses at different frequencies, we found that the TLS density of states is energy dependent. This had not been seen previously in loss measurements. These results contribute to a better understanding of decoherence effects in superconducting qubits and suggest a possibility to minimize TLS-related decoherence by reducing the qubit operation frequency.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
NASA NTRS2005

HEMT Frequency Doubler with Output at 300 GHz

An active frequency doubler in the form of an InP-based monolithic microwave integrated circuit (MMIC) containing a high-electron-mobility transistor (HEMT) has been demonstrated in operation at output frequencies in the vicinity of 300 GHz. This is the highestfrequency HEMT doubler reported to date, the next-highest-frequency active HEMT doubler having been previously reported to operate at 180 GHz. While the output power of this frequency doubler is less than that of a typical Schottky diode, this frequency doubler is considered an intermediate product of a continuing effort to realize the potential of active HEMT frequency doublers to operate with conversion efficiencies greater than those of passive diode frequency doublers. An additional incentive for developing active HEMT frequency doublers lies in the fact that they can be integrated with amplifiers, oscillators, and other circuitry on MMIC chips. The circuitry of the doubler MMIC (see Figure 1) features grounded coplanar waveguides. Air bridges and vias are used to make contact with the ground plane. The HEMT is biased for Class-A operation (in which current is conducted throughout each cycle of oscillation), which would ordinarily be better suited to linear amplification than to frequency doubling. Ordinarily, class-B operation (in which current is conducted during about half of each cycle of oscillation) would be more suitable for frequency doubling because of the essential nonlinearity of partial-cycle conduction. The reason for the unusual choice of class A was that computational simulations had shown that in this case, the efficiency in class B would be less than in class A. The input matching circuit of this doubler includes transmission lines that afford a good impedance match at the fundamental frequency, plus an open stub to prevent leakage of the second harmonic through the input terminals. The output circuit was designed to suppress the fundamental while providing a good match for the second harmonic.

Samoska, Lorene↗
DOE OSTI2016

The LCLS variable-energy hard X-ray single-shot spectrometer

The engineering design, implementation, operation and performance of the new variable-energy hard X-ray single-shot spectrometer (HXSSS) for the LCLS free-electron laser (FEL) are reported. The HXSSS system is based on a cylindrically bent Si thin crystal for dispersing the incident polychromatic FEL beam. A spatially resolved detector system consisting of a Ce:YAG X-ray scintillator screen, an optical imaging system and a low-noise pixelated optical camera is used to record the spectrograph. The HXSSS provides single-shot spectrum measurements for users whose experiments depend critically on the knowledge of the self-amplified spontaneous emission FEL spectrum. It also helps accelerator physicists for the continuing studies and optimization of self-seeding, various improved mechanisms for lasing mechanisms, and FEL performance improvements. The designed operating energy range of the HXSSS is from 4 to 20 keV, with the spectral range of order larger than 2% and a spectral resolution of 2 × 10 -5 or better. Those performance goals have all been achieved during the commissioning of the HXSSS.

Rich, David↗