Keyword: Noise

Briefs: Sensors/Data Acquisition
High-Voltage Clock Driver for Photon-Counting CCD Characterization

A document discusses the CCD97 from e2v technologies as it is being evaluated at Goddard Space Flight Center’s Detector Characterization Laboratory (DCL) for possible use in ultra-low background noise space astronomy applications, such as Terrestrial Planet Finder Coronagraph...

Articles: Sensors/Data Acquisition

While charge-coupled device (CCD) and complementary metal-oxide semiconductor (CMOS) sensors perform similar functions — collecting light (photons) and converting those...

Briefs: Electronics & Computers

Column-parallel analog-to-digital converters (ADCs) for imagers involve simultaneous operation of many ADCs. Single-slope ADCs are well adapted to this use because of their simplicity. Each ADC...

Briefs: Information Technology
Bilayer Protograph Codes for Half-Duplex Relay Channels

Direct to Earth return links are limited by the size and power of lander devices. A standard alternative is provided by a two-hops return link: a proximity link (from lander to orbiter relay) and a deep-space link (from orbiter relay to Earth). Although direct to Earth return links are...

Briefs: Physical Sciences
Submillimeter Planetary Atmospheric Chemistry Exploration Sounder

A report describes the Submillimeter Planetary Atmospheric Chemistry Exploration Sounder (SPACES), a highsensitivity laboratory breadboard for a spectrometer targeted at orbital planetary atmospheric analysis. The frequency range is 520 to 590 GHz, with a target noise temperature...

Products: Lighting

Green Watt Power, a division of Calex Mfg. Co. (Concord, CA), recently introduced the GLV-24-150, a constant voltage LED power supply with a universal AC input range, 100 - 277 VAC. The GLV-24-150 has an...

Briefs: Information Technology
Discrete Data Qualification System and Method Comprising Noise Series Fault Detection

A Sensor Data Qualification (SDQ) function has been developed that allows the onboard flight computers on NASA’s launch vehicles to determine the validity of sensor data to ensure that critical safety and operational decisions are not based on faulty sensor...

Briefs: Information Technology
Sequential Probability Ratio Test for Spacecraft Collision Avoidance Maneuver Decisions

A document discusses sequential probability ratio tests that explicitly allow decision-makers to incorporate false alarm and missed detection risks, and are potentially less sensitive to modeling errors than a procedure that relies solely on a probability of...

Briefs: Physical Sciences
Method to Measure Total Noise Temperature of a Wireless Receiver During Operation

A method has been developed to measure the total effective noise power in a GPS receiver, including contributions from the system temperature, the antenna temperature, interference, lossy components, etc. A known level of noise is periodically injected before the...

Briefs: Physical Sciences
Per-Pixel, Dual-Counter Scheme for Optical Communications

Free space optical communications links from deep space are projected to fulfill future NASA communication requirements for 2020 and beyond. Accurate laser-beam pointing is required to achieve high data rates at low power levels. For the highest pointing accuracy, a laser beacon...

Briefs: Information Technology
Display Provides Pilots with Real-Time Sonic-Boom Information

Supersonic aircraft generate shock waves that move outward and extend to the ground. As a cone of pressurized air spreads across the landscape along the flight path, it creates a continuous sonic boom along the flight track. Several factors can influence sonic booms: weight, size, and...

Briefs: Physical Sciences
Data Transfer for Multiple Sensor Networks Over a Broad Temperature Range

At extreme temperatures, cryogenic and over 300 °C, few electronic components are available to support intelligent data transfer over a common, linear combining medium. This innovation allows many sensors to operate on the same wire bus (or on the same airwaves or optical...

Briefs: Information Technology
Mixed Linear/Square-Root Encoded Single-Slope Ramp Provides Low-Noise ADC With High Linearity for Focal Plane Arrays

Single-slope analog-to-digital converters (ADCs) are particularly useful for on-chip digitization in focal plane arrays (FPAs) because of their inherent monotonicity, relative simplicity, and efficiency for column-parallel...

Briefs: Physical Sciences
Single-Photon-Sensitive HgCdTe Avalanche Photodiode Detector

The purpose of this program was to develop single-photon-sensitive shortwavelength infrared (SWIR) and midwavelength infrared (MWIR) avalanche photodiode (APD) receivers based on linear-mode HgCdTe APDs, for application by NASA in light detection and ranging (lidar) sensors....

Briefs: Physical Sciences
Analysis of the Effects of Streamwise Lift Distribution on Sonic Boom Signature

Investigation of sonic boom has been one of the major areas of study in aeronautics due to the benefits a low-boom aircraft has in both civilian and military applications. Current Federal Aviation Administration regulations prohibit supersonic flight over land due to...

Briefs: Electronics & Computers
Amplifier Module for 260-GHz Band Using Quartz Waveguide Transitions

Packaging of MMIC LNA (monolithic microwave integrated circuit low-noise amplifier) chips at frequencies over 200 GHz has always been problematic due to the high loss in the transition between the MMIC chip and the waveguide medium in which the chip will typically be used. In...

Products: Lighting

Gigahertz-Optik (Newburyport, MA) has developed a cost effective measurement system consisting of the BTS256-LED tester and LPS-20-1500 LED power supply with S-BTS256 software to assist with single pulse...

Briefs: Electronics & Computers

A three-frequency millimeter-wave feed horn was developed as part of an advanced component technology task that provides components necessary for higher-frequency radiometers to meet the...

Briefs: Electronics & Computers
Single-Pole Double-Throw MMIC Switches for a Microwave Radiometer

In order to reduce the effect of gain and noise instabilities in the RF chain of a microwave radiometer, a Dicke radiometer topology is often used, as in the case of the proposed surface water and ocean topography (SWOT) radiometer instrument. For this topology, a single-pole...

Briefs: Medical
Improving Balance Function Using Low Levels of Electrical Stimulation of the Balance Organs

Crewmembers returning from long duration space flight face significant challenges due to the microgravity induced inappropriate adaptations in balance/sensorimotor function. The Neuroscience Laboratory at JSC is developing a method based on stochastic...

Application Briefs: Photonics/Optics

Redfern Integrated Optics was awarded a Phase 2 Small Business Innovation Research (SBIR) contract for further development of its single-frequency, narrow- linewidth semiconductor...

Briefs: Information Technology
Pattern Recognition Algorithm for High- Sensitivity Odorant Detection in Unknown Environments

In a realistic odorant detection application environment, the collected sensory data is a mix of unknown chemicals with unknown concentrations and noise. The identification of the odorants among these mixtures is a challenge in data recognition. In...

Briefs: Electronics & Computers
Blocking Losses With a Photon Counter

It was not known how to assess accurately losses in a communications link due to photodetector blocking, a phenomenon wherein a detector is rendered inactive for a short time after the detection of a photon. When used to detect a communications signal, blocking leads to losses relative to an ideal detector,...

Briefs: Physical Sciences
An MSK Radar Waveform

The minimum-shift-keying (MSK) radar waveform is formed by periodically extending a waveform that separately modulates the in-phase and quadraturephase components of the carrier with offset pulse-shaped pseudo noise (PN) sequences. To generate this waveform, a pair of periodic PN sequences is each passed through a...

Briefs: Electronics & Computers
On-Wafer Measurement of a Multi-Stage MMIC Amplifier With 10 dB of Gain at 475 GHz

JPL has measured and calibrated a WR2.2 waveguide wafer probe from GGB Industries in order to allow for measurement of circuits in the 325–500 GHz range. Circuits were measured, and one of the circuits exhibited 10 dB of gain at 475 GHz.

Briefs: Mechanical & Fluid Systems

Previous oil containment booms have an open top that allows natural gas to escape, and have significant oil leakage due to wave action. Also, a subsea pyramid oil trap exists, but cannot move relative to...

Briefs: Physical Sciences
Low-Noise, Large-Area Quad Photoreceivers Based on Low-Capacitance Quad Photodiodes

The Laser Interferometry Space Antenna’s (LISAs) scientific mission to detect gravity waves demands stringent noise limits on the system components, especially the large-area quad photoreceiver front end, for ultra-high-precision (≈10 pm/Hz1/2)...

Briefs: Physical Sciences
Energy-Based Tetrahedron Sensor for High-Temperature, High-Pressure Environments

An acoustic energy-based probe has been developed that incorporates multiple acoustic sensing elements in order to obtain the acoustic pressure and threedimensional acoustic particle velocity. With these quantities, the user can obtain various energy-based...

Briefs: Software
Ring Image Analyzer

Ring Image Analyzer software analyzes images to recognize elliptical patterns. It determines the ellipse parameters (axes ratio, centroid coordinate, tilt angle). The program attempts to recognize elliptical fringes (e.g., Newton Rings) on a photograph and determine their centroid position, the short-to-long-axis ratio, and...