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Krainak, Michael A.

Publications and source records attributed to Krainak, Michael A..

At least 55 records · Page 3
All sourcesNASA NTRSDOE OSTI
NASA NTRS2008

Oxygen Spectroscopy Laser Sounding Instrument for Remote Sensing of Atmospheric Pressure

We report on the progress of an Oxygen spectroscopy laser sounding instrument designed as a calibration channel for a carbon dioxide (CO2) laser sounding instrument. We have developed a pulsed, frequency-doubled, fiber laser transmitter for use in an oxygen instrument. The instrument concept uses the pressure broadening of spectroscopic lines of the diatomic oxygen A-band to deduce atmospheric pressure. There are many uses for this measurement but we are developing it primarily to make a measurement of the dry mixing ratio of CO2. The CO2 measurement can be affected by changes in atmospheric properties such as humidity, temperature and pressure. To remove these variances requires measuring a stable, well-mixed gas like Oxygen. We will report on the basic theory behind the instrument, measurements made at a test site at Goddard, review the current state of the instrument technologies and the necessary steps to bring them to space readiness, and review the current state of the instrument development.

Stephen Mark A.↗
NASA NTRS2008

Direct-detection Free-space Laser Transceiver Test-bed

NASA Goddard Space Flight Center is developing a direct-detection free-space laser communications transceiver test bed. The laser transmitter is a master-oscillator power amplifier (MOPA) configuration using a 1060 nm wavelength laser-diode with a two-stage multi-watt Ytterbium fiber amplifier. Dual Mach-Zehnder electro-optic modulators provide an extinction ratio greater than 40 dB. The MOPA design delivered 10-W average power with low-duty-cycle PPM waveforms and achieved 1.7 kW peak power. We use pulse-position modulation format with a pseudo-noise code header to assist clock recovery and frame boundary identification. We are examining the use of low-density-parity-check (LDPC) codes for forward error correction. Our receiver uses an InGaAsP 1 mm diameter photocathode hybrid photomultiplier tube (HPMT) cooled with a thermo-electric cooler. The HPMT has 25% single-photon detection efficiency at 1064 nm wavelength with a dark count rate of 60,000/s at -22 degrees Celsius and a single-photon impulse response of 0.9 ns. We report on progress toward demonstrating a combined laser communications and ranging field experiment.

Krainak, Michael A.↗
NASA NTRS2007

InGaAsP Avalanche Photodetectors for Non-Gated 1.06 micrometer Photon-Counting Receivers

The efficient detection of single photons at 1.06 micron is of considerable interest for lidar/ladar systems designed for remote sensing an d ranging as well as for free-space optical transmission in photon-st arved applications. However, silicon-based single photon avalanche diodes (SPADs) used at shorter wavelengths have very low single photon d etection efficiency (approximately 1 - 2%) at 1.06 micron, and InP/In GaAs SPADs designed for telecommunications wavelengths near 1.5 micro n exhibit high dark count rates that generally inhibit non-gated (free-running) operation. To bridge this "single photon detection gap" for wavelengths just beyond 1 micron, we have developed high performance , large area (80 - 200 micron diameter) InP-based InGaAsP quaternary absorber SPADs optimized for operation at 1.06 micron and based on a highly reliable planar geometry avalanche photodiode structure. We wil l show that dark count rates are sufficiently low to allow for non-ga ted operation while achieving detection efficiencies far surpassing t hose found for Si SPADs. At a detection efficiency of 10%, 80 micron diameter devices exhibit dark count rates below 1000 Hz and count rate s of at least 3 MHz when operated at -40 C. Significantly higher dete ction efficiencies (30 - 50%) are achievable with acceptable tradeoff s in dark count rate. In this paper, we will also discuss performance modeling for these devices and compare their behavior with longer wav elength InP-based InGaAs ternary absorber SPADs fabricated on a relat ed device design platform.

Itzler, Mark A.↗
NASA NTRS2007

Near-infrared Single-photon-counting Detectors for Free-space Laser Receivers

We compare several photon-counting detector technologies for use as near-infrared timeresolved laser receivers in science instrument, communication and navigation systems. The key technologies are InGaAs(P) photocathode hybrid photomultiplier tubes and InGaAs(P) and HgCdTe avalanche photodiodes. We discuss recent experimental results and application.

Krainak, Michael A.↗
NASA NTRS2007

NASA Goddard's Application of Lasers in Space

Researchers at NASA Goddard have been applying lasers for space measurements for over 4 decades, starting with satellite laser ranging in the mid 1960s. This talk will briefly review the history of Goddard's application to lasers to the scientific exploration of space, provide an overview of its ongoing laser-related programs, and give some possibilities for the future.

Abshire, James B.↗
NASA NTRS2005

Fiber lasers and amplifiers for science and exploration at NASA Goddard Space Flight Center

We discuss present and near-term uses for high-power fiber lasers and amplifiers for NASA- specific applications including planetary topography and atmospheric spectroscopy. Fiber lasers and amplifiers offer numerous advantages for both near-term and future deployment of instruments on exploration and science remote sensing orbiting satellites. Ground-based and airborne systems provide an evolutionary path to space and a means for calibration and verification of space-borne systems. We present experimental progress on both the fiber transmitters and instrument prototypes for ongoing development efforts. These near-infrared instruments are laser sounders and lidars for measuring atmospheric carbon dioxide, oxygen, water vapor and methane and a pseudo-noise (PN) code laser ranging system. The associated fiber transmitters include high-power erbium, ytterbium, neodymium and Raman fiber amplifiers. In addition, we will discuss near-term fiber laser and amplifier requirements and programs for NASA free space optical communications, planetary topography and atmospheric spectroscopy.

Krainak, Michael A.↗
NASA NTRS2005

Near-Infrared Single-Photon-Counting Detectors for Laser Instrument Applications at NASA Goddard Space Flight Center

We discuss single-photon-counting detectors requirements for NASA remote sensing and communications systems. We present experimental measurements on several different near-infrared single-photon-counting detectors including InGaAs/InP and InGaAs/InAlAs avalanche photodiodes (APD), an InGaAsP photocathode hybrid photomultiplier (PMT) and an InGaAs photomultiplier. We present the experimental performance of prototype instruments for laser ranging, communication, and trace-gas detection that use these detectors.

Krainak, Michael A.↗
NASA NTRS2004

Laser Sounder Approach for Measuring Atmospheric CO2 from Orbit

We report on an active remote sensing approach using an erbium fiber amplifier based transmitter for atmospheric CO2 measurements in an overtone band near 1.57 microns and initial horizontal path measurements to less than 1% precision.

Krainak, Michael A.↗
NASA NTRS2004

Photon Counting Detectors for the 1.0 - 2.0 Micron Wavelength Range

We describe results on the development of greater than 200 micron diameter, single-element photon-counting detectors for the 1-2 micron wavelength range. The technical goals include quantum efficiency in the range 10-70%; detector diameter greater than 200 microns; dark count rate below 100 kilo counts-per-second (cps), and maximum count rate above 10 Mcps.

Krainak, Michael A.↗
NASA NTRS2003

Tunable Solid-Etalon Filter for the ICESat/GLAS 532 nm Channel Lidar Receiver

The Geoscience Laser Altimeter System (GLAS) was launched into Earth orbit on board the Ice, Cloud and land Elevation Satellite (ICESat) on January 12, 2003. GLAS is a laser altimeter designed to measure ice-sheet topography and associated temporal changes, as well as cloud and atmospheric properties. Each (of the three identical) GLAS lasers is a diode pumped, Q-switched Nd:YAG laser with energy levels of 75 mJ (1064 nm) and 35 mJ (532 nm). The infrared pulse is used for both surface altimetry and atmospheric measurements while the green pulse is used primarily for atmospheric measurements. The receiver uses a 1 meter diameter telescope. We report on the tunable solid-etalon filter used in the ICESat/GLAS 532 nm channel lidar receiver.

Krainak, Michael A.↗
NASA NTRS2002

A Ground-Based Profiling Differential Absorption LIDAR System for Measuring CO2 in the Planetary Boundary Layer

Ground-based LIDAR observations can potentially provide continuous profiles of CO2 through the planetary boundary layer and into the free troposphere. We will present initial atmospheric measurements from a prototype system that is based on components developed by the telecommunications industry. Preliminary measurements and instrument performance calculations indicate that an optimized differential absorption LIDAR (DIAL) system will be capable of providing continuous hourly averaged profiles with 250m vertical resolution and better than 1 ppm precision at 1 km. Precision increases (decreases) at lower (higher) altitudes and is directly proportional to altitude resolution and acquisition time. Thus, precision can be improved if temporal or vertical resolution is sacrificed. Our approach measures absorption by CO2 of pulsed laser light at 1.6 microns backscattered from atmospheric aerosols. Aerosol concentrations in the planetary boundary layer are relatively high and are expected to provide adequate signal returns for the desired resolution. The long-term goal of the project is to develop a rugged, autonomous system using only commercially available components that can be replicated inexpensively for deployment in a monitoring network.

Andrews, Arlyn E.↗
NASA NTRS1999

Stable CW Single-Frequency Operation of Fabry-Perot Laser Diodes by Self-Injection Phase Locking

Previously, single-frequency semiconductor laser operation using fiber Bragg gratings has been achieved by two methods: 1) use of the FBG as the output coupler for an anti-reflection-coated semiconductor gain element'; 2) pulsed operation of a gain-switched Fabry-Perot laser diode with FBG-optical and RF-electrical feedback. Here, we demonstrate CW single frequency operation from a non-AR coated Fabry-Perot laser diode using only FBG optical feedback. We coupled a nominal 935 run-wavelength Fabry-Perot laser diode to an ultra narrow band (18 pm) FBG. When tuned by varying its temperature, the laser wavelength is pulled toward the centerline of the Bragg grating, and the spectrum of the laser output is seen to fall into three discrete stability regimes as measured by the side-mode suppression ratio.

Duerksen, Gary L.↗