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One of the main approaches for distance estimation is the received signal strength (RSS) based techniques. Their drawbacks include the requirement of accurate knowledge of the transmit power and antenna gains. Also, the traditional RSS-based techniques do not take into account the molecular absorption that occurs at terahertz frequencies. In this paper, we propose a distance estimation method for the line-of-sight case that actually takes advantage of the molecular absorption. The proposed method measures the RSS at two frequencies and does not require known transmit powers and antenna gains, which are assumed to be almost the same at the two frequencies. Therefore, the two frequencies have to be relatively close to each other. The proposed distance estimation method calculates the difference of the received powers (in the dB domain) at the two frequencies and finds the link distance based on it and the humidity level.

Hydrogen has become a strong candidate to be a future energy storage medium but there are technological challenges both in its production and storage. For storage, a search for lightweight, abundant and non-toxic materials is on the way. An abundant natural material such as wood cellulose would make an ideal storage medium from a sustainability perspective. Here, using a combination of static DFT calculations and ab initio molecular dynamics simulations at different temperatures, it is shown that wood cellulose has the ability to uptake H-2 via a physisorption mechanism based on dispersion interactions of the van der Waals type involving the O-atoms of the D-glucose rings. The absorption causes little to no disturbances on the cellulose structure and H-2 is highly mobile in the material. At an external pressure of H-2(g) of 0.09 atm and T = 25 degrees C, cellulose has a theoretical gravimetric density of hydrogen storage of approximate to 1%., QC 20200605

Impulse response is vital for wireless communication analysis and modeling. This paper considers the impulse response of the terahertz band (THz band: 0.1–10 THz) for short range (1–100 cm) wireless communication. Earlier works derived the impulse response from transmittance by assuming a linear phase, which corresponds to a line-of-sight (LoS) propagation delay to a receiver. However, the linear phase leads to a symmetric impulse response before and after the LoS propagation delay. Physically, it is impossible for a signal to arrive before the LoS propagation delay since this violates causality. To address this issue, this study derives a phase function leading to an impulse response that satisfies causality. The validity of the derived model is verified with experimental THz band measurements (up to 2 THz), which show excellent agreement with the results predicted by the theory. From the impulse response, coherence bandwidth is found for both the entire THz band and its subbands. The results show significant variations in the coherence bandwidth as a function of the center frequency. Knowledge of these variations supports selection of the proper center frequency for wireless communications in the THz band.

Optical frequency comb spectroscopy (OFCS) combines two previously exclusive features, i.e., wide optical bandwidth and high spectral resolution, enabling precise measurements of entire molecular bands and simultaneous monitoring of multiple gas species in a short measurement time. Moreover, the equidistant mode structure of frequency combs enables efficient coupling of the comb power to enhancement resonant cavities, yielding high detection sensitivities. Different broadband detection methods have been developed to exploit the full potential of frequency combs in spectroscopy, based either on Fourier transform spectroscopy or on dispersive elements.There have been two main aims of the research presented in this thesis. The first has been to improve the performance of mechanical Fourier transform spectrometers (FTS) based on frequency combs in terms of sensitivity, resolution and spectral coverage. In pursuit of this aim, we have developed a new spectroscopic technique, so-called noise-immune cavity-enhanced optical frequency comb spectroscopy (NICE-OFCS), and achieved a shot-noise-limited sensitivity and low ppb (parts-per-billion, 10−9) CO2 concentration detection limit in the near-infrared range using commercially available components. We have also realized a novel method for acquisition and analysis of comb-based FTS spectra, a so-called sub-nominal resolution method, which provides ultra-high spectral resolution and frequency accuracy (both in kHz range, limited only by the stability of the comb) over the broadband spectral range of the frequency comb. Finally, we have developed an optical parametric oscillator generating a frequency comb in the mid-infrared range, where the strongest ro-vibrational molecular absorption lines reside. Using this mid-infrared comb and an FTS, we have demonstrated, for the first time, comb spectroscopy above 5 μm, measured broadband spectra of several species and reached low ppb detection limits for CH4, NO and CO in 1 s.The secon, Optisk frekvenskamspektroskopi (OFCS) kombinerar två tidigare icke förenliga egenskaper, dvs. ett brett optiskt frekvensområde med en hög spektral upplösning, vilket möjliggör noggranna mätningar av hela molekylära absorptionsband och detektion av flera gaser samtidigt med en kort mättid. Eftersom frekvenskammar har en regelbunden struktur med jämnt separerade laser moder kan man effektivt koppla kammen till en optisk kavitet och därmed möjliggöra frekvenskamsdetektion med hög känslighet. Olika metoder har utvecklats för att utnyttja frekvenskammarnas fulla potential för spektroskopi, baserad på antingen Fouriertransform-spektroskopi eller dispersiva element.Forskningen som presenteras i denna avhandling har haft två huvudmål. Det första har varit att förbättra prestandan hos mekaniska Fourier-transformspektrometrar (FTS) baserat på frekvenskammar med avseende på känslighet, upplösning och spektral täckning. I strävan efter detta har vi utvecklat en ny spektroskopisk teknik, benämnd brusimmun kavitetsförstärkt optisk frekvenskamspektroskopi (NICE-OFCS), och uppnått en hagelbrusbegränsad känslighet och detektionsgränser ner till låga ppb koncentrationer (miljarddelar, 10−9) för CO2 i det när-infraröda frekvensområdet enbart med användning av kommersiellt tillgängliga komponenter. Vi har också utvecklat en ny metod för insamling och analys av kambaserade FTS-spektra, som betecknas ha sub-nominell upplösning. Metoden gör det möjligt att uppnå ultrahög spektral upplösning och hög frekvensnoggrannhet (båda i kHz-området, endast begränsad av kammens stabilitet) över kammens hela frekvensområde. Slutligen har vi utvecklat en optisk parametrisk oscillator som genererar en frekvenskam i det mid-infraröda frekvensområdet, där de starkaste rotations-vibrationsmolekylära absorptionslinjerna finns. Med hjälp av denna kam och en FTS har vi för första gången demonstrerat frekvenskamspektroskopi över 5 μm. Vi har detekterat bredbandsspektra av flera molekylära gaser och har, för mä

Optical frequency comb spectroscopy (OFCS) combines two previously exclusive features, i.e., wide optical bandwidth and high spectral resolution, enabling precise measurements of entire molecular bands and simultaneous monitoring of multiple gas species in a short measurement time. Moreover, the equidistant mode structure of frequency combs enables efficient coupling of the comb power to enhancement resonant cavities, yielding high detection sensitivities. Different broadband detection methods have been developed to exploit the full potential of frequency combs in spectroscopy, based either on Fourier transform spectroscopy or on dispersive elements.There have been two main aims of the research presented in this thesis. The first has been to improve the performance of mechanical Fourier transform spectrometers (FTS) based on frequency combs in terms of sensitivity, resolution and spectral coverage. In pursuit of this aim, we have developed a new spectroscopic technique, so-called noise-immune cavity-enhanced optical frequency comb spectroscopy (NICE-OFCS), and achieved a shot-noise-limited sensitivity and low ppb (parts-per-billion, 10−9) CO2 concentration detection limit in the near-infrared range using commercially available components. We have also realized a novel method for acquisition and analysis of comb-based FTS spectra, a so-called sub-nominal resolution method, which provides ultra-high spectral resolution and frequency accuracy (both in kHz range, limited only by the stability of the comb) over the broadband spectral range of the frequency comb. Finally, we have developed an optical parametric oscillator generating a frequency comb in the mid-infrared range, where the strongest ro-vibrational molecular absorption lines reside. Using this mid-infrared comb and an FTS, we have demonstrated, for the first time, comb spectroscopy above 5 μm, measured broadband spectra of several species and reached low ppb detection limits for CH4, NO and CO in 1 s.The secon, Optisk frekvenskamspektroskopi (OFCS) kombinerar två tidigare icke förenliga egenskaper, dvs. ett brett optiskt frekvensområde med en hög spektral upplösning, vilket möjliggör noggranna mätningar av hela molekylära absorptionsband och detektion av flera gaser samtidigt med en kort mättid. Eftersom frekvenskammar har en regelbunden struktur med jämnt separerade laser moder kan man effektivt koppla kammen till en optisk kavitet och därmed möjliggöra frekvenskamsdetektion med hög känslighet. Olika metoder har utvecklats för att utnyttja frekvenskammarnas fulla potential för spektroskopi, baserad på antingen Fouriertransform-spektroskopi eller dispersiva element.Forskningen som presenteras i denna avhandling har haft två huvudmål. Det första har varit att förbättra prestandan hos mekaniska Fourier-transformspektrometrar (FTS) baserat på frekvenskammar med avseende på känslighet, upplösning och spektral täckning. I strävan efter detta har vi utvecklat en ny spektroskopisk teknik, benämnd brusimmun kavitetsförstärkt optisk frekvenskamspektroskopi (NICE-OFCS), och uppnått en hagelbrusbegränsad känslighet och detektionsgränser ner till låga ppb koncentrationer (miljarddelar, 10−9) för CO2 i det när-infraröda frekvensområdet enbart med användning av kommersiellt tillgängliga komponenter. Vi har också utvecklat en ny metod för insamling och analys av kambaserade FTS-spektra, som betecknas ha sub-nominell upplösning. Metoden gör det möjligt att uppnå ultrahög spektral upplösning och hög frekvensnoggrannhet (båda i kHz-området, endast begränsad av kammens stabilitet) över kammens hela frekvensområde. Slutligen har vi utvecklat en optisk parametrisk oscillator som genererar en frekvenskam i det mid-infraröda frekvensområdet, där de starkaste rotations-vibrationsmolekylära absorptionslinjerna finns. Med hjälp av denna kam och en FTS har vi för första gången demonstrerat frekvenskamspektroskopi över 5 μm. Vi har detekterat bredbandsspektra av flera molekylära gaser och har, för mä

Optical frequency comb spectroscopy (OFCS) combines two previously exclusive features, i.e., wide optical bandwidth and high spectral resolution, enabling precise measurements of entire molecular bands and simultaneous monitoring of multiple gas species in a short measurement time. Moreover, the equidistant mode structure of frequency combs enables efficient coupling of the comb power to enhancement resonant cavities, yielding high detection sensitivities. Different broadband detection methods have been developed to exploit the full potential of frequency combs in spectroscopy, based either on Fourier transform spectroscopy or on dispersive elements.There have been two main aims of the research presented in this thesis. The first has been to improve the performance of mechanical Fourier transform spectrometers (FTS) based on frequency combs in terms of sensitivity, resolution and spectral coverage. In pursuit of this aim, we have developed a new spectroscopic technique, so-called noise-immune cavity-enhanced optical frequency comb spectroscopy (NICE-OFCS), and achieved a shot-noise-limited sensitivity and low ppb (parts-per-billion, 10−9) CO2 concentration detection limit in the near-infrared range using commercially available components. We have also realized a novel method for acquisition and analysis of comb-based FTS spectra, a so-called sub-nominal resolution method, which provides ultra-high spectral resolution and frequency accuracy (both in kHz range, limited only by the stability of the comb) over the broadband spectral range of the frequency comb. Finally, we have developed an optical parametric oscillator generating a frequency comb in the mid-infrared range, where the strongest ro-vibrational molecular absorption lines reside. Using this mid-infrared comb and an FTS, we have demonstrated, for the first time, comb spectroscopy above 5 μm, measured broadband spectra of several species and reached low ppb detection limits for CH4, NO and CO in 1 s.The secon, Optisk frekvenskamspektroskopi (OFCS) kombinerar två tidigare icke förenliga egenskaper, dvs. ett brett optiskt frekvensområde med en hög spektral upplösning, vilket möjliggör noggranna mätningar av hela molekylära absorptionsband och detektion av flera gaser samtidigt med en kort mättid. Eftersom frekvenskammar har en regelbunden struktur med jämnt separerade laser moder kan man effektivt koppla kammen till en optisk kavitet och därmed möjliggöra frekvenskamsdetektion med hög känslighet. Olika metoder har utvecklats för att utnyttja frekvenskammarnas fulla potential för spektroskopi, baserad på antingen Fouriertransform-spektroskopi eller dispersiva element.Forskningen som presenteras i denna avhandling har haft två huvudmål. Det första har varit att förbättra prestandan hos mekaniska Fourier-transformspektrometrar (FTS) baserat på frekvenskammar med avseende på känslighet, upplösning och spektral täckning. I strävan efter detta har vi utvecklat en ny spektroskopisk teknik, benämnd brusimmun kavitetsförstärkt optisk frekvenskamspektroskopi (NICE-OFCS), och uppnått en hagelbrusbegränsad känslighet och detektionsgränser ner till låga ppb koncentrationer (miljarddelar, 10−9) för CO2 i det när-infraröda frekvensområdet enbart med användning av kommersiellt tillgängliga komponenter. Vi har också utvecklat en ny metod för insamling och analys av kambaserade FTS-spektra, som betecknas ha sub-nominell upplösning. Metoden gör det möjligt att uppnå ultrahög spektral upplösning och hög frekvensnoggrannhet (båda i kHz-området, endast begränsad av kammens stabilitet) över kammens hela frekvensområde. Slutligen har vi utvecklat en optisk parametrisk oscillator som genererar en frekvenskam i det mid-infraröda frekvensområdet, där de starkaste rotations-vibrationsmolekylära absorptionslinjerna finns. Med hjälp av denna kam och en FTS har vi för första gången demonstrerat frekvenskamspektroskopi över 5 μm. Vi har detekterat bredbandsspektra av flera molekylära gaser och har, för mä

The rapidly growing demand for higher networking capacity and data rates is forcing researchers to explore the unused spectrum in the higher frequency bands. Two such bands, the millimeter wave (mmWave), ranging from 30 GHz to 300 GHz, and the Terahertz (THz) band, ranging from 0.1 THz to 10 THz, are currently being investigated for possible use in future networks. Because many atmospheric molecules have their natural resonant frequencies in these bands, it is important to understand the effects of molecular absorption and re-radiation on the wireless networking performance in such high frequency bands. Building on the recently discovered molecular absorption models, this thesis conducts a theoretical study on the effect of molecular absorption and re-radiation on both single-antenna and multiantenna wireless communications. For the single-antenna communication, the study focuses on quantifying the temporal and spatial variation of path loss and noise, which is caused by variation in the molecular composition in the air. In particular, it studies the extent of spatio-temporal variation of mmWave channels in three largest cities of Australia by investigating the hourly air quality and weather data over 12 months. The study finds that mmWave channels experience significant variation in both space and time domains, which causes undesirable network capacity fluctuation in various places and hours. For the multi-antenna communication, the study yields a new theoretical discovery that the Multiple-Input and Multiple-Output (MIMO) capacity can be significantly influenced by atmosphere molecules. In more detail, some common atmosphere molecules, such as Oxygen and water, can absorb and re-radiate energy in their natural resonant frequencies, such as 60 GHz, 120GHz and 180 GHz, which belong to the mmWave spectrum. Such phenomenon can provide equivalent Non-Line-of-Sight (NLoS) paths in an environment that is dominated by Line-of-Sight (LoS) transmissions, and thus greatly im

This paper describes the contents of the 2016 edition of the HITRAN molecular spectroscopic compilation. The new edition replaces the previous HITRAN edition of 2012 and its updates during the intervening years. The HITRAN molecular absorption compilation is composed of five major components: the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, collision-induced absorption data, aerosol indices of refraction, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, added line-shape formalisms, and validity. Moreover, molecules, isotopologues, and perturbing gases have been added that address the issues of atmospheres beyond the Earth. Of considerable note, experimental IR cross-sections for almost 300 additional molecules important in different areas of atmospheric science have been added to the database. The compilation can be accessed through www.hitran.org. Most of the HITRAN data have now been cast into an underlying relational database structure that offers many advantages over the long-standing sequential text-based structure. The new structure empowers the user in many ways. It enables the incorporation of an extended set of fundamental parameters per transition, sophisticated line-shape formalisms, easy user-defined output formats, and very convenient searching, filtering, and plotting of data. A powerful application programming interface making use of structured query language (SQL) features for higher-level applications of HITRAN is also provided., SCOPUS: ar.j, info:eu-repo/semantics/published

Impulse response of the terahertz band (0.1–10 THz) for wireless nanosensor networks is considered. For wireless communication analysis and modeling, the impulse response is very important. In the earlier works, the impulse response has been derived from the transmittance by assuming a linear phase shift. However, the linear phase shift only leads to a symmetric impulse response before and after the LoS propagation delay. Physically, it is impossible for a signal to arrive before the LoS propagation delay since this violates causality. In this paper, a phase shift function leading to an impulse response satisfying causality is derived. The validity of the derived model is shown by comparison between measurements and results predicted by the theory.

Graphene is enabling a plethora of applications in a wide range of fields due to its unique electrical, mechanical, and optical properties. In this context, graphene antennas are envisioned to enable ultra-high-speed wireless communication in short transmission ranges, due to both their reduced size and their radiation frequency in the terahertz band. Despite its high potential bandwidth, the terahertz band presents several phenomena that may impair the communication and reduce the achievable data rate. In this letter, the phenomenon of molecular absorption is quantitatively analyzed, evaluating the scalability of both time-and frequency-domain performance metrics with the transmission distance. The results of this analysis show that molecular absorption creates a tradeoff between the achievable throughput and the maximum transmission distance at which short-range terahertz wireless communications can successfully take place., Peer Reviewed, Postprint (author’s final draft)

Методом равновесного термодинамического моделирования изучены термохимические процессы, сопровождающие образование газообразных молекул SrF, Thermochemical processes accompanying the formation of gaseous molecules SrF

This paper describes the status of the latest edition of the HITRAN molecular spectroscopic compilation. The new edition is meant to replace the previous HITRAN edition of 2008 and its updates during the intervening years. The HITRAN molecular absorption compilation is comprised of six major components structured into folders that are freely accessible on the internet. These folders consist of the traditional line-by-line spectroscopic parameters required for high-resolution radiative-transfer codes, infrared absorption cross-sections for molecules not yet amenable to representation in a line-by-line form, ultraviolet spectroscopic parameters, aerosol indices of refraction, collision-induced absorption data, and general tables such as partition sums that apply globally to the data. The new HITRAN is greatly extended in terms of accuracy, spectral coverage, additional absorption phenomena, and validity. Molecules and isotopologues have been added that address the issues of atmospheres beyond the Earth. Also discussed is a new initiative that casts HITRAN into a relational database format that offers many advantages over the long-standing sequential text-based structure that has existed since the initial release of HITRAN in the early 1970s.

Optical frequency references are devices providing well-defined and stable optical frequency responses to incoming radiation for applications such as high-precision spectroscopy and optical fibre communications. To stabilise the emission frequency of lasers, which drifts with time mostly because of fluctuations in temperature and mechanical vibrations, atomic and molecular optical transitions can be used since they show precise and well-defined frequency responses to incoming radiation. However from a practical standpoint conventional gas cell devices cannot be easily integrated into existing optical systems because of their bulky dimensions. To replace conventional absorption cells, photonic crystal fibres filled with gas-phase material are promising devices owing to their robustness, reliability, and portable characteristics. In addition they can be directly embedded into existing optical systems and they perform well in harsh environments. In this experimental study, optical gas-phase frequency references based on photonic crystal technology are realised. The gas-sensing properties of different photonic crystal fibre samples are studied and the long-term stability and reliability of fibre gas cells are demonstrated. In addition an analytical model predicting the gas-filling time in photonic crystal fibres (PCF) is developed and can be applied to any type of fibre, fibre geometry, or length. Then fibre gas cells filled with acetylene gas, a recognised frequency reference gas-phase material, have been prepared to conduct fundamental research on slow & fast light generation in optical fibres to verify the possibilities of slow light in enhancing light-matter interaction. The group velocity of light is controlled by modifying the material and structural dispersive properties of the PCF absorption cells through stimulated Brillouin scattering and cavity ring resonators, respectively. We could demonstrate that material slow light has no impact on the molecular absorpti

The adsorption of dimethyl methylphosphonate (DMMP) on the (0 1 0) surface of anatase TiO2, which is isostructural with the (1 0 0), has been studied using density functional theory and two-dimensionally periodic slab models. The experimentally-observed faceting of this surface has, for the first time, been included in the modeling. The relaxations of bare surfaces both with and without faceting are similar leading to an atomic-scale roughening due to inward (outward) displacement of fivefold-coordinated Ti5c (sixfold-coordinated T6c) atoms together with outward displacement of threefold-coordinated O3c atoms. Molecular adsorption occurs by formation of a Ti5c O=P dative bond with one or more CAH O2c bonds between CH3 groups and unsaturated, twofold-coordinated (O2c) sites. The energies for molecular adsorption, obtained using the B3LYP functional, are virtually identical (about 21.0 kcal/mol) for the two surfaces and are also close to those found elsewhere for the rutile (1 1 0) and anatase (1 0 1) surfaces. A possible first step in the dissociative adsorption of DMMP has also been modeled and is found to be thermodynamically favored over molecular adsorption to a degree which depends on faceting., Published in the Journal of Surface Science, v604 p706-712, 2010. Supported in part by ARL and DOD.

This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e. spectra in which the individual lines are not resolved; individual line parameters and absorption cross-sections for bands in the ultraviolet; refractive indices of aerosols, tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 42 molecules including many of their isotopologues. © 2009 Elsevier Ltd., SCOPUS: ar.j, info:eu-repo/semantics/published

This paper describes the status of the 2008 edition of the HITRAN molecular spectroscopic database. The new edition is the first official public release since the 2004 edition, although a number of crucial updates had been made available online since 2004. The HITRAN compilation consists of several components that serve as input for radiative-transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e. spectra in which the individual lines are not resolved; individual line parameters and absorption cross-sections for bands in the ultraviolet; refractive indices of aerosols, tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 42 molecules including many of their isotopologues. © 2009 Elsevier Ltd., SCOPUS: ar.j, info:eu-repo/semantics/published

A characteristic nondimensional distortion number Nd was derived in the 1970s that allows inference of the degree of nonlinear refraction or thermal blooming associated with an atmospheric laser path. For a continuous-wave (CW) laser with a Gaussian-shaped beam, the distortion number is a function of several variables including laser power and aperture size, optical wavelength, atmospheric absorption and extinction, index of refraction, temperature, air density, and the air speed or flow transverse to the laser beam. Scenario-dependent calculations of atmospheric distortion number Nd are developed for different geographic regions and seasons using the Air Force Research Laboratory's global thermosonde database, the HITRAN molecular spectroscopic database, and global climatological aerosol model extinction profiles. Tactical air-to-ground scenarios are described as a function of altitude, target distance, and laser-to-target azimuth angle for the COIL wavelength (1.315 micrometers). The results are interpreted in light of seasonal and geographical factors as well as path-integrated moisture., Published in the Journal of Directed Energy, v2 n3 p211-223, 2007. ISSN 1546-0185. Prepared in collaboration with Air Force Research Laboratory (AFRL), Hanscom AFB, MA. Sponsored in part by the DoD High Energy Laser Joint Technology Office (HEL-JTO).

This paper describes the status of the 2004 edition of the HITRAN molecular spectroscopic database. The HITRAN compilation consists of several components that serve as input for radiative transfer calculation codes: individual line parameters for the microwave through visible spectra of molecules in the gas phase; absorption cross-sections for molecules having dense spectral features, i.e., spectra in which the individual lines are unresolvable; individual line parameters and absorption cross-sections for bands in the ultra-violet; refractive indices of aerosols; tables and files of general properties associated with the database; and database management software. The line-by-line portion of the database contains spectroscopic parameters for 39 molecules including many of their isotopologues. The format of the section of the database on individual line parameters of HITRAN has undergone the most extensive enhancement in almost two decades. It now lists the Einstein A-coefficients, statistical weights of the upper and lower levels of the transitions, a better system for the representation of quantum identifications, and enhanced referencing and uncertainty codes. In addition, there is a provision for making corrections to the broadening of line transitions due to line mixing. (C) 2005 Elsevier Ltd. All rights reserved.

This paper describes the status circa 2001, of the HITRAN compilation that comprises the public edition available through 2001. The HITRAN compilation consists of several components useful for radiative transfer calculation codes: high-resolution spectroscopic parameters of molecules in the gas phase, absorption cross-sections for molecules with very dense spectral features, aerosol refractive indices, ultraviolet line-by-line parameters and absorption cross-sections, and associated database management software. The line-by-line portion of the database contains spectroscopic parameters for 38 molecules and their isotopologues and isotopomers suitable for calculating atmospheric transmission and radiance properties. Many more molecular species are presented in the infrared cross-section data than in the previous edition, especially the chlorofluorocarbons and their replacement gases. There is now sufficient representation so that quasi-quantitative simulations can be obtained with the standard radiance codes. In addition to the description and justification of new or modified data that have been incorporated since the last edition of HITRAN (1996), future modifications are indicated for cases considered to have a significant impact on remote-sensing experiments. (C) 2003 Elsevier Ltd. All rights reserved.

A polarized IR scattering facility that measures all elements of the Mueller matrix was built here at the U.S. Army Chemical Research, Development and Engineering Center (CRDEC) for remote detection of contaminants (analytes) spread on natural and manufactured surfaces (background scattering interferent). The ellipsometer is a two-modulator design that when interfaced to a mathematical algorithm can be trained to emit beam CO2 laser energies at incident angles that best contrast various analyte target backscattering signatures from background signatures. For a probable detection event, sets of Mueller matrices are measured at beam energies coinciding with resonant IR absorptions by the analyte and at incident angle where backscattering by that analyte surface is strong. Identification of the contaminant(s) in situ is determined by another algorithm that operates on a vector whose N is equal or more than 16 components are the independent Mueller elements measured at the susceptible beam energy/angle parameters. This work documents the phase sensitive detection program at CRDEC from past developments to future applications., Original contains color plates: All DTIC/NTIS reproductions will be in black and white. Prepared in cooperation with University of Nebraska, Lincoln, NE 65808

Atmospheric attenuation at visible wavelengths in polluted atmospheres cannot necessarily be predicted accurately from visibility statistics. This report discusses human vision under different lighting conditions. The eye has much less than its maximum sensitivity where molecular absorption by pollutants is strongest. However, it was concluded that molecular absorption at visible wavelengths is rarely large enough to be a serious problem. Scattering is the primary cause of low visibilities in the atmosphere. Scattering is also the main cause of really large extinction coefficients throughout the visible portion of the spectrum.

Photoelectron spectra for ammonia adsorbed in submonolayer and multilayer amounts on clean and oxidized aluminum have been measured and interpreted. Uptake at 128K is dominated by weak molecular adsorption and saturates at submonolayer amounts whereas at 106K multilayers can be formed. On oxidized A1, as compared to clean, the saturation amount of adsorbed NH3 is larger and it is more tightly held. On clean A1, there is good evidence that NH3 tends to be physisorbed with the major bonding arising between the dipole of NH3 and the image dipole induced in the metal.(Author)

A study is made of two basically distinct methods normally used in the development of band models for the calculation of gaseous molecular transmittance in the infrared region. The first method consists of the determination of the 'empirical' transmittance function and the associated absorber and spectral parameters from measured or calculated transmittance spectra. The second method consists of the determination of the absorber and spectral parameters with an assumed 'analytical' transmittance function, using the same type of data. Computerized numerical techniques are presented in connection with the first method and a generalized transmittance function is adopted for the second method. Although the methodology is generally applicable to other gaseous species, it is specifically discussed in connection with the trace gases SO2, NO, NO2, and NH3. As a secondary effort a structural breakdown of the Lowtran code is presented for the purpose of incorporating the band models for the trace gases.

This report describes progress on the various tasks which comprise the research in laser atmospheric propagation. This work includes 1. a review of work done on the study of the infrared water vapor continuum, 2. the design of low stain-less steel, temperature controlled absorption cells with White-type optics, 3. design of a non-resonant, differential spectrophone and data recorded on this instrument, 4. design of a stainless steel resonant spectrophone, 5. and other topics.

This report discusses proposed molecular transmittance band models for the uniformly mixed gases dinitrogenoxide, methane, carbon monoxide, oxygen and carbondioxide, the trace gases Nitrausoxide, ammonia and sulfide water vapor, and ozone in the infrared. The models are specifically designed for direct incorporation into LOWTRAN 6 atmospheric transmission code. (keywords: Molecules; Absorption, Infrared; Bands; Models; Concentration; profiles; gases.

Uvedená diplomová práce rozebírá problematiku optických laserových dálkoměrů ve skutečném přenosovém prostředí. Popisuje jednotlivé díly optických laserových dálkoměrů jejich vlastnosti a principy v návaznosti na jejich výkonovou bilanci. V práci jsou uvedeny základní optické vlastnosti čoček používaných ve vysílači a přijímači. Samostatná kapitola je věnována metodě tranzitního času a faktorům ovlivňujícím měření. Součástí diplomové práce je rozbor poměrné směrové odrazivosti. V závěru diplomové práce jsou uvedeny praktické laboratorní výsledky měření poměrné směrové odrazivosti různých materiálů a barev. Na základě naměřených hodnot byl ověřen výkonový úrovňový diagram dálkoměru., The thesis analyzes the optical laser range finders in real propagation environments. Itdescribes the various parts of optical laser range finders their properties and principles in relation to their performance balance. The paper presents the basic optical properties of lenses used in the transmitter and receiver. A separate chapter is devoted to the transit time method and factors influencing the measurement. The proportional directional reflectance analysisis a part of the thesis. In conclusion, the thesis contains the practical laboratory measurements of the relative directional reflectance of different materials and colors, and verification of the power level diagram.

Uvedená diplomová práce rozebírá problematiku optických laserových dálkoměrů ve skutečném přenosovém prostředí. Popisuje jednotlivé díly optických laserových dálkoměrů jejich vlastnosti a principy v návaznosti na jejich výkonovou bilanci. V práci jsou uvedeny základní optické vlastnosti čoček používaných ve vysílači a přijímači. Samostatná kapitola je věnována metodě tranzitního času a faktorům ovlivňujícím měření. Součástí diplomové práce je rozbor poměrné směrové odrazivosti. V závěru diplomové práce jsou uvedeny praktické laboratorní výsledky měření poměrné směrové odrazivosti různých materiálů a barev. Na základě naměřených hodnot byl ověřen výkonový úrovňový diagram dálkoměru., The thesis analyzes the optical laser range finders in real propagation environments. Itdescribes the various parts of optical laser range finders their properties and principles in relation to their performance balance. The paper presents the basic optical properties of lenses used in the transmitter and receiver. A separate chapter is devoted to the transit time method and factors influencing the measurement. The proportional directional reflectance analysisis a part of the thesis. In conclusion, the thesis contains the practical laboratory measurements of the relative directional reflectance of different materials and colors, and verification of the power level diagram.

Computer programs have been developed for calculation of the molecular absorption and aerosol extinction for horizontal path propagation of radiation in the wavelength range above 0.55 µm. The AFCRL line parameters compilation is used as input data with local weather conditions for the Monterey Bay and model of typical aerosol size distribution from Shettle and Fenn. Wind speed and relative humidity are included in the form developed by Wells, Gal and Munn. Infinite resolution computations have been carried out for 1.06, 3.8 and 10.6 µm and results tabulated for monthly and yearly average weather conditions on Monterey Bay. Bandwidth-averaged spectral transmittances have been calcu­lated at 0.01 cm-l and 0.5 cm-l resolution for the same conditions. Comparisons with previously published data show agreement to 1.8% with maritime model aerosol Mie-scattering calculations by Selby using LOWTRAN III B [Ref. 12]. Analysis of sensitivity to changes of pressure and temperature for the 3.8 µm range showed only small effects of these parameters. However a change in water vapor partial pressure results in a 0.75%/mbar change in transmittance in the 3.8 µm region., http://archive.org/details/highresolutionco1094518450, Lieutenant, Turkish Navy, Approved for public release; distribution is unlimited.

Uvedená diplomová práce rozebírá problematiku optických laserových dálkoměrů ve skutečném přenosovém prostředí. Popisuje jednotlivé díly optických laserových dálkoměrů jejich vlastnosti a principy v návaznosti na jejich výkonovou bilanci. V práci jsou uvedeny základní optické vlastnosti čoček používaných ve vysílači a přijímači. Samostatná kapitola je věnována metodě tranzitního času a faktorům ovlivňujícím měření. Součástí diplomové práce je rozbor poměrné směrové odrazivosti. V závěru diplomové práce jsou uvedeny praktické laboratorní výsledky měření poměrné směrové odrazivosti různých materiálů a barev. Na základě naměřených hodnot byl ověřen výkonový úrovňový diagram dálkoměru., The thesis analyzes the optical laser range finders in real propagation environments. Itdescribes the various parts of optical laser range finders their properties and principles in relation to their performance balance. The paper presents the basic optical properties of lenses used in the transmitter and receiver. A separate chapter is devoted to the transit time method and factors influencing the measurement. The proportional directional reflectance analysisis a part of the thesis. In conclusion, the thesis contains the practical laboratory measurements of the relative directional reflectance of different materials and colors, and verification of the power level diagram.

Uvedená diplomová práce rozebírá problematiku optických laserových dálkoměrů ve skutečném přenosovém prostředí. Popisuje jednotlivé díly optických laserových dálkoměrů jejich vlastnosti a principy v návaznosti na jejich výkonovou bilanci. V práci jsou uvedeny základní optické vlastnosti čoček používaných ve vysílači a přijímači. Samostatná kapitola je věnována metodě tranzitního času a faktorům ovlivňujícím měření. Součástí diplomové práce je rozbor poměrné směrové odrazivosti. V závěru diplomové práce jsou uvedeny praktické laboratorní výsledky měření poměrné směrové odrazivosti různých materiálů a barev. Na základě naměřených hodnot byl ověřen výkonový úrovňový diagram dálkoměru., The thesis analyzes the optical laser range finders in real propagation environments. Itdescribes the various parts of optical laser range finders their properties and principles in relation to their performance balance. The paper presents the basic optical properties of lenses used in the transmitter and receiver. A separate chapter is devoted to the transit time method and factors influencing the measurement. The proportional directional reflectance analysisis a part of the thesis. In conclusion, the thesis contains the practical laboratory measurements of the relative directional reflectance of different materials and colors, and verification of the power level diagram.

Uvedená diplomová práce rozebírá problematiku optických laserových dálkoměrů ve skutečném přenosovém prostředí. Popisuje jednotlivé díly optických laserových dálkoměrů jejich vlastnosti a principy v návaznosti na jejich výkonovou bilanci. V práci jsou uvedeny základní optické vlastnosti čoček používaných ve vysílači a přijímači. Samostatná kapitola je věnována metodě tranzitního času a faktorům ovlivňujícím měření. Součástí diplomové práce je rozbor poměrné směrové odrazivosti. V závěru diplomové práce jsou uvedeny praktické laboratorní výsledky měření poměrné směrové odrazivosti různých materiálů a barev. Na základě naměřených hodnot byl ověřen výkonový úrovňový diagram dálkoměru., The thesis analyzes the optical laser range finders in real propagation environments. Itdescribes the various parts of optical laser range finders their properties and principles in relation to their performance balance. The paper presents the basic optical properties of lenses used in the transmitter and receiver. A separate chapter is devoted to the transit time method and factors influencing the measurement. The proportional directional reflectance analysisis a part of the thesis. In conclusion, the thesis contains the practical laboratory measurements of the relative directional reflectance of different materials and colors, and verification of the power level diagram.