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Research Output 2001 2019

2019

Laser transmitter for cubesat-class applications

Crabb, J. R., Stevens, G., Michie, C., Johnstone, W. & Kehayas, E., 4 Mar 2019, In : Proceedings of SPIE. 10910, 8 p., 109101I.

Research output: Contribution to journalConference Contribution

Open Access
File
Transmitter
transmitters
Transmitters
Laser
Laser Communication
2018

All-optical fiber multi-point photoacoustic spectroscopic gas sensing system

Zhang, C., Yang, Y., Lin, Y., Tan, Y., Lengden, M., Humphries, G., Johnstone, W., Lut Ho, H. & Jin, W., 28 Sep 2018, Proceedings 26th International Conference on Optical Fiber Sensors. Washington, DC: Optical Society of America, 4 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

Open Access
File
Photoacoustic spectroscopy
Photoacoustic effect
Optical fibers
optical fibers
Sensors

A new RAM normalized 1f-WMS technique for the measurement of gas parameters in harsh environments and a comparison with 2f/1f

Upadhyay, A., Lengden, M., Wilson, D., Humphries, G. S., Crayford, A. P., Pugh, D. G., Johnson, M. P., Stewart, G. & Johnstone, W., 27 Nov 2018, In : IEEE Photonics Journal. 10, 6, 12 p., 6804611.

Research output: Contribution to journalArticle

Open Access
File
Random access storage
Modulation
Spectroscopy
modulation
Wavelength

CIDAR: combustion species imaging diagnostics for aero-engine research

Archilla, V., Aragón, G., Wright, P., Ozanyan, K., Black, J., Polydorides, N., McCann, H., Lengden, M., Burns, I., Johnstone, W., Polo, V., Beltran, M., Mauchline, I., Walsh, D. & Johnson, M., 18 Jun 2018. 1 p.

Research output: Contribution to conferencePaper

Open Access
File
Bypass ratio
Engines
Imaging techniques
Exhaust systems (engine)
Aircraft engines

CIDAR project - development of a non-intrusive capability for aircraft engine measurements

Archilla, V., Aragón, G., Wright, P., Ozanyan, K., Black, J., Lengden, M., Burns, I., Johnstone, W., Polo, V., Beltran, M. & Johnson, M., 18 Jun 2018. 1 p.

Research output: Contribution to conferencePaper

Open Access
File
Bypass ratio
Aircraft engines
Engines
Imaging techniques
Temperature distribution
2017
7 Citations (Scopus)
Open Access
File
Distributed feedback lasers
Surface emitting lasers
Modulation
Spectroscopy
Calibration
3 Citations (Scopus)

Constrained models for optical absorption tomography

Polydorides, N., Tsekenis, A., Fisher, E., Chigine, A., McCann, H., Dimiccoli, L., Wright, P., Lengden, M., Benoy, T., Wilson, D., Humphries, G. & Johnstone, W., 23 Oct 2017, In : Applied Optics. 57, 7, p. B1-B9 9 p.

Research output: Contribution to journalArticle

Open Access
File
optical absorption
tomography
projection
pencil beams
image reconstruction
1 Citation (Scopus)

Measurement of CO2 concentration and temperature in an aero engine exhaust plume using wavelength modulation spectroscopy

Benoy, T., Wilson, D., Lengden, M., Armstrong, I., Stewart, G. & Johnstone, W., 1 Oct 2017, In : IEEE Sensors Journal. 17, 19, p. 6409-6417 9 p.

Research output: Contribution to journalArticle

Open Access
File
Exhaust systems (engine)
plumes
engines
Modulation
Spectroscopy
2016
6 Citations (Scopus)
Open Access
File
Laser spectroscopy
Amplitude modulation
laser spectroscopy
line shape
Semiconductor lasers
5 Citations (Scopus)
Open Access
File
Distributed feedback lasers
distributed feedback lasers
line shape
recovery
Modulation

Trace gas sensing using DFB laser and QCL with miniaturized 3D-printed photoacoustic gas cells

Bauer, R., Flockhart, G. M. H., Johnstone, W. & Lengden, M., 8 Dec 2016, International Conference on Fibre Optics and Photonics 2016. Washington: Optical Society of America, 3 p. W4G.3

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

Open Access
File
Photoacoustic effect
Distributed feedback lasers
Chemical sensors
cells
Gases

Working towards cleaner air travel: the technology behind the FLITES project

Wilson, D., Humphries, G. S., Benoy, T., Lengden, M., Johnstone, W., Tsekenis, A., Fisher, E., Chigine, A., McCann, H., Feng, Y., Nilsson, J., Wright, P., McCormick, D., Ozanyan, K., Archilla Prat, V., Johnson, M. & Black, J., 12 Sep 2016.

Research output: Contribution to conferenceSpeech

Air cleaners
Imaging systems
Engines
Turbofan engines
Exhaust systems (engine)
2015
8 Citations (Scopus)

An FPGA-based lock-in detection system to enable chemical species tomography using TDLAS

Chighine, A., Fisher, E., Wilson, D., Lengden, M., Johnstone, W. & McCann, H., Sep 2015, 2015 IEEE International Conference on Imaging Systems and Techniques (IST). Piscataway, NJ: IEEE, p. 1-5 5 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

Open Access
File
Laser spectroscopy
Absorption spectroscopy
Tomography
Semiconductor lasers
Field programmable gate arrays (FPGA)

Fibre laser imaging of gas turbine exhaust species – a review of CO2 aero engine imaging

Lengden, M., Wilson, D., Armstrong, I., Benoy, T. & Johnstone, W., Jul 2015.

Research output: Contribution to conferencePoster

Fiber lasers
Gas turbines
Light sources
Engines
Imaging techniques
Photoacoustic spectroscopy
Photoacoustic effect
Solid oxide fuel cells (SOFC)
Process control
Laser spectroscopy
11 Citations (Scopus)

Miniaturized photoacoustic trace gas sensing using a raman fiber amplifier

Bauer, R., Legg, T., Mitchell, D., Flockhart, G. M. H., Stewart, G., Johnstone, W. & Lengden, M., 15 Sep 2015, In : Journal of Lightwave Technology. 33, 18, p. 3773-3780 9 p.

Research output: Contribution to journalArticle

Open Access
File
Fiber amplifiers
Photoacoustic effect
Photoacoustic spectroscopy
Seed
Stimulated Brillouin scattering
Photoacoustic effect
Chemical sensors
Infrared radiation
Gases

MIR photoacoustic trace gas sensing using a miniaturized 3D printed gas cell

Bauer, R., Wilson, D., Johnstone, W. & Lengden, M., 2015, Advanced Photonics 2015, OSA Technical Digest: Optical Sensors 2015. Optical Society of America, 3 p. SeT1C.3

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

Photoacoustic effect
Chemical sensors
Infrared radiation
Gases
11 Citations (Scopus)

Progress towards non-intrusive optical measurement of gas turbine exhaust species distributions

Wright, P., McCormick, D., Ozanyan, K., Johnson, M., Black, J., Fisher, E., Chighine, A., Polydorides, N., McCann, H., Feng, Y., Khan, K., Bastock, P., Jia, F., Hewak, D., Nilsson, J., Lengden, M., Wilson, D., Armstrong, I., Benoy, T. & Johnstone, W., 7 Mar 2015, Aerospace Conference, 2015 IEEE . IEEE, p. 1-14 14 p.

Research output: Chapter in Book/Report/Conference proceedingConference contribution book

Open Access
File
Gas turbines
Soot
Civil aviation
Hydrocarbons
Environmental impact
2014
22 Citations (Scopus)

A 3D-printed miniature gas cell for photoacoustic spectroscopy of trace gases

Bauer, R., Stewart, G., Johnstone, W., Boyd, E. & Lengden, M., 8 Aug 2014, In : Optics Letters. 39, 16, p. 4796-4799 4 p.

Research output: Contribution to journalLetter

Open Access
File
photoacoustic spectroscopy
cells
gases
distributed feedback lasers
collimators

LD-seeded thulium-doped fibre amplifier for CO2 measurements at 2 µm

Feng, Y., Nilsson, J., Jain, S., May-Smith, T. C., Sahu, J. K., Jia, F., Benoy, T., Wilson, D., Lengden, M. & Johnstone, W., Aug 2014. 1 p.

Research output: Contribution to conferencePaper

Open Access
File
Thulium
Fiber amplifiers
Tomography
Jet engines
Exhaust systems (engine)

Near IR tunable diode laser spectroscopy for aero engine research

Benoy, T., Lengden, M., Armstrong, I., Wilson, D., Stewart, G. & Johnstone, W., May 2014.

Research output: Contribution to conferencePoster

cells
gases
photoacoustic spectroscopy
resonators
interrogation
2 Citations (Scopus)
Open Access
File
Passive optical networks
power loss
transmitters
division
aircraft
2013
Laser spectroscopy
Solid oxide fuel cells (SOFC)
Semiconductor lasers
Engines
Monitoring
8 Citations (Scopus)

Tunable diode laser based concentration measurements of water vapour and methane on a solid oxide fuel cell

Lengden, M., Cunningham, R. & Johnstone, W., 1 May 2013, In : Journal of Lightwave Technology. 31, 9, p. 1354 - 1359 7 p.

Research output: Contribution to journalArticle

solid oxide fuel cells
Solid oxide fuel cells (SOFC)
Water vapor
Semiconductor lasers
water vapor
2012
laser spectroscopy
line of sight
plumes
water vapor
engines

Measurement of key species in gas turbine engine exhaust plumes

Lengden, M., Armstrong, I., Bain, J. & Johnstone, W., 23 Oct 2012.

Research output: Contribution to conferencePoster

gas turbine engines
plumes
engines
gases
solid oxide fuel cells
2011

Development of a TDLS-based ambient water vapour sensor for aeroengine intake temperature determination

Bain, J. R. P., Lengden, M., Stewart, G., Black, J. & Johnstone, W., 1 Jul 2011, (Unpublished).

Research output: Contribution to conferencePoster

water vapor
sensors
temperature
modulation
test chambers
Solid oxide fuel cells (SOFC)
Process control
Chemical analysis
Gases

High temperature investigations of methane for the calculation of the temperature dependence of spectral parameters

Lengden, M., Johnstone, W., Bain, J. R. P. & Milne, L., Jul 2011, (Unpublished).

Research output: Contribution to conferencePoster

methane
temperature dependence
high temperature environments
gas composition
pressure measurement
9 Citations (Scopus)

Intra-cavity spectroscopy using amplified spontaneous emission in fiber lasers

Arsad, N., Min, L., Stewart, G. & Johnstone, W., 1 Mar 2011, In : Journal of Lightwave Technology. 29, 5, p. 782-788 7 p.

Research output: Contribution to journalArticle

Open Access
File
spontaneous emission
fiber lasers
cavities
gases
spectroscopy

Measurement of aeroengine intake gas temperature using TDLS of atmospheric water vapour

Bain, J., Lengden, M., Black, J. & Johnstone, W., 13 Sep 2011.

Research output: Contribution to conferencePoster

gas temperature
water vapor
36 Citations (Scopus)
laser spectroscopy
line shape
recovery
diodes
modulation
44 Citations (Scopus)

Recovery of absolute gas absorption line shapes using tuneable diode laser spectroscopy with wavelength modulation- part 1: theoretical analysis

Stewart, G., Johnstone, W., Bain, J. R. P., Ruxton, K. C. & Duffin, K., 15 Mar 2011, In : Journal of Lightwave Technology. 29, 6, p. 811-821 11 p.

Research output: Contribution to journalArticle

Gas absorption
Laser spectroscopy
laser spectroscopy
line shape
Semiconductor lasers
1 Citation (Scopus)

Semiconductor optical amplifiers in avionics

Michie, W., Johnstone, W., Andonovic, I., Murphy, E., White, H. & Kelly, A., 18 Nov 2011, p. 73-74. 2 p.

Research output: Contribution to conferencePaper

Open Access
File
avionics
light amplifiers
S band
C band
ultrahigh frequencies
Laser spectroscopy
Process control
Semiconductor lasers
Water vapor
Methane
6 Citations (Scopus)

Tuneable diode laser gas analyser for methane measurements on a large scale solid oxide fuel cell

Lengden, M., Cunningham, R. & Johnstone, W., Oct 2011, In : Journal of Power Sources. 196, 20, p. 8406-8408 3 p.

Research output: Contribution to journalLetter

gas lasers
Methane
solid oxide fuel cells
Solid oxide fuel cells (SOFC)
Semiconductor lasers
2010
14 Citations (Scopus)

Detection of CH4 in the mid-IR using difference frequency generation with tunable diode laser spectroscopy

Armstrong, I., Johnstone, W., Duffin, K., Lengden, M., Chakraborty, A. L. & Ruxton, K. C., 15 May 2010, In : Journal of Lightwave Technology. 28, 10, p. 1435-1442 8 p.

Research output: Contribution to journalArticle

laser spectroscopy
diodes
methane
wavelengths
11 Citations (Scopus)

Influence of the wavelength-dependence of fiber couplers on the background signal in wavelength modulation spectroscopy with RAM-nulling

Chakraborty, A. L., Ruxton, K. C. & Johnstone, W., 4 Jan 2010, In : Optics Express. 18, 1, p. 267-280 14 p.

Research output: Contribution to journalArticle

couplers
modulation
fibers
elimination
wavelengths

In-situ, real time gas composition measurements for SOFC's using laser spectroscopy

Lengden, M., Johnstone, W. & Cunningham, R., Jul 2010, (Unpublished).

Research output: Contribution to conferencePaper

File
Laser spectroscopy
Solid oxide fuel cells (SOFC)
Chemical analysis
Gases
Gas chromatography
9 Citations (Scopus)
Open Access
File
Near-infrared Spectroscopy
Near infrared spectroscopy
Gases
infrared spectroscopy
Fiber

Power requirements and operation of amplified optical networks for future aerospace applications

Proudfoot, A. D., Michie, C., Johnstone, W. & White, H. J., Sep 2010, p. 17-18. 2 p.

Research output: Contribution to conferencePaper

Aerospace applications
Fiber optic networks
Amplification
Wavelength
Semiconductor optical amplifiers
Gas fuel measurement
Elimination
Spectroscopy
elimination
Modulation
15 Citations (Scopus)

Suppression of intensity modulation contributions to signals in second harmonic wavelength modulation spectroscopy

Chakraborty, A. L., Ruxton, K. C. & Johnstone, W., 8 Jul 2010, In : Optics Letters. 35, 14, p. 2400-2402 2 p.

Research output: Contribution to journalArticle

retarding
harmonics
modulation
wavelengths
spectroscopy

The operation and power budget of amplified optical networks for aerospace applications

Proudfoot, A. D., Michie, C., Johnstone, W. & White, H. J., 1 May 2010, (Unpublished).

Research output: Contribution to conferencePaper

Aerospace applications
Fiber optic networks
34 Citations (Scopus)

Tunable diode laser spectroscopy with wavelength modulation: elimination of residual amplitude modulation in a phasor decomposition approach

Ruxton, K. C., Chakraborty, A. L., Johnstone, W., Lengden, M., Stewart, G. & Duffin, K., 21 Sep 2010, In : Sensors and Actuators B: Chemical. 150, 1, p. 367-375 9 p.

Research output: Contribution to journalArticle

Laser spectroscopy
Amplitude modulation
laser spectroscopy
Semiconductor lasers
elimination
34 Citations (Scopus)

Tunable diode laser spectroscopy with wavelength modulation: an overview of current techniques and motivations

Stewart, G., Ruxton, K. C., Chakraborty, A. & Johnstone, W., 23 Aug 2010.

Research output: Contribution to conferenceAbstract

laser spectroscopy
industries
diodes
modulation
wavelengths