Measuring Environmental Conditions Using LIDAR
June 12, 2020
Air, land and sea: What satellite imagery can’t do, LIDAR can.
Technologies help us measure, monitor, and understand our changing environment. While satellites are helping to image our planet, there are gaps. Remote sensing technologies, deployed on airborne, land-based, and undersea platforms, can provide range measurements that when combined with position data offer accurate, 3D coordinates and elevations that are helping to enable new science in environmental characterization.
Measuring air pollution
Countries around the world, particularly China, are investing in pollution control to detect, monitor, and inform differing levels of air quality. Recently, the COVID-19 pandemic forced stay-at-home orders, resulting in significant reductions in air pollutants - from both vehicle emissions and industrial plants - across urban and residential areas. As the country recovers, air quality gains reverse.
Airborne or land-based lidar can be used to generate a 3D image of the atmosphere, mapping levels of smog and other conditions. This technology can be used to monitor pollutants coming from stationary sources such as coal power plants, mobile sources, fires and motor vehicles. Lidar helps monitor the distribution of particles, dust, and other pollutants around the source.
Ocean exploration and conservation
Bathymetric lidar technologies must operate within 1-10kHz, requiring a unique combination of energy levels and pulsewidths. To maximize the resolution of the images, Quantum Composers designed the Spectrolite 10kHz blue laser – a non-standard line for Nd:YAG pulsed lasers - which was used to reduce interference from scattered light. Encased in a pod, a scanner can travel the ocean floor in a grid pattern, looking for sources of pollution, methane seeps, leaks and spills, and marine life.
Methane leak detection
LIDAR systems provide the oil and gas sector with a highly sensitive, accurate way of detecting methane leaks along a gas supply line. The ability to quickly detect and localize leaks helps ensure safety and reduce waste. In this instance, an airborne-based, manned or unmanned long-range system is used to characterize a 5+ mile range.
Lidar Technology for Environmental Research
While LIDAR has prompted a great deal of interest in pursuit of autonomous vehicles, this remote sensing method has a long-standing history in atmospheric research. Quantum Composers was involved in the development of the first such system in the 1990s, designed to measure smog conditions at the Barcelona Olympics. This system was used to capture 3D imagery at a range of 4-5 miles. Since that time, LIDAR systems, whether airborne or ground-based, have dropped in cost by an order of magnitude, which broadens their potential applications.
Thanks to the automotive and telecom industries, which has driven down the cost of components, the same system used in Barcelona that might have cost $250,000 at the time could be achieved for $10,000. This is due to:
Diode technology: Now higher power, less expensive and more reliable
Detector cost reduction
High volume manufacturing methods
While LIDAR systems for automotive have helped to enable LIDAR for environmental research, there are key differences to consider in laser system design:
Range: Automotive targets the 200-400 m range, while research lasers like the Spectrolite measure range in miles, not meters. Two factors determine the system’s optimal working range: energy and beam quality.
Energy: Laser energy and rep rate determine the LIDAR range and data rate, which ultimately determines the power and size of the system. For compact, portable systems the laser parameters should be optimized for each application.
Timing: Proper synchronization between the laser, light collection, and detector can greatly enhance the efficacy of a system and analysis result. LIDAR requires high precision, high-speed timing circuitry. Quantum Composers high precision timing boards offer picosecond timing resolution and low jitter.
Data rate: The right match in diagnostic receiver electronics can allow you to cover more ground and obtain more data in the same amount of time.
Environmental monitoring technologies are ever in demand, driving innovations such as increasingly powerful laser diodes which deliver improved performance at lower costs and in smaller packages.
Quantum Composers provides innovation and value to our customers with its diverse family of Precision Pulse Generators. Our line of synchronizers offer flexibility in both cost and performance to meet the requirements of any LIDAR experiment. We also offer custom system and component design from concept to production. Contact us today to learn how Quantum Composers can fulfill your laser or imaging system.
Learn about these and other applications for pulse generators here.