NOX Box - NIR Reflectance Measurements

The NOX is a NIR reflectance box that enables the continuous observation of Up-welling and Down-welling radiance in the visible to near infrared region (1650nm). It measures spectral data of high resolution (approximately 3 nm), yet is built to withstand the hazards of a permanent outdoor installation. It is fully autonomous in its operation, housed inside a rugged weatherproof case with low power consumption.

The NOX is an extension of the ROX system. It is typically installed on tripods or towers with upward channel pointing at the sky and downward channel pointing at the target. The NOX is specifically designed to measure radiance and reflectance under natural light conditions. Therefore the design is optimized to achieve maximum efficiency in terms of: Signal to Noise Ratio, Spectral Resolution and quick acquisition time. Different combination of spectrometers from Ocean Optics can be selected by the users (e.g. SR4, FLAME, QEpro for the visible range. FLAME-NIR or NIRquest for the NIR range). It is a robust and flexible system suitable for numerous applications including vegetation canopy monitoring and monitoring of water quality, snow and ice.

Details

NOX is saving raw data. To convert it into radiance and compute reflectance and a variety of vegetation indices, an open source R package is available. A graphical user interface makes the data processing easy for any customer to allow processing of years of data with a few clicks.

The basic NOX is equipped with a USB interface to stream data directly to a connected computer. The NOX is also able to pass a sub selection of variables (VIs and vital data) via SDI-12. The optional embedded PC, if connected to internet (LAN, WLAN, mobile network) will allow daily data stream of the full data set.

Applications

Field measurements of Spectral Reflectance from Vegetation.
Monitoring Plant Reflective Indices over wide range of irradiance (NDVI; PRI; MCARI; SRPI etc.)
Ground-truthing satellite data.
Cryosphere studies
Snow properties and melt prediction.
Water quality of lakes and rivers
Algal blooms

Specifications

OPTIC SPEC 1

Wavelength range: VIS-NIR: ~ 350-1100 nm (other options also available on demand)
Spectral Sampling Interval (SSI): ~ 0.7 nm
Spectral resolution (FWHM): ~ 3 nm
Signal to Noise Ratio (SNR): ~ 1000
Field Of View (FOV): Dual FOF – Upwelling radiance ~ 25°,Downwelling radiance 180°

OPTIC SPEC 2

Wavelength range: ~ 900-1650 nm
Spectral Sampling Interval (SSI): ~ 1.5 nm
Spectral resolution (FWHM): ~ 3 nm
Signal to Noise Ratio (SNR): ~ 300
Field Of View (FOV): Dual FOV – Upwelling radiance ~ 25°,Downwelling radiance 180°

OPERATIONAL

Signal Optimization: Automatic adaption to varying light conditions
Dark current: Accurate determination at each measurement cycle
Manual acquisition: Interface software for manual measurement and calibration
Automatic acquisition: Fully autonomous measurement mode for unattended data acquisition
Quick measurements: 20 seconds under bright sunshine 60 seconds in overcast conditions
Stability: Reference system stability check and uncertainty estimates
Simultaneous metadata: Spectrometer Temperature, Outside Temperature, GPS position, GPS time
Data Display: Live assessment of the systems status
Data storage: SD card up to 32 GB (12 months of measurements)
Case: Robust and Waterproof housing based on the 1510 Pelicase
Dimensions: 500 × 300 × 200 mm
Power supply: 12 Volt. From battery and solar panels
Power consumption: Average consumption of 60 Watt. (20/100 Watt, cooling on/o)
Energy saver: Day/night switch for energy saving
Interfaces: RS232 via cable and wireless – SDI-12