Purpose:NDVI sensors (also known as canopy normalized vegetation index) are dual band radiation detectors that can monitor canopy normalized vegetation index (NDVI) for long-term continuous positioning near the ground. NDVI is sensitive to the response of green vegetation and is often used to study the growth status of vegetation. The manufacturing process of NDVI measuring instrument sensors is exquisite, and the hemispherical diffuser can promote self-cleaning to minimize errors caused by dust and debris. Durable and sturdy, capable of working normally in various harsh weather conditions; It is compact in size and easy to install; High cost-effectiveness, can be deployed in multiple locations.
The difference between the reflectance of the canopy at near-infrared wavelength (810nm) and the reflectance of red wavelength (650nm) is calculated as the sum of the two. Therefore, it is necessary to install both upward and downward sensors simultaneously to monitor the reflectance of the canopy at these two wavelengths.
characteristic:
·Durable self-cleaning housing, dome shaped sensor head (diffuser and body) helps reduce dew and rain;
·Traceability calibration;
·Shielded twisted pair cable with sheath, possessing high water resistance, UV stability, and flexibility under cold conditions;
Spectral Response
Technical parameters:
Probe body | |
Band range |
Red light: 650nm ± 10nm FWHM Near infrared: 810nm ± 10nm FWHM |
Calibration uncertainty |
±5% |
Measurement repeatability |
Less than 1% |
drift |
Less than 2% per year |
response time |
Number: less than 0.6S Simulation: less than 1mS |
viewing angle |
180 degrees (upward) and 40 degrees (downward) |
cosine response |
± 2 % at 45˚; ± 5% at 75 ° zenith angle |
Temperature response |
Less than 0.1% per ° C |
Shell material |
Anodized aluminum body with acrylic diffuser |
work environment |
-40 ~ 70℃,0~100%RH |
INPUT VOLTAGE |
5.5-24VDC excitation power supply |
output |
Digital output: SDI-12 Analog output sensitivity: (up: 5mV/W.m-2 red light, 6.67mV/W.m-2 near-infrared) (Down: 10mV/W.m-2 red light, 6.67mV/W.m-2 near-infrared) Analog output range: (up: 18.5mV red light, 26mV near-infrared) (Down: 20mV red light, 20mV near-infrared) |
calibration factor |
Digital output: Built in firmware Analog output: (Upward: 0.2mV/W.m-2 red light, 0.15mV/W.m-2 near-infrared) (Down: 0.1mV/W.m-2 red light, 0.15mV/W.m-2 near-infrared) |
size |
Diameter: 30.5mm, height: 36.6mm (upward) Diameter: 23.5mm, height: 40mm (downward) |
Note: Analog signals can be connected to AT-100 Bluetooth recorders.