Laboratory evaluation of the GreenSeeker^(TM) handheld optical sensor to variations in orientation and height above canopy  

作　　者：Daniel E Martin Juan D Lopez Jr Yubin Lan 

机构地区：[1]USDA-ARS,Southern Plains Agricultural Research Center,College Station,Texas 77845,USA

出　　处：《International Journal of Agricultural and Biological Engineering》2012年第1期43-47,共5页国际农业与生物工程学报（英文）

摘　　要：Handheld optical sensors recently have been introduced to the agricultural market.These handheld sensors are able to provide operators with Normalized Difference Vegetative Index(NDVI)data when cloud cover prevents acquisition of satellite or aerial images.This research addressed the sensitivity of the GreenSeeker handheld optical sensor to changes in orientation and height above a ryegrass canopy.Planter boxes were oriented both parallel and perpendicular to the light beam from the sensor head and heights of 30.5 cm(12”),61.0 cm(24”),91.5 cm(36”),122 cm(48”)and 152 cm(60”)were tested.Results indicated that the sensor was highly sensitive(P<0.0001)to both height above canopy and orientation of the sensor relative to the target.Operators should follow manufacturer’s recommendations on operating height range of 81-122 cm and orient the sensor head in-line with the target to obtain maximum signal response.

关 键 词：remote sensing NDVI GreenSeeker handheld optical sensor spectral reflectance 

分 类 号：TP2[自动化与计算机技术—检测技术与自动化装置]