AN EXAMINATION OF SHORT-RANGE RADAR FOR DETECTING TREE FOLIAGE ON AN ORCHARD SPRAYER
This paper provides information derived from a study of Short-Range RADAR as a sensor technology for detecting tree foliage in control of an air-blast orchard sprayer. The motivation for the research was a desire to overcome the shortcomings of ultrasonic ranging sensors currently being used in this application. The methodology for this investigation involved analysis of the advantages and constraints of currently available short-range RADAR technology. This led to a focus on Frequency Modulated Continuous Wave (FMCW) systems and specifically on the issues of received-signal processing and transmit-signal sweep linearity. The most valuable outcome of this study was the formulation of a computationally simple method for deriving range information from the sampled baseband receive signal. A second valuable outcome involved realization of a technique for achieving a fast linear sweep from a Phase-Locked-Loop (PLL) transmit frequency generator. These results were demonstrated through the development of a representative experimental system. A functional sensor based on the results of this study is currently under development.
Jarnagin, R.C. (2009). AN EXAMINATION OF SHORT-RANGE RADAR FOR DETECTING TREE FOLIAGE ON AN ORCHARD SPRAYER. Acta Hortic. 824, 85-90
orchard sprayer, short-range RADAR, FMCW