Development of soil moisture content measuring instrument based on GPS position.

In accordance with the requirement of water-saving irrigation in preci sion agriculture, an instrument was developed for measuring soil moisture conten t and its position. The instrument consists of a single-chip microcomputer, a G P S receiver, a SWR2 moisture sensor, a keyboard, a LCD display and the RS-232C c o mmunication interface. The method of acquiring and processing of GPS data, outpu t-characteristics of moisture sensor, and the software were also described. Tes t ing data were processed by ARCVIEW, and the distribution map of soil moisture wo uld provide a scientific basis for precision irrigation.