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The wind field parameters on rice canopy which formed by rotor airflow are significantly difference among different structure of unmanned helicopter. There are direct influence among the seed setting rate, operating efficiency, and the parameters of wind field on rice canopy. To explore the optimization parameters when the uniaxial single-rotor electric unmanned helicopter (USREUH) conducted supplementary pollination, orthogonal tests of three factors (including flight operating load, altitude and speed) and three levels was developed to measure the wind field which produced by USREUH in this study. The mass of tested USREUH is 9.3 kg, its rotor diameter is 2 m, and its maximum payload is 15 kg. The measured parameters of wind field included the following: wind speed at X direction (parallel to the direction of flight heading), Y direction (perpendicular to the direction of flight heading), and Z direction (the vertical direction), and also the battery's voltage drop at each takeoff and landing of USREUH to estimate its economy. The wind field parameters of the USREUH were measured by a wireless wind speed sensor network measurement system (WWSSN), which consists of several wireless wind speed sensors (WWSS), a flight global position system (FGPS), and an intelligent control focus node (ICFN). The WWSSN is a star topology, which can realize multi-point, multi-direction, mobile, and real-time measurement for wind field parameters on rice canopy, and also can record the pose information of the USREUH when the supplementary pollination is conducted. In order to reduce the affect from natural wind speed, serveral treatment rules about natural wind speed were adopted before wind field data analysis. The test results showed that: the maximum width of wind field produced by USREUH (peak wind speed >1 m/s at Y direction) was reached 8.1 m, it was indicated that this model of USREUH could meet the basic needs of supplementary pollination of hybrid rice under the designed test conditions. The peak wind speed which produced by USREUH was mainly affected by the following factors: flight operating load, altitude and speed. The lower altitude and flight speed, along with the increasing payload, it the higher peak wind speed was expected. Considering the width of wind field and battery electricity consumption, the order of the three influence factors is flight speed, takeoff weight, and flight height. And the optimal operation parameters for supplementary pollination in hybrid rice breeding are flight speed of 1.56 m/s, takeoff weight of 14.05 kg, and flight height of 1.93 m, respectively. The conclusions provide the important reference for the studies of operation parameters optimization based on any other kinds of USREUH, which are useful to the form of specifications for supplementary pollination in hybrid rice breeding using USREUH. [ABSTRACT FROM AUTHOR]