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For deploying a wireless sensor network system and studying the channel characteristics in tomato greenhouse, relationships among radio frequency signal propagation characteristics and communication distances, antenna heights, transmission paths were studied with a 2.4 GHz carrier frequency for configuring wireless sensor network in a tomato greenhouse. The results showed that the attenuation of the received signal strength caused by communication distance accorded with a logarithmic model. When the height was fixed, the strength index of received signal tended to decrease and the packet loss rate fluctuated as the distance of transmitter to receiver increased, which was an overall increasing trend. It was the best to place the antennas at a column of central location in greenhouse, in the top of the tomato or above of it, followed at higher place above 1.5 m. The regression analysis results demonstrated that there was a quadratic relationship between the regression parameter A and the antenna height, and there was also a quadratic regression equation between the environmental factor n and antenna height. Besides, a model used for calculating the received signal strength of 2.4 GHz transmitting through tomato greenhouse was constructed. Validation results showed that the model could better predict the received signal strength at different distance point at different height. This research can provide a reference for WSNs application.