This paper describes the radio propagation measurement campaign in the sugarcane field representing a tall food grass characteristic which is one of the common types in outdoor agriculture environments. The measurement was conducted by using a channel sounder having a bandwidth of 45.6 MHz at 2.45 GHz with the aim at investigating the propagation channel characteristics which are useful in deploying of wireless sensor networks in the precision agriculture. By analogy to Ikegami model, the variation of path loss over the relative angles between the plant rows and the line-of-sight direction from the transmitter to the receiver is identified. Utilizing this knowledge, this work justifies the procedure of predicting the path loss at any point in the field by a few measurement efforts. Furthermore, the Rician K-factor and RMS delay spread are investigated in the vegetation depth shorter than 40 m. The result shows that the relationship between the Rician K-factor and its corresponding path loss value in each measurement point can be fitted with the log-linear line. This leads to the possibility of predicting K-factor at any points in the field. In addition, since the result of RMS delay spread is independent to the vegetation depth and the density of the plant, it is represented by the statistical model in which the Weibull distribution provides the best representation.
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