S [235]. As an example, when the soil moisture content material Ziritaxestat Autophagy increases from 9.5 to 37.3 , the communication distance of sensor nodes decreases by 70 , and also the node burial depth must reduce from 35 cm to 15 cm. For AG2UG, the signal transmission distance increases by 3 occasions, although for UG2AG, the signal transmission distance only increases by 0.four instances [26]. The maximum transmission distance of UG2UG is 40 m, which primarily depends upon the soil sort. UG2AG can transmit 10000 m [27], and WUSN using a radio frequency of 433 MHz is feasible in agricultural applications [28]. The parameters which are critical to analyze the good quality of soils consist of soil bulk density, soil macro and micronutrients, soil organic matter, pH level, soil water prospective, pesticides, pathogens, and temperature [29,30]. In the transmission of WUSN node signals in underground soil, the signal strength is affected by the joint influence of multiple factors [31,32]. Amongst them, soil moisture content material, node burial depth, soil compactness, and horizontal distance involving nodes tremendously lower WUSN node signal intensity. Thus, a mathematical model between signal strength and multiple soil factors is expected to evaluate the transmission traits of WUSN node signals inside the soil medium. This perform focuses on revealing WUSN transmission rules in soil medium. The goal of this study should be to (i) set up a soil test platform inside the laboratory to investigate the received signal intensity of WUSN nodes under various circumstances of soil moisture content material, node burial depth, soil compactness, soil temperature, soil acidity and alkalinity, and horizontal distance between nodes; (ii) receive the critical elements affecting WUSN node signal transmission in soil medium; (iii) establish a mathematical model among the received signal intensity and critical influencing factors, and take this model because the attenuation model of the WUSN node signal in soil medium. two. Components and Strategies This section describes components and methods relevant to this study, including study web site and test 8-Bromo-cGMP Calcium Channel design, WUSN nodes, and soil test platform for node signal transmission tests. two.1. Study Site and Experiment Style The study web site is situated in Yangling District, Xianyang City, Shaanxi Province (108 07 E, 34 28 N, altitude 43563 m). At this web page, the annual precipitation is 635.1 to 663.9 mm, and also the typical annual temperature is 12.9 C. It belongs towards the warm temperate monsoon sub-humid climate. The soil sort is typical Lou soil inside the Guanzhong area, as well as the soil is fertile and suitable for the development of a range of crops [33,34]. The experiment settings within this study are as follows. The selection of soil moisture content was 100 ; the depth of nodes was 300 cm; the soil compactness was 0.5.5 kg/cm2 ; the soil acidity and alkalinity was 5; the soil temperature was one hundred C, and the level range amongst nodes was 100 cm. Meanwhile, nine levels were selected for all these six aspects. Within the underground transmission test of WUSN node signals, the WUSN node and sink node were arranged within a soil medium. Considering the experimental things, theRemote Sens. 2021, 13,three oforthogonal test technique was adopted for the test, and also the received signal intensity information from the sink node had been obtained below diverse test conditions. The orthogonal tests are shown in Table A1 in the Appendix A. Within this study, ferrous sulfate and industrial soda ash have been employed to regulate the acidity and alkalinity on the soil. Agil.