Wireless sensor network technology allows real‐time soil water content monitoring with a high spatial and temporal resolution for observing hydrological processes in small watersheds. The novel wireless soil water content network SoilNet uses the low‐cost ZigBee radio network for communication and a hybrid topology with a mixture of underground end devices each wired to several soil sensors and aboveground router devices. Data communication between the end and router devices occurs partially through the soil, and this causes concerns with respect to the feasibility of data communication due to signal attenuation by the soil. In this study, we determined the impact of soil depth, soil water content, and soil electrical conductivity on the signal transmission strength of SoilNet. In a first step, we developed a laboratory experimental setup to measure the impact of soil water content and bulk electrical conductivity on signal transmission strength. The laboratory data were then used to validate a semi‐empirical model that simulates signal attenuation due to soil adsorption and reflection and transmission at the soil boundaries. With the validated model, it was possible to show that in the case of a soil layer of 5 cm, sufficient power will remain to ensure data communication over longer distances for most soil conditions. These calculations are fairly simplified and should be considered as a first approximation of the impact of attenuation. In actual field situations, signal transmission may be more complex. Therefore, a field evaluation of signal attenuation is a crucial next step.

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One sector or approximately one-quarter betatron osciUat ion away from Am-1, the beam has reached its maximum deviation of 1 em, and gasses by the septum of MX-2. RIX-I L an &-cored puked magnct whose field Btrength is 4 kilogause, PWT-2 provides an additional bending of approximately 17' to the beam. It is this rather Bevsre bending, necessary to extract the beam, which pose8 the greatest danger of aberration~i. Upon leavina M X-2 the beam proceeds across the pole of the next negative magnet which further deflects the beam outward. At this point it passes out of the main accelerator vacuum tank. In order to nxiss the next magnet back leg, further bending is required. Because of the small amount of space available, another pulsed magnet, MX-3,' is employed. MX-3 is a 5 tilogauss picture frame ironcored magnet which bends the beam 24'. MX-4 and PAX-6 a r e dc 5 kilogauss magnets with'adjustable &* entrance edge angles, With appropriate choice of edge angles, spacings and bendhg angles of NIX-4 and fMX-5, particles initially on dfffereat equilibrium orbits of the accelerator will all Ue on a single line when / leaving MX-5. MX-4 is placed 80 cm f m m MX-3 and bends the beam 30°, Its entrance edge angle is lo (radially focusing). M X-5 is placed 1 meter from 1W[-4 and bends the beam 45'. Its entrance edge angle is 0.3O (radially focusing), The small entrance edge angles help to minimbe \ the aberrations in the system. At several placoe in, the oystem electrostatic induction electrodes are provided to detect tho, position of the center of mass of the beam.