Abstract: A radio signal emitting node (25, 38) is configured to emit a radio signal when buried in soil (10). The node (25, 38) comprises an antenna (20, 39), an integrated electronic circuit (22) electrically connected to the antenna (20, 39) using a feed line (15, 17, 18), and at least one sensor (30) for generating measurement data (31). The integrated circuit (22) is configured to operate the antenna (20, 39) to emit the radio signal containing the measurement data (31) periodically or upon receiving a wireless request (32). The radio signal emitting node (25, 38) is configured to allow a surrounding medium of the soil (10) to influence the near field of the antenna (20, 39) when the node (25, 38) is buried in soil (10) and to decrease or prevent the radio signal emission in case the influence of the surrounding medium onto the near field is withdrawn.