The various embodiments provide systems, devices, and methods which include an acoustic tag configured to transmit an acoustic signal through a contact medium that may be received by an acoustic modem, with the acoustic signal configured to transmit information. An opening can be formed through the body along a second longitudinal axis. Preferably, each of two resistance mediums connects one side of the platform with one side of the frame. In a state 3, the mobile station 21 requests only the second base station 12 to transmit the data and communicates with the second base station 12.