Efficient Integration of Magnetic Positioning and Stable Communications

A promising integration method for high-precision positioning and stable communications by utilizing magnetic induction signals is proposed. In-phase and quadrature components are assigned to the positioning and communications, respectively. A pilot signal is used for identification of the in-phase and quadrature components, which leads to mutual interference of the two components caused by carrier phase synchronization error. Simulation and experiment confirm that the mutual interference and signal-to-noise ratio (SNR) loss are acceptable in our proposed scheme, i.e., the interference is weak and the SNR loss is about 1.6 dB as the carrier phase synchronization error less than
${5^\circ }$
. For instance, it is demonstrated that the root-mean-square error of positioning is less than 1.5 m and the transmission rate of communications is about 3000 bits per second when the distance is about 150 m, which is practical for applications such as the magnetic navigation, as well as compressed voice and message communications underground or underwater.