| Underground environment is a harsh environment for RF or EM field due to the dynamic changes to the underground environment, high absorption of signal energy and also need for larger antenna. So to overcome this problem magnetic based communication was proposed which overcomes the problem of the underground environment, since the magnetic induction doesn't rely on dielectric constant but on magnetic permeability which is constant for most of the times in underground environment. This magnetic induction based technique will have tremendous use for underground sensor network. In this work we try to model the magnetic induction channel model and try to evaluate the model. To evaluate an actual underground environment is built and the designed magnetic induction coils are placed inside the underground environment and evaluated. The parameters which were evaluated are path loss and bandwidth, since these two are important for communication purpose. The test bed is created by filling sand in the tank and placing tubes in-between for the coils to be placed, to provide varying underground condition we varied the volumetric water content. The results show that magnetic induction based communication remains stable and reliable even when there is change in underground environment but in Electromagnetic magnetic waves there is more absorption when VWC percentage is increased. Also the result proves that the theoretical modeling is almost accurate in modeling the magnetic induction based communication. |
