A study of modulation schemes and error correction mechanism in a Wireless underground sensor network

A cluster of sensor nodes can form a wireless underground sensor network (WUSN) deployed beneath the earth's surface for applications, like smart irrigation in agriculture field. Comparing with a free space communication, the channel in this context can also cause various signal propagation effects, which needs to be modelled and analysed, including the small-scale effects like Rayleigh fading. Different modulation schemes have been analysed to select an optimum one and an Error correction mechanism has been simulated with BPSK modulation for the performance evaluation in an AWGN channel. In this paper, the communication channel, that is, the soil medium, has been considered as a linear time varying filter in which the filter coefficients are strongly correlated, which will give the channel state information.