Underwater network cardinality estimation using cross-correlation: Effect of unequal sensor spacing

Network cardinality is very crucial factor to ensure proper functionality of a network. Because of inimitable properties of underwater environment (such as strong background noise, unavoidable capture effect, limited bandwidth, long propagation delay, high path loss, node mobility etc.) network cardinality estimation of underwater environment could be a severe challenge utilizing the subsisting protocol based techniques. For this reason, a cross-correlation based statistical signal processing technique has been investigated utilizing Gaussian signals received at multiple sensors. Equidistant sensors have been used for estimation in three-sensor case of this technique. But, due to the hazardous condition of underwater environment, equal sensor spacing may not be possible in practical cases. To address this issue, effect of unequal sensor spacing on estimation results is analyzed in this paper.