We report the fluctuation-induced conductivity of Ca doped Y 1 Ba 2 Ca 3 O 7 - δ samples. The analysis has been done with partial substitution of Ca(II) in place of Y(III). The Ca contents are 0.02, 0.05, 0.1 and 0.2. In each case excess conductivity has been analysed and we tried to make a fit with the Aslamazov-Larkin and Lawrence-Doniach equations. It is observed that our data fit well with the 3D AL equation and a cross-over from 2D to 3D has been found in our samples. For the first time we have employed this transition to estimate the Josephson coupling strength in the multiperiodic layered defect superconductor. This interlayer coupling strength J that controls the transition decreases with increase in Ca content. The variation of the Josephson coupling strength and T c with x have been discussed. The Ginzburg-Landau coherence lengths ξ c (0) for all cases have also been calculated and plotted.