A method of analysis for coupled cylindrical striplines filled with multilayered dielectrics is presented that uses a variational technique in the space domain. Coupled-mode analysis is presented for the case of a pair of coupled circular arc strips arbitrarily located between cylindrical ground planes filled with multilayered dielectrics. An even and odd-mode approach is used for the analysis of shielded cylindrically curved edge-coupled pairs of broadside parallel strips (broadside, edge-coupled cylindrical striplines). The effect of environmental changes on an otherwise planar structure is also studied by extending the present analysis to cylindrically warped coupled striplines. >