A hybrid fourth-order FDTD utilizing a second-order FDTD subgrid

A hybrid method utilizing the second-order accurate in time and fourth-order accurate in space FDTD (2, 4) coupled with the standard second-order accurate both in time and space FDTD (2, 2) on a subgrid is presented. The accuracy of the method is tested by computing the S-parameters of two monopoles mounted on a ground plane and it is found to be very satisfactory. Significant computational savings both in memory and time are accomplished by using this hybrid method.