A method of moments model for VHF propagation

Site specific VHF propagation models remain a subject of continuing interest. A number of approximate methods exist and have been applied successfully in specific cases, but the limitations of the approximations of these models remain unclear. A numerically exact model based on the banded matrix iterative approach (BMIA) to the method of moments is presented which enables the solution of practical propagation problems. Although this model remains computationally complex, use of the iterative method along with parallel computing techniques enables large scale propagation problems to be solved within reasonable amounts of computational time. A typical VHF propagation problem involves predicting the power measured by a receiver as a function of altitude at a given distance away from a like polarised transmitter and above an inhomogeneous terrain profile.