An overview of computational methods for modeling the low-frequency electromagnetic characteristics of antennas is given. Presented first is a brief analytical background that forms the basis for numerically solving low-frequency antenna problems using the method of moments. Next discussed are extensions to modeling perfectly conducting objects in free space, followed by a consideration of some computational issues that affect model accuracy, efficiency, and utility. A variety of representative applications is given to illustrate various aspects of modeling and capabilities that are currently available. A fairly extensive bibliography is included.>

The purpose is to illustrate the computational complexity of modeling large (in wavelengths) electromagnetic problems and to suggest some ways by which the computational requirements can be reduced. The author indicates that, despite the dramatic increase of 106 in throughput that has occurred between the UNIVAC-1 and the current CRAY-2, the impact on the ability to handle computations at ten times the original (temporal) frequency has shown only marginal improvements. This is because the required floating-point operation (FLOP) count for integral-equation (IE) and differential-equation (DE) models grows with frequency. f, as f/sup x/, where 3>