Professor Spielman joined the Naval Research Laboratory (NRL) in 1971 as a research electronics engineer in the Microwave Techniques Branch and pursued his career at NRL for 17 years. During this period he was promoted to various positions and ultimately to Head of the Microwave Technology Branch in 1984. In this capacity he led a group of 20 researchers investigating a wide range of microwave semiconductor and superconductor devices and related integrated-circuit components. His personal research involved the development of computer-aided electromagnetic solutions to microwave problems. He served in this position until he left to join the Department of Electrical Engineering at Washington University as Professor and Chair in 1987.
Professor Spielman is currently performing research on the synthesis of microwave packaging features through electromagnetic solutions. This work first involves developing mathematical formulations of 3-dimensional, electromagnetic problems involving arbitrarily-configured conductors and dielectrics. This formulation is then reduced to a computationally useful matrix analysis employing the method of moments. This analysis is then cast as an optimization problem by defining a cost function that incorporates specified performance at generalized ports for the configuration. The optimization is performed by computer to effect a "synthesis" of the desired geometry and/or material configuration.
This work has evolved in a new direction to create an area of research called investigative synthesis. This new direction seeks to generate knowledge about the potential of achieving desired performance levels for various categories of applications using entirely new microwave circuit structures that are not amenable to traditional microwave circuit modeling (e.g. using transmission lines and lumped elements) and are, thereby, less intuitive. Knowledge is generated by the following process. New design classes are first characterized by discrete parameters that represent the new class of microwave structures. The performance levels achievable for the new class are interpreted as samples in a design space and are stored in a database. Information in this databased is then interpreted using techniques from statistics, information theory, and population genetics to organize the generated knowledge.
Spielman has held numerous offices in the IEEE, including President of the IEEE Society on Microwave Theory and Techniques (MTT-S) in 1988. He has served as guest editor of various publications, including special issues of the IEEE Proceedings and the IEEE-MTTS Transactions. He is currently serving as the President of the National Electrical Engineering Department Heads Association (NEEDHA). He was recently elected Life Fellow in the IEEE.