Remembering Ernest J. Wilkinson
By Paul Kruczkowski, Editor
Last month, the RF engineering industry lost one of its luminaries with the passing of Ernest J. Wilkinson Jr. He is best known for inventing the power divider circuit that bears his name, which has been used by countless RF engineers who followed him.
Wilkinson was born on May 23, 1927, in Fall River, MA, where he was raised. He later joined the U.S. Navy and served on the USS Pocono during World War II. Following the war, Wilkinson earned his BSEE Northeastern University and his Master of Science degree at Stanford University. His professional career included work on weapons development, advanced radar and communications equipment, and satellite communications systems.
Wilkinson published many technical papers and articles on antennas and microwave components, including his seminal work, "An N-way Hybrid Power Divider", which appeared in the 1960 IRE Transactions on Microwave Theory and Techniques. The paper described a new power divider structure that would eventually become known as the Wilkinson power divider. The design was based on quarter-wave transformers that match the input (common) port to the output (split) ports of the circuit. By adding resistors between the output (split) ports, Wilkinson was able to achieve isolation between the output (split) ports while maintaining a matched condition on all ports.
Wilkinson was also granted several U.S. patents on a circularly polarized slot antenna, an eight-way coaxial power divider, satellite antenna autotrack system, and a dual polarized cylindrical reflector antenna system, to name a few. His work on these and other designed have been referenced in countless other patents.
As an engineer in the broadcast TV transmitter industry, I was one of many impacted by Wilkinson's technical contributions through my utilization of his namesake splitter to both split and combine amplitude and phase matched amplifiers. His achievements in RF engineering were many, he greatly influenced those who followed him, and his name will live on forever in RF engineering history.