Hendrik Wade Bode contributed to electrical engineering and systems design. He received patents for transmission networks, transformer systems, electrical wave amplification, broadband amplifiers, and artillery computing. However, his name is mainly remembered because of Bode plot used in impedance analysis named after him.

Hendrik Wade Bode was born 24 December 1905, in Madison, Wisconsin. He attended High School in Urbana, Illinois, and Normal School in Tempe, Arizona. Continuing his education, he received his B.A. Degree in 1924 from Ohio State University and his M.A. Degree from the same institution in 1926. During this time, he was a teaching assistant for one year. Coming immediately to Bell Telephone Laboratories, he began his career with electric filter and equalizer design. Three years later, in 1929, he transferred to the Mathematical Research Group, where he specialized in research pertaining to electrical networks theory and to its application to long distance communication facilities. While employed at Bell Laboratories, he attended Columbia University Graduate School, and received the Ph.D. Degree in 1935. H.W. Bode in 1938 used the magnitude and phase frequency response plots of a complex function. He investigated closed-loop stability using the notions of gain and phase margin.
 

The Bode diagram is also often used for presentation of impedance spectra. The Bode plot of the impedance for the electric circuit of Figure 1 is shown in Figure 2. The Bode plot explicitly shows frequency information. The impedance is plotted with log frequency on the x-axis and both the absolute value of the impedance, |Z|, and phase-shift on the y-axis. Simple electronic circuit with one time constant Figure 1

Figure 2

With the outbreak of World War II, Bode turned to the development of electronic fire control devices. The methods of analysis and design that he developed proved highly applicable to the related field of servomechanisms during World War II. Bode characterized this convergence of control and communications as having been a "sort of shotgun marriage." In recognition of his contributions in this field, he was awarded the Presidential Certificate of Merit (in 1948) for his work in the field of fire control under the NDRC of the OSRD.

Bode's work in electric filters and equalizers led to broader aspects of communication transmission, resulting in the publication in 1945 of his book Network Analysis and Feedback Amplifier Design, which is considered a classic in its field. He has been granted 25 patents in electrical engineering and systems design, including patents for transmission networks, transformer systems, electrical wave amplification, broadband amplifiers, and artillery computing.

Following World War II, he worked in part on military problems, including those in missile systems, and in part on modern communication theory. He has been involved in the work of a number of government committees, and has written many scientific and technical articles for publication. In 1944, Bode was placed in charge of the Mathematics Research Group at Bell Laboratories, and in 1952 became Director of Mathematical Research. In 1955 he was appointed Director of Research in the Physical Sciences, and in 1958 assumed the responsibilities of Vice-President in charge of one of two vice-presidential areas devoted to military development.

In the mid 1960s, Hendrik Bode wrote in an essay on Basic Research and National Goals, "It is not necessarily true that an increase of [fundamental] research by itself would lead to a significant increase in... beneficial applications. The outcome would depend primarily on the overall structure. The primary problem confronting the country, then, is that of maintaining a scientific and technological establishment that works in a coherent and effective way."

Bode retired from Bell Telephone Laboratories in October 1967, at the age of 61, after 41 years service in a distinguished career. He was immediately elected Gordon McKay Professor of Systems Engineering at Harvard University. In his new career, Bode was teaching and directing graduate student research, and conducting a seminar on the planning and conducting of engineering and development programs. He was collecting information on military projects particularly with respect to research in areas where there are difficulties concerned with decision making, and is also studying the relationship of technology to social problems.
 

NACA's Special Committee on Space Technology (H.W. Bode is 4th from left, see the enlarged fragment)

Bode was a member or fellow of a number of scientific and engineering societies, including Fellow, IEEE; Fellow, American Physical Society; Member, American Mathematical Society; Member, Society for Industrial and Applied Mathematics; and Fellow, American Academy of Arts and Sciences. He has also achieved further distinction by being elected to the National Academy of Sciences, and the National Academy of Engineering.

While Bode's chief interests have been science and engineering, be has found time to pursue two major hobbies. One of these is reading, in which he is known as an avid reader on a wide variety of subjects. And, as frequently happens, persons from the Middle West and Southwestern parts of the United States develop an interest in boating when they come to the Eastern coast. Bode engaged in sail-boating on Long Island Sound during his early career in the New York area, and after World War II, he acquired a converted LCT, which he operated on the upper reaches of the Chesapeake Bay adjacent to the Eastern Shore of Maryland. He was also a "do-it-your-selfer," interested particularly in gardening around his home. Bode's wife was the former Barbara Poore. They had two children, Katherine Anne Bode and Beatrice Anne Hathaway Bode.

Hendrik Wade Bode died on June 21, 1982.