Jacqueline Hochheiser, Corporate Communications
Most RF engineers know the names of at least a few individuals whose remarkable contributions have left an indelible mark on society and the history of the RF and microwave industry: James Clerk Maxwell, Guglielmo Marconi, Martin Cooper. Another such figure, although perhaps lesser known, is Mihajlo Pupin, a Serbian-American physicist, inventor, and philanthropist. Pupin’s groundbreaking work in the field of electromagnetism and his relentless pursuit of innovation not only revolutionized telecommunication but also paved the way for modern long-distance communication technology. Beyond his scientific accomplishments, Pupin’s life journey is an inspiring tale of perseverance, resilience, and the pursuit of knowledge.
Early Life and Education
Mihajlo Idvorski Pupin was born on October 9, 1858, in the small Serbian village of Idvor in Austria-Hungary. Growing up in humble circumstances, he faced numerous challenges and limited access to education. In fact, as a boy, he worked in the fields near his home tending to sheep. It was the journey form this modest upbringing to the height of success in his later life that inspired him to write his own autobiography, From Immigrant to Inventor. The book chronicles Pupin’s life and serves as a testament to his unwavering determination. It won a Pulitzer Prize in 1924.
Pupin’s insatiable curiosity and compelled him to overcome the obstacles of his environment. With the support of his family and a relentless drive to learn, Pupin managed to secure a scholarship to study at Columbia University in the United States. There, he graduated with honors and became a U.S. citizen before completing his undergraduate study in 1883. He went on to earn a doctorate in mathematical physics at the University of Berlin in 1889 before returning to Columbia as a professor in the new department of electrical engineering for the rest of his academic career.
At Columbia, Pupin immersed himself in the study of physics, focusing particularly on electromagnetism and the propagation of electromagnetic waves. His studies would eventually lead him to pioneer devices known as loading coils, or sometimes referred to as Pupin’s Coil, used for increasing the range of long-distance telecommunications, which had major impacts on the rise of the RF and microwave industry.
His earliest experiments began with studying x-rays, and specifically their imaging capabilities. Although he was not the first to capture an image with x-rays, he succeeded in significantly reducing the exposure time to capture a clear image from one hour to a few minutes by using a fluoroscopic screen that he placed in front of the film. This was known as short exposure x-ray photography, achieved when an atom is struck by an x-ray and produces secondary x-ray radiation (Britannica, Mihajlo Pupin: Serbian American Physicist).
However, Pupin’s most notable invention was the loading coil, or Pupin Coil, as it is sometimes referred to because he patented the technology. The loading coil serves as an inductor inserted into an electronic circuit, which makes the electrical current flowing through the conductor stronger and more stable. This breakthrough was pivotal in advancements in long-range telecommunications, which would eventually lead to the rise of the cellphone and easy, portable communication accessible world-wide. Pupin’s patent for this technique was later purchased by the American Telephone & Telegraph Company (AT&T) for a large sum.
Legacy and Philanthropy
Aside from his scientific accomplishments, Pupin was an avid philanthropist and continued to advocate for his home country of Serbia after his career took him abroad. In 1914, he formed the “Fund Olimpijada Aleksic-Pupin,” a fund within the Serbian Academy of Sciences and Arts devoted to bolstering education in schools in Old Serbia and Macedonia. Scholarships were also awarded every year on Saint Sava Day. The fund was named after his mother, Olympijada, in honor of all the support she gave him throughout his life. He also later began another fund called the “Mihajlo Pupin Fund” that supported schooling for young people and awarded prizes for exceptional achievements in agriculture.
Mihajlo Pupin lived a unique life, pulling himself up from rags to riches when he immigrated to the United States to attend school at Columbia in 1883. It was through his years of education and the continuation of his studies of the electromagnetic spectrum in his professional tenure that led him to invent the loading coil. Not only did his brilliant work in the scientific field lead to innovations in telecommunications and wireless engineering, but Pupin also embodied the spirit of world citizenship and what it means to contribute to the common good of the advancement of humanity.