Henry Joseph Round was born to Joseph and Gertrude Round on 2 June 1881, and was their eldest child. He grew up in Staffordshire, England. He graduated with honors from the Royal College of Science, which is associated with Imperial College London. After graduation, he joined the the Marconi Company in 1902, right after Marconi's historic transatlantic ra wireless transmission. He was a personal assistant to Marconi. He traveled to the USA to continue his work on radio technologies, such as tuning inductors. He also performed some experiments with transmission paths over land and sea at different times of the day, and leveraging frame antenna for direction finding. He was the first to report observation of electroluminescence from a diode, that lead to the discovery of the light-emitting diode and electro-luminescent wires.
Captain Henry Joseph Round was a prolific innovator and received 117 patents in his lifetime.
As the First World War broke out, in 1914, Round was asked to assist the Military Intelligence. He joined with a rank of Captain. His research in direction finding, with frame antennae, was instrumental in setting up a chain of direction finding stations along the Western Front. These stations proved so successful that another set was installed in England. For all his services during the war, Captain Henry Joseph Round was awarded the Military Cross. After the war Captain Henry Joseph Round returned to civilian life and became involved in radio transmitters and was heavily involved in the first broadcasts made in the United Kingdom. For all his successes, Round was made Chief Engineer at Marconi in 1921, but some years later he decided to set up his own consultancy.
With the Second World War breaking out again in 1939, he was called on to serve the British Intelligence again. This time he was involved in Anti-Submarine Detection Investigation Committee (ASDIC ), which essentially developed the technology behind SONAR.
Round died in August 1966 in a nursing home in Bognor Regis after a short illness.