Miller was born in Hanover, Pennsylvania. In 1904 he graduated from Yale University, in 1907 he received an M.A. from Yale, and in 1915 he received his Ph.D. in physics from Yale. From 1907-1919 he was a physicist with the National Bureau of Standards, then a radio engineer at the United States Navy's Radio Laboratory (1919–1923) in Anacostia, District of Columbia, and subsequently at the Naval Research Laboratory (NRL). From 1925-1936 he led radio receiver research at the Atwater Kent Manufacturing Company, Philadelphia, and from 1936-1940 was assistant head of the research laboratory for the RCA Radiotron Company. In 1940 he returned to NRL where he became superintendent of Radio I Division (1945), associate director of research (1951), and scientific research administrator (1952). He married Frances Riley; the couple had seven children — two girls and five boys.
Miller was awarded the Distinguished Civilian Service Award in 1945 for "initiation of the development of a new flexible radio-frequency cable urgently needed in radio and radar equipment which solved a desperate material shortage in the United States during World War II," and the IRE Medal of Honor in 1953 for "his pioneering contributions to our basic knowledge of electron tube theory, of radio instruments and measurements, and of crystal controlled oscillators."
^Although Miller's obituary in the New York Times stated that he was born on June 21, 1882, church records in Hanover, Penn. (the place of his birth) and Miller's World War I draft registration card (which he signed) stated that he was born on June 22, 1882.