Introduction to the Classic Paper

Raymond Alphonsus Heising (Fig. 1), born in 1888, contributed to the development of radio by demonstrating (in 1923, at the age of 35) the first transatlantic radio communication using single-sideband modulation. Heising’s contribution built on the work of a small number of prominent pioneers in the development of radio communication [1]. The German physicist Heinrich Hertz, in a series of spectacular experiments (1885–1889), confirmed the little appreciated or understood electromagnetic theory of James Clerk Maxwell (1864) by demonstrating electromagnetic waves and confirming their finite velocity. Hertz showed no interest in the practical applications of his discoveries. It was Guglielmo Marconi, an Italian working in England, who was determined to create a wireless telegraphy system and who received faint signals in Newfoundland transmitted from Poldhu, Cornwall (1901). Marconi did not realize that the success of his experiment depended on the reflection of the ionosphere, which was not discovered until 1924. Had he carefully analyzed the propagation, he probably would have concluded that his objective was not feasible! Both Hertz and Marconi used a noise-like signal generated by a spark gap and filtered by the resonance of an antenna system and a receiving antenna tuned by a similar resonance with no amplification. Marconi had complete faith in the telegraph and did not believe it compelling to transmit speech or music by radio. It was Reginald Fessenden, a Canadian working in the United States, who pursued a vision of transmitting “words without wires” by continuous wave (CW) modulation. His transmitter, patented in 1901 but not demonstrated until 1906, consisted of a high-frequency alternator (rotating machine) connected to an antenna system with a series carbon microphone (technology borrowed from the telephone). On Christmas Eve,