Curiously, the most direct predecessor that Scholtz identifies to later spread-spectrum developments was a radio control system for a glide bomb developed during World War II not by Germany but by the U.S. Navy with support from the National Bureau of Standards. The parallel between German and U.S. glide-bomb work raises the interesting question of whether the Navy had learned of German glide-bomb development from the Oslo Report or some other espionage source. If so, it has never acknowledged a connection. “One of several secure radio guidance efforts,” Scholtz writes of the U.S. program, “took place at Colonial Radio, predecessor of the Sylvania division at Buffalo, NY. This project was under the direction of [the engineer] Madison Nicholson.”
Nicholson’s team had developed a limited two-hop frequency-hopping system, code-named Janus, to help foil possible jamming of the glide-bomb radio link. “Although the radio link was designed to be covert,” Scholtz notes, “the system could withstand jamming in one of its two frequency bands of operation and still maintain command control.” The Navy glide bomb that eventually emerged, code-named Bat, saw limited use in the Pacific theater late in the war, sinking several Japanese ships and destroying bridges and other targets in Burma.
An important postwar influence on spread-spectrum development was a seminal paper by the mathematician and electrical engineer Claude Shannon, “A Mathematical Theory of Communication,” published in the Bell System Technical Journal in 1948. In his paper, which has been called the founding document of information theory, Shannon showed that a wider spectrum—a wider channel—can carry a given quantity of information more reliably than a narrower channel. An English expert puts it another way. “Shannon’s formula,” he writes, “indicates that a wide-band signal is more robust [than a narrow-band signal] when the channel is noisy and, of course, jamming is just another source of noise.” Another advantage of wider bandwidth compared with narrower, Shannon showed, is that the same volume of data can be sent with a less powerful transmitter. (Shannon coined the term “bit” in his 1948 paper as well.)
In 1955, contemporary with Scibor-Marchocki’s sonobuoy work at Hoffman Laboratories, Madison Nicholson at Sylvania Buffalo initiated work on a radio communications system that Sylvania hoped would be selected for the new nuclear submarines the Navy was developing. Known by the acronym BLADES, the system used frequency-hopping spread spectrum (FH-SS) to overcome the problem of multi-path distortion in long-range communications—that is, distortion caused by a signal bouncing off mountains and other radio-reflective surfaces and arriving at a receiver along several different paths at once.
After several years of testing and improvement, a prototype BLADES was delivered to the Navy in 1962. The prototype was installed on the Mount McKinley, the flagship of the Navy’s amphibious forces during the Cuban missile crisis that October. Scholtz writes that the radio system was “evidently carried into the blockade associated with the Cuban Missile Crisis but was not tested there due to a radio silence order.” The Mount McKinley sailed from the Caribbean to the Mediterranean early in 1963. There, says Scholtz, “intentional jamming was encountered, and BLADES provided the only useful communication link for the McKinley. Thus, BLADES was quite likely the earliest FH-SS communication system to reach an operational state.”
Between 1945 and 1978, the U.S. military and national security agencies developed a number of different secret communication systems based on various forms of spread spectrum. Among these were a secure radioteletype system for the U.S. Army; a remote-control system for the Corporal rocket; radio guidance systems for the Sergeant and Jupiter missiles, abandoned when inertial guidance was chosen instead but transferred over to the U.S. Air Force’s Deep Space Program for telemetry, command, tracking, and ranging; the Phantom radio system developed by General Electric for the Air Force; the Martin Company’s RACEP system that provided secure mobile voice communications for up to seven hundred users; a similar system from Martin called Cherokee; Motorola’s MUTNS tactical navigation system; ITT’s SECRAL missile guidance system; and a half dozen others. In 1978, Scholtz notes, the U.S. National Security Agency declassified and allowed to proceed through the patenting process “scores of patents including at least a dozen on SS techniques.”
Romuald Scibor-Marchocki, having moved to Aerojet-General in the early 1960s, also made further use of spread-spectrum technology as system manager for a surveillance drone. The drone, he writes, “eventually flew over Vietnam.” He personally designed the two-way radio system for the drone, which was implemented digitally rather than in analog form, as previous incarnations of frequency hopping had been. “For the first time, we had the ability to switch frequencies rapidly; thus, we called it ‘spread-spectrum.’ It is the same concept as ‘frequency-hopping,’ only performed much faster…. The radio signal required very little transmitter power and was immune to noise and interference from other drones, which would employ the exact same carrier frequency.” In Scibor-Marchocki’s drone radio design is thus the basis for a solution to a problem that would reemerge with the advent of the cellular phone: allowing many different phones to talk at once by arranging for them to hop in many different sequences, thus staying out of each other’s way.
Since all these developments were secret, Hedy and George remained unaware of them. Their patent expired seventeen years out from its awarding, in 1959. George Antheil, the bad boy of music, expired with his patent that year of a heart attack on 12 February at the age of fifty-eight. His 1945 autobiography, Bad Boy of Music, had been a best seller, and then he had seen his music finally succeed in the years after the war; in 1947 he was counted among the top four most performed American composers, in company with Samuel Barber, Aaron Copland, and George Gershwin.
Antheil had returned to musical drama in the last decade of his life: an opera, Volpone, based on the Ben Jonson play; one-act operas, The Brothers, Venus in Africa, and The Wish; a ballet based on Ernest Hemingway’s short story “The Capital of the World”; a cantata, Cabeza de Vaca; songs, sonatas, and film, television, and radio scores. “It is a wonderful feeling,” he wrote to his fellow composer Kurt Weill, “to once more, in my imagination at least, be living back in the theater. It is ‘home.’” George and Boski had remained together and close in their intimate, complicated marriage; when George died, in New York City, he left behind not only Boski and Peter but also an illegitimate six-month-old son.
Virgil Thomson’s review of Antheil’s Fourth Symphony, first performed in 1944, catches something of Antheil’s brash character as well as the spirit of his music:
There is everything in it—military band music, waltzes, sentimental ditties, a Red Army song, a fugue, eccentric dancing—every kind of joke, acrobatic turn, patriotic reference and glamorous monstrosity. It is bright, hard, noisy, busy, bumptious, efficient and incredibly real. It is “Columbia, the Gem of the Ocean” orchestrated in red, white, and blue, with three cheers for the same every five minutes and plenty of pink lemonade. By moments it is thin of texture, but at its best and busiest it makes a hubbub like a live crowd and five military bands. And its tunes can all be remembered.