Radio Research Laboratory
Encyclopedia
The Radio Research Laboratory (RRL), located on the campus of Harvard University
was an 800-person secret research laboratory during World War II
. Under the U.S. Office of Scientific Research and Development
(OSRD), it was a spinoff of the Radiation Laboratory
(Rad Lab) at MIT, and set up to develop electronic countermeasures
to enemy radars and communications, as well as electronic counter-countermeasures (ECCM) to circumvent enemy ECM. The RRL was directed by Frederick E. Terman and operated between 1941 and 1945.
The RRL was engaged in both analysis and hardware development. They made significant contributions to the basic understanding of methods, theories, and circuits at very-high and ultra-high frequencies for radio systems, particularly in signals intelligence gear and statistical communications techniques. However, unlike the Rad Lab, the RRL never released significant details on its accomplishments; ECM and ECCM have always been closely guarded secrets by all nations.
The RRL conducted considerable work on chaff, light-weight aluminum strips dropped in clouds from aircraft to confuse enemy radars. Fred L. Whipple, an astronomer, made detailed analytical studies of this and devised a formula giving radar cross-section at a given wavelength per kilogram of chaff.
An example of RRL hardware development was Tuba, (aka 'Project Tuba') a giant ECM system generating continuous 80-kW signals in the range of 300-600 MHz to jam German Lichienstein radars. The power tube (called Resatron) for Tuba was developed at the RRL by David H. Shone and Lauritsen C. Marshall. Tuba used a horn antenna
built of mesh wire 150 feet long and driven through 22- by 6- inch waveguides, possibly the largest ever built. Tuba was placed in operation in mid-1944 on the south coast of England. The radiated energy was such that it lighted fluorescent bulbs a mile away and jammed radars throughout Europe.
The RRL staff did document some of the general theory that they developed. After the war, this was released in a two-volume publication Very High-Frequency Techniques, edited by Herbert J. Reich (McGraw-Hill, 1947).
Harvard University
Harvard University is a private Ivy League university located in Cambridge, Massachusetts, United States, established in 1636 by the Massachusetts legislature. Harvard is the oldest institution of higher learning in the United States and the first corporation chartered in the country...
was an 800-person secret research laboratory during World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
. Under the U.S. Office of Scientific Research and Development
Office of Scientific Research and Development
The Office of Scientific Research and Development was an agency of the United States federal government created to coordinate scientific research for military purposes during World War II. Arrangements were made for its creation during May 1941, and it was created formally by on June 28, 1941...
(OSRD), it was a spinoff of the Radiation Laboratory
Radiation Laboratory
The Radiation Laboratory, commonly called the Rad Lab, was located at the Massachusetts Institute of Technology in Cambridge, Massachusetts and functioned from October 1940 until December 31, 1945...
(Rad Lab) at MIT, and set up to develop electronic countermeasures
Electronic countermeasures
An electronic countermeasure is an electrical or electronic device designed to trick or deceive radar, sonar or other detection systems, like infrared or lasers. It may be used both offensively and defensively to deny targeting information to an enemy...
to enemy radars and communications, as well as electronic counter-countermeasures (ECCM) to circumvent enemy ECM. The RRL was directed by Frederick E. Terman and operated between 1941 and 1945.
The RRL was engaged in both analysis and hardware development. They made significant contributions to the basic understanding of methods, theories, and circuits at very-high and ultra-high frequencies for radio systems, particularly in signals intelligence gear and statistical communications techniques. However, unlike the Rad Lab, the RRL never released significant details on its accomplishments; ECM and ECCM have always been closely guarded secrets by all nations.
The RRL conducted considerable work on chaff, light-weight aluminum strips dropped in clouds from aircraft to confuse enemy radars. Fred L. Whipple, an astronomer, made detailed analytical studies of this and devised a formula giving radar cross-section at a given wavelength per kilogram of chaff.
An example of RRL hardware development was Tuba, (aka 'Project Tuba') a giant ECM system generating continuous 80-kW signals in the range of 300-600 MHz to jam German Lichienstein radars. The power tube (called Resatron) for Tuba was developed at the RRL by David H. Shone and Lauritsen C. Marshall. Tuba used a horn antenna
Horn antenna
A horn antenna or microwave horn is an antenna that consists of a flaring metal waveguide shaped like a horn to direct the radio waves. Horns are widely used as antennas at UHF and microwave frequencies, above 300 MHz...
built of mesh wire 150 feet long and driven through 22- by 6- inch waveguides, possibly the largest ever built. Tuba was placed in operation in mid-1944 on the south coast of England. The radiated energy was such that it lighted fluorescent bulbs a mile away and jammed radars throughout Europe.
The RRL staff did document some of the general theory that they developed. After the war, this was released in a two-volume publication Very High-Frequency Techniques, edited by Herbert J. Reich (McGraw-Hill, 1947).