6:00 PM, Wednesday, 25 August
Early Phased Array Development at Lincoln Laboratory (circa 1958-1968)
Bill Delaney, MIT Lincoln Laboratory
Lincoln’s developments in electronically-steered array antennas began in earnest about 1958. The challenge was the forthcoming need for powerful wide-angle-scanning radars for satellite detection and tracking. The Space Age had just started a year earlier with the launch of Sputnik. The Soviet Union was also launching long-range ballistic missiles and missile defense would demand rapid movement of the antenna beam for surveillance and fire-control.
A small group at Lincoln Laboratory formed around a visionary individual, John Allen, to pursue this immature technology. John’s goal was “National” in scope; he wanted to make electronically-steered arrays a practical option for the defense/military user. The Lincoln program would have to foster tight coupling to the industrial teams, labs and military users around the nation who were also pursuing this technology.
This talk will describe the technology situation in 1958; it was woefully inadequate to the job such that many technical people considered the vision of an affordable, high-powered 5000 element array with all elements acting reliably and in complete phase-coherence as an “impossible dream”. Of course, in the land of the Red Sox, impossible dreams do come true and in 1968 the FPS-85 space surveillance radar went on the air at Eglin Air Force Base with 30 Megawatts of peak power and 5000 elements at UHF. It is still on the air today!
Examples of the phased array components of the Lincoln program and the full radar system achievements of industry will be presented in rough time-order of achievement. A few remaining outstanding challenges will be discussed.
The Lincoln program began with an across-the-board attack on antennas, power amplifiers, receivers, beam-formers and control devices; the first goal was linear arrays which rapidly migrated to two dimensional arrays. It was clear that solid-state was the place to go but there were no high-frequency or high-power solid state devices to go to! In the mid 1960’s the nation undertook focused solid state device work at L-Band and that embryonic work carried us 40 years later to today’s fine X-band, all-solid-state radars .
The Laboratory program did make the industry and other laboratory connections and played a key role in getting things started. We thought it might take 10 to 15 years to “realize the vision”, but we were very optimistic , it took closer to 50 years but we are there today ( so there is hope for the Sox)!
Bill Delaney received his EE degree from Rensselear in 1957, joined Lincoln Laboratory and simultaneously entered the MIT Graduate School. He immediately became involved in phased-array radar with a thesis topic on: “Phase Stabilization of UHF Power Amplifiers” ( for phased arrays ). He rejoined the Special Radars Group in 1959 at the completion of his MSEE degree.
His 53 year association with Lincoln has led him in many directions: radar, phased array antennas, missile defense, air defense, wideband radar, air traffic control, tactical battlefield technology, GPS and participation in literally hundreds of special studies and task forces for the Department of Defense. He did a tour at the Kwajalein radar site and a tour in the Pentagon in DDR&E. He was appointed an Assistant Director of Lincoln in 1987 and since 1995 has been the Director’s Office Fellow at the Laboratory.
Bill is currently a Senior Fellow of the Defense Science Board and in 1995 he was elected a Fellow of the IEEE.
Meeting will be held at MIT Lincoln Laboratory A-Café, 244 Wood Street, Lexington, MA. For directions please see:http://www.ll.mit.edu/about/map.html
For more information, contact Antennas & Propagation chair, Gregory Charvat at Gregory.charvat@ll.mit.edu
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