Ubiquitous radar: an implementation concept
James J. Alter - Naval Research Lab, Irwin D Olin - SFA, Inc., Clifford L. Temes - SFA, Inc., Frank F. Kretschmer - , Richard M. White - Naval Research Laboratory
Tue, 27 April 2004, 1:30 PM - 3:20 PM
Contemporary signal processing combined with phased array technology using digital beamforming enables development of an important new radar system class that provides continuous and uninterrupted multifunction capability within a coverage volume. The central idea of Ubiquitous Radar is to ?look everywhere all of the time.? The concept requires illuminating a wide coverage volume while continuously receiving signals from a ?pincushion? of narrow beams filling the volume. There are no gaps either in coverage space or in time, so that all targets can be detected at the earliest time and tracks initiated. Conceptually this technology can combine surveillance, tracking and weapon control. Continuous coverage from close-in ?pop-up? targets in clutter to long-range targets impacts selection of waveform parameters. The CPI (coherent processing interval) must be long enough to achieve a signal-to-noise ratio significantly above 0 dB in order to efficiently perform non-coherent integration. The approach, sometimes termed ?track-before-detect? then accounts for range-walk and Doppler-slide to achieve a specified detection probability. The current state-of-the-art in digital processing technology, particularly the use of field programmable gate arrays (FPGAs), makes the concept feasible.
The paper highlights the design of a surveillance and tracking system operating in L-band using a transmit array with 209 transmit elements each radiating 1 kW and a 1590 element receive array. The concept incorporates a digital receiver behind every element, a full digital beamformer producing 192 simultaneous receive beams and signal processing for every beam. Details concerning beamforming, waveform design, approaches to resolve range and Doppler ambiguities, effects of necessary long-time non-coherent integration, signal processing and false target rejection in the tracker are presented in detail.
Mr. James J. Alter - Naval Research Lab
James J. Alter received the B.S.E.E. and M.S.E.E. degrees from the University of Maryland in 1973 and 1981, respectively. He has worked in the Radar Division of the Naval Research Laboratory since 1973, where he is currently Head of the Advanced Radar Systems Branch. His main area of interest is in the development of real-time radar signal processors.
Mr. Irwin D Olin - SFA, Inc.
Irwin Olin received his BSEE from the Newark College of Engineering in 1949 and the MS in Engineering from Rutgers University in 1951. Since that time he has been primarily associated with the Radar Division at the Naval Research laboratory. Work has included microwave components, dynamic radar area measurements, radar sea clutter theory, ECCM and counter-ARM technology. He also served as an exchange scientist with the Royal Signals and Radar Establishment (UK) and during military service as a Technical Officer at the Aberdeen Proving Ground. He currently serves as a consultant to NRL's Radar Division, involved in aspects of the Navy's Advanced Multifunctional RF Concept (AMRFC). Mr Olin is a Life Fellow IEEE and a MSS Fellow.
Dr. Clifford L. Temes - SFA, Inc.
Dr. Temes has about 50 years of professional experience in electrical engineering, with approximately 45 years being in radar-related areas. For 17 years, he was Head of the Search Radar Branch, Radar Division, at the Naval Research Laboratory. He was also employed previously at SENTEL Corporation, MITRE Corporation, General Research Corporation, Federal Scientific Corporation, Columbia University Electronics Research Laboratory and National Advisory Committee for Aeronautics (now NASA).
Dr. Frank F. Kretschmer -
Frank F. Kretschmer received the BS,MS,and PH.D degrees in electral engineering from the Pennsylvania State University, Drexel Institute of Technology and the Johns Hopkins University respectively. He has been employed by the Burroughs Corp., Bendix Radio and Johns Hopkins University. From 1970 to 1990, he was with the Naval Research Laboratory, Washington,D.C. where he conducted research and published papers in the areas of adaptive processing, MTI, and pulse compression waveform design. Since 1990 he has been a consultant. Dr. Kretschmer is a Fellow of IEEE and co-author of the book Aspects of Radar Signal Processing.
Mr. Richard M. White - Naval Research Laboratory
Richard White received his BSEE degree from the University of Maryland in 2001. He has since worked in the Radar Division of the Naval Research Laboratory in Washington, DC. His main area of focus is in analog and digital design.