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Air and spaceborne radar systems an introduction 2001
[...]... technicians, student engineers, and engineers working in radar research and development The many users of radar, as well as systems engineers and designers, should also find it of interest Airborne and spaceborne radar systems, themselves highly complex systems, are fitted to mobile and often rapidly changing platforms that contain many other items of equipment Radar can therefore not be considered... how the design of the radar is adapted to each The final chapters are devoted to a view of future technological developments and the ways that airborne and spaceborne radars may be expected to develop in response to new types of targets and missions The French radar industry has played a significant role in the development of many of the innovations in airborne and spaceborne radar The authors of this... are acknowledged as experts in the field and they provide a uniquely European perspective on the subject For all of these reasons, this book will be of value to a wide audience, both as a reference to radar engineers and those responsible for the specification and procurement of airborne and spaceborne radar systems, and as a textbook in graduate-level courses on radar Hugh Griffiths Professor, University... transmitter sending a continuous sinusoidal wave to a transmitting antenna and, for reception, an antenna plus a high-gain receiver and a detector whose output signal is displayed using a radar display such as a CRT The role of the transmitting antenna is to concentrate the energy transmitted in a chosen direction in space (beam center) The transmitting antenna gain, Gt , is maximum along the axis and. .. (tanks and trucks) and helicopters and on Synthetic Aperture Radar (SAR) imaging radars— which give a high-resolution picture of fixed echoes (steady vehicles, buildings, bridges, airfields, etc.) These ground surveillance missions are performed • • • by satellite SARs, which give very large accessibility and a very low update rate (hours to days) or by airborne standoff systems from large jet aircrafts,... fifty years, radar operational capability and performance have continued to improve, and one can safely assume that this will hold true for the coming decades This book, devoted to airborne and spaceborne radar, avoids a purely theoretical approach and is certainly not intended for an “elite” group of specialists Rather, it is a practical tool that we hope will be of major help to technicians, student... (late ‘60s) digital radars (‘70s) medium PRF radar (late ‘70s, early ‘80s) multimode programmable radar (mid-‘80s) airborne electronically scanned antenna radar (‘90s) The first radar images of the Earth were obtained in 1978 using Synthetic Aperture Radar (SAR), operating in the L-band (λ ≈ 30 cm) and mounted on the American satellite Seasat Resolution of the images obtained, both day and night, was close... reception frequency c TR/2= range domain without range ambiguity For example, TR = 100 µs, ∆f = 0.2 fm , and R = 3 km 1.2.1.2 The Invention of Monostatic Radar By pulsing the radar on and off, it is possible to use the same antenna for both transmission and reception During transmission, the highly sensitive input to the reception channel must be protected from the powerful transmission level This avoids... available volume and technology, etc As will be shown in a later section, the wavelength used for most airborne radars is situated in X-band, that is, in the 8-12.5 GHz frequency band (λ: 2.4-3.75 cm) /DFRPPH5DGDUERRN 3DJH 0RQGD\ )HEUXDU\ 30 2 Initial Statements of Operational Requirements 2.1 Introduction Nowadays airborne and space-based radars have some civilian applications,... oriented Airborne civilian applications concern mainly weather radars of liners and Exclusive Economic Zone surveillance (EEZ) Space-based civilian radars are used for global earth resource management In this section we focus on defense missions and military radar systems that gather the main technical issues 2.2 Missions We can divide operational missions into four main missions: • • • • surveillance . alt="" Air and Spaceborne Radar Systems: An Introduction Philippe Lacomme Jean-Philippe Hardange Jean-Claude Marchais Eric Normant Translated from the French by Marie-Louise Freysz and Rodger. specification and procurement of airborne and spaceborne radar systems, and as a textbook in graduate-level courses on radar. Hugh Griffiths Professor, University College London IEE PGEl5 Committee, IEEE Radar. development. The many users of radar, as well as systems engineers and designers, should also find it of interest. Airborne and spaceborne radar systems, themselves highly complex systems, are fitted