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2010 International Waveform Diversity and Design Conference, 2010
Modern military airborne radars are highly sophisticated, multi-mode systems which are required to detect difficult targets in all aspects and over a large range/velocity detection space. There are particular difficulties associated with the airborne case such as the limited antenna aperture, high platform velocity and severe clutter levels which ...
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Modern military airborne radars are highly sophisticated, multi-mode systems which are required to detect difficult targets in all aspects and over a large range/velocity detection space. There are particular difficulties associated with the airborne case such as the limited antenna aperture, high platform velocity and severe clutter levels which ...
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Pulsed Doppler radar detects weather hazards to aviation
19th Aerospace Sciences Meeting, 1981Over the last several years experiments were conducted with a pulsed Doppler radar that have significant consequences for hazard detection in the en route and terminal areas. Mesocyclones can be detected to over 250 km while tornadoes are seen to about 150 km.
D. S. Zrnic, J. T. Lee
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2004
A Doppler radar is defined by as 'a radar which uses the Doppler effect to determine the radial component of relative radar target velocity or to select targets having particular radial velocities.' A pulse-Doppler (or pulsed-Doppler) (PD) radar is defined as 'a Doppler radar that uses pulsed transmissions.' PD radar is used extensively for detecting ...
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A Doppler radar is defined by as 'a radar which uses the Doppler effect to determine the radial component of relative radar target velocity or to select targets having particular radial velocities.' A pulse-Doppler (or pulsed-Doppler) (PD) radar is defined as 'a Doppler radar that uses pulsed transmissions.' PD radar is used extensively for detecting ...
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Tornado Detection by Pulsed Doppler Radar
Monthly Weather Review, 1978Abstract Doppler radar measurements in the Union City, Okla., tornadic storm of 24 May 1973 led to discovery of a unique tornadic vortex signature (TVS) in the field of mean Doppler velocity data. The distinct character of this signature and its association with the tornado are verified using a model that simulates Doppler velocity measurements through
Rodger A. Brown +2 more
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Probing tornadoes with a pulse doppler radar
Quarterly Journal of the Royal Meteorological Society, 1977AbstractMaximum tornado wind speeds and their radii are deduced by least square fitting of the vortex model velocity spectra to those measured with a pulse Doppler radar. Spectra are analysed from the Stillwater, Oklahoma, 13 June 1975, tornado. Simulated spectra are fitted to those measured for pulse volume gates nearest the vortex, and thus a tornado'
D. S. Zrnic +3 more
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1993
This chapter deals with Doppler techniques and their different applications for surveillance radar, multifunction radar and synthetic aperture radar. The chapter presents: an analysis of a simple pulse Doppler radar [fixed station, low pulse repetition frequency (PRF), no range ambiguity] (radar characteristics, power and spectra of clutter and target,
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This chapter deals with Doppler techniques and their different applications for surveillance radar, multifunction radar and synthetic aperture radar. The chapter presents: an analysis of a simple pulse Doppler radar [fixed station, low pulse repetition frequency (PRF), no range ambiguity] (radar characteristics, power and spectra of clutter and target,
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2014
The main objective of this chapter is to describe how an airborne pulse-Doppler radar isolates targets of interest from clutter and measures target range and velocity. Related topics such as pulse compression, automatic detection, target tracking, and target and clutter statistics are described.
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The main objective of this chapter is to describe how an airborne pulse-Doppler radar isolates targets of interest from clutter and measures target range and velocity. Related topics such as pulse compression, automatic detection, target tracking, and target and clutter statistics are described.
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Radar pulse Doppler et filtrage adapté
Annales des Télécommunications, 1970La theorie du filtre adapte, en tant qu’optimalisation de rapport signal a bruit en sortie d’un recepteur radar, est desormais bien etablie et sert de reference dans tout calcul de portee. Les radars de type pulse Doppler, avec formation de voies distance, utilisent une technique du filtrage fondamentalement differente du filtre adapte.
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Non-uniform PRI pulse-Doppler radar
1993 (25th) Southeastern Symposium on System Theory, 2002Nonuniform pulse repetition interval (PRI) pulse-Doppler waveforms are processed by replacing the fast Fourier transform algorithm in standard pulse-Doppler processors with a more general discrete Fourier transform. Clutter rejection is a problem because the well-understood techniques of amplitude windowing are not available.
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1987
Relative motion between a signal source and a receiver creates a Doppler shift of the source frequency. Likewise, when a radar system illuminates a moving target that has a radial velocity component relative to the radar, the signal reflected from the target and received by the radar is also frequency shifted.
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Relative motion between a signal source and a receiver creates a Doppler shift of the source frequency. Likewise, when a radar system illuminates a moving target that has a radial velocity component relative to the radar, the signal reflected from the target and received by the radar is also frequency shifted.
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