Accession Number : ADD015891

Title :   High Resolution Radar Profiling Using Higher-Order Statistics.

Descriptive Note : Patent, Filed 26 Jun 92, patented 13 Jul 93,

Corporate Author : DEPARTMENT OF THE NAVY WASHINGTON DC

Personal Author(s) : Pierce, Robert D

Report Date : 13 Jul 1993

Pagination or Media Count : 14

Abstract : A coherent radar is used for achieving high resolution radar imaging of a moving object in sea clutter and noise. A stored replica of the transmitted waveform is combined with the returned signal in a synchronous detector to produce in-phase and quadrature (I and Q or complex) samples. High resolution is achieved by transmitting a series of pulses, each at a different frequency, and then processing these complex samples to produce a synthetic down-range profile. To enhance the radar target or object from system noise and sea clutter, the complex I and Q (in-phase and quadrature component) samples from the radar are coherently averaged in a special two-dimensional slice of the trispectrum (e.g. quadruple product or fourth-order moment). This formulation of the fourth moment retains all important target information and suppresses Gaussian noise. Once averaged, a new set of I and Q samples are reconstructed that produce the same trispectral slice as this average. These reconstructed samples are then transformed using conventional Fourier transform methods to produce the average, or enhanced, down-range profile.

Descriptors :   *COHERENT RADAR, *PATENTS, *RADAR IMAGES, *TARGET DISCRIMINATION, *FOURIER TRANSFORMATION, CLUTTER, DETECTORS, FREQUENCY, GAUSSIAN NOISE, HIGH RESOLUTION, MOMENTS, NOISE, OCEANS, PROFILES, PULSES, RADAR, RADAR TARGETS, REPLICAS, SEA CLUTTER, TRANSMITTING, TWO DIMENSIONAL, WAVEFORMS, MOVING TARGETS, RADAR SIGNALS, SIGNAL TO NOISE RATIO, SIGNAL PROCESSING

Subject Categories : Active & Passive Radar Detection & Equipment
      Numerical Mathematics

Distribution Statement : APPROVED FOR PUBLIC RELEASE