Jack C Walker

US Patent:

41919572, Mar 4, 1980

Filed:

Dec 12, 1975

Appl. No.:

5/640570

Inventors:

Jack L. Walker - Ann Arbor MI
Walter G. Carrara - Ann Arbor MI

Assignee:

Environmental Research Institute of Michigan - Ann Arbor MI

International Classification:

G01S 902

US Classification:

343 5PC

Abstract:

A method for range-Doppler imaging of rotating objects or of stationary scenes being tracked by a sensor carried by a moving vehicle includes the transmission and reception of sequential modulated signals, coherent demodulation of the received signals, recording of the demodulated signals, and a two-dimensional processing of the recorded signals to obtain a spatial image of the scene. In the disclosed inventive concept, the demodulated signals are recorded in a two-dimensional polar format wherein the angular coordinate of the signal on the recording medium is proportional to the relative angular position of the object or scene being imaged and the radial coordinate of the signal on the recording medium is proportional to the transmitted signal frequency within each transmitted pulse.