The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 02, 1980
Filed:
Feb. 15, 1979
Ben H Cantrell, Springfield, VA (US);
Bernard L Lewis, Oxon Hill, MD (US);
The United States of America as represented by the Secretary of the Navy, Washington, DC (US);
Abstract
A pulse expansion and compression system, especially useful for radar ranging, comprising a pulse coder for expanding an input pulse and a pulse compressor of the matched-filter type. The coder consists of a plurality of delay stages into which the input pulse is fed, a discrete Fourier transform (DFT) circuit to which the output signals of the delay stages are fed, a time-dispersionmeans (TDM) comprising an arrangement of delay stages for differently delaying the output signals from the DFT, and a coherent summer for adding the real and imaginary parts of the signals from the TDM. The summer output is fed to a phase modulator and then to the transmitter. The echo signals are conjugated, time-inverted, and passed through the same DFT as the input pulse signal. The outputs of the DFT are then passed through a TDM of the same type as the first TDM, but this time in time-inverted order. The outputs of the second TDM are fed through a coherent summer and an envelope detector to provide a cross-correlated facsimile of the original input pulse.