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:
Jun. 09, 1987
Filed:
May. 31, 1984
Kuo-Hsiung Yen, Manhattan Beach, CA (US);
Robert B Stokes, Torrance, CA (US);
Marshall Y Huang, Rancho Palos Verdes, CA (US);
TRW Inc., Redondo Beach, CA (US);
Abstract
A surface acoustic wave (SAW) device, and corresponding method, for expanding or contracting the time scale of an input signal that varies in time but is limited to a predetermined time interval. One embodiment of the invention achieves time expansion or compression by means of two Fourier transformations providing different chirp rates, and implemented in a form that includes only five SAW dispersive delay lines. In the illustrative version of this embodiment, three of the dispersive delay lines are used in conjunction with multipliers or mixers, and two are used as convolvers. Another embodiment of the invention uses only three SAW dispersive delay lines, two in conjunction with multipliers and one located between the multipliers to effect the desired time-scale change. A third embodiment of the invention employs a SAW tapped delay line and an associated set of gates to select successive data bit signals from successive output taps in the delay line. A SAW fill-in filter is used to fill in inter-bit gaps resulting from the use of the tapped delay line.