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:
May. 15, 1979
Filed:
Feb. 17, 1978
Chung-Li Ren, Andover, MA (US);
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Abstract
A 90 degree phase stepper is described comprising a tandem array of three, 3 db hybrid couplers where the first and third couplers are of one variety (either 90 degree or 180 degree couplers) and the second is of the other variety. A pair of variable phase shifters are located in the two wavepaths connecting the first and second couplers, and a single variable phase shifter is included in one of the two wavepaths connecting the second and third couplers. Each phase shifter introduces either a zero or a 180 degree phase shift. By the appropriate selection of phase shifts, the phase of the output signal can be stepped in 90 degree increments. The stepper is designed for use in the signal combining circuit of a space diversity system. It is an advantage of the circuit that all of the received signal is preserved.