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:
Aug. 09, 1983
Filed:
Sep. 01, 1981
Douglas A Spencer, Boulder, CO (US);
Bell Telephone Laboratories, Incorporated, Murray Hill, NJ (US);
Abstract
In a PAM bus switching bus which normally handles analog voice signals, the different DC offsets caused by the different buffing, summing and distribution amplifiers cause no ill effects because DC voltages are not passed by the remainder of the support elements. However, when it is attempted to switch logic level DC signals through such a PAM bus network, the DC offset which is an indeterminate function of the particular switching path established, makes it impossible to establish a uniform slicing level. In the illustrative embodiment a uniform slicing level is achieved by clamping the summing bus of the PAM system during a preamble of the time slot, measuring the offset on the distribution bus and then applying the measured offset to compensate the distribution bus during the remainder of the time slot when the actual data signal is allowed to be applied to the summing bus.