Browse Prior Art Database

Backdoor Window Generator

IP.com Disclosure Number: IPCOM000046878D
Original Publication Date: 1983-Aug-01
Included in the Prior Art Database: 2005-Feb-07

Publishing Venue

IBM

Related People

Authors:
Bardell, PH McAnney, WH [+details]

Abstract

When a shift register latch (SRL) array of M shift register strings arranged in N rows is repetitively loaded with pseudo-random binary numbers from this linear feedback shift register (LFSR), the array has the property that each of 2mnl possible non-zero binary patterns is seen through a non-movable (m x n) window in 2mnl sequential reloadings of the array by the LFSR. The backdoor window generator will be a maximal-length linear-feedback shift register of m x n stages. A window of size m x n will require 2mnl unique reloadings of the array before all possible non-zero patterns cycle under the fixed window. Assume that 2mnl >> N and that N is relatively prime to 2mnl.