| 摘要 |
1,167,272. Random number generators. THOMSON-CSF. 19 Sept., 1967 [26 Sept., 1966], No. 42709/67. Heading G4D. A circuit for producing a second quasirandom number by operating on a first quasirandom number comprises an arrangement 1 of counters fed by a clock pulse source 2, the arrangement 1 providing N outputs to a circuit 3 which provides the first quasi-random number on n outputs 7. Each of the n outputs feeds a respective modulo-2 feedback shift register 4, the resulting n outputs 5 giving the second quasi-random number, which is used in a ciphering apparatus. Each register 4 comprises a modulo-2 adder fed by the output 7 and generating the output 5 which also passes to the first bi-stable stage of the register. The second input of the adder is derived from logical operations on the outputs of various stages in the register. Each register may have a different feed-back function. |
