Title:
PCM CHUKEISHOGAITANSAKUHOSHIKI OYOBI FUGOHATSUSEISOCHI
Document Type and Number:
Japanese Patent JPS51107707
Kind Code:
A
Abstract:
A PCM fault location system for repeaters and a code generator used therefor employ fault location codes generated on the basis of pseudo-random codes. The PCM fault location system transmits the codes through a repeatered transmission line, and the fault location codes including repeater transmission errors are received by the repeaters. A component of the repeater-designation frequency signal is extracted from the received fault location codes by means of a particular repeater-built-in fault locating circuit, and the thus extracted repeater-designation frequency component is received at a transmitting point of the fault location codes. The code generator employed at the transmitting point includes first means for obtaining codes which have an appropriate and sufficient difference in an average number of occurrences of digits "1" and "0" and are constructed using at least one series of pseudo-random codes, second means for controlling the state of the codes obtained by the first means in accordance with a repeater-designation frequency signal, and third means for performing differential code-conversion of the codes obtained by the second means.
Inventors:
HIGO KEIKI
Application Number:
JP3275675A
Publication Date:
September 24, 1976
Filing Date:
March 18, 1975
Export Citation:
Assignee:
NIPPON ELECTRIC CO
International Classes:
H04B17/00; H04B17/17; H04L25/02; H04B17/29; H04B17/40; H04J3/14; (IPC1-7): H04B3/46; H04J3/14