Monitoring system for optical transmission line repeaters

• US 4,278,850 A
• Filed: 04/09/1979
• Issued: 07/14/1981
• Est. Priority Date: 04/11/1978
• Status: Expired due to Term

• Current Assignee: Kokusai Denshi Denwa Company Limited (KDDI Corporation)
• Original Assignee: Kokusai Denshi Denwa Company Limited (KDDI Corporation)
• Inventors: Sato, Masanori, Wakabayashi, Hiroharu, Niiro, Yasuhiko
• Primary Examiner(s): Malzahn, David H.
• Application Number:
  US06/028,312
• Time in Patent Office: 827 Days
• Field of Search: 179/175.31 R, 340/146.1 E, 340/146.1 C, 371/22
• US Class Current: 398/37
• CPC Class Codes: H04B 10/0777 Monitoring line amplifier or line repeater equipment
• CPC Class Codes: H04B 10/29 Repeaters
• CPC Class Codes: H04B 2210/072 using an overhead signal

Abstract

The error rate and the operation of repeaters inserted in an optical transmission line are monitored at the terminal station on land by transmitting the test signal and monitoring the response signal of repeaters through the optical data transmission line without utilizing interstitial copper pair. Each repeater has the particular identification code, and the transmission terminal transmits the test code having the repeater identification code and an acknowledgement block with an empty bit position on the time divisional basis with the data to be transmitted. The repeater which finds his identification code in the test code, inserts the response in the acknowledgement block, and repeats the signal including both said test code and the data to be transmitted. The reception terminal analyzes the response signal of each repeater to determine the error rate of each repeaters.

Claims

1. In an optical digital transmission system including a transmitting station coupled by way of a transmission line to a receiving station and at least one intermediate repeater station, the combination therewith of:

(a) optical pulse generating means at said transmitting station for establishing a test signal on a time divisional basis with the data to be transmitted, said test signal comprising an indentification code for identifying a particular repeater station and an acknowledgement block having an empty bit position,

(b) decoding means at said repeater station for decoding said identification code, said decoding means outputting an acknowledgement signal upon recognition of said identification code,

(c) delaying means at said repeater station coupled to the output of said decoding means for delaying said acknowledgement signal to achieve time coincidence with said empty bit position in said acknowledgement block, and

(d) gating means at said repeater station coupled to the outputs of said delaying means and the transmission line for combining said test and data signals with said acknowledgement signal on a time divisional basis for transmission to said receiving station.

2. The combination of claim 1 wherein said repeater station includes photoelectric conversion means coupled to said transmission line for converting between optical signals in said transmission line and electrical signals for use by said repeater station.

3. The combination of claim 1 wherein said repeater station includes regenerative recognition means coupled between said transmission line and said gating means for regenerating said test and data signals.

5. The combination of claims 1 or 4 wherein said acknowledgement signal is inserted in the transmission line.

6. The combination of claims 1 or 4 wherein said identification code comprises a plurality of sub-identification codes separated by alternating single bits of "1" and "0", said sub-identification codes having identical contents with respect to each other.

7. The combination of claims 1 or 4 wherein said transmission line includes an upward and downward direction, each direction having at least one repeater station, wherein said test signal flows in one of said directions and said acknowledgement signal is inserted in the other direction.

4. In an optical digital transmission system including a transmitting station coupled by way of a transmission line to a receiving station, and at least one intermediate repeater station, the combination therewith of:

(a) optical pulse generating means of said transmitting station for establishing a test signal on a time divisional basis with the data to be transmitted, said test signal comprising an identification code for identifying a particular repeater station and an acknowledgement block having an empty bit position,

(b) photoelectric conversion means at said repeater station for converting said optical signals in the transmission line into electrical signals,

(c) regenerative recognition means at said repeater station coupled to the output of said photoelectric conversion means for regenerating said test and data signals,

(d) decoding means at said repeater station coupled to the output of said photoelectric conversion means for decoding said identification code, said decoding means outputting an acknowledgement signal upon recognition of said identification code,

(e) delaying means at said repeater station coupled to the output of said decoding means for delaying said acknowledgement signal to achieve time coincidence with said empty bit position in said acknowledgement block,

(f) gating means at said repeater station coupled to the outputs of said delaying means and said regenerative recognition means for combining said test and data signals with said acknowledgement signal on a time divisional basis, and

(g) electric to photo conversion means at said repeater station coupled between the output of said gating means and the transmission line for converting electrical signals into optical signals for transmission to said receiving station.

8. A repeater for an optical transmission system comprising:

(a) photoelectric conversion means coupled to said optical transmission system for converting optical signals into electrical signals,

(b) equalization amplifier means coupled to the output of said photoelectric conversion means for equalizing and amplifying said signals,

(c) regenerative recognition means coupled to the output of said equalization amplifier for regenerating said signals,

(d) decoding means coupled to the output of said equalization amplifier means for decoding said signals, said decoding means outputting an acknowledgement signal upon recognition of the identification code of said repeater,

(e) delaying means coupled to the output of said decoding means for delaying said acknowledgement signal,

(f) gating means coupled to the outputs of said delaying means and said regenerative recognition means for combining said signals with said acknowledgement signal on a time divisional basis, and

(g) electric to photo conversion means coupled between the output of said gating means and the transmission system for converting said combined signals into optical signals.