JP2005303412A - Alarm transmission system and alarm transmission method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an alarm transmission system and an alarm transmission method by decreasing the number of wires interconnecting an intra-office interface section and an inter-radio interface section so as to downsize a connector of a connection section resulting in downsizing an apparatus. <P>SOLUTION: The alarm transmission system or the like includes: an interface section 2 having an interface circuit 12 located at a receiver side of a transmission line for detecting a fault wherein a transmission signal 108 cannot be recovered and providing an output of a result of the detection as an alarm signal, and a pattern insertion circuit 13 for inserting a prescribed fixed pattern to the transmission signal by using the alarm signal; and an intra-office interface section 1 having a pattern detection circuit 14 for detecting a pattern of an in-apparatus transmission signal outputted from the interface section 2 and an interface signal switching circuit 42 for receiving a control signal from the pattern detection circuit and transmitting a prescribed pattern in place of the transmission signal on the occurrence of the fault wherein the transmission signal cannot be recovered. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an alarm transmission system and an alarm transmission method, and more particularly to a system and method for transmitting an alarm related to radio failure information on the receiving side of an inter-radio transmission path.

  Conventionally, when transmitting an alarm to an inter-radio transmission line, a dedicated channel for transferring maintenance information such as alarm information is provided in advance in the transmission signal, or if it is in the same device, the alarm information is separated from the transmission signal path. A dedicated transmission path was provided to transmit alarm signals.

  For example, in the wireless point-to-point system described in Patent Document 1, an intra-station interface unit 1 and an inter-wireless interface unit 2 are provided in each of the A and B stations, which are each terminal station, as shown in FIG. Prepare. The in-station interface unit 1 transmits / receives and processes transmission signals in accordance with ITU-T recommendations, such as SDH (Synchronous Digital Hierarchy) signals. The inter-wireless interface unit 2 converts / inverts a transmission signal into a radio-specific frame signal, and transmits / receives a modulation / demodulation signal. Here, in order to transmit maintenance information, this system was provided with three dedicated channels.

  On the other hand, in the conventional circuit shown in FIG. 10, failure information generated between radios, such as a level alarm of a modulation / demodulation signal generated in the modulation / demodulation part and a synchronization alarm of a radio frame signal, here, alarm signal A (106), alarm signal After B (107) was detected by the inter-wireless interface unit 62, it was separately transmitted to the intra-station interface unit 61 via a wiring different from the transmission signal.

  The intra-office interface unit 61 avoids transmission errors due to noise generated on the wiring from the inter-radio interface unit 62 to the intra-office interface unit 61 in the radio alarm signal A (106) and the alarm signal B (107). Therefore, the protection circuit 63 is provided so that the control signals A (109) and B (110) for processing the transmission signal are not erroneously output.

  As shown in FIG. 11, the protection circuit 63 includes an N-time continuous alarm state detection circuit 81, an M-time continuous normal state detection circuit 82, and a holding circuit 83 on the alarm signal A (106) side. The signal B (107) side also includes a circuit similar to the above. In the following description of the operation of the protection circuit 63, only the alarm signal A (106) is shown, and the description of the alarm signal B (107) is omitted.

  As shown in FIG. 12, in the protection circuit 63, the state of the alarm signal is counted by the timing signal 113 having an arbitrary period, and when the normal state is counted M (M ≧ 1: integer) times or more, the normal state is M times. If the detection circuit 82 sets the control signal to the normal state (FIG. 12: (3)) and the alarm state is N (N ≧ 1: integer) times or more, the N-th continuous alarm state detection circuit 81 sets the control signal to the alarm state. (FIG. 12: (1)).

  Here, as indicated by (2) in FIG. 12, even if the alarm signal instantaneously enters the alarm state due to the influence of transmission noise between the wirings, as long as the condition of the protection circuit 63 is not satisfied, Since the holding circuit 83 holds the result, the state due to noise is ignored, and a stable control signal is output. Thereafter, according to the A control signal 109 and the B control signal 110, the transmission signal is processed by forcibly inserting an AIS (Alarm Indicate Signal) into the transmission signal.

  On the other hand, in the alarm transfer circuit described in Patent Document 2, when there is no input signal of the transmission signal 102 on the transmission side sent from the in-station interface unit 61 to the wireless interface unit 62 shown in FIG. The wireless transmission signal 103 on the wireless transmission side is transmitted in a fixed pattern, and the information is transferred to the opposite station.

JP 63-104561 A JP-A-11-127221

  However, in the above-described conventional technique, first, in the maintenance information transfer system described in Patent Document 1, since alarm information is multiplexed in addition to the signal to be originally transmitted, the transmission speed is increased more than originally and the effective use of the frequency is called. There was a problem in terms.

  When transmitting signals between radios, in addition to transmission signals (signals in existing formats such as SDH), local station alarm information, station information, auxiliary transmission signals, etc. that must be transmitted to the opposite station are multiplexed. The Assuming that the transmission rate of the transmission signal is Fbps, additional information fbps is added to Fbps in order to send inter-radio information, and the inter-radio transmission rate is (F + f) bps. Therefore, if the amount of inter-radio information to be transmitted in addition to the transmission signal increases, the amount of additional information increases and the radio frequency also increases.

  However, the frequency band that can be used wirelessly is regulated, and there is an upper limit for the wireless frequency, so the amount of information that can be added is also limited. Further, if the frequency is increased, transmission by a technique such as a multi-level modulation method is required. However, the multi-level modulation method is weak against errors between radio waves, and the transmission path length is limited.

  As described above, since the disadvantage of increasing the radio frequency is large, it is desirable to reduce the additional information between radios as much as possible. However, in the system described in Patent Document 1, the problem is that the additional information between radios tends to increase. was there.

  Next, as a second problem, when alarm information is transmitted from the alarm detection unit to another unit in the same device as in the system described in Patent Document 1, a separate transmission path is secured for each alarm. As necessary, the wiring in the device increases by the number of alarms. This makes it difficult to reduce the size of the motherboard of the apparatus, and the wiring interval is not sufficient, so that transmission noise between the wirings easily occurs. However, noise cannot always be quantified, and there has been a problem that it becomes complicated to examine a protection circuit for removing the influence of noise.

  Thirdly, as in the alarm transfer circuit described in Patent Document 2, when transmitting and receiving a unique pattern in the transmission unit between radios, if the unique pattern is transmitted as a wireless transmission signal, the transmission power density is biased. Occurs. However, wireless transmission is a problem because it assumes that the transmission power density is flat.

  Therefore, the present invention has been made in view of the problems in the above-described conventional technology, and reduces the number of wires connecting the intra-station interface unit and the inter-wireless interface unit, thereby reducing the size of the connector of the connection unit. An object of the present invention is to provide an alarm transmission system and an alarm transmission method capable of reducing the size of the apparatus.

  In order to achieve the above object, the present invention provides an alarm transmission system, a failure detection circuit for detecting a failure state of a received transmission line, a failure state detected by the failure detection circuit, and a circuit in the next stage And a switching circuit that performs switching control to another signal instead of the transmission signal originally transmitted.

  And according to the present invention, when the failure detection circuit detects the failure state of the transmission path, the switching circuit transmits the signal transmitted to the next-stage circuit in place of the transmission signal originally transmitted. The number of wires for transmitting the alarm can be reduced, and the apparatus can be miniaturized.

  In the alarm transmission system, when a failure state is detected by the failure detection circuit, a pattern insertion circuit for fixing the transmission signal itself to a unique pattern, and a detection circuit for detecting a unique pattern fixed by the pattern insertion circuit In addition, when the detection circuit detects the fixed pattern, the transmission signal originally transmitted by the switching circuit can be switched to another signal.

  Further, the present invention is an alarm transmission system, on the reception side of the transmission path, detecting a failure in which the transmission signal cannot be restored, using an interface circuit that outputs a detection result as an alarm signal, and the alarm signal, An interface unit having a pattern insertion circuit for inserting a predetermined fixed pattern into a transmission signal, a pattern detection circuit for detecting a pattern of an in-device transmission signal output from the interface unit, and a control signal from the pattern detection circuit An in-station interface unit having an interface signal switching circuit for sending a predetermined pattern in place of the transmission signal when a failure occurs when the transmission signal cannot be restored.

  According to the present invention, the interface circuit uses an alarm signal output by detecting an unrecoverable failure of the transmission signal on the receiving side of the transmission line, the pattern insertion circuit inserts a predetermined fixed pattern into the transmission signal, The detection circuit detects the pattern of the in-device transmission signal output from the interface unit, and the interface signal switching circuit sends out a predetermined pattern instead of the transmission signal, so the in-station interface unit and the inter-wireless interface unit are connected. The number of wiring to be reduced can be reduced. As a result, it is possible to reduce the size of the connectors at the connecting portions of both parts, and consequently, it is possible to reduce the size of the entire apparatus.

  In the alarm transmission system, the pattern detection circuit of the intra-office interface unit has a protection circuit that protects the pattern match or mismatch information when detecting the pattern of the in-device transmission signal output from the interface unit. Can be configured. As a result, even if an error due to a radio transmission path error or the like occurs in the transmission signal or an error due to interference between patterns or the like, it is possible to prevent the transmission signal from being switched immediately.

  Further, the present invention is an alarm transmission method, which detects a failure state of a received transmission path, inputs a signal of the detected failure state, and transmits a signal to be transmitted to a next stage circuit. It is characterized by switching to another signal. As a result, as described above, the number of wires for transmitting an alarm can be reduced, and the apparatus can be miniaturized.

  In the alarm transmission method, when the failure state is detected, the transmission signal itself is fixed to a unique pattern, and the signal transmitted to the next stage circuit is originally transmitted by detecting the fixed unique pattern. It is possible to switch to a signal different from the transmission signal.

  According to the alarm transmission system and the alarm transmission method according to the present invention, it is possible to reduce the number of wirings connecting the intra-station interface unit and the inter-wireless interface unit, and downsize the connectors and the like of the connection units of both units. Therefore, it is possible to reduce the size of the entire apparatus.

  FIG. 1 is a block diagram of a terminal station to which an alarm transmission system and an alarm transmission method according to the present invention are applied. An intra-office interface unit 1 includes an intra-office interface circuit 11 and a pattern detection circuit 14, and an inter-radio interface unit 2 Includes a wireless interface circuit 12 and a pattern insertion circuit 13.

  As shown in FIG. 2, the pattern insertion circuit 13 of the inter-wireless interface unit 2 includes a pattern generation circuit 32 that outputs a pattern A (301) and a pattern B (302) corresponding to the failure that has occurred, a signal switching circuit 31, Is provided.

  As shown in FIG. 3, the pattern detection circuit 14 of the in-station interface unit 1 determines whether the in-device transmission signal 108 output from the inter-wireless interface unit 2 is the pattern A (301) or the pattern B (302). Therefore, an A pattern comparison circuit 21 and a B pattern comparison circuit 22 are provided. The A pattern comparison circuit 21 and the B pattern comparison circuit 22 respectively compare the patterns, and output the match information 201 and 203 when the comparison results match, and the mismatch information 202 and 204 when they do not match. Then, the A control signal (109) and the B control signal (110) determined by the protection circuit 23 are output.

  As shown in FIG. 4, the intra-office interface circuit 11 includes an AIS generation circuit 41 and an interface signal switching circuit 42. Here, a circuit that performs signal processing in accordance with the ITU-T recommendation, such as processing of an SDH signal, is not directly related to the present invention, and thus illustration and description thereof are omitted.

  As shown in FIG. 7, the protection circuit 23 of the pattern detection circuit 14 shown in FIG. 3 includes an M-time continuous match detection circuit 231 and an N-time continuous mismatch detection circuit on the A pattern comparison circuit 21 (see FIG. 3) side. 232, and the B pattern comparison circuit 22 (see FIG. 3) side also includes a similar circuit.

  Next, the operation of the alarm transmission method having the above configuration will be described.

  As shown in FIG. 1, on the receiving side of the inter-wireless interface circuit 12, when a fatal failure such as reception signal disconnection or wireless frame signal asynchronous occurs, transmission is performed by the pattern insertion circuit 13 according to the type of failure. Insert a unique pattern into the signal and send it out. Here, the fatal failure means a failure that prevents the transmission signal from being reproduced.

  As shown in FIG. 5, the pattern generation circuit 32 of the pattern insertion circuit 13 shown in FIG. 2 has a pattern A (301: repeated pattern of “001”) and a pattern B (302: “101”) corresponding to the alarm. "Repetition pattern" is always output. The bit rate of the pattern is the same as the transmission rate of the regular transmission signal.

  When the alarm signal A (106) or the alarm signal B (107) which is fatal alarm information is generated in the wireless interface circuit 12 of FIG. 1, the signal switching circuit 31 (see FIG. 2), according to each alarm, pattern A (301) in the case of alarm signal A (106), pattern B (302) in the case of alarm signal B (107), no alarm is generated If so, the demodulated transmission signal 105 is selected and output to the intra-station interface unit 1 as an inter-device transmission signal 108.

  Here, when the alarm signal A (106) or the alarm signal B (107) is generated, the received transmission signal 105 is completely repainted with a unique pattern, but the alarm signal A (106) or the alarm signal B ( 107) indicates a fatal failure between radios, and thus the received transmission signal 105 cannot be reproduced, and there is no effect even if a new pattern is inserted.

  In the intra-station interface unit 1 shown in FIG. 1, the in-device transmission signal 108 output from the inter-wireless interface unit 2 is transmitted to the pattern detection circuit 14 of the pattern detection circuit 14 of FIG. Comparison is performed, and if the comparison results match, match information 201 and 203 are output, and if they do not match, match information 202 and 204 are output.

  Next, the operation of the comparison circuits 21 and 22 will be described with reference to FIG. In the figure, the operation when the in-device transmission signal 108 matches the pattern A301 is shown.

  The intra-device transmission signal 108 that arrives between times t1, t2, and t3 is compared with pattern A301 or pattern B302, and coincidence information 201 and 203 or mismatch information 202 and 204, which are comparison results, are output at time t4. As shown in the figure, if the pattern A 301 (repetitive pattern of “001”) matches, the pattern A match information 201 enters a match detection state at time t 4, and the pattern A mismatch information 202 includes a mismatch non-detection state, a pattern The B match information 203 is in a non-match detected state, and the pattern B mismatch information 204 is in a mismatch detected state at time t4.

  In order to prevent the transmission signal 111 (see FIG. 1) from being switched immediately even if an error due to a radio transmission path error or the like occurs in the in-device transmission signal 108 or an error due to interference between patterns or the like, The detection circuit 14 is provided with a protection circuit 23 for matching / mismatching information (see FIG. 7).

  In FIG. 7, if the coincidence information 201 of the pattern A coincides with any M consecutive times, as shown in (1) of FIG. 8, the M successive coincidence detection circuit 231 controls the holding circuit 233 to control the A control signal. 109 is set to a normal state. If the mismatch information 202 is in the mismatch state N times or more, the N-time consecutive mismatch detection circuit 232 controls the holding circuit 233 to place the A control signal 109 in the alarm state as shown in (3) of FIG. Further, as shown in FIG. 8 (2), even if noise or the like is generated in the in-device transmission signal 108 and it is determined that there is no coincidence for the time, the A control signal is Hold previous judgment results.

  When the A pattern comparison circuit 21 in FIG. 3 sends the coincidence information 201, the in-device transmission signal cannot send the coincidence information 203 by the B pattern comparison circuit 22, and conversely, the B pattern comparison circuit 22 transmits the coincidence information 203, the in-device transmission signal 108 cannot send the coincidence information 201 by the A pattern comparison circuit 21, so that the A control signal 109 and the B control signal 110 are simultaneously controlled. The control by the interface signal switching circuit 42 in FIG. 4 is stable.

  As described above, the output of the protection circuit 23 is output to the in-station interface circuit 11 as the A control signal 109 or the B control signal 110 which is a determined control signal.

  As shown in FIG. 1, the A control signal 109 or the B control signal 110 from the pattern detection circuit 14 is input to the in-station interface circuit 11, and when each control signal is in an alarm state, the interface signal switching circuit of FIG. At 42, the AIS signal 401 is selected as the transmission signal 111, and if it is normal, the in-device transmission signal 108 is selected and output.

  As described above, in the present invention, pattern detection is performed to detect and distinguish between alarms between radios, and in-device transmission signals that are exchanged between the intra-station interface unit 1 and the inter-radio interface unit 2 are as follows: By changing according to the failure status between radios, wiring of a plurality of alarm signals can be avoided.

  In the above embodiment, the case of a wireless point-to-point system, which is a form of an inter-wireless transmission apparatus, has been described as an example. Similarly, in a wired transmission path, a failure detection unit and transmission signal processing It is obvious that the same effect can be obtained if the system transmits / receives alarm information to / from the unit and performs some processing on the transmission signal according to the alarm information.

  In the above embodiment, two types of alarm signals are described. However, the types of alarms to be transferred can be increased by increasing the repetition pattern length.

1 is a terminal block diagram in a wireless point-to-point system to which an alarm transmission system and an alarm transmission method according to the present invention are applied. FIG. It is a block diagram which shows the pattern insertion circuit of the interface part between radio | wirelesses of the system of FIG. FIG. 2 is a block diagram showing a pattern detection circuit of an intra-office interface unit of the system of FIG. 1. It is a block diagram which shows the transmission side of the in-station interface circuit of the in-station interface part of the system of FIG. It is a figure which shows each signal of the pattern insertion circuit of FIG. It is a figure which shows the operation example of the pattern comparison circuit of the pattern detection circuit of FIG. FIG. 4 is a block diagram illustrating an example of a protection circuit of the pattern detection circuit of FIG. 3. It is a figure which shows the operation example of the protection circuit of FIG. It is a block diagram which shows the conventional wireless point-to-point system. It is a terminal block diagram in a wireless point-to-point system using a conventional alarm transmission method. It is a block diagram which shows an example of the conventional protection circuit. It is a figure which shows the operation example of the conventional protection circuit.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Intra-station interface part 2 Inter-wireless interface part 11 In-office interface circuit 12 Inter-wireless interface circuit 13 Pattern insertion circuit 14 Pattern detection circuit 101 Inter-station interface part received signal 102 Transmission signal (radio transmission side)
103 Wireless transmission signal (wireless transmission side)
104 Wireless transmission signal (wireless reception side)
105 Transmission signal (wireless reception side)
106 Alarm signal A
107 Alarm signal B
108 In-device transmission signal 109 A control signal 110 B control signal 111 Inter-station interface section transmission signal 21 A pattern comparison circuit 22 B pattern comparison circuit 23 Protection circuit 201 A pattern match information 202 A pattern mismatch information 203 B pattern match information 204 B Pattern mismatch information 31 Signal switching circuit 32 Pattern generation circuit 301 Pattern A generated by the pattern generation circuit
302 Pattern B generated by the pattern generation circuit
41 AIS generation circuit 42 Interface signal switching circuit 401 AIS signal 61 (Conventional) Inter-station interface circuit 62 (Conventional) Inter-radio interface circuit 63 (Conventional) protection circuit 113 Arbitrary timing used for (Conventional) protection circuit Signal 81 (Conventional) Protection circuit N times continuous alarm state detection circuit 82 (Conventional) Protection circuit M times continuous normal state detection circuit 83 (Conventional) Holding circuit 231 Protection circuit M times continuous coincidence detection circuit 232 Protection Circuit N-time continuous mismatch detection circuit 233 holding circuit

Claims (6)

A failure detection circuit for detecting a failure state of the received transmission path;
An alarm transmission comprising: a switching circuit that inputs a fault state detected by the fault detection circuit and controls a signal to be transmitted to the next stage circuit to be switched to another signal instead of a transmission signal to be originally transmitted system. When a failure state is detected by the failure detection circuit, a pattern insertion circuit that fixes the transmission signal itself to a unique pattern;
A detection circuit for detecting a unique pattern fixed by the pattern insertion circuit,
The alarm transmission system according to claim 1, wherein when the detection circuit detects the fixed pattern, the transmission signal originally transmitted by the switching circuit is switched to another signal. An interface circuit for detecting a failure in which the transmission signal cannot be restored on the receiving side of the transmission line and outputting the detection result as an alarm signal, and a pattern insertion circuit for inserting a predetermined fixed pattern into the transmission signal using the alarm signal An interface unit having
A pattern detection circuit for detecting the pattern of the in-device transmission signal output from the interface unit, and a control signal from the pattern detection circuit are input, and the transmission signal is replaced in the event of a failure in which the transmission signal cannot be recovered. And an in-station interface unit having an interface signal switching circuit for transmitting a predetermined pattern.   4. The pattern detection circuit of the in-station interface unit includes a protection circuit that protects pattern matching or mismatch information when detecting a pattern of an in-device transmission signal output from the interface unit. The alarm transmission system described in. Detects the fault condition of the received transmission path,
An alarm transmission method, wherein a signal transmitted to the next-stage circuit by inputting the detected fault state is switched to a signal different from a transmission signal originally transmitted. Upon detecting the fault condition, the transmission signal itself is fixed to a unique pattern,
6. The alarm transmission method according to claim 5, wherein a signal transmitted to the next stage circuit is switched to a signal different from a transmission signal originally transmitted by detecting the fixed unique pattern.

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