CN101404542B

CN101404542B - Method for eliminating random PPI-AIS alarm at circuit self-loop of 2M interface in SDH equipment

Info

Publication number: CN101404542B
Application number: CN2008102244058A
Authority: CN
Inventors: 刘爱军; 陈思思
Original assignee: Fiberhome Telecommunication Technologies Co Ltd
Current assignee: Fiberhome Telecommunication Technologies Co Ltd
Priority date: 2008-10-14
Filing date: 2008-10-14
Publication date: 2011-05-04
Anticipated expiration: 2028-10-14
Also published as: CN101404542A

Abstract

The invention discloses a method for eliminating random occurrence of PPI-AIS alarms during circuit self-loop of a 2M interface in an SDH device. The method is characterized in that when a PPI-LOS alarm appears or disappears, a segment of pseudo-random codes is forcibly inserted into an up-channel or a down-channel direction of a 2M branch circuit to eliminate the delivery of all '1' code streams, and to further eliminate the unnecessary PPI-AIS alarm caused by the circuit self-loop, wherein, the pseudo-random codes can not only be inserted in a software manner, but also be inserted by introducing a programmable logic unit behind the 2M interface chip in a hardware manner.

Description

The 2M interface method that PPI-AIS alarms occurs at random at circuit in the elimination SDH equipment when encircling

Technical field

The present invention relates to optical communication field, the 2M interface that is specifically related to a kind of light synchronizing digital transmission equipment is eliminated the method that the PPI-AIS alarm appears in physics mouth at random at the transmitting-receiving circuit when encircling.

Background technology

The Optical synchronization digital transmission network is made up of some synchronous digital transmission (SDH) network elements, carries out synchronizing information transmission, multiplexing and cross-coupled network on optical fiber.It has the unified Network-Node Interface in the whole world (NNI), thereby has simplified the transmission of the intercommunication of signal and signal, multiplexing, interconnection and exchange process.The network of setting up by the synchronous digital transmission is a high unity, standard, intelligentized network, and has realized the transverse compatibility of equipment, and each user of the whole world can be communicated by letter whenever and wherever possible easily.The synchronous digital transmission technology has become the one preferred technique of each telecom operators' networking of the world today.

Light synchronizing digital transmission equipment generally uses the same switch of 2M interface, the base station, and equipment interconnections such as access are to transmit voice, business such as data.Transmission equipment and switch, the 2M of base station butt joint general earlier with both sides separately the 2M interface of equipment introduce distributing frame by cable, realize that by the wire jumper of distributing frame both sides' transmitting-receiving links to each other again.If switch; equipment such as base station are not opened operation; the engineering staff can use the transmitting-receiving short circuit of wire jumper with the 2M interface of transmission equipment usually; be about to the 2M interface from ring avoiding the 2M interface loss of signal alarm (PPI-LOS) to occur, but the 2M interface of two websites of business intercommunication all from encircle the time 2M interface may occur the physical interface alarm at random and indicate (PPI-AIS).Show that business breaks down and need in time to handle if PPI-AIS alarm appears in the 2M mouth of the transmission speech business of using, but if circuit obviously need not handled from this alarm that ring causes, therefore effectively avoid the 2M interface under the ring situation, to occur the PPI-AIS alarm at random and help accurate positioning service fault, alleviate attendant's burden, improve attendant's operating efficiency.

Summary of the invention

The object of the present invention is to provide 2M interface in a kind of SDH of elimination equipment when encircling, to occur the method for PPI-AIS alarm at random, that is to say, the PPI-AIS alarm when encircling, do not occur at the equal circuit of 2M interface of two light synchronizing digital transmission equipments of intercommunication at circuit.

The 2M interface method that PPI-AIS alarms occurs at random at circuit in a kind of SDH of elimination equipment that the present invention proposes when encircling, it is characterized in that: when the PPI-LOS alarm is from having to do not having, forces on the 2M branch road, to talk about or talk about down direction and insert one section pseudo noise code to eliminate the transmission of complete ' 1 ' code stream.

Wherein, if 2M mapping chip provides pseudo-noise code generator, when the 2M input signal grows out of nothing, can on the 2M branch road, talk about or talk about down direction and produce pseudo noise code by the register of configuring chip.

Wherein, shine upon the programmable logic cells that chip chamber adding one is used to insert pseudo noise code at 2M interface chip and 2M, clock with the output of 2M interface chip, data and LOS index signal are introduced programmable logic cells, can insert pseudo noise code automatically by programmable logic cells when the 2M input signal grows out of nothing.

Wherein, if having shielded the PPI-AIS alarm of 2M interface unit, the attendant do not start the insertion operation of pseudo noise code.

The present invention has avoided the unnecessary PPI-AIS warning information of 2M interface by the transmission that the insertion pseudo noise code has been eliminated all-ones stream.

Description of drawings

Fig. 1 is the schematic diagram that produces principle at random when the PPI-AIS alarm when encircling of 2M interface;

Fig. 2 is that the module of transmission equipment 2M interface of the present invention constitutes schematic diagram;

Fig. 3 is the flow chart that inserts pseudo noise code.

Embodiment

Describe the specific embodiment of the present invention in detail below in conjunction with accompanying drawing.

Physical interface alarm indication is that the 2M code stream of PPI-AIS alarm expression input is complete ' 1' sign indicating number, because speech business is a framing signals, fixedly frame head is arranged, therefore, even the voice channel free time, a frame totally 256 bits can not occur entirely yet ' the 1' sign indicating number, thus the 2M passage when voice signal if PPI-AIS alarm expression business break down, need in time to handle, the 2M interface circuit principle of PPI-AIS alarm occurs and sees Fig. 1 when encircling.

Linking to each other in light path, may to occur the mechanism of PPI-AIS alarm when encircling at random as follows for the equal circuit of 2M interface of two light synchronizing digital transmission equipments of business intercommunication: as shown in Figure 1, A station signal 2M interface does not have circuit from ring, B station 2M interface circuit is from ring, this moment, A station 2M interface was in the dropout state, focus automatically and insert promptly complete ' 1 ' yard of ais signal on the line direction, B station 2M mouth receives after outside line sends it back the A station again from ring, and the output of A station 2M interface is ais signal.When the 2M interface at A station also passes through the wire jumper loopback, if contact does not physically make signal produce distortion, then random signal will be transmitted in this closed-loop path all the time, if the signal that transmits in this closed-loop path is complete ' 1 ' yard, the PPI-AIS alarm all can appear in the 2M mouth of two ends SDH equipment, if be non-complete ' 1 ' yard, then the PPI-AIS alarm can not appear in two ends, therefore causes the uncertainty of PPI-AIS alarm.If force in this case on the 2M branch road, to talk about or talk about direction down and insert the transmission that one section pseudo noise code just can be eliminated complete ' 1 ' code stream, also just can stably eliminate PPI-AIS and alarm.

Pseudo noise code be inserted with dual mode, a kind of is that software mode inserts, if 2M mapping chip provides pseudo-noise code generator, when the 2M input signal grows out of nothing, can on the 2M branch road, talk about or talk about down direction and produce pseudo noise code by the register of configuring chip, cancel subsequently at once.

Another kind is that hardware mode inserts, (the words direction is inserted pseudo noise code on the 2M branch road) specifically as shown in Figure 2, the 2M signal of branch road input has been finished clock recovery and code conversion by the 2M interface chip, clock with the output of 2M interface chip, data and LOS index signal are introduced programmable logic cells, when the 2M input signal grows out of nothing, can insert the pseudo noise code of very short time automatically, need not software and participate in by programmable logic cells.Because input signal also grew out of nothing when normal 2M service inserted, and can trigger the insertion of pseudo noise code equally, therefore business can finish the normal connection in back in the insertion process of pseudo noise code.

The difficulty of more above-mentioned two kinds of methods, the pseudo noise code of software mode is inserted and is realized easily and hardware mode is difficult, but the realization of hardware mode has following advantage, being inserted into the process time of cancelling pseudo noise code very short is microsecond level (less than 100 microseconds), and software mode is owing to be subject to the interior microprocessor speed of 2M interface unit, being inserted into the process time of cancelling pseudo noise code is Millisecond (less than 5 milliseconds), and the time normal time of connecting of short meaning 2M service is also shorter.The pseudo noise code frequency of software mode insertion is the interior Reference clock frequency of 2M interface unit and the frequency-independent of 2M input signal on the other hand, and the hardware mode utilization is inserted the 2M clock recovery that pseudo noise code helps receiving terminal like this from 2M input signal clock recovered.

The flow chart of whole insertion process is seen Fig. 3, does not start the insertion operation of pseudo noise code if the attendant has shielded the PPI-AIS alarm of 2M interface unit.

The above is preferred embodiment of the present invention only, is not limited to the present invention, all any modifications of being made within the present invention spirit and principle, is equal to replacement and improvement etc., all is contained within protection scope of the present invention.

Claims

1. eliminate 2M interface in the SDH equipment and when encircling, occur the method for PPI-AIS alarm at random for one kind at circuit, it is characterized in that: when the PPI-LOS alarm is from having to do not having, forces on the 2M branch road, to talk about or talk about down direction and insert one section pseudo noise code to eliminate the transmission of complete ' 1 ' code stream;

Wherein, insert pseudo noise code by software or hardware mode, software mode inserts pseudo noise code, if 2M mapping chip provides pseudo-noise code generator, the register by configuring chip when the PPI-LOS alarm is from having to do not having produces pseudo noise code with software mode in the words or the following words direction of 2M branch road;

Hardware mode inserts pseudo noise code, shine upon the programmable logic cells that chip chamber adding one is used to insert pseudo noise code at 2M interface chip and 2M, clock with the output of 2M interface chip, data and PPI-LOS index signal are introduced programmable logic cells, insert pseudo noise code automatically by programmable logic cells when the PPI-LOS alarm is from having to do not having.

2. the method for claim 1 is characterized in that: do not start the insertion operation of pseudo noise code if the attendant has shielded the PPI-AIS alarm of 2M interface chip.