KR20060064244A - Apparatus and method for processing of variable time slot of voice subscriber in wdm-pon system - Google Patents

Abstract

An object of the present invention is to provide an apparatus and method for processing a variable time slot of a voice subscriber in a WDM-PON system. The present invention processes a voice signal of a subscriber telephone by receiving a signal indicating an off-hook state from a voice processing unit. A control unit for outputting a three-state control signal to the processing unit to allocate a timeslot; And providing a voice service to the subscriber telephone by informing the controller of an off-hook status of the subscriber telephone, and receiving a tri-state control signal of the controller and assigning a time slot to process the voice signal of the subscriber. In order to perform data transmission / reception, time slots can be variably allocated so that the largest number of voice subscribers can be processed using the minimum TDM stream.

Description

Apparatus and method for processing of variable time slot of voice subscriber in WDM-PON system}

1 is a block diagram of a fixed time slot processing apparatus for a voice subscriber using a UDLC method in a conventional WDM-PON system.

2 is a block diagram of a fixed time slot processing apparatus for a voice subscriber using an IDLC scheme in a conventional WDM-PON system.

3 is a detailed block diagram of a controller and a voice processing unit in FIGS. 1 and 2;

4 is a block diagram of a fixed time slot processing apparatus of a voice subscriber in a WDM-PON system to which the present invention is applied;

5 is a block diagram of a fixed time slot processing apparatus for a voice subscriber in a WDM-PON system according to the present invention;

FIG. 6 is a detailed block diagram of the voice processing unit in FIG. 5;

7 is a flowchart illustrating a method for processing a fixed timeslot of a voice subscriber when calling in a WDM-PON system according to an embodiment of the present invention;

8 is a flowchart illustrating a method for processing a fixed timeslot of a voice subscriber when an incoming call is received in a WDM-PON system according to another embodiment of the present invention.                 

Fig. 9 is a waveform diagram showing an example of time slot assignment used in the present invention.

Explanation of symbols on the main parts of the drawings

10: COT 11: control unit

12: FXO 20: RT

21: control unit 22: FXS

23: DS0 switch 30: control unit

40: sound processing unit 41 to 43: slot

44 ~ 46: 3 status buffer 50: Subscriber phone

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to time slot processing of voice subscribers in a WDM-PON (Wave-length Division Multiplexing-Passive Optical Network) system, and more particularly to provide voice services to subscriber phones. The time slot of the voice subscriber in the WDM-PON system can be variably allocated to perform the transmission and reception of the maximum number of voice subscribers using a minimum time division multiplexing stream (TDM). A variable timeslot processing apparatus and method are provided.

In general, WDM (wavelength division multiplexing) is a technology that loads several types of data from different places together in one optical fiber, and improves communication capacity and speed. Each data is transmitted at its own wavelength, which can carry up to 80 wavelengths or data channels on a single fiber. Different data at different rates, such as Internet data, synchronous optical network (SONET) data, and asynchronous transfer mode (ATM) data, can be transmitted together.

In addition, PON (Passive Optical Network) is a system that delivers signals to end users through optical cable network. Depending on where the PON is terminally terminated, the system may include FTTC (Fiber To The Curb), FTTB (Fiber To The Building) or FTTH (Fiber To The Home) Divided into.

These PONs consist of one Optical Line Termination (OLT) installed in a telecommunications company and a number of Optical Network Units (ONUs) installed near subscribers, and typically up to 32 ONUs can be connected to one OLT. In PON, passive, or “passive,” means that once a signal begins to pass through the network, power energy or active electronics are no longer needed for optical transmission.

Therefore, the configuration and operation of the prior art in the WDM-PON system combined with WDM and PON is as follows.

1 is a block diagram of a fixed time slot processing apparatus for a voice subscriber using a universal digital loop carrier (UDLC) scheme in a conventional WDM-PON system.

Here, reference numeral 10 is a central office terminal (COT), 11 is a control unit in the COT (10), and 12 is a Foreign Exchange Office (FXO) in the COT (10).

Reference numeral 20 denotes a remote terminal (RT), 21 denotes a control unit in the RT 20, and a FXS (Foreign Exchange Station) in the RT 20.

2 is a block diagram of a fixed time slot processing apparatus for a voice subscriber using an integrated digital loop carrier (IDLC) scheme in a conventional WDM-PON system.

Here, reference numeral 10 denotes a COT, and 11 denotes a control unit in the COT 10.

Reference numeral 20 is an RT, 21 is a control unit in the RT 20, and an FXS in the RT 20.

FIG. 3 is a detailed block diagram of the controller and the voice processing unit in FIGS. 1 and 2.

Here, reference numeral 21 is a control unit, 22 is an FXS, and 23 is a plurality of switches in the control unit 21. In addition, the control unit 21 and the FXS 22 transmit an FP (Frame Pulse) frame and a PCMCLK (PCM data clock) transmission line, and up and down TDM stream transmission lines for a plurality of subscribers. Is connected.

Therefore, the conventional subscriber device in the WDM-PON uses two methods to provide a voice service to the subscriber.

The first is to provide a fixed time slot to the subscriber by using the UDLC (Universal Digital Loop Carrier) method as shown in Figure 1 to provide the voice service to the subscriber, the second is to use the Integrated Digital Loop Carrier (IDLC) method To provide the subscriber with voice services.                         

The configuration of the UDLC method as shown in FIG. 1 is largely composed of a COT 10 and an RT 20, so that the FXT 12, which is a voice processing unit, also enters the COT 10, and the FXS (which is a voice processing unit) is also included in the RT 20. 20) is used to perform voice processing using both fixed timeslots.

In addition, the configuration of the IDLC method as shown in FIG. 2 is composed of a COT 10 and an RT 20 as in FIG. 1. The difference is that the COT 10 does not need to have a voice processing unit. Only the RT 20 contains the voice processing unit FXS 22 to enable subscriber voice service.

Thus, the control unit 11 changes the portion of the PCM (Pulse Code Modulation) data received from the speech processing unit into an optical signal for transmitting to the RT 20 and the signal received from the optical signal back to the PCM data. Part is included.

The FXO 12 is also an audio processing unit of the COT 10. The FXO interface is then connected to a public switched telephone network (PSTN) switchboard, which is the interface provided by conventional telephones. In addition, FXO 12 refers to a trunk line, that is, a loop or DID / DOD (Direct Inward Dialing / Direct Outward Dialing).

The FXS 22 is also an RT 20 voice processing unit. So the FXS interface connects directly to a standard phone and provides ring tone, voltage, dial tone, and more. In addition, the FXS 22 refers to an extension, that is, a DLI (Data Link Interface) or SLC (Subscriber Loop Carrier).

The timeslot refers to a section in which voice data of one subscriber can be loaded.

Referring to the operation of the prior art in more detail as follows.

First, in the UDLC method, the PSTN line of the exchanger is directly connected to the FXO 12 of the COT 10 to provide subscriber service through the COT 10 and the RT 20. In the IDLC method, the V5.2 E1 line of the exchanger is used. It is connected to the COT (10) to provide subscriber services through the COT (10) and RT (20).

Of course, both of these methods perform the audio signal and the signal processing in the FXS 22 and transmit them to the control unit 21. In the switch 23 of the control unit 21, the respective voice processing units FXO and FXS are used. The voice service is provided by sending and receiving voice signals using timeslots assigned to each subscriber through UP and DOWN TDM STREAM connected to each other.

However, this conventional technology has the following problems.

That is, in the prior art, since the number of the voice processing units has to provide the number of TDM streams and the switch 23 for processing the voice signal and the signal again has to enter that number, additional components are generated and the cost increases. In addition, there is a problem that a large load of the processing part in the software for processing it is required.

Accordingly, the present invention has been proposed to solve the above-mentioned general problems, and an object of the present invention is to allow variable allocation of time slots when performing data transmission / reception to provide a voice service to a subscriber telephone. An apparatus and method for processing a variable timeslot of a voice subscriber in a WDM-PON system capable of processing a maximum number of voice subscribers using a TDM stream of the present invention.

In order to achieve the above object, a variable time slot processing apparatus of a voice subscriber in a WDM-PON system according to an embodiment of the present invention,

A control unit configured to receive a signal indicating an off-hook state from a voice processing unit, process a voice signal of a subscriber telephone, and output a tri-state control signal to the voice processing unit to allocate a time slot; And a voice processing unit for notifying an off-hook state of the subscriber telephone to the control unit, receiving a tri-state control signal of the control unit, and assigning a time slot to process a voice signal of the subscriber.

In order to achieve the above object, a variable time slot processing method of a voice subscriber in a WDM-PON system according to an embodiment of the present invention,

If off-hook of the subscriber telephone, storing in the register of the voice processing unit; A second step of allocating a timeslot to a subscriber port when the controller detects a state change by reading a register of the voice processing unit at a predetermined time after the first step; A third step of loading data of the subscriber telephone into the allocated time slot after the second step and transmitting the data to the controller; And a fourth step of providing a voice service by processing the data in the third step to generate and transmit an optical signal after the third step.

Hereinafter, an embodiment according to the present invention, a variable time slot processing apparatus for a voice subscriber in a WDM-PON system, and a technical concept of the method will be described with reference to the accompanying drawings.

Figure 4 is a block diagram of a fixed time slot processing apparatus of a voice subscriber in the WDM-PON system to which the present invention is applied.

Here, reference numeral 10 denotes a COT, and 11 denotes a control unit in the COT 10.

Reference numeral 20 denotes an RT, 21 denotes a control unit within the RT 20, and a voice processing unit within the RT 20.

FIG. 5 is a block diagram of a fixed time slot processing apparatus for a voice subscriber in the WDM-PON system according to the present invention. FIG. 6 is a detailed block diagram of the voice processing unit in FIG.

As shown in the drawing, a signal indicating an off-hook status is received from the voice processing unit 40 to process a voice signal of the subscriber telephone 50, and the tri-state is input to the voice processing unit 40. A control unit 30 for outputting a control signal and allocating a timeslot; The voice processing unit 40 for notifying the off-hook state of the subscriber telephone 50 to the control unit 30 and receiving a tri-state control signal from the control unit 30 and assigning a time slot to process the voice signal of the subscriber It is configured to include.

In the above, the voice processing unit 40 buffers and processes the TDM streams received from the plurality of slots 41 to 43 according to the three-state control signal from the control unit 30. It is configured to include.                     

Here, FP is a frame pulse, PCMCLK is a PCM DATA CLOCK, an up TDM stream is a voice signal given from the voice processing unit 40 to the controller 30, and a Down TDM stream is a voice unit from the controller 40. Is a voice signal.

In addition, the slot 1, 2, 3 tri-state control is a control signal used to make common signal lines connected to the self provided in slots 1, 2, 3 into tri-state.

7 is a flowchart illustrating a method for processing a fixed timeslot of a voice subscriber at the time of origination in a WDM-PON system according to an embodiment of the present invention.

As shown therein, when the subscriber telephone 50 is off-hook, a first step (ST1) (ST2) for storing in the register of the voice processing unit (40); A second step (ST3) (ST4) of allocating a time slot to a subscriber port when the controller (30) reads a register of the voice processing unit (40) at a predetermined time after the first step and detects a state change; A third step (ST5) of carrying the data of the subscriber telephone (50) in the allocated time slot after the second step and transmitting the data to the controller (30); After the third step, the control unit 30 includes a fourth step (ST6) (ST7) for processing the data to generate and transmit the optical signal to provide a voice service.

8 is a flowchart illustrating a method of processing a fixed timeslot of a voice subscriber when receiving a call in a WDM-PON system according to another embodiment of the present invention.

As shown here, when there is an incoming call to the subscriber telephone 50, an eleventh step (ST11) (ST12) of analyzing the received message using the V5.2 protocol; After the eleventh step, a twelfth step (ST13) (ST14) of supplying a ring to the subscriber phone (50) is performed by writing a specific value in a register of the corresponding port of the voice subscriber phone (50).

In the fixed time slot processing method of the voice subscriber when the incoming call is received in the WDM-PON system, when the off-hook is detected from the subscriber telephone 50 after the twelfth step, the specific time of the TDM stream coming down from the control unit 30 is determined. The method further includes a thirteenth step (ST15) (ST16) of converting PCM data contained in a slot into an analog signal and providing the same to the subscriber telephone 50.

An apparatus and method for processing a variable timeslot of a voice subscriber in a WDM-PON system according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.

First, the present invention is intended to handle as many voice subscribers as possible by using a minimum TDM stream by allowing time slots to be variably allocated when performing data transmission / reception to provide voice services to subscriber telephones.

Thus, in the present invention, the RT 20 of the subscriber device that processes the capacity of a certain number of subscribers uses a single Tx stream, which is common between the control unit 30 and the voice processing unit 40, to be fixed. Provide voice services to a large number of subscribers.

Of course, in this case the aggregation ratio of the device must be specified in the device specification.

Therefore, in order to enable voice subscribers to enable voice service through the public telephone network, the voice processing unit 40 converts the analog voice heard through the subscriber phone into a PCM signal and converts it into digital data, or It should be possible to convert the PCM data into a voice analog signal and send it to the subscriber telephone 50.

In addition, it should be able to check whether the subscriber has listened to the telephone, and send off-hook information to the control unit 30. In the case where the incoming call is received to the subscriber telephone 50, the subscriber telephone 50 rings. Should be able to provide

In order to send the PCM data generated in the voice processing unit 40 to the exchange, first, a signal must be transmitted through a TDM stream connected between the control unit 30 and the voice processing unit 40.

Here, as in the prior art, a large number of timeslots are required to provide a service by allocating one timeslot to each subscriber. To this end, the control unit includes several TDM streams and a chipset capable of processing the same. ) Should enter. This soon leads to unnecessary costs and software overhead.

In reality, when providing a voice service to a subscriber, it is not necessary to provide a single fixed timeslot to the subscriber.

This is because the subscriber does not use much more time than the voice service.

Therefore, it is possible to design the device more economically and efficiently if a certain number of timeslots are allocated to one subscriber and more subscribers can occupy the timeslots only when they want to use voice service.

For example, to provide voice service to 100 subscribers, only one common UP and DOWN TDM stream is connected between the control unit 30 and the voice processing unit 40.

If there are about 100 subscribers, about 3 slots may be mounted in the voice processing unit 40.

In other words, there is only one TDM stream for transmitting and receiving voice data between the control unit 30 and the three slots of the voice processing unit 40 to enable voice services of all subscribers.

To this end, the voice processing unit 40 includes three-state buffers 44 to 46 which perform three-state buffering on three slots.

The operation of the present invention will be described by dividing into 1) when the subscriber makes a call and 2) when the subscriber makes a call.

First, when the subscriber wants to talk first, the subscriber picks up the handset.

When the subscriber picks up the receiver, the voice processing unit 40 detects an off-hook signal and stores the value in the register of the voice processing unit 40.

Then, the control unit 30 reads this register every predetermined time, and if there is a change in the state of the value, checks the port information of the subscriber station 50, and then corresponds to the port that is attempting the call of the voice processing unit 40. The register writes the value to use the timeslot of the TDM stream.

Accordingly, the voice signal received from the subscriber telephone 50 is converted into a digital signal in the internal logic of the voice processing unit 40 according to the value of the register, and then loaded into the corresponding time slot and sent to the control unit 30. .

The voice data sent to the control unit 30 is muxed with other data and sent to the exchange to provide a voice service to the subscriber.

The value written to the register on that subscriber's port is cleared at the moment the subscriber ends the call.

Here, while this subscriber is using the corresponding timeslot, the other slot of the voice processing unit 40 should not carry voice data of another subscriber with respect to the corresponding timeslot of this TDM stream which is commonly used. Make the corresponding timeslot state of this common signal line tri-state.

Otherwise, the data of the timeslot being used may overlap with the voice signals coming from the other slots of the voice processing unit 40 and the data may be broken due to the change of the signal level.

If the other subscriber wants to make a call after the subscriber has finished, the subscriber may be provided with voice services using this timeslot. Of course, if you have another empty timeslot, you can use that timeslot.

Secondly, contrary to the above, the operation of the incoming call coming to the subscriber is described as follows.

First, when the exchange comes to this device from the exchange side, the control section analyzes the message using the V5.2 protocol and writes a specific value to the register of the corresponding port of the voice subscriber to provide a ring to the subscriber.

In addition, by providing a value to use a specific timeslot in the register of the corresponding port, the subscriber converts the PCM data contained in a specific timeslot of the TDM stream coming down from the control unit 30 to an analog signal when the subscriber listens to the receiver. Provided by phone to make a call.

In this case, since it is the DOWN side, it is irrelevant to each signal line, and the voice processing unit 40 processes data coming into the corresponding port under the control of the controller 30.

Fig. 9 is a waveform diagram showing an example of time slot assignment used in the present invention.

Thus, when the subscriber lifts up the telephone 50, the voice processing unit 40 changes the state of the register of the internal logic to indicate how many times the port has been off-hook.

After that, the controller 30 reads the register every predetermined time, and if there is a change in the state, checks the time slot currently being used, and then corresponds to the corresponding voice processing unit 40 that is attempting to call information on the empty time slot. It is provided in the register of the port.

The port assigned with the timeslot encodes the analog voice signal received from the subscriber telephone 50 by the internal logic of the voice processing unit 40, converts it into PCM data, and loads the data into the allocated timeslot to the controller. Will be sent.

Then, the control unit 30 processes the data into an optical signal and then transmits the signal to the COT 10 to exchange signals with the exchange so that the voice service is provided to the subscriber.

Here, the TDM stream used by the voice processing unit 40 to send a voice signal to the control unit 30 has 32 timeslots (this can be changed at design time in the device, which is set to 32 here).

So, in the example of FIG. 9, since slot1 and PORT1 subscribers have attempted a call, TS0 (time slot 0 times) of a TDM stream connected to SLOT1 in an UP TDM stream commonly connected to three ports of the voice processing unit 40 is used. ) Should only be loaded (of course other empty timeslots).

In other SLOTs 2 and 3, the signal corresponding to time slot 0 is controlled to be tri-stated by the internal logic of the voice processing unit 40.

By doing so, the voice data can be properly transmitted to the control unit 30 without being broken, thereby enabling the voice service.

As described above, the present invention allows a variable number of timeslots to be allocated when performing data transmission / reception in order to provide a voice service to a subscriber telephone, thereby handling as many voice subscribers as possible using a minimum TDM stream.

Although the preferred embodiment of the present invention has been described above, the present invention may use various changes, modifications, and equivalents. It is clear that the present invention can be applied in the same manner by appropriately modifying the above embodiments. Accordingly, the above description does not limit the scope of the invention as defined by the limitations of the following claims.

As described above, the apparatus and method for processing a variable time slot of a voice subscriber in the WDM-PON system according to the present invention can be used to variably allocate a time slot when performing data transmission / reception to provide a voice service to a subscriber telephone. This allows the maximum number of voice subscribers to be processed using the minimum TDM stream.

In fact, when providing a voice service to a subscriber, it is not necessary to provide a subscriber with one time slot. This is because the subscriber does not use much more time than the voice service.

Therefore, rather than allocating one timeslot to one subscriber, a certain number of timeslots and more subscribers use a common signal line to provide voice services, and it is more economical to make it possible to occupy the timeslot variably. And efficient device design is possible.

Claims (5)

A control unit configured to receive a signal indicating an off-hook state from a voice processing unit, process a voice signal of a subscriber telephone, and output a tri-state control signal to the voice processing unit to allocate a time slot; In the WDM-PON system characterized in that it comprises a voice processing unit for informing the control unit of the off-hook status of the subscriber telephone, receiving a tri-state control signal of the control unit and assigning a time slot to process the voice signal of the subscriber; Variable time slot processing apparatus of the voice subscriber. The method of claim 1, wherein the voice processing unit, And a plurality of three-state buffers configured to buffer and process TDM streams received from the plurality of slots according to three-state control signals from the control unit. If off-hook of the subscriber telephone, storing in the register of the voice processing unit; A second step of allocating a timeslot to a subscriber port when the controller detects a state change by reading a register of the voice processing unit at a predetermined time after the first step; A third step of loading data of the subscriber telephone into the allocated time slot after the second step and transmitting the data to the controller; And a fourth step of providing a voice service by processing data in the control unit to generate and transmit an optical signal after the third step, and to perform a voice service in the WDM-PON system. . An eleventh step of analyzing the incoming message using the V5.2 protocol when there is an incoming call to the subscriber telephone; And the twelfth step of supplying a ring to the subscriber phone by writing a specific value to a register of a corresponding port of the voice subscriber phone after the eleventh step. Slot processing method. 5. The method of claim 4, wherein the fixed time slot processing method for the voice subscriber when the incoming call is received in the WDM-PON system comprises: detecting a off-hook from the subscriber telephone after the twelfth step; And a thirteenth step of converting the PCM data contained in the analog signal into an analog signal and providing the same to the subscriber telephone.

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