JP2727709B2 - PCM channel tandem connection method - Google Patents

Description

The present invention relates to a PCM channel tandem connection system for a PCM code communication system.

[Conventional technology]

In the conventional PCM channel tandem connection method, the transmission side performs PCM-voice conversion and extraction of signaling information, and the reception side performs voice connection and performs voice-PCM conversion and insertion of signaling information again. I was

[Problems to be solved by the invention]

In the conventional PCM channel tandem connection method described above,
The transmitting side performs PCM-voice conversion and extraction of signaling information, and the receiving side adopts a tandem connection system in which voice connection is performed and voice-PCM conversion and signaling information are inserted again, so that PCM-voice and voice- There is a disadvantage that voice quality is significantly deteriorated by the conversion of PCM.

[Means for solving the problem]

The PCM channel tandem connection method according to the present invention includes a channel interface circuit that receives an interface with a demultiplexer and a clock, a speed conversion circuit that performs speed conversion of transmission-side data and reception-side data, and the transmission-side data in a bipolar format. A decoding circuit for extracting transmission signaling information by a violation code and converting a bipolar signal into a unipolar signal, and a code circuit for converting the reception side data into a bipolar signal and adding reception signaling information by generating a bipolar violation. ing.

〔Example〕

 Next, the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing an example of a PCM tandem connecting device in FIG. 1, and FIG. 3 is a fast-in-fast receiver on the receiving side in FIG. FIG. 4 is a diagram showing the relationship between the input / output data of the out-memory and the clock, FIG. 4 is a diagram showing an example of the occurrence of bipolar violation on the receiving side, and FIG. 5 is a drawing of the signaling extraction of the PCM tandem connection device in FIG. FIG. 6 is a diagram showing a relationship between input / output data and a clock of the fast-in / fast-out memory on the transmitting side in FIG.

In FIG. 1, in the present embodiment, a PCM tandem connection device 3 for mutually transmitting and receiving data and a PCM tandem connection device 3 are provided.
A separation multiplexing device 2a, 2b for supplying a clock by interfacing with the tandem connection device 3 and separating and multiplexing 64 Kbps data of 30 channels, and an intra-station clock supply device 1 for supplying an intra-station clock to the demultiplexing devices 2a, 2b. It has and is constituted.

In FIG. 2, the PCM tandem connection device 3 shown in FIG. 1 includes a channel interface circuit (hereinafter, referred to as CHINF) 31 for interfacing with the demultiplexing / multiplexing device 2a (or 2b) and receiving an intra-station clock, and transmitting-side data. Fast-in fast-out memory (hereinafter referred to as FI)
FOM) 32 and F which performs speed conversion of the receiving data
IFOM33, a decoder circuit (hereinafter referred to as DECODE) 34 for extracting transmission signaling information from the transmission data in bipolar format by a violation code and converting the bipolar signal of the input signal into a unipolar signal, and converting the reception data into a bipolar signal. A mode circuit (hereinafter referred to as CODE) that converts and adds reception signaling information when a violation occurs.
35).

Next, the operation of the PCM tandem connection device shown in FIG. 2 will be described.

First, the operation on the receiving side will be described with reference to FIGS.
This will be described with reference to FIGS.

The CHIHF 31 receives the reception data 41 separated for each channel from the demultiplexer 2a (or 2b), and writes the received data 41 to the FIFOM 33. The read clock 39 of the FIFOM 33 is given from the CHINF 31 in synchronization with the clock supply device 1 in the office, and the reception data 41 is
It is converted to the speed of the read clock 39 from CHINF31. The input / output data 41 and 40 of the FIFOM33 and the clock in the station
FIG. 3 shows the relationship of 39.

The output data 40 of the FIFOM 33 is input to the CODE 35. CODE3
In step 5, the receiver data 40 is converted to a bipolar signal,
The data is transmitted to the opposite PCM tandem connection device 3 shown in FIG.
At this time, it is necessary to insert the received signaling information. In this embodiment, the received signaling information is added by bipolar violation. That is, any one of the 8 bits is violated by the received signaling signal 42, and the on / off state of the signaling is displayed with or without the violation. FIG. 4 shows an example of occurrence of bipolar violation.

Next, the operation on the transmitting side will be described with reference to FIGS.
This will be described with reference to FIG. 6 and FIG.

The bipolar signal from the opposing PCM tandem connection device 3 shown in FIG. DECODE34 performs bipolar violation monitoring and bipolar / unipolar conversion. The 8-bit data of one time slot is synchronized with the intra-station 8 kHz clock, and the transmission signaling information is extracted by monitoring the bipolar violation of the transmission-side data, and the transmission signaling signal 43 is transmitted to the CHINF3.
Send to 1. FIG. 5 shows an example of signaling extraction.

The DECODE 34 writes the transmission data 36 to the FIFOM 32 using the bipolar / unipolar conversion. The CHINF 31 divides the data on the transmission side at the speed of the transmission clock 8 of the demultiplexer 2 a
Read from 2. FIG. 6 shows the relationship between the input / output data of the FIFOM 32 and the clock.

The CHINF 31 inserts signaling information in accordance with the signaling pulse from the demultiplexer 2a and sends out the signal to the demultiplexer 2a.

〔The invention's effect〕

As described above, the present invention provides a channel interface circuit for interfacing with a demultiplexer and a clock supply, a speed conversion circuit for performing speed conversion of transmission-side data and reception-side data, and a biometric conversion method for transmitting data in bipolar format. PCM by having a decoding circuit that converts a bipolar signal from which transmission signaling information is extracted by a translation code into a unipolar signal, and a code circuit that converts reception-side data into a bipolar signal and adds reception signaling information by generating a bipolar violation. Since tandem connection of signaling and voice can be performed without converting a signal to voice, there is an effect that deterioration of reproduced voice, which is a problem in the conventional tandem connection method, can be reduced. Installation since there is no special additional connection part to the connection method also becomes a simple effect.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, FIG. 2 is a block diagram showing an example of a PCM tandem connection device in FIG. 1, and FIG. 3 is a fast-in-fast receiver on the receiving side in FIG. FIG. 4 is a diagram showing the relationship between the input / output data of the out-memory and the clock, FIG. 4 is a diagram showing an example of the occurrence of bipolar violation on the receiving side, and FIG. 5 is a signaling extraction of the PCM tandem connection device in FIG. FIG. 6 is a diagram showing the relationship between the input / output data of the fast-in / fast-out memory on the transmitting side in FIG. 2 and the clock. 1 ... intra-station clock supply device, 2a, 2b ... demultiplexing device, 3 ... PCM tandem connection device, 31 ... channel interface circuit (CHINF), 32, 33 ... fast-in fast-out memory (FIFOM), 34 ...... Decoding circuit (DEC
ODE), 35… Code circuit (CODE), 36… Signaling extraction signal, 37… Transmission signal, 38… Write clock, 39… Read clock, 40… Received audio signal, 41
...... Reception signal, 42 ... Reception signaling signal, 43 ... Transmission signaling signal.

Claims (1)

(57) [Claims] 1. An interface with a demultiplexer and a channel interface circuit receiving a clock supply, a speed conversion circuit for performing speed conversion of transmission side data and reception side data, and a violation code from the transmission side data in a bipolar format. A PCM, comprising: a decoding circuit that extracts transmission signaling information and converts a bipolar signal into a unipolar signal; and a code circuit that converts the reception side data into a bipolar signal and adds reception signaling information by generating bipolar violation. Channel tandem connection method.