KR19990074377A - Internet dial-up circuit of private exchange - Google Patents

Abstract

The present invention provides an Internet dial-up circuit for enabling an Internet telephone call in a private switching system. Accordingly, the present invention is characterized in that it is an Internet access circuit of a private exchange which is mounted inside a private exchange and enables voice telephone compression of the PCM encoded voice data and transmitted as voice data via the Internet. Therefore, the present invention is economical because it is possible to make international and long distance calls using only Internet charges because the Internet connection circuit is provided inside the private exchange to make international and long distance calls through the Internet.

Description

Internet dial-up circuit of private exchange

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a private switching system, and more particularly to an Internet dial-up circuit that enables telephone calls over the Internet at a private switching center.

In general, the Internet (INTERNET) connects a large number of networks around the world, and computers of many companies, schools, and government offices are networked around the world. The Internet is capable of transmitting information between various networks using a defined protocol (TCP / IP) for the network, and is open and compatible, and the number of users increases exponentially. In addition, since the Internet establishes a foundation for transmitting various information, various communication services are implemented using the Internet.

Due to the above-mentioned characteristics of the Internet, various communication services are being implemented, and a service for transmitting voice in real time using the Internet has recently been in the spotlight. As an example of such a voice transmission service, the Internet phone service is a technology that enables a phone call through the Internet. The Internet phone service is an advancement in voice processing technology and interworking with general telephone networks. As well as computers connected to the Internet, ordinary telephone users can make international or long distance calls using the Internet. The demand for Internet phone services is expected to skyrocket in the future, as it brings users the advantage of using international and long distance calls with only Internet usage fees.

In addition, as the Internet phone service is activated, it is expected to be used in conjunction with terminals subscribed to the existing general telephone network. Among them, when it is linked with a private exchange used in a general company or an office, the efficiency may be expanded, and thus it will be more and more spotlighted. This is because private exchanges are mainly business facilities of general companies or offices, and international telephones or long distance calls are frequently used in business, which increases the burden of telephone call charges.

However, in the conventional private exchange, there was almost no technology interworking with the Internet, but it was only a limited technology. In addition, in the conventional private exchange, there is a problem in that a separate internet access device must be provided in order to perform a telephone call through the aforementioned Internet.

Accordingly, it is an object of the present invention to provide an internet dial-up circuit which enables a telephone call via the internet itself in a private exchange.

Another object of the present invention is to provide an Internet dial-up circuit for making a long distance or international telephone call through the Internet in a private exchange.

It is still another object of the present invention to provide an Internet telephone access circuit for subscribers of a private exchange to make long distance calls or international calls at low cost.

The present invention for achieving the above object is to receive the coded speech signal from the time switch in a private switch to compress the speech data and transmit it to the Internet, and to convert the compressed speech data transmitted from the Internet into a PCM encoded speech signal It is characterized in that the internal Internet access circuit for implementing a telephone call over the Internet by transmitting to the time switch.

1 is a block diagram of a private exchange system showing a telephone call formation through the Internet to which the present invention is applied.

2 is a block diagram of an Internet dial-up circuit according to an embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First, in the following description of the present invention, if it is determined that a detailed description of a related known function or configuration may unnecessarily obscure the subject matter of the present invention, the detailed description thereof will be omitted. In addition, terms to be described later are defined in consideration of functions in the present invention, which may vary according to the intention or custom of a user or a chip designer, and the definitions should be made based on the contents throughout the present specification.

1 is a configuration diagram of a private exchange system showing a telephone call formation through the Internet to which the present invention is applied.

Referring to FIG. 1, the first private exchange 10 is connected to the Internet 30 through an Internet telephone connection circuit 11 and is connected to a second private exchange 20 through the Internet 30. In addition, the first private exchange 10 is connected to the station subscriber 1 through the subscirber line circuit 12. The first private exchange 10 connects the Internet 30 and the station subscriber 1 to a port connected to the first Internet dial-up circuit 11 by switching between the first Internet dial-up circuit 11 and the first subscriber connection circuit 12. The first private exchange 10 informs the first Internet dial-up circuit 11 of the area code and the extension number through a dual tone modulation frequency (DTMF) or R2 signal through a channel set when the Internet is connected. The first Internet dial-up circuit 11 then allocates a voice channel with the Internet dial-up circuit 21 of the second private exchange 20 via the Internet 30. Therefore, when a voice channel over the Internet between the first private exchange 10 and the second private exchange 20 is allocated, the first internet dial-up circuit 11 transmits the call information to the second internet dial-up circuit 21 to transfer the call information to the second private switch 10. A call path is formed between the extension subscriber 1 and the extension subscriber 2 of the second private exchange 20.

Thus, the extension subscriber 1 of the first private exchange 10 in the area 1 is connected to the Internet 30 by the first Internet dial-up circuit 11, and the extension subscriber 2 of the second private exchange 20 in the area 2 is the second Internet phone. The connection circuit 21 is connected to the Internet. Accordingly, the private exchanges 10 and 20 according to the present invention are connected to the Internet 30 by internal Internet dial-up circuits 11 and 21, respectively, to allow subscribers 1 and 2 to make long-distance or international telephone calls via the Internet 30.

The Internet dial-up circuits 11 and 21 of the private exchange according to the embodiment of the present invention include the control unit 201, the first memory 211, the second memory 212, the third memory 213, the Internet controller 221, and the Internet line driver as shown in FIG. It consists of 225, interrupt controller 231, DMA controller 241, codec unit 250, FIFO260, UART270 and RS232C driver 280.

The Internet dial-up circuit according to the embodiment of the present invention compresses the PCM coded voice signal of an extension subscriber by Codebook Excited Linear Prediction (CELP) encoding and transmits it to the Internet. In addition, the Internet dial-up circuit according to the embodiment of the present invention converts the compressed voice transmitted from the Internet into a PCM code and transmits it to the time switch in the private exchange.

On the other hand, the Internet dial-up circuit according to an embodiment of the present invention converts the signal processing message received from the main processing unit in the private exchange into a message conforming to the message transmission protocol via the Internet and transmits it to the Internet. In contrast, the Internet dial-up circuit according to the embodiment of the present invention converts the signal processing message transmitted from the Internet into a message conforming to its own format in the private exchange and transmits it to the main processor.

Referring to FIG. 2, a microprocessor 210 controls the overall operation of the Internet dial-up circuit in accordance with the present invention via an address / data bus. The first memory 211 may be implemented as a flash memory, and stores a control program for controlling the operation of the Internet dial-up circuit according to an embodiment of the present invention, and the program can be changed during online operation. The second memory 212 is a non-volitile memory and stores data that should be preserved even when power is removed. The third memory 213 provides a data area for executing a program by the microprocessor 210 and temporarily stores a CELP-coded data frame. The internet controller 221 transmits data to the Internet by controlling an internet line driver 225 under the control of the microprocessor 210. The interrupt controller 231 transmits an interrupt signal to the microprocessor 210 when the CELP encoded frame data is generated by the codec unit 250, and transmits an interrupt signal to the microprocessor 210 to inform the controller when the CELP encoded frame data is transmitted to the Internet controller 221. That is, the interrupt controller 231 receives the interrupt signal transmitted from the FIFO260, the codec unit 250, and the Internet controller 221 to control the interrupt service at a predetermined priority. The DMA controller 241 transmits the CELP encoded data frame to the third memory 213. The codec unit 250 includes a plurality of codecs, receives a PCM coded signal from a time switch in a private exchange, converts the signal into a CELP coded signal, and receives a CELP coded signal from the Internet controller 221 and converts the signal into a PCM coded signal. To the time switch. The FIFO260 is a means for communicating a signal processing message with a main processing module (MPM). The UART270 is a MMC monitor connected via the RS232C driver 280, which can monitor the status of Internet dial-up circuits and change operating programs and data.

1 and 2, the operation of the Internet dial-up circuit 11 in the private switch 10 according to the embodiment of the present invention will be described. When the subscriber 1 attempts to make a phone call, the first private exchange 10 switches the time switch through the subscriber connection circuit 12 to connect the subscriber 1 and the Internet dial-up circuit 11. Then, the codec unit 250 of the Internet telephony connection circuit 11 receives the PCM coded signal with each codec from a time switch and converts the signal into a CELP coded signal to generate a CELP coded data frame. The CELP encoded data frame is generated, and the codec unit 250 transmits an interrupt signal to the microprocessor 210 through the interrupt controller 231. Upon receiving the interrupt signal, the microprocessor 210 controls the DMA controller 241 to transmit the generated CELP encoded data frame to the third memory. The microprocessor 210 makes the data frame in a packet unit suitable for Internet transmission and controls the Internet controller 221 to transmit the data frame packet to the Internet through the Internet line driver 225.

On the contrary, when the Internet controller 221 receives the CELP encoded packet voice data from the Ethernet through the Internet line driver 225, the Internet controller 221 notifies the interrupt controller 231 to apply the interrupt signal to the microprocessor 210. The microprocessor 210 receiving the interrupt signal decompresses the packet of the transmitted CELP-coded packet voice data into a CELP-coded frame and transmits the packet to the codec unit 250. Then, the codec unit 250 converts the transmitted CELP-coded frame into a PCM-coded signal and transmits it to the subscriber 1 through a time switch.

As described above, the present invention has the advantage that subscribers can make international or long distance phone calls at low cost by providing an Internet dial-up circuit in a private exchange. In addition, the present invention can enable the subscriber of the private exchange to connect to the Internet without providing a separate external access device in the private exchange. In addition, since the present invention implements a program memory as a flash memory, it is possible to download a remote program. Therefore, even if a private exchange is installed, program error correction or program version up is possible through the Internet. In addition, the present invention has a similar configuration to the subscriber module of the private switch having a time switch for the circuit-switching method has an advantage that can be easily applied to the existing private switch.

Claims (3)

In the Internet dial-up circuit of a private exchange for connecting to the Internet to provide Internet telephone service to extension subscribers, Receives a voice signal from a predetermined extension subscriber as a PCM coded speech signal from a time switch, converts it into a codebook-excited linear predictive encoded data frame, and transmits it to the Internet, and converts a codebook excitation linear predictive-coded frame transmitted from the Internet into a PCM speech signal. And transmit to the extension subscriber through the time switch. In the Internet dial-up circuit of a private exchange for connecting to the Internet to provide Internet telephone service to extension subscribers, A codec unit for receiving a voice signal from a predetermined extension subscriber as a PCM coded voice signal from a time switch and converting the codebook excited linear predictive coded data frame, and converting the codebook excited linear predictive coded data frame transmitted from the Internet into a PCM voice signal; , An internet controller which transmits the codebook excitation linear prediction hatching data frame converted by the codec unit to the internet, and transmits the data frame transmitted from the internet to the codec unit; An interrupt controller for receiving an interrupt signal transmitted from the codec unit, the main processor, and the Internet controller and controlling an interrupt service according to a predetermined priority; A microprocessor which converts the data frame converted by the codec unit into a packet unit suitable for Internet transmission, decompresses packets of voice data transmitted from the Internet, and transmits them to the codec unit; And a memory for storing a control program for accessing the Internet. The method of claim 2, wherein the memory, A circuit characterized in that the program can be changed during online operation by being implemented as a flash memory.