KR100299566B1 - An mobile call terminal for pstn subscribers - Google Patents

Abstract

The present invention relates to a method and apparatus for connecting a call path when a subscriber of a premise public switched telephone network (PSTN) wants to talk to a subscriber of a mobile communication network. Typically, when an in-house PSTN subscriber calls a subscriber of a mobile communication network, a call is made through a central office line and then through a wireless channel of a cellular / PCS network. In the PSTN network provider, as well as paying a fee to the mobile network operator, the caller has a burden of double paying. In addition, when a failure occurs in the PSTN network due to various causes, a case in which a subscriber of an external mobile communication network cannot be called may occur. Therefore, in the present invention, in order to solve such a problem in the prior art, when a home PSTN subscriber calls a subscriber of the mobile communication network, the subscriber of the mobile communication network is directly called through the device according to the present invention, rather than through the PSTN network. It was made. MCT (Mobile Call Terminal) of the present invention is a MCU (Main Control Unit), POTS Interface (Plain Old Terminal Services Interface), Mobile Phone Interface (Mobile Interface), PSTN interface, PSTN or cellular / PCS switch unit and DTMF It consists of an interface part.

Description

Mobile phone incoming / outgoing agency method for public telephone network subscriber and device therefor {AN MOBILE CALL TERMINAL FOR PSTN SUBSCRIBERS}

The present invention relates to a method for a premise Public Switched Telephone Network (PSTN) subscriber to talk to a subscriber of a mobile communication network. More specifically, the present invention is provided by separating a PSTN line, which is a wired communication network, and a communication path of a mobile communication network from each other. A method and apparatus for enabling a subscriber to make a telephone connection with a subscriber of a direct mobile communication network without going through a PSTN network.

Typically, when a home subscriber calls a subscriber of a mobile communication network, a call is made through a central office line and then through a wireless channel of the mobile communication network. In this conventional method, a fee is paid to a PSTN provider. At the same time, since a fee must be paid to a mobile network operator, a person who attempts to make a call has a problem of paying a double fee. In addition, when a failure occurs in the PSTN due to various causes, there is a problem in that it is impossible to call a subscriber of an external mobile communication network. Therefore, in the present invention, in order to solve the problems in the related art, when the subscriber in the home calls the subscriber of the mobile communication network, the subscriber of the mobile communication network is called directly through the apparatus according to the present invention, not through the PSTN. .

One object of the present invention is to reduce the charges charged to an indoor subscriber by calling the subscriber of the mobile network directly by the device of the present invention, rather than through the PSTN, unlike the conventional method, when the domestic subscriber calls a mobile network subscriber. It is for.

Another object of the present invention is that when a home subscriber calls a mobile network subscriber, unlike in the conventional method, the trunk line connected to the PSTN is broken by causing the subscriber of the mobile network to directly call the subscriber of the mobile network by the apparatus of the present invention, rather than through the PSTN. Even if the mobile communication network subscriber can be called.

1 is a block diagram of an in-house PSTN subscriber's mobile phone incoming / outgoing proxy device according to the present invention.

Fig. 2 is a flowchart when calling a PSTN subscriber or a mobile subscriber from a telephone connected to a mobile telephone incoming / outgoing proxy apparatus of the present invention.

Fig. 3 is a flowchart when a PSTN subscriber or a mobile telephone subscriber calls a telephone connected to the mobile telephone incoming / outgoing agent apparatus of the present invention.

<Description of the symbols in the main part of the drawing>

10: Mobile Call Terminal (MCT)

11: MCU (Main Control Unit)

12: Plain Old Terminal Services (POTS)

13: Mobile Interface Interface

14: PSTN interface unit

15: PSTN or cellular / PCS switch

16: DTMF Interface

The apparatus of the present invention (hereinafter referred to as MCT (Mobile Call Terminal)) 10 includes a main control unit (MCU) 11, a plain old terminal services interface (POTS) 12, a mobile telephone interface unit ( Mobile Interface) 13, PSTN Interface 14, PSTN or Cellular / PCS Switch 15, and DTMF Interface 16.

The MCT device of the present invention may further include a power supply.

With reference to Figure 1 will be described in detail the MCT of the present invention.

The MCU 11 is a main control unit for controlling the MCT 10, which is the apparatus of the present invention, and includes a POTS interface unit 12, a mobile telephone interface unit 13, a PSTN interface unit 14, a PSTN or a cellular / PCS switch unit. 15 and the dual tone multi frequency (DTMF) interface unit 16; In addition, the MCU 11 initializes peripheral chips for CPU initialization and serial communication with the mobile phone interface unit. In addition, the MCU 11 performs number analysis for determining whether the telephone number called by the home subscriber is a PSTN subscriber or a mobile subscriber.

As indicated by reference numeral 20, the POTS interface unit 12 is connected to a telephone (hereinafter referred to as POTS) 22 via a telephone insertion jack. The P0TS interface unit 12 is responsible for the matching function with the POTS 22 connected thereto, and for monitoring the state of the POTS 22 such as off hook and on hook, for example.

The mobile phone interface unit 13 communicates serially with the MCU 11 through, for example, an RS232C protocol. The RS232C protocol is well known in the art and thus a detailed description is omitted. In addition, the mobile telephone interface unit 13 is connected to an RJ-350 jack to which a hands free kit of the mobile telephone 24 is connected via a flat cable. The interface between the mobile phone interface unit 13 and the mobile phone 24 uses a Qualcomm DM protocol (Dual Mode Protocol). Since the DM protocol is known in the art, detailed descriptions are omitted.

Hereinafter, the pin arrangement of the RJ-350 jack to which the hands-free kit is connected will be briefly described.

[Table 1] Pin assignment of PCM type RJ-350 jack and its function

PCM data transmission and reception between the mobile phone 24 and the mobile phone interface unit 13 is performed through pins 6 and 7. A ring message upon incoming call to mobile phone is made through pin 5.

The PSTN interface unit 14 matches with the CO line connected to the PSTN, and forms a communication path with the PSTN.

The PSTN or cellular / PCS switch unit 15 switches the call path to the PSTN interface unit 14 or the mobile telephone interface unit 13 depending on whether the other subscriber called by P0TS is the subscriber connected to the PSTN or the mobile communication network subscriber. Function. The MCU 11, the POTS interface unit 12, the mobile telephone interface unit 13, the PSTN interface unit 14, and the DTMF interface unit 16 are connected to the PSTN or cellular / PCS switch unit 15.

The DTMF interface unit 16 receives a key pad value pressed in the POTS, transmits the value to the MCU 11, and transmits digits from the MCU 11 to the PSTN side.

Hereinafter, referring to FIG. 2, a case of calling a PSTN subscriber or a mobile telephone subscriber from the POTS 22 connected to the mobile telephone call / calling agent of the present invention will be described in detail.

First, the MCU 11 starts a start step indicated by 30. Next, the MCT initialization step 31 is operated. This initialization step 31 includes CPU initialization and initialization for serial communication with the mobile telephone side. The state of the MCT 10 then enters the call waiting state (32). If the POTS 22 off-hook is detected in the call waiting state 32, 33 switches the dial tone to the POTS, switches the DTMF receiver, and then switches to the off-hook mode. Otherwise, it remains in call waiting state 32. Here, instead of switching the dial tone source of the MCT 10 to the POTS 22, the dial tone from the PSTN may be directly connected to the POTS 22.

Subsequently, when the key tone (DTMF digit; key value) pressed in the POTS in the off-hook mode 34 is input via the DTMF interface unit 16 (35), the key value is read and the key value is read as a specific key value (e.g., , '*', '#') (36). In the case of a specific key value, in step 39, a send key request message is generated and transmitted to the mobile phone 24, and the PCM data is switched to pins 6 and 7 described in Table 1 above. do. As an alternative to this switching point, PCM data switching to pins 6 and 7 may be switched in advance. Next, the mobile station enters the call state (40). If the on-hook of the POTS 22 is detected (41) during the call state, the flow returns to step 32.

If it is determined in step 36 that it is not a specific key value (i.e., the numbers '0' to '9'), the flow advances to step 37 to compose a dual mode message. This DM message format is well known in the art and thus a detailed description is omitted. This prepared DM message is transmitted to the mobile telephone 24 connected to the mobile telephone interface unit 13 via a flat cable in step 38. The step then repeats to step 35.

Here, as an alternative method, after analyzing the access code without directly writing the key value pressed in the POTS into a DM message, the counterpart subscriber to call in the POTS is transferred to the PSTN subscriber (for example, region code 032, 062, etc.). DTMF of the DTMF interface unit 16 if the other subscriber is a PSTN subscriber, depending on whether or not the calling party subscriber is called) or a mobile telephone network subscriber (e.g., a caller of the other party starting with 011, 016, etc.). When the key value is transmitted to the PSTN through the sender, and it is determined that the other subscriber is a mobile phone network subscriber or an international telephone subscriber residing in a foreign country (for example, calling a counterpart subscriber starting with 001, etc.). You can also write DM messages only. In this case, if the other party subscriber is a PSTN subscriber, the process proceeds directly to step 40 without performing steps 36 to 39.

In addition, as another alternative method, if the mobile telephone interface unit 13 detects that the mobile telephone 24 is not mounted, the PSTN or cellular / PCS switch unit 15 pre-configures the switching path with the POTS interface unit 12. The PSTN interface unit 14 is connected. In this case, all calls are connected to the PSTN regardless of whether the party to be called is a PSTN subscriber or a mobile phone subscriber. In this case, the process proceeds directly to step 40 in step 35 without executing steps 36 to 39.

The access code analysis method is performed by a numbering plan. For example, when the first digit pressed by the POTS 22 is '0', the counterpart subscriber to call may be determined according to the next second pressed digit. . If the first digit of the first press is not '0', the other party to talk to is a PSTN subscriber. If the first digit is '0' and the second digit is '1', the other party to be called is a subscriber to a mobile phone service company such as, for example, 011, 016. If the first digit is '0' and the second digit is, for example, '2' (Seoul), '3' (Gyeonggi-do), etc., the other party to call is the PSTN subscriber. If the first pressed number is '0' and the second pressed number is also '0', the other party to be called is determined as an international telephone subscriber living in a foreign country.

Hereinafter, with reference to FIG. 3, a case in which a PSTN subscriber or a mobile telephone subscriber calls a telephone connected to the mobile telephone incoming / outgoing proxy apparatus of the present invention will be described.

When a ring signal is detected in step 53, it is determined whether the ring signal is received from the PSTN or the cellular / PCS network (the ring signal from the cellular / PCS network is signaled to pin 5 of Table 1). Is generated (54).

If the ring is received from the PSTN, after the ring signal is transmitted to the POTS 22 (55), it is monitored whether the POTS 22 is off-hook. If the POTS 22 is off-hook (56), the call is transferred (57), and if the ring is disconnected while the ring is being transmitted from the PSTN before the POTS 22 is off-hook, a ring off signal is transmitted to the POTS. After that, the flow returns to step 52. If the POTS 22 is on-hook in step 57 or an on-hook signal is transmitted from the PSTN (58), the control returns to step 52 as well.

Otherwise, if the ring is received from the cellular / PCS network, it transmits a ring signal to the POTS 22 (59) and monitors whether the P0TS 22 is off-hook. When the POTS 22 is off-hooked (60), a send key DM message is created and transmitted to the mobile phone 24 (61). Otherwise, if the ring off message is sent before the P0TS 22 off-hooks, it returns to step 52 after sending a ring off signal to the POTS. Subsequent to step 61, a call state is switched to in step 62. In step 62, if the POTS 22 is on-hook or a Call Disconnection message is sent from the cellular / PCS network (63), the process returns to step 52.

While the invention has been described using one embodiment, those skilled in the art will be able to make various changes without departing from the scope of the claims.

According to the device of the present invention, since the indoor subscriber does not communicate with the subscriber of the mobile communication network via the wired public network, not only does it increase the utilization efficiency of the wired public network, but also the call sound quality is not degraded, and a double fee must be paid. Problem is solved

Claims (4)

MCU (Main Control Unit) (11), Plain 0ld Terminal Services Interface (12), Mobile interface 13, PSTN interface unit 14, PSTN or cellular / PCS switch unit 15, and A mobile phone incoming / outgoing proxy device (MCT) for a PSTN subscriber, comprising a DTMF interface unit (16). The mobile phone incoming / outgoing proxy device (MCT) for a PSTN subscriber according to claim 1, further comprising a power supply unit. Checking if the POTS is off-hook, When the off-hook inspection determines that the POTS is off-hook, switching to off-hook mode to accept a key input; Checking the input key value, and As a result of the input key value check, if the key value is a specific key value, a send key request message is created and sent to the mobile phone. Otherwise, a DM message for the key value is created. Mobile phone incoming / outgoing substitute method for a PSTN subscriber comprising the step of transmitting to a mobile phone. Checking if the POTS is off-hook, When the off-hook inspection determines that the POTS is off-hook, switching to off-hook mode to accept a key input; Performing number analysis on the input key value; Selecting a connection to a PSTN or a cellular / PCS network according to the number analysis result; When the connection to the cellular / PCS network is selected in the connection selection step, the input key value is checked, and if the key value is a specific key value, a send key request message is created and transmitted to the mobile phone. Otherwise, creating a DM message for the key value and sending it to the mobile phone. Mobile phone incoming / outgoing proxy method for a PSTN subscriber, comprising a.