KR100255818B1 - A directly communicating method between city phones - Google Patents

Abstract

PURPOSE: A direct calling method between CPPs(Cordless Portable Parts) is provided to achieve a direct calling between a CPP and a CPP by embodying a radio mode in the CPPs. CONSTITUTION: If a calling is started, a CPP judges whether the calling is to a base station or an HBS(Home Base Station)(51). If it is judged that the calling is to a base station or an HBS, the CPP establishes a link from an MBS(Mobile Base Station) to the base station or the HBS(52). In case that the calling is to another CPP(53), the CPP judges that it is a concurrent paging(54). In case that the calling is the concurrent paging, the CPP pages all CPPs from the MBS according to the concurrent paging(55). The CPP sets up a link between the MBS and the first CPP to respond(56). However, if the calling is not the concurrent paging, the CPP opens up a link between the MBS and a specific CPP(57).

Description

Method of directly communicating between city-phones

The present invention relates to a method for making a direct call between city phones so that the city phone can be used as a radio.

In general, a public wireless telephone network using a city phone is known as "CT-2," and CT-2 can be defined as a universal mobile communication service that has developed a conventional wireless wireless telephone (CT-1) into a public wireless telephone. . CT-2 is a system for pedestrian communication service compared to existing cellular, and minimizes the mobile network and directly connects to the public telephone network. Thus, it is easy to implement a city phone and a base station, thereby minimizing the economic burden at a low usage fee. . The "CT-2 Plus (+)" terminal, which has improved the CT-2 for outgoing calls, has a built-in pager in the city phone. Indirect call function using the meet-me service, an additional service of the wireless pager. Can be used.

As shown in (a) of FIG. 1, such a city phone is a plurality of base stations 12a, 12b: BS connected to a public telephone network 16, or a city phone 10a, 10b via a home base station 14: HBS installed in a home. ) Can be connected to the public telephone network, the base station management system 17 manages jurisdiction base stations via the public telephone network 16, and the subscriber management system 18 is connected to the base station management system 17 to manage all subscribers. It is configured to.

Here, the radio link between the CT-2 base station and the city phone uses a TDD scheme of 72 Kbps (144 bits, 2 ms frame), and multiplexed D channel (signal channel), B channel (voice and data channel), and SYNC channel ( Synchronization channel). These channels are divided into three types of signal frames (MUX1, MUX2, and MUX3) according to the multiplexing method. 'MUX1' is used to transmit D and B channels, and 'MUX2' and 'MUX3' are used to transmit D and sync channels. That is, a MUX3 frame is used by a terminal (city phone) to request a radio link to make a call to a base station, and a MUX2 frame is used to establish a radio link between a base station and a city phone. The exchange of information through the established radio link is the MUX1 frame.

However, such a conventional city phone has a problem in that it is impossible to make a direct call between city phones, thereby narrowing the application range of the city phone. That is, the conventional city phone has a public (PUBLIC) mode and a home (HOME) mode, in the public mode is a mode for communicating through the public base station (BS), the home mode to communicate using a home base station (HBS) Mode. Therefore, even though the city phone is a kind of wireless transceiver, there is a problem in that it is not possible to directly talk to another city phone like a radio using the city phone.

Meanwhile, the demand for daily radios is increasing due to the increase in leisure population, and many people are using city phones after the city phone commercial service. By the way, the conventional city phone can be called only through the home base station (HBS) or the base station (BS), the city phone is not a direct call. If the Citi phones can be directly talked with each other, they will be able to make calls very conveniently at a short distance, and the utilization of Citi phones will be increased.

Accordingly, the present invention has been made to solve the above problems and to add a new radio service to the city phone, the object of the present invention is to provide a method that can be directly between the city phone and the city phone by implementing the radio mode in the city phone. .

In order to achieve the above object, the present invention comprises the steps of setting the operation mode setting key to the public (PUBLIC), home (HOME), walkie-talkie mode; Establishing a link from the city phone (CPP) to the city phone (MBS) when the incoming call is received from the city phone (CPP) in the radio mode; Establishing a link from the home base station (HBS) to the city phone (MBS) when the call is received from the home base station (HBS) in the radio mode; When a call is made to the base station or the home base station (HBS) in the radio mode, establishing a link from the city phone (MBS) to the home base station (HBS) or the base station; Calling all city phones (CPP) registered in the city phone (MBS) when the call is made to the city phone (CPP) in the radio mode and is simultaneously called; Establishing a link between the city phone (CPP) and the city phone (MBS) that respond first after performing the step of calling all the city phones (CPP); And initiating a link from the city phone (MBS) to the designated city phone (CPP) by calling only the designated city phone (CPP) registered to the city phone (MBS) when the call is made to the city phone (CPP) in the radio mode. It is characterized by being able to make a direct phone call between two phones.

1 is a block diagram showing the configuration of a general city phone network;

2 is a state diagram for explaining switching of an operation mode in a city phone;

Figure 3 is a flow chart showing the operation classification by mode of the city phone according to the present invention,

4 is a flowchart illustrating a process of receiving in a transceiver mode according to the present invention;

5 is a flowchart illustrating a process of transmitting in a walkie-talkie mode according to the present invention;

6 is a diagram illustrating a link establishment procedure from CPP to MBS according to the present invention;

7 is a diagram illustrating a link establishment procedure from HBS to MBS according to the present invention;

8 is a diagram illustrating a link establishment procedure from an MBS to a base station or an HBS according to the present invention;

9 is a diagram illustrating a link establishment procedure from MBS to CPP according to the present invention;

10 is a diagram illustrating a link establishment procedure from MBS to CPP according to the present invention.

* Explanation of symbols for main parts of the drawings

10a, 10b: City phone 12a, 12b: Base station (BS)

14: Home Base Station (HBS) 16: Public Telephone Network (PSTN)

17: base station management system 18: subscriber management system

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, the terms used in the present invention will be briefly described to facilitate understanding of the present invention.

A "CPP" Cordless Potable Part, which is a terminal in the CT2-CAI standard commonly referred to as a "City Phone" (i.e., a City Phone), and a "CFP" as a Cordless Fixed Part, which identifies a base station or home base station. Say. A base station (BS) is a part that is wirelessly connected to a city phone in an air mode, and a home base station (HBS) is a reduced base station that allows a city phone to be used as a wireless phone at home. "MBS" is an abbreviation of "Mobile Base Station" and is a city phone capable of a walkie-talkie mode according to the present invention. In addition, 'PID' is a CPP identification code according to the CT2-CAI standard, 'LID' is a link identification code as a link identification (Link Identification). 'LS' is the link status bit, 'CHMF' is the Channel Marker bit pattern transmitted by the CFP, and 'SYNCP' is the synchronization word transmitted by the CPP on the SYNC channel. 'UI' is an unconfirmed information element message, 'LINK_REQUEST' is a link status request message for link occupancy, 'LINK_GRANT' is a CFP confirmation message that assigns a call reference ID, and 'ID_OK' is a handshake ok code word. . Depending on the link status bits, the meaning of these messages is defined in Table 1 below.

Link status meaning LS1 LS0 0 0 LINK_REQUEST 0 One LINK_GRANT One 0 ID_OK One One ID_LOST

As shown in Table 1, when LS = 00, it indicates LINK_REQUEST. LINK_REQUEST is a request to occupy a link, and is transmitted as the first packet of MUX3 during call establishment from CPP to CFP and during link establishment, or CPP responds to a call. When attempted, it is returned as a poll response from CPP to CFP using MUX2 during CFP call setup. If LS = 01, it receives LINK_REQUEST from CPP as LINK_GRANT and then sends by CFP. If LS = 10, it is a handshake packet that is sent when a valid handshake is received as an ID_OK within a one second period. ID_OK is also used to establish a link as a poll packet from the CFP and as a poll response packet from the CFP. If LS = 11, then ID_LOST is used when no valid handshake is received within the specified time.

The present invention, in addition to the conventional city phone function, as shown in (b) of Figure 1, by allowing a direct call between the city phone, it is possible to use the city phone as a radio.

As described above, in order to use the city phone as a radio, operation of the radio mode is required in addition to the PUBLIC mode and the HOME mode.

Referring to FIG. 2, whenever a designated key (for example, the 'sys' key) is pressed, the operation mode of the city phone is from the air mode 21 to the home mode 22 and the home mode 22 to the radio mode 23. Then, it switches from the radio mode 23 to the air mode 21 again. When the city phone is operated in the air mode, the call is possible through the base station (BS), but the call is impossible. When the phone is operated in the home mode, the call is possible through the home base station (HBS) and the call is possible. In the walkie-talkie mode, a direct call between city phones is not possible.

That is, the city phone having the radio mode requires a function of registering a plurality of city phones, such as a home base station (HBS), and a function of calling a specific city phone among registered city phones. In addition, the city phone (MBS) according to the present invention has a function to call a specific city phone to answer after calling all the registered city phones, the registered city phone has a function to call the city phone (MBS) according to the present invention have. To this end, the city phone of the present invention adds the radio mode to the public mode and the home mode, and can receive all the calls from the three modes in any mode, and does not perform the authentication process like the home base station (HBS).

Meanwhile, the conventional city phone has an air slot for operating in the air mode and a slot for home for operating in the home mode. However, the number of slots for the two modes varies depending on the manufacturer. In general, it has 4 to 8 slots, according to the present invention in the city phone (MBS) is further equipped with a walkie-talkie mode in addition to the slots for the air slots and home slots in addition to the radio slots, for the registered CPP The registration information is being saved. These slots are located in the E ² PROM as in the existing city phone, the contents are not erased even if the power is lost, it can be deleted and registered by the user's operation.

As described above, the operation by the city phone equipped with the air mode, the home mode, and the transceiver mode according to the present invention will be described with reference to FIGS. 2 to 10.

In the city phone according to the present invention, other city phones are registered in the slot for the radio. Looking at the call method for each mode using such a city phone, in general, press the 'sys' key to select the mode and then press the call button to call, press the phone number or dial the phone number when calling in the public mode (21) Press the number and then press the call button. In public mode, the receive function is not currently being serviced.

In the home mode 22, the call is the same as the public mode, and when receiving, all the city phones registered in the home base station (HBS) ring and ring, and among the city phones, a call is made to the responding city phone. As such, in home mode, there is no function to ring a ring by assigning a specific city phone only.

In the radio mode 23 according to the present invention, simultaneous calls and designated calls are possible at the time of origination, and are identical to other modes at the time of reception. In the simultaneous call during the call, pressing the call button calls all the city phones registered in the radio slot and calls the first city phone that is answered. The designated call is made by pressing the city phone number to be called, and then pressing the call button to call only the designated city phone and when the corresponding city phone answers, the call is made directly between the city phones.

That is, as shown in FIG. 3, when the mode key is input, the mode switching operation is performed (31, 38). If the current mode is the air mode by the mode switching, the air mode is operated as described above (32). 35, the home mode operates in the home mode (33, 36). If the current mode is the radio mode, it operates according to the flow shown in FIGS. 4 to 10 (34, 37).

According to the present invention, the operation in the transceiver mode is divided into an incoming call and an outgoing call. The incoming call is performed according to a procedure as shown in FIG. 4.

Referring to Figure 4, if the incoming call is made by the call of the other party in step 41 it is determined whether the incoming call from the CPP. If it is determined in step 41 that the call is from CPP, a link from CPP to MBS is opened in step 42, and if it is not from CPP in step 41, it is determined whether the call is from HBS in step 43. If it is an incoming call from HBS in step 43, a link from HBS to MBS is established in step 44.

In step 42, the link establishment from CPP to MBS is performed as shown in FIG. 6. First, when a link request (LINK_REQUEST) message is sent to MBS with (CHMP, MUX3) PID, LID, LS = 00 in CPP, and secondly, MBS Regardless of current mode, compares PID and LID and sends link permission (LINK_GRANT) message with (SYNCF, MUX2) PID, LID, LS = 01 when CPP is registered in MBS. Thirdly, upon receiving the link grant message, the CPP generates an ID OK message of (SYNCP, MUX2) PID, LID, LS = 10. In this way, the link from the CPP to the MBS establishes the MBS as the CFP, and responds to the registered city phone by checking the information registered in the slot for the call request to the CPP. At this time, regardless of the mode (public, home, radio) of the MBS checks the information registered in each slot and responds to each mode.

Further, in step 44, the link establishment from the HBS to the MBS is performed. As shown in FIG. 7, when the HBS transmits an ID_OK message to the MBS with (CHMF, MUX2) PID, LID, LS = 10, the MBS detects a poll. Subsequently (CHMF, MUX2), SIG or FI messages are sent from HBS to MBS to ring a specific MBS. The ID_OK message is then transmitted to the MBS with (CHMF, MUX2) PID, LID, LS = 10. In this polling process, when the corresponding CPP attempts a call by pressing the "send" key, the MBS sends a link request (LINK_REQUEST) message to the HBS with (SYNCP, MUX2) PID, LID, and LS = 00. Accordingly, HBS transmits a link permission message (LINK_GRANT) with (SYNC, MUX2) PID, LID and LS = 01, and MBS sends HBS ID_OK message with (SYNCP, MUX2) PID, LID and LS = 10. To send.

As such, when the MBS is registered in the HBS, the MBS plays a CPP role. When you make a call from HBS, it answers the same as a normal city phone (CPP). The MBS will ring if the PID of ID_OK is valid in any mode. If the user presses the "send" key, the MBS sends a link request (LINK_REQUEST) message to perform the call.

On the other hand, Figure 5 is a flow chart illustrating a process for transmitting in the radio mode in accordance with the present invention. Referring to FIG. 5, if transmission is started, it is determined whether transmission is to the base station or the HBS in step 51. In step 51, if the call is made to the base station or the HBS, a link is established from the MBS to the HBS or the base station in step 52. If it is not the call to the base station or the HBS in step 51, it is determined whether the call is made to the CPP in step 53. If the call is made to the CPP in step 53, it is determined in step 54 whether it is a simultaneous call. If it is determined that the call is made in step 54, the call is made from the MBS to all the CPPs according to the call in step 55, and then a link is established between the first CPP and the MBS that was first responded in step 56. If not at the same time in step 54, the link is established from the MBS to the specific CPP according to the designated call in step 57. As such, when making a call to CPP, a link is established in a different procedure depending on whether a simultaneous call or a designated call is made.

In accordance with the present invention, the link establishment procedure (step 52) from the MBS to the base station or the HBS is shown in FIG. 8, and the link request from the MBS to the base station or the HBS with (CHMP, MUX3) PID, LID, LS = 00. LINK_REQUEST) message is transmitted and the base station or the HBS compares the PID and the LID regardless of the current mode, and if the CPP is registered in the MBS, it responds with the link permission and proceeds to the next step. That is, when the base station or the HBS receives the link request (LINK_REQUEST) message, it transmits the link grant message to the MBS with (SYNCF, MUX2) PID, LID, LS = 01. Accordingly, the MBS transmits (SYNCP, MUX2) PID, LID The ID_OK message is transmitted from the MBS to the base station or the HBS with LS = 10.

In addition, the procedure for establishing a link from the MBS to the CPP during the simultaneous call (steps 55 and 56) is performed when the CPP polls all the CPPs from the MBS when the CPP is out of the MBS coverage, and the CPP is the MBS. If it is within the coverage of the MBS, the process of polling all the CPP in the MBS, and the process of establishing a link with the CPP that answered the call in the MBS.

That is, if CPP1 and CPP2 are out of MBS coverage, MBS calls CPP1 with (CHMF, MUX2) PID1, LID, LS = 10, and sends ring with (CHMF, MUX2) SIG or FI to ring CPP1 This rings. MBS then calls CPP2 with (CHMF, MUX2) PID2, LID, LS = 10 and sends a ring with (CHMF, MUX2) SIG or FI to ring the CPP2. If CPP1 is within the coverage of CFP, MBS sends ID OK with (CHMF, MUX2) PID1, LID, LS = 10 and CPP1 sends ID_OK message with (CHMF, MUX2) PID, LID, LS = 10. Send to MBS.

Then, when MBS calls CPP1 with (CHMF, MUX2) PID1, LID, LS = 10, if CPP1 tries to make a call by pressing the "send" key, CPP1 will call (SYNCP, MUX2) PID, LID, LS = 00. This sends a link request (LINK_REQUEST) message to the MBS. MBS transmits a link grant message with (SYNC, MUX2) PID, LID, LS = 01, and accordingly, CPP1 transmits ID_OK message to MBS with (SYNCP, MUX2) PID, LID, LS = 10.

In case of simultaneous call like this, all CPPs registered in MBS are called in sequence, and the called CPP rings and the call is made between CPP and MBS answered by pressing "send" key first.

On the other hand, the link establishment procedure (step 57) from MBS to CPP according to the designated call (step 57), the MBS transmits the ID_OK message with (CHMF, MUX2) PID, LID, LS = 10 (CHMF, If you send a ring with MUX2), SIG or FI and send ID OK with (CHMF, MUX2) PID, LID, LS = 10, the CPP will ring after detecting the poll.

CPP sends a link request (LINK_REQUEST) message with (SYNCP, MUX2) PID, LID, LS = 00 when attempting a call by pressing "send" key when ringing. Accordingly, the MBS transmits a link permission (LINK_GRANT) with (SYNCF, MUX2) PID, LID, and LS = 01, and then the CPP transmits an ID_OK message with (SYNCP, MUX2) PID, LID, and LS = 10.

As such, when a specific CPP is designated and called among several CPPs registered in the MBS, ID_OK and SIG or FI are sent only to the designated CPP.

As described above, the present invention is very simple by adding a radio slot to the city phone, and can easily talk directly to another city phone like the radio using the city phone, so that the use of the city phone is extended and has a very convenient effect.

Claims (2)

Setting an operation mode setting key to a public (PUBLIC), a home (HOME), or a transceiver mode; Establishing a link from the city phone (CPP) to the city phone (MBS) when the incoming call is received from the city phone (CPP) in the radio mode; Establishing a link from the home base station (HBS) to the city phone (MBS) when the call is received from the home base station (HBS) in the radio mode; When a call is made to the base station or the home base station (HBS) in the radio mode, establishing a link from the city phone (MBS) to the home base station (HBS) or the base station; Calling all city phones (CPP) registered in the city phone (MBS) when the call is made to the city phone (CPP) in the radio mode and is simultaneously called; Establishing a link between the city phone (CPP) and the city phone (MBS) that respond first after performing the step of calling all the city phones (CPP); And In the radio mode, a call is made to the city phone (CPP), but if the designated call is made, only the designated city phone (CPP) registered in the city phone (MBS) is opened and a link is opened from the city phone (MBS) to the designated city phone (CPP). A direct communication method between city phones, wherein the city phones can be directly talked like a radio. 2. The method of claim 1, wherein the city phone implements a slot for a radio mode in an E ² PROM. 3.

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