KR0143049B1 - Handover Method of On-premises Wireless Telephone System - Google Patents

Abstract

The present invention relates to a method for automatic handover of a wireless telephone system in a premises, and in particular, a wireless telephone user during a call moves to a new fixed device and a wireless communication line in an adjacent area, regardless of where the system moves. It is to keep a good call continuously without interruption.

Description

Handover Method of On-premises Wireless Telephone System

1 is a block diagram of a general wireless telephone system in the premises.

2 is a block diagram of the portable apparatus shown in FIG.

3 is a configuration diagram of the fixing device shown in FIG.

4 is a configuration diagram of the control device shown in FIG.

5 is an exemplary diagram of a mobile device movement path.

6 is a structural diagram of transmission data used in an on-premises wireless telephone system.

7 is an explanatory diagram showing a handover procedure on the same channel.

8 is an explanatory diagram showing a handover procedure on different channels.

* Explanation of symbols for main parts of the drawings

1 _{1 to} 1 _n : portable device 20: antenna

2 ₁ to 2 _n : fixing device 21: combiner

3: controller 22: transmitter / receiver

4: private exchange 23: wireless device controller

5: public telephone network 24: fixed device controller

10: transmitter / receiver 25: line connector

11: TDD controller 26: power supply

13: A / D converter 14: Microcontroller

31: system management unit 15: liquid crystal display

32: Main control unit 16: Dial pad

33: fixing device connection part 17: memory part

34: Memory unit 18: Speaker

35: exchanger connection part 19: microphone

The present invention relates to a method for automatic handover of a wireless telephone system in a premises, and in particular, a wireless telephone user during a call moves to a new fixed device and a wireless communication line in an adjacent area, regardless of where the system moves. The present invention relates to a handover method of an on-premises wireless telephone system which is suitable for maintaining a good quality call continuously without interruption of a call.

In general, the wireless telephone system in the premises can be largely divided into public use and private use. In the case of the public use, the wireless telephone user can only make a call and cannot receive the call.

In addition, private use can be used in various forms. As a first example, it can be used as a home telephone. In this case, a handover function is not provided, and as a second example, it can be used as an on-premises wireless telephone system. Within this range, handover can be implemented in different ways for each system.

FIG. 1 shows a general private premises wireless telephone system configuration, which is composed of a control device 3 connected to a plurality of portable devices 1 _{1 to} 1 _n and a plurality of fixed devices 2 ₁ to 2 _n . The control device 3 is connected to the public telephone network 5 via a private switch 4.

That is, the plurality of portable devices 1 _{1 to} 1 _n are connected to the plurality of fixed devices 2 ₁ to 2 _n through a wireless link, and the fixed devices 2 ₁ to 2 _n are wired call circuits and data networks. Is connected to the control device 3 via the control device 3, which is connected to the private exchange 4, and the fixing devices 2 ₁ to 2 _n are generally referred to as base station devices and can accommodate several channels. It can have multiple channels.

In addition, the specific configuration of the portable devices (1 _{1 to} 1 _n ) used in the present invention, as shown in FIG. 2, the transmitter / receiver 10 responsible for the transmission and reception of wireless data, dual transmission and reception of data A TDD controller 11 applied to a time division duplex (TDD) scheme, an ADPCM / CODEC filter 12 for converting a voice signal into a digital signal or an analog signal, and controls the operation of the entire portable device and performs a protocol. A microcontroller 13, an A / D converter 13 for converting the received electric field strength into a digital value, a memory unit 17 for recording main information, a liquid crystal display 15, and a dial keypad 16.

And the configuration of the fixing device (2 ₁ ~ 2 _n ) is, as shown in Figure 3, the conbiner 21, the portable device and the portable device to transmit and receive the signals of several transmitters and receivers with one antenna It is connected to a similar transmitter / receiver 22, the transmitter / receiver 22, performs a TDD function, a wireless device controller 23 including an ADPCM device and a memory, a plurality of wireless device controllers, and provides a synchronization signal. It is composed of a fixed device controller 24 for managing a channel, a line connector 25 and a power supply device 26 connected to the control device 3 to transmit and receive voice and signaling signals.

Also, the configuration of the control device 3 shown in FIG. 1 is shown in detail in FIG. In other words, it is connected to the fixing device 2 to transmit and receive voice and signaling signals, and to perform the functions of the fixing device connecting part 33 and the control device 3, which transmit and receive the exchange connection part 35 and the audio signal. The main control unit 32, the system management unit 31 for the maintenance, repair, installation of the system and the switch unit 35 is connected to the memory unit 34 and the private exchange (4).

5 is an exemplary diagram of a movement path of a portable device.

In the conventional hand-over method of the conventional wireless telephone system, the portable device 1 ₁ makes a call with the fixed device 2 ₁ in the first region R1 as shown in the example of the movement path of the portable device of FIG. 5. a mobile device, as in being state a, B, the case is moved into the path of C point retainer ₍₂₁₎ with, depending on the gradually increasing distance away mobile device ₍₁₁₎ receives on the side of the electric field intensity is gradually reduced ₍₁₁₎ Gradually reaches the point B, the reception electric field strength of the fixing device 2 ₁ decreases at the same time. In this case, the portable device 1 ₁ and the fixing device 2 ₁ determine whether the handover is executed by measuring the received signal. If the portable device 1 ₁ is out of the first region R1 as shown in FIG. 5, the call is disconnected from the fixing device 2 ₁ and the wireless connection state is not established.

Conventional wireless telephone system as described above is a phenomenon that the call is disconnected when the mobile device in the call is out of the range that can communicate with the fixed device, and if there is another fixed device in the vicinity of the mobile device is located adjacent There is a problem that the reliability of the wireless telephone system in the premises deteriorates due to the lack of a handover function that allows the fixed device and the portable device to continue the call.

In order to solve the above problems, a user of a digital premises wireless telephone system initiates a call in an arbitrary area where the system is installed, and enables a call transfer with an adjacent fixed device in which a mobile device is located, even if the user moves anywhere in the premises. It provides a handover method of wireless telephone system in the premises, which can improve the reliability by maintaining continuous high quality calls without disconnection of calls and flexibly performing handover to the same channel or another channel. It is an object of the present invention.

The present invention relates to a control method of a wireless telephone system in a premises including a plurality of portable devices, a fixed device, and a control device. Step AA, BB) and the control device receiving the handover initiation signal are examined to notify a specific stationary device of the handover permission signal through the same channel, and requesting the electric field strength and handover in the corresponding channel. The process of instructing to receive a signal (step FF) and the fixed device receiving the handover permission signal transmit the signal to the portable device, and the portable device receiving the signal determines whether a handover request on the same channel is possible. After transmitting the handover request signal several times repeatedly using MUX2 and switching back to MUX1 to maintain the call for several seconds (step EE), A plurality of fixed devices in one vicinity measure the handover request signal and the electric field strength of the portable device in the corresponding channel according to the electric field strength measurement instruction signal from the control device, and transmit the electric field strength to the control device if it matches the handover request signal. Process (step EE), and the control device receiving the handover request signal from the adjacent fixed device, transmitting the handover execution signal of the portable device through the specific fixed device (step HH point), and the handover execution signal. The portable device receiving the signal notifies the control device of the response signal to the control device through the specific fixing device (step JJ), and the specific fixing device receiving the response signal stops transmitting on the corresponding channel. (Step LL), the control device receiving the response signal (step KK) transmits a handover confirmation signal to an adjacent fixed device, and sends the confirmation signal. The Shinhan adjacent fixing device transmits a handover confirmation signal to the portable device using MUX2 according to its own synchronization signal (step II), and the portable device transmitting the response signal includes the reception and adjacent fixing device of MUX2. Immediately after receiving the handover confirmation signal from the transmitter, the response signal is transmitted to the adjacent fixed device by using MUX2, and the adjacent fixed device and the portable device respectively switch to MUX1 to continue the call state (steps NN, MM), and The control device receiving the response signal instructs the specific fixed device to terminate the link, and the specific fixed device which has received the link termination signal is switched to the channel scan mode (step OO).

Hereinafter, described in detail by the accompanying drawings as follows.

The structure of the premises wireless telephone system according to the present invention is the same as the conventional one, but the structure of the transmission data is different as shown in FIG.

In the present invention, MUX1 is a data structure used during a call, and MUX2 and MUX3 are data structures used for transmitting signaling data. That is, 64B of MUX1 is 64 bits of voice data, and D is a portion carrying signaling data. The MUX2 carries signaling data on two 16Ds and is used to transfer data between the handheld and the high and low devices. In addition, MUX3 is a data structure used by a mobile device to set up a call to a fixed device. It has four identical sub-MUX structures, each of which has 8 1ODs.

7 is a process diagram showing a handover procedure in the same channel, and FIG. 8 is a process diagram showing a handover procedure in different channels.

Referring to the present invention made as described above with reference to FIGS. 5 to 8, two handover methods are first presented.

As a first method, a handover method on the same channel that was in a call as shown in FIG. 7 will be described.

That is, the portable device 1 ₁ and the fixed device 2 ₁ measure the electric field strength and the bit error rate of the received signal, respectively, during the normal call in the first region R1, and the bit error rate is measured at regular intervals. (A and BB points), where the fixing device 2 ₁ may first instruct the handover to the portable device 1 ₁ (handover indication signal), and the portable device 1 ₁ makes the hand itself. The over start signal may be transmitted to the fixing device 2 ₁ .

On the other hand, the premises wireless telephone system uses the data structure as shown in FIG. 6, and during the call, the MUX1 is used to transmit and receive the voice signal and the signaling signal, and the handover initiation signal is the D channel carrying the signaling data of the MUX1 during the call. It is transmitted to the fixing device 2 ₁ through a link identification code and a portable device identification code, and the fixing device 2 ₁ receiving the handover start signal is immediately transmitted to the control device 3.

Therefore retainer receiving the handover start signal is controlled from the (2 ₁₎ (3) is a fixed device _{(22) (23)} is fixed and a mobile unit _(11), the device close to the fixing device ₍₂₁₎ ( ₂₁₎ notifies if not used to check and use a traffic channel in use between an immediate handover permission signal (co-channel) to the retainer ₍₂₁₎ and, adjacent to the retainer ₍₂₁₎ holding device (2 ₂ ) (2 ₃ ) to receive the electric field strength on the corresponding channel and the handover request signal transmitted from the portable device 1 ₂ (FF point).

Meanwhile, after determining the hand receiving the over-allowed signal holding device ₍₂₁₎ transmits the signal to the portable device, wherein the handover request at the above-allowing the portable device ₍₁₁₎ receiving the signal in the same channel is possible By using MUX2, handover request signal including sync data, portable device identification code and link identification code is transmitted two or three times, and then switch back to MUX1 to maintain a call for several seconds (EE point). If it does not receive the handover execution signal within a certain period of time for a certain time, it uses the second method described later.

On the other hand, the stationary devices 2 ₂ and 2 ₃ , which are scanning channels at the CC and DD points, request a handover from the portable device 3 in the corresponding channel by the electric field strength measurement indication signal from the control device 3. It begins to receive the signal, and also measures the electric field intensity of that channel, and the notified code from the portable device ₍₁₁₎ links the identification code and the portable device identification code to control unit 3 in a handover request signal received from If matched, the control device 3 immediately informs the control device 3 of the handover request signal including the received signal field strength (GG point).

In addition, the control device 3 receiving the handover request signal from the fixing device 2 ₂ or 2 ₃ executes the handover to execute the handover to the portable device 1 ₁ through the fixing device 2 ₁ . The portable device 1 ₁ which has transmitted the signal (HH point) and received the handover execution signal notifies the control device 3 via the fixing device 2 ₁ of the response signal to the signal (JJ point). .

Therefore, the fixing device 2 ₁ receiving the response signal enters the standby state after stopping transmission on the corresponding channel (LL point), and the control device 3 receiving the response signal (KK point) immediately fixes the device. The handover acknowledgment signal is transmitted to (2 ₂ ), and the fixed device (2 ₂ ) receiving the acknowledgment signal transmits the handover acknowledgment signal to the portable device (1 ₁ ) using MUX2 according to its own synchronization signal. (II points)

On the other hand, the portable device (1 ₁ ), which has transmitted the response signal at the JJ point, immediately starts receiving the MUX2, and receives the handover confirmation signal from the high / low device (2 ₂ ) immediately. 2 ₂ ) and then the fixed device 2 ₂ and the portable device 1 ₁ switch to MUX1 (NN and MM points), respectively, to continue the call.

After that, the control device 3 receiving the response to the handover confirmation signal instructs the fixing device 2 ₁ to terminate the link (OO point), and the fixing device 2 ₁ receiving the above link termination signal. Switches to channel scan mode.

The method is because the hand-over proceeds on the same channel to minimize the interruption of the audio data, and perform a rapid handover without the call severance of the switching to another channel, the mobile device ₍₁₁₎ is a retainer ( 2 ₁ ) and the double time division synchronization maintained during the call should be set to the dual time division synchronization of the fixed device (2 ₂ ) between JJ point and MM point. Since the channels are already known to each other, the link reset process and the exchange of MUX change signals are necessary. Handover can be executed quickly without

Next, as a second method, a method of performing handover on different channels is illustrated in FIG. 8, which will be described in detail. The portable device 1 ₁ and the fixing device 2 ₁ at AA, BB, CC, and DD points will be described. ) Operation is the same as in the first method and FIG. 7, and the control device 3 having received the handover start signal at the FF point is currently carried by the stationary device 2 ₂ (2 ₃ ) adjacent to the height device 2 ₁ . Check that the device 1 ₁ and the stationary device 2 ₁ are using the same channel as the channel used during the call.

If the stationary device 2 ₂ (2 ₃ ) is using that channel, the handover permission signal (following channel) informing the mobile device 1 ₁ to request a handover using any other free channel. a transfer to the portable device ₍₁₁₎ via a retainer _(21), and wherein the portable device ₍₁₁₎ is to find any free channel interrupt the call in who call channel temporarily and through a channel scanning in MUX3 format Accordingly, a handover request signal including a link identification code and a portable device identification code is emitted in a broadcast form (PP point), and the MUX3 transmission minimizes call interruption between the mobile device 1 ₁ and the fixed device 2 ₁ . In order to transmit the data of MUX3 format several times, it immediately returns to the channel that was in a call and keeps the call state again for several seconds with the fixed device (2 ₁ ), and the above process was performed several times. Han Does not receive the confirmation signal over the mobile unit ₍₁₁₎ continues to persist on the phone with the retainer _(21).

On the other hand, any fixed device (2 ₂ ) (2 ₃ ) that receives the handover request signal from the portable device (1 ₁ ) during channel scanning specifies the received signal electric field strength and the link identification code, portable device identification code and channel number. The control device 3 notifies the control device 3 of the handover request signal including the electric field strength value, and receives the request signal. Determine and transmit the handover confirmation signal to the portable device through the fixing device 2 ₂ (QQ and RR points), wherein the fixing device 2 ₂ transmits the handover confirmation signal using MUX2, where the MUX2 is portable. the device ₍₁₁₎ is to be transmitted to the reception time zone in MUX3 structure to be transmitted.

Therefore, when the handover request signal is transmitted to the MUX3, when the handover confirmation signal is received within the time of the MUX3 receiving area, the portable device 1 ₁ immediately stops transmitting the MUX3 and adjusts the MUX2 to the unique sink of the fixed device 2 ₂ . The response signal is transmitted to the fixed device 2 ₂ (RR point), and then the portable device 1 ₁ and the fixed device 2 ₂ are switched to MUX1 to maintain the call state (UU and TT point).

The subsequent process is the same as the case described above with reference to FIG. 7. Thus, the end-over process on different channels effectively utilizes the MUX3 structure to simultaneously receive the handover acknowledgment signal of the fixed device 2 ₂ . It is easy to synchronize with a dual time-division sync clock, minimizing disconnection and enabling handovers quickly.

As described above, the handover method of the on-premises wireless telephone system according to the present invention maintains a high quality call without interruption of the call even if the user moves anywhere in the premise by starting a call in any area where the system is installed. By taking advantage of the communication, it can transmit and receive the necessary signals while continuing the call, minimizing the disconnection of the call, and performing the handover to the same channel or another channel flexibly, so the channel scanning must be performed for the same channel. By providing a unique effect that is unnecessary, it can contribute to improving the reliability of the wireless telephone system in the premises.

Claims (6)

A control method of a wireless telephone system in a premises comprising a plurality of portable devices, a fixed device and a control device. (B) a process of transmitting and receiving a handover instruction and a start signal between a portable apparatus, a fixed apparatus, and a control apparatus in a specific region; The control device receiving the handover initiation signal checks a busy channel, notifies the handover permission signal to a specific fixed device through the same channel, and instructs to receive the electric field strength and the handover request signal from the corresponding channel. (Step FF), and c. The fixed device receiving the handover permission signal transmits the signal to a portable device, and the portable device receiving the handover signal transmits the handover request signal several times using MUX2 after determining whether a handover request is possible on the same channel. And to switch back to MUX1 to hold the call for several seconds (step EE); The adjacent multiple fixed devices measure the handover request signal number and the electric field strength of the portable device in the corresponding channel according to the electric field strength measurement command signal from the control device, and transmit the signal to the control device if the handover request signal is matched. E) the process (step EE); Receiving a handover request signal from an adjacent fixed device, transmitting a handover execution signal of the portable device through the specific fixed device (step HH); The portable device receiving the handover execution signal notifying the control device of the response signal to the signal through a specific fixing device (step JJ); The specific fixing device receiving the response signal enters a standby state in which transmission is stopped on the corresponding channel (step LL), and the control device receiving the response signal (step KK) transmits a handover confirmation signal to an adjacent fixed device. The adjacent fixed device receiving the confirmation signal transmits a handover confirmation signal to the portable device using MUX2 according to its own synchronization signal (step II). The portable device that transmits the response signal immediately transmits the response signal to the adjacent fixed device by using MUX2 after receiving the handover confirmation signal from the reception of the MUX2 and the adjacent fixed device, and then the adjacent fixed device and the portable device to MUX1, respectively. (I) the process of switching to continue the call (step NN, MM); The control device receiving the response signal instructs the specific fixed device to terminate the link, and the specific fixed device which has received the link termination signal is switched to the channel scan mode (step OO) on the same channel in a call. A handover method for an on-premises wireless telephone system, characterized in that handover is performed. A control method of a wireless telephone system in a premises comprising a plurality of portable devices, a fixed device and a control device. (B) a process of transmitting and receiving a handover instruction and a start signal between a portable apparatus, a fixed apparatus, and a control apparatus in a specific region; The control device receiving the handover initiation signal carries a handover permission signal through the specific fixing device to notify the portable device to request handover to any other free channel when any fixed device uses the corresponding channel. Transmitting to the device (step FF); The mobile device suspends the call of the channel being called, finds an empty channel through channel scanning, and fires a handover request signal in a broadcast form according to the MUX3 format (step PP); Any fixed device that has received the handover request signal measures the received signal field strength and notifies the control device of the handover request signal (step QQ); The control device receiving the request signal determines a fixed device that has reported the largest electric field strength as a target to be handed over, and transmits the signal to the portable device through an arbitrary fixed device (step RR). If the handover confirmation signal is received within the time of the MUX3 receiving area, the portable device stops transmitting MUX3 and transmits a response signal to an arbitrary fixed device to MUX2 in synchronization with a unique sync (step UU); Switching to MUX2 to keep the mobile device and any fixed device in a call state (step TT); The control device receiving the response signal instructs the specific fixed device to terminate the link, and the specific fixed device receiving the link termination signal is switched to the channel scan mode (step SS) to handover on different channels. A handover method of a premises wireless telephone system, characterized in that is carried out. The handover method of claim 1, wherein the portable device transmits a handover request signal using MUX2, and the fixed device transmits a handover request signal using MUX2. The handover of the wireless telephone system of claim 1, wherein the portable device transmits a handover request signal using MUX3 and receives a handover confirmation signal using MUX2 from a fixed device in a reception area. Way. The handover method of claim 2, wherein the portable device transmits a handover request signal using MUX2, and the fixed device transmits a handover request signal using MUX2. The handover of the wireless telephone system of claim 2, wherein the portable device transmits a handover request signal using MUX3 and receives a handover confirmation signal using MUX2 from a fixed device in a reception area. Way.