KR101470443B1 - Data Terminal and Handover Method for the Same - Google Patents

Abstract

An information terminal for seamlessly receiving a DMB broadcasting signal even when an information terminal having a DMB broadcasting receiving function moves between boundaries and a handover method therefor are proposed.

An information terminal according to the present invention is an information terminal connected to a dual DMB receiving module having a GPS receiving module and a plurality of front end units, the information terminal comprising: a memory storing DMB transmitting station information installed in each region; When a handover is required for outputting a DMB broadcast signal received by the front end unit of the DMB receiving terminal, when at least one DMB transmitting station for transmitting the same signal as the currently outputted DMB broadcasting signal is searched with reference to the DMB transmitting station information, And a handover module for connecting to at least one of the DMB transmission stations searched by another front end unit excluding the front end unit for receiving the output DMB broadcasting signal, Even when the transmission frequency is changed, You can perform automatic handover with reference to specific frequency information.

DMB, handover

Description

Technical Field [0001] The present invention relates to an information terminal and a handover method for the same,

More particularly, the present invention relates to an information terminal for seamlessly receiving a DMB broadcasting signal even when an information terminal having a DMB (Digital Multimedia Broadcasting) broadcast receiving function moves between boundaries, and a handover ≪ / RTI >

DMB is a system standard used for providing multimedia broadcasting service including video based on DAB (Digital Audio Broadcasting) system, which is a European digital radio broadcasting standard that provides high quality audio service and data service at the same time.

Currently, the DMB service area is limited, so each broadcasting station is installed in each area and broadcasting signals covering the area are transmitted. In this case, in order to prevent confusion between transmitting stations, the same broadcasting signal is provided at different frequencies for different areas, and there are cases where a content is produced and provided for each region.

Accordingly, when the user watches the DMB and moves to another area or wants to watch a self-service broadcast in the area, there is a problem that the user can not watch the broadcast by the channel information preset in the DMB receiver. Accordingly, when the user moves to another area, the user must perform channel setting by scanning broadcast signals transmitted from a transmission station installed in the corresponding area.

As described above, conventionally, there is a disadvantage that the user must manually search for a broadcast signal when moving to another area, and there is a disadvantage that the user can not watch a broadcast while searching for a receivable broadcast signal.

In order to solve such a problem, recently, it has been proposed to prepare for handover by transmitting neighboring transmitting station information together when a broadcasting signal is transmitted from a DMB transmitting station to a DMB module. However, in this case, since the handover related information must be received at the designated period from the currently connected transmitting station, the size of the broadcast signal is unnecessarily increased.

SUMMARY OF THE INVENTION It is therefore an object of the present invention to provide an information terminal having a dual DMB receiving module, which is capable of watching a broadcasting signal by one of the DMB receiving modules, There is a technical problem in that it is possible to watch the DMB broadcasting signal through the information terminal without interruption.

Another object of the present invention is to provide an information terminal capable of automatically accessing a channel for transmitting a broadcast signal being received according to channel information provided by a transmission station when an information terminal equipped with a DMB receiving module moves, Over method.

According to another aspect of the present invention, there is provided a method of controlling a communication system, the method comprising: determining a transmission station to be re-connected according to a distance between an adjacent DMB transmission station and an information terminal, a signal intensity from an adjacent DMB transmission station to an information terminal, An information terminal capable of watching a DMB broadcast without interruption, and a handover method therefor.

According to an aspect of the present invention, there is provided an information terminal including a Global Positioning System (GPS) receiving module and a dual DMB (Digital Multimedia Broadcasting) receiving module having a plurality of front- A video terminal, comprising: a memory for storing DMB transmission station information installed in each region; And when a handover is required for outputting a DMB broadcast signal received by one of the plurality of front end units, the same signal as the currently outputted DMB broadcast signal is transmitted with reference to the DMB transmission station information A handover module for connecting to at least one of the searched DMB transmitting stations by another front end unit other than the front end unit for receiving the currently output DMB broadcasting signal when at least one DMB transmitting station is searched; .

Meanwhile, a handover method in an information terminal according to an embodiment of the present invention includes a GPS (Global Positioning System) receiving module and a dual DMB (Digital Multimedia Broadcasting) receiving module having a plurality of front end units, A first step of storing DMB transmission station information installed in each region; A second step of measuring a current position of the information terminal as the information terminal which receives and outputs the DMB broadcasting signal is moved by one of the plurality of front end modules; A third step of referring to a DMB transmission station installed in an area where the information terminal is located by referring to the DMB transmission station information; A fourth step of checking whether there is a DMB transmission station for transmitting the same broadcasting signal as the DMB broadcasting signal currently output by the information terminal, among the DMB transmission stations checked in the third step; And a fifth step of, if there is a DMB transmitting station for transmitting the same broadcasting signal as a result of the checking in the fourth step, switching the connection by another front end unit excluding the front end unit for receiving the currently output DMB broadcasting signal .

According to the present invention, even when the information terminal having the dual DMB receiving module shifts the boundary between the regions and the transmission frequency of the broadcasting signal is changed, the handover can be automatically performed with reference to the stored frequency information of each transmitting station have.

As a result, it is possible to continuously view the broadcast signal that was being watched, thereby improving the quality of the DMB broadcast service.

On the other hand, even when there is no transmission station for transmitting a broadcasting signal that is being watched in the area after the information terminal has moved, the distance between the information terminal and the adjacent DMB transmission station, the intensity of the signal received from the adjacent DMB transmission station to the information terminal, The transmitting station to be handed-over can be manually or automatically selected based on the result of weighting the distance to the received signal strength, so that the user can always watch the DMB broadcasting through the information terminal.

Hereinafter, preferred embodiments of the present invention will be described more specifically with reference to the accompanying drawings.

1 is a diagram for explaining a concept of a handover according to the present invention.

1, the information terminal 10 is connected to a DMB transmitting station # 1 (20) for transmitting signals from a broadcasting station A, a broadcasting station B and a broadcasting station C in a region A, and a broadcasting station A Receives the broadcast signal, and outputs the broadcast signal. However, when the information terminal 10 moves from the area A to the area B, the broadcasting signal transmitted from the transmission station # 1 20 becomes weak and the distance from the transmission station # 1 20 continuously increases, .

In order to prevent such a phenomenon, the information terminal 10 according to the present invention has a dual DMB receiving module, and stores transmission area information tables for each region, and watches broadcasting signals through any one of the DMB receiving modules, When a handover is required, the connection is switched through another DMB receiving module with reference to the transmission site information table.

That is, as the information terminal 10 moves toward the area B, it inquires of the transmitting station information table and displays the transmitting station list (transmitting station # 2 22, transmitting station # 3 24) installed in the area B after the information terminal 10 moves, ). If there is a transmitting station for transmitting the same broadcasting signal as the broadcasting signal which is being watched among the broadcasting signals transmitted from the searched transmitting stations 22 and 24, the distance or signal intensity from each transmitting station 22, 24 to the information terminal is And performs handover based on the received signal.

For example, the transmitting station # 2 22 installed in the area B transmits signals from the broadcasting station A, the broadcasting station B and the broadcasting station C, and the transmitting station # 3 24 transmits signals from the broadcasting station A, . In this case, the information terminal 10, which has moved from the area A to the area B, receives the distance from the information terminal 10, or the distance from the information terminal 10 to the information terminal 10, Handover is performed on the basis of a result obtained by assigning a distance to a received signal strength or a weight.

Here, it is preferable that the received signal strength from each transmitting station 22, 24 to the information terminal 10 is measured for at least one broadcast channel served at each transmitting station. However, the method of measuring the signal strength is not limited thereto. For example, the measurement may be performed for a channel commonly used at each transmission station (for example, TPEG (Transport Protocol Expert Group) channel) It is also possible to calculate and use the average value.

On the other hand, only the transmitting station # 4 (26) and the transmitting station # 5 (28) for transmitting the signals from the broadcasting station B and the broadcasting station C exist in the area C, but there is no transmitting station for transmitting the signal from the broadcasting station A. Accordingly, when the information terminal 10 moves from the area A to the area C, the information terminal 10 can confirm that there is no transmission station for transmitting the broadcast signal that was being watched through the transmission site information table.

Accordingly, when the information terminal 10 moves to the area C, a list of accessible transmission stations is extracted as candidates for selecting one of the broadcast signals from the broadcasting station B or the broadcasting station C, and presented to the user, And selects a broadcasting station and a broadcasting channel to which the information terminal 10 itself will switch the connection, and performs handover.

At this time, the candidate transmission station list can be determined based on the distance between the information terminal 10 and the transmitting station and / or the received signal strength from the transmitting station to the information terminal 10.

In the present invention, when handover is performed to the same channel or another channel in consideration of a reception signal from the transmitting station to the information terminal 10, the signal strength from each transmitting station is measured a plurality of times and an average value is applied, Or the average value of the signal strength) of the handover target candidate list by weighting the distance from the information terminal 10 to the handover target candidate list. In this case, due to an error in temporarily handing over a signal to a transmitting station from which a good signal is transmitted, or an error of handing over to a transmitting station which is close to the information terminal but whose service quality is poor due to an obstacle (building, mountain, etc.) It is possible to prevent occurrence of a situation in which an over is required.

To this end, the information terminal 10 of the present invention is equipped with a GPS receiving module. The information terminal 10 also stores transmission position information (latitude / longitude coordinates (GPS coordinates)) for each broadcast signal, transmission channel information of each transmission station, frequency information allocated to each transmission station, and the like.

As described above, according to the present invention, when an information terminal receiving a DMB broadcasting signal moves through an interregional boundary, a handover is performed in consideration of the distance (or signal strength) to the information terminal, thereby enabling the DMB broadcasting to be seamlessly watched.

2 is a configuration diagram of an information terminal according to the present invention.

The information terminal 10 according to the present invention includes a control unit 110, a memory 120 and a handover module 160. The GPS receiving module 140 and the dual DMB receiving module 150 It can be built-in or external. In addition, the information terminal 10 may further provide a service other than the DMB broadcast receiving function. The application service module 130 may further include an application service module 130, and the application service module 130 may be, for example, a navigation module.

More specifically, the control unit 110 controls the overall operation of the information terminal 10, and the memory 120 stores transmission station location information (latitude / longitude coordinates) for each broadcasting signal, channel information of each transmission station, And so on. If the information terminal 10 is a navigation terminal, it is needless to say that the memory 120 further stores information necessary for route calculation and guidance, such as road information, map information, and major terrain information.

The GPS receiving module 140 receives satellite orbit information and pseudo range (PR) information from a GPS satellite (not shown) to calculate the current position of the information terminal 10. [

In addition, the dual DMB receiving module 150 tunes to the DMB transmitting station through one of the DMB receiving modules when receiving power of the controller 110, and receives the broadcasting signal. If a handover is required, the DMB receiving module is connected to the handover target transmission station through another DMB receiving module, and the connection state and the driving state of the DMB receiving module are switched.

Meanwhile, the handover module 160 calculates the position of the information terminal 10 when it is required to perform a handover, determines the handover target transmission station by referring to the transmitting station information of each broadcasting signal stored in the memory 120 do. That is, when the information terminal 10 moves across the boundary between the regions, it is determined whether there is at least one transmitting station for transmitting a broadcasting signal that is being watched among the transmitting stations installed in the area after the moving. The priorities are determined according to the distance from the transmitting station to which the broadcasting signal is being watched and the distance to the information terminal, the intensity of the signal received by the information terminal, or the distance to the received signal strength is weighted. And performs handover to a transmission station having

If there is no transmission station for transmitting the broadcasting signal currently being watched in the area after the movement, a candidate list is generated on the basis of the distance information between the information terminal and the transmission station installed in the area, And then performs handover by selecting any of the channels served by the selected transmitting station. At this time, it is also possible to provide a candidate list to the user, select a transmission station to which the user desires to connect, and perform a handover by selecting any one of broadcast channels served at the selected transmission station.

In another embodiment of the present invention, the handover module 160 may generate a handover candidate list according to the strength of a signal received from a plurality of adjacent transmitting stations to the information terminal 10. Here, the received signal strength may be measured for at least one of a plurality of broadcast channels served from each transmitting station, for a channel commonly used at each transmitting station (for example, a TPEG channel) It is also possible to calculate the average value of each broadcast channel of the transmitting station after the measurement.

In addition, in another embodiment of the present invention, the handover module 160 assigns the distance between each transmitting station and the information terminal 10 as a weight to the received signal strength from the adjacent transmitting station to the information terminal 10, You can also create a list.

In order to more accurately generate the handover target candidate list when the candidate list is generated in consideration of the received signal strength, the average value can be calculated by measuring the signal strength from the adjacent transmitting station a plurality of times. In this case, It is possible to prevent handover to a good transmitting station. Then, by giving the distance from the information terminal 10 to the signal strength average value from the adjacent transmitting station as a weight, the handover object can be detected more accurately.

3 is a detailed configuration diagram of the dual DMB receiving module shown in FIG.

The dual DMB receiving module 150 includes a front end unit 1510 and a DMB signal processing unit 1520. The front end unit 1510 includes a first front end unit 1512 and a second front end unit 1512. [ End unit 1514 as shown in FIG.

As power is applied to the information terminal, the first and second front end units 1512 and 1514 are driven. When one of the front-end units searches for a signal received from an adjacent DMB transmitting station through an antenna and the user selects a specific channel, the signal is received, amplified, converted into a baseband signal, . To this end, the first and second front-end units 1512 and 1514 may include a high-frequency processing unit and a baseband processing unit, respectively.

The DMB signal processing unit 1520 receives a broadcast signal converted into baseband digital data from the front-end unit 1510, demodulates and decodes the broadcast signal, extracts a video signal and a voice signal, A processing unit 1524 and a data processing unit 1526.

In this manner, while one of the front-end units receives the broadcast signal, the handover module 160 measures the strength of the broadcast signal being received by the corresponding front-end unit, and determines whether handover is necessary. The remaining front-end units receive broadcast signals from the transmitting stations adjacent to the information terminal 10, respectively, and transmit them to the handover module 160. The handover module 160 determines the handover target transmitting station, Create a list.

As described above, when the dual DMB receiving module 150 is powered on, the two front-end units 1512 and 1514 are driven to receive a broadcast signal for a channel selected by the user through one of the front-end units And the other front end unit can search for a broadcasting signal from a transmitting station to switch connection in preparation for handover of the information terminal 10. [ In addition, the other front-end unit performs channel search in preparation for handover, as well as a function of receiving traffic information and travel information by TPEG protocol, a function of checking the reception state of a broadcast signal currently being received Lt; / RTI >

If the information terminal 10 has a plurality of front-end units, any of the front-end units other than the front-end unit that receives the broadcast signal being viewed may be randomly selected to prepare for handover to be.

That is, a front end unit of the remaining front end units, which are not used for reception of a broadcast signal to be viewed, receives and outputs a broadcast signal of the corresponding channel by a front end unit by the user's channel reception command, The handover module 160 measures the signal strength from each of the adjacent transmission stations so that the information terminal can continuously receive the DMB broadcasting even after moving the boundary between the areas.

4 is a detailed configuration diagram of the handover module shown in FIG.

The handover module 160 includes a handover determination unit 1610, a position calculation unit 1620, a transmission station search unit 1630 and a connection switching unit 1640. The distance measurement unit 1650, A signal strength measuring unit 1660, and a candidate extracting unit 1670. [

Each component will be described in detail as follows.

First, the handover determination unit 1610 determines whether the intensity of the broadcast signal received through any one of the front end units (for example, the first front end unit) of the DMB receiving module 150 is less than a predetermined threshold value (E.g., 2 minutes) while the intensity of the broadcast signal is lower than a preset threshold value, it is determined that the handover is necessary and the handover module 160 is driven.

The location calculation unit 1620 receives the satellite orbit information and the PR information from the GPS satellite and measures the current position of the information terminal 10. The transmission site search unit 1630 searches the transmission site information table And inquires of the transmitting station installed in the area where the information terminal 10 is currently located, with reference to the receiving unit 1210.

5 is a diagram illustrating an example of a transmission site information table applied to the present invention.

As shown, the memory 120 includes a transmitter identifier for identifying each transmitter installed in each region, latitude / longitude coordinates as location information, broadcast channel information served by each transmitter, frequency information allocated to each channel, and the like And a transmission site information table 1210 is constructed.

The table 1210 may be updated through a predetermined field of the DMB broadcast signal when the transmission station information is added, changed or deleted, so that the information terminal 10 can always maintain the transmission station information in a new state.

In the present invention, the transmission site information table 1210 is previously stored in the information terminal 10, and when the handover is necessary, the transmission site search unit 1630 of the handover module 160 refers to the coordinate value of the transmission site information table 1210 It is possible to confirm which broadcasting station is installed in the area where the information terminal 10 is currently located.

The connection switching unit 1640 refers to the inquiry result of the transmission station searching unit 1630 and when a unique transmission station for transmitting the same signal as the broadcasting signal currently being viewed by the information terminal 10 exists, Select as destination destination. On the other hand, when there are a plurality of transmission stations for transmitting the same signal as the broadcast signal currently being viewed, the connection switching unit 1640 selects a transmission destination station according to a preset priority. Here, the priority may be determined according to the distance from the transmitting station to the information terminal, the strength of the signal received by the information terminal, or the result of weighting the distance to the received signal strength. The connection switching unit 1640 is a front-end unit (for example, a second front-end unit) other than the first front-end unit that receives the broadcast signal being viewed by the user, (Channel information for transmitting a broadcast signal currently being watched) and accesses the corresponding transmission station to receive the broadcast signal that was being watched.

Thus, even when the connection between the first front-end unit and the transmitting station is disconnected, the user can receive the broadcasting signal that was being watched from the new transmitting station through the second front-end unit, so that the user can watch the DMB broadcasting without interruption.

On the other hand, when the handover is completed and the broadcast is viewed by the second front-end unit, the first front-end module receives a signal from each adjacent transmission station and transmits the signal to the handover module 160, Be prepared.

The distance measuring unit 1650 refers to the position information of the information terminal 10 measured by the position calculating unit 1620 and the transmitting station information table 1210 to determine the distance from each transmitting station installed in the area where the information terminal 10 is located The distance to the information terminal 10 is calculated.

The signal strength measuring unit 1660 measures the intensity of a broadcast signal received from each transmitting station installed in the area where the information terminal 10 is located to the information terminal 10 once or plural times and calculates an average value thereof. Here, the received signal strength may be measured for at least one broadcast channel transmitted from each transmission station, for a channel commonly used at each transmission station, for all broadcast channels transmitted from each transmission station, And the like.

The candidate extractor 1670 generates a candidate transmission list to which the information terminal 10 switches the connection by referring to the calculation result of the distance measuring unit 1650 and / or the calculation result of the signal strength measuring unit 1660 . For example, the candidate extractor 1670 may generate a candidate list in the order of the distances between the information terminal and the transmitting station, calculated by the distance measuring unit 1650, or may generate the candidate list in the order of the received signal strength measured by the signal strength measuring unit 166 Or the average value of the broadcast signals), or generate the candidate list by weighting the distance information to the intensity (or the average value) of the broadcast signal received from the transmitting station to the information terminal 10 by weight.

In the present invention, the handover accuracy can be further improved when the signal strength from the transmitting station is measured a plurality of times and the transmitting station to be handed-over is determined based on the average value. If the distance from the information terminal 10 to the intensity of the signal from each transmitting station or the average value of the signal intensity from each transmitting station is applied as a weight, handover is performed to the transmitting station temporarily having a good signal intensity or simply to a transmitting station adjacent only to the distance without considering the influence of the obstacle Errors can be prevented.

On the other hand, in order to perform handover to one of the candidate lists generated by the candidate extracting unit 1670, the connection switching unit 1640 presents the candidate list generated by the candidate extracting unit 1670 to the user, And provides the front end unit with frequency information for connection to the transmission station and the channel selected by the user. In another embodiment of the present invention, the connection switching section 1640 itself selects any one of the candidate lists generated by the candidate extracting section 1670 (the transmitting station having the highest priority), and the connection switching section 1640 selects It is also possible to control the front-end unit to switch the connection to the channel of the transmitting station by selecting one of the transmitting stations by itself or by selecting the channel by the user. Here, the priority order of the candidate list may be a priority order of the information terminal 10, an order in which the received signal strength (or an average value thereof) to the information terminal 10 is superior or a signal strength to the information terminal 10 ), And can be in the order of being adjacent to the information terminal (10).

In another embodiment of the present invention, the handover module 160 may be configured by omitting the handover determination unit 1610. [ That is, during the operation of the dual DMB receiving apparatus 150, the handover module 160 is always operated to periodically generate a candidate list according to the position of the information terminal 10, and when a handover is required, 1640, it is possible to eliminate instantaneous interruption due to connection switching.

Next, the handover method of the information terminal described above will be described with reference to Figs. 6 to 9. Fig.

6 is a flowchart illustrating a handover method according to an embodiment of the present invention. For convenience of explanation, a front-end unit that receives a broadcast signal being viewed is referred to as a first front-end unit, and a front-end unit that searches for a transmission station for handover is described as an example of a second front-end unit.

The handover determination unit 1610 continuously monitors the strength of a broadcast signal received from the DMB receiving module 150 and determines whether handover is required or not, If the intensity of the broadcast signal received by the first front-end unit 1512 of the module 150 is less than or equal to a preset threshold, or if the intensity of the broadcast signal is less than or equal to a predetermined threshold value, , It is determined that the handover is necessary and the handover module 160 is driven (S101).

The position calculating unit 1620 measures the current position of the information terminal 10 in step S103 and the transmitting station searching unit 1630 refers to the transmitting station information table 1210 in the memory 120, And inquires of the transmitting station installed in the area where the information terminal 10 is located through the front-end unit 1514 (S105).

Then, the connection switching unit 1640 determines whether there is a unique transmission for transmitting the same broadcasting signal as the broadcasting signal received by the information terminal 10 among the transmission stations examined in step S105 (S107).

If it is determined that there is a unique transmission station for transmitting the same broadcast signal, the connection switching unit 1640 transmits transmission station information including channel information for switching the connection to the second front-end unit 1514 (S109) And the connection to the information terminal 10 is switched (S111).

On the other hand, if it is determined in step S107 that there is no unique transmission station for transmitting the same broadcast signal, it is checked whether there are a plurality of transmission stations for transmitting the same broadcast signal (S111).

As a result of checking in step S111, if there are a plurality of transmitting stations for transmitting the same broadcasting signal, the candidate extracting unit 1670 of the handover module 160 extracts, from the transmitting stations that service the corresponding broadcasting signal at the current position, , And / or a received signal strength (S115). In addition, the connection switching unit 1640 selects a transmission station having the highest priority among the extracted candidates (S117), and proceeds to step S109.

On the other hand, if it is determined in step S111 that there is no plurality of transmitting stations for transmitting the same broadcast signal, the process of FIG. 7 is performed.

7 is a flowchart illustrating a handover method according to another embodiment of the present invention.

The candidate extracting unit 1670 of the handover module 160 extracts the candidate signal from the information terminal 10 when the information terminal 10 does not exist in the area after the movement of the information terminal 10, (S201, S203), and generates a candidate list based on the distance and / or the received signal strength from each transmitting station to the information terminal 10 installed in the area where the mobile terminal 10 is located.

If the user selects one of the candidate stations, the user selects one of the broadcast channels (S205). If the user selects the transmitting station, the user selects one of the broadcast channels served by the selected transmitting station, To perform handover (S207).

On the other hand, when the user does not select a transmitting station, the connection switching unit 1640 selects one of the transmitting stations (the highest priority transmitting station) (S209), selects one of the broadcasting channels served by the transmitting station .

Here, the process (S115, S201) of the candidate extractor 1670 to generate the candidate list is the same as that shown in FIG.

That is, the distance measuring unit 1650 measures the position of the information terminal 10 measured by the position calculating unit 1620 and the coordinates of each transmitting station installed in the area where the information terminal 10 is located, (Step S301).

Meanwhile, the signal strength measuring unit 1660 measures the intensity of the signal received from each transmitting station installed in the area where the information terminal 10 is located, to the information terminal 10 (S303). Here, the received signal strength may be measured for at least one broadcast channel served at each transmission station, for a common channel used at each transmission station, or for each broadcast channel served at each transmission station And a method of calculating the average of these values.

Thereafter, the candidate extractor 1670 extracts, based on the distance information measured in step S301, the received signal strength measured in step S303, the distance information measured in steps S301 and S303, and the received signal strength, And generates a candidate list (S305). The candidate list may be a candidate list that is adjacent to the information terminal 10 or that has a higher received signal strength to the information terminal 10 or has a higher received signal strength to the information terminal 10, It is preferable to arrange them in the order according to the result.

In addition, the signal strength measurement process S303 of FIG. 8 may be performed as shown in FIG. 9 to improve the accuracy of the handover.

9, in order to measure the strength of the signal received from each transmitting station installed in the area where the information terminal 10 is located to the information terminal 10 a plurality of times, the number of signal strength measurement counts is started (S401) (N) is exceeded (S403). If it is determined in step S403 that the number of times of measurement does not exceed the preset number of times, the signal strength transmitted from the transmitting station to the information terminal 10 is measured (S405), and the process proceeds to step S401. .

If it is determined in step S403 that the number of times of measurement is equal to or greater than the preset number of times, that is, after the signal strength measurement is completed by a preset number of times, an average value of the measured signal strength is calculated (S407).

On the other hand, when determining the priority in step S305 of FIG. 8, if the distance between the information terminal 10 and the transmitting station measured in step S301 is weighted by the signal strength (or the average value) measured in step S303, It is of course possible to determine the over-target transmission station.

In this manner, the information terminal 10 includes the dual DMB receiving module 150, and handover is performed through remaining front end units other than the front end unit that receives the broadcast signal currently being viewed, The user is able to watch the broadcast or the other broadcast without interruption.

Thus, those skilled in the art will appreciate that the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics thereof. It is therefore to be understood that the embodiments described above are to be considered in all respects only as illustrative and not restrictive. The scope of the present invention is defined by the appended claims rather than the detailed description and all changes or modifications derived from the meaning and scope of the claims and their equivalents are to be construed as being included within the scope of the present invention do.

According to the present invention, when an information terminal equipped with a dual DMB receiving module moves on a boundary between regions, it can continuously view a broadcasting signal being watched, thereby improving the quality of a DMB broadcasting service. Therefore, the number of DMB service subscribers can be greatly increased.

In addition, when the information terminal moves from one region to another, transmission terminal information of each region is stored in the information terminal, and the user can select the broadcasting to be viewed by providing the available transmission terminal information to the candidate list, thereby improving the service satisfaction .

1 is a view for explaining a concept of a handover according to the present invention;

2 is a configuration diagram of an information terminal according to the present invention;

FIG. 3 is a detailed configuration diagram of the dual DMB receiving module shown in FIG. 2,

FIG. 4 is a detailed configuration diagram of the handover module shown in FIG. 2,

FIG. 5 is an example of a transmission site information table applied to the present invention,

6 is a flowchart illustrating a handover method according to an embodiment of the present invention.

FIG. 7 is a flowchart illustrating a handover method according to another embodiment of the present invention. FIG.

FIG. 8 is a detailed flowchart of the candidate extraction process shown in FIG. 7,

9 is a detailed flowchart of the signal strength measurement process shown in FIG.

Description of the Related Art [0002]

10: Information terminal 110:

120: memory 130: application service module

140: GPS receiving module 150: Dual DMB receiving module

160: handover module 1610: handover determination unit

1620: Position calculation unit 1630: Transmitting station search unit

1640: connection switching unit 1650: distance measuring unit

1660: signal strength measuring unit 1670: candidate extracting unit

Claims (32)

An information terminal connected to a dual DMB (Digital Multimedia Broadcasting) receiving module having a GPS (Global Positioning System) receiving module and a plurality of front end units, A memory for storing DMB transmission station information installed in each area; And When a handover is required for outputting a DMB broadcasting signal received by a front end unit among the plurality of front end units, A handover module for connecting to at least one of the searched DMB transmission stations by another front end unit other than the front end unit for receiving the currently output DMB broadcasting signal when one DMB transmission station is searched; . The method according to claim 1, Wherein the handover module comprises: a position calculation unit for measuring a current position of the information terminal using the GPS reception module; A transmission station search unit for referring to a DMB transmission station installed in an area where the information terminal is located, by referring to the current location of the information terminal and the DMB transmission site information measured by the location calculation unit; And When the information terminal searches for at least one DMB transmission station for transmitting the same signal as the currently output DMB broadcasting signal, the front end unit for receiving the currently output DMB broadcasting signal, A connection switching unit for allowing the other front end unit to connect to at least one of the searched DMB transmission stations; The information terminal comprising: 3. The method of claim 2, Wherein the handover module further comprises a handover determination unit for determining whether to operate the handover module according to whether a handover is required. 3. The method according to claim 1 or 2, The DMB transmitting station information includes a transmitting station identifier for identifying each DMB transmitting station, location information of each DMB transmitting station, information of each broadcasting channel served by each DMB transmitting station, and frequency information allocated to each broadcasting channel Characterized in that said information terminal. 5. The method of claim 4, Wherein the location information of each DMB transmission station is latitude and longitude coordinates. 3. The method of claim 2, The handover module comprises: A distance measurement unit for calculating a distance from each of the DMB transmission stations viewed by the transmission station searching unit to the information terminal by referring to the position information of the information terminal measured by the position calculating unit and the DMB transmission station information searched by the transmission station searching unit, part; And And a candidate extracting unit for extracting a DMB transmission destination list of the handover target with reference to a calculation result of the distance measuring unit, Wherein the connection switching unit refers to the inquiry result of the transmission station searching unit and selects any one of the DMB transmission station lists extracted by the candidate extracting unit and a channel to be served by the selected DMB transmission station, Wherein the other front end units except for the DMB broadcasting signal reception front end unit are connected to the channel of the selected DMB transmission center. The method according to claim 6, Wherein the handover module further includes a signal strength measurement unit for measuring a strength of a signal received from the DMB transmitting station to the information terminal, The candidate extracting unit extracts a list of DMB transmission destination DMBs for handover with reference to the calculation result of the distance measuring unit or the measurement value of the distance measuring unit as a weight value to the measured value of the signal strength measuring unit, And the information terminal. 8. The method of claim 7, Wherein the signal strength measuring unit measures the received signal strength from the DMB transmitting station inquired by the transmitting station searching unit to the information terminal a plurality of times and calculates an average value. 8. The method according to claim 6 or 7, Wherein the connection switching unit determines a priority order from a list of DMB transmission stations extracted by the candidate extracting unit, selects a DMB transmission station having a highest priority, and selects one of the channels served by the selected DMB transmission station from the connection switching unit or the user Selects one front end unit other than the front end unit for receiving the currently output DMB broadcasting signal to connect to the selected channel. 10. The method of claim 9, Wherein the priority of the DMB transmitting station is determined by weighting the distance to the information terminal or the distance from the information terminal to the signal strength to the information terminal. 8. The method according to claim 6 or 7, The connection switching unit presents the list of DMB transmission stations extracted by the candidate extracting unit to the user and selects one of the channels served by the selected DMB transmission station after the user selects one of the DMB transmission stations, And the other front end unit except for the front end unit for receiving the DMB broadcasting signal connects to the selected DMB transmission center. 3. The method of claim 2, The handover module comprises: A signal strength measuring unit measuring a received signal strength from the DMB transmitting station to the information terminal; And And a candidate extracting unit for extracting a DMB transmission destination list of the handover target with reference to a measurement result of the signal strength measuring unit, The connection switching unit refers to the inquiry result of the transmission station search unit and when the information terminal does not have a new DMB transmission station for transmitting the same signal as the currently outputted DMB broadcasting or if there are a plurality of new DMB transmission stations, List is selected and one of the front-end units excluding the front-end unit for receiving the currently output DMB broadcasting signal is selected as the selected DMB transmission center To the information terminal. 13. The method of claim 12, Wherein the signal strength measuring unit measures the received signal strength from the DMB transmitting station inquired by the transmitting station searching unit to the information terminal a plurality of times and calculates an average value. 13. The method of claim 12, Wherein the connection switching unit determines a priority order according to the signal strength from the DMB transmission station list extracted by the candidate extracting unit and selects a DMB transmission station having the highest priority and selects any one of the channels served by the selected DMB transmission station Selects one front end unit other than the front end unit for receiving the currently output DMB broadcasting signal to be connected to the selected channel according to the selection by the switching unit or the user. 13. The method of claim 12, The connection switching unit presents the list of DMB transmission stations extracted by the candidate extracting unit to the user and selects one of the channels served by the selected DMB transmission station after the user selects one of the DMB transmission stations, And the other front end unit except for the front end unit for receiving the DMB broadcasting signal connects to the selected DMB transmission center. 1. A handover method in an information terminal connected to a dual DMB (Digital Multimedia Broadcasting) receiving module having a Global Positioning System (GPS) receiving module and a plurality of front end units, A first step of storing DMB transmitting station information installed in each region; A second step of measuring a current position of the information terminal as the information terminal which receives and outputs the DMB broadcasting signal is moved by one of the plurality of front end modules; A third step of referring to a DMB transmission station installed in an area where the information terminal is located by referring to the DMB transmission station information; A fourth step of checking whether there is a DMB transmission station for transmitting the same broadcasting signal as the DMB broadcasting signal currently output by the information terminal, among the DMB transmission stations checked in the third step; And If a DMB transmission station for transmitting the same broadcasting signal exists as a result of the fourth step, the connection is switched by another front-end unit excluding the front-end unit for receiving the currently output DMB broadcasting signal; And a handover method in the information terminal. 17. The method of claim 16, The fifth step may include a fifth step of determining a priority order for each of the plurality of DMB transmission stations when a plurality of DMB transmission stations for transmitting the same broadcasting signal exist as a result of the fourth step, And Selects a DMB transmission station having a highest priority based on the priority and switches the connection to the selected DMB transmission station by another front end unit excluding the front end unit for receiving the currently output DMB broadcasting signal, (5-2) receiving the same broadcast signal as the currently output broadcast signal; And a handover method in the information terminal. 18. The method of claim 17, The determining of the priority may include assigning the distance to a distance from each of the plurality of DMB transmitting stations to the information terminal or a received signal strength to the information terminal or a received signal strength to the information terminal Wherein the step of determining the handover method comprises the steps of: 19. The method of claim 18, Wherein the received signal strength from each of the plurality of DMB transmitting stations to the information terminal is an average value of the received signal strength from each of the plurality of DMB transmitting stations to the information terminal. 17. The method of claim 16, If it is determined in the fourth step that there is no DMB transmitting station for transmitting the same broadcasting signal, a sixth candidate list is generated based on the distance from each DMB transmitting station installed in the area where the information terminal is located to the information terminal step; And One of the DMB transmission stations is selected from among the candidate lists and one of the channels served by the selected DMB transmission station is selected so that the other front end unit except the front end unit for receiving the currently output DMB broadcasting signal A seventh step of switching the connection to the selected channel of the selected DMB transmitting station by the seventh step; And transmitting the handover request message to the information terminal. 21. The method of claim 20, The sixth step includes a sixth step of measuring a distance from a current location of the information terminal to each DMB transmission site installed in an area where the information terminal is located; A step 6-2 of measuring a received signal strength from each DMB transmitting station installed in an area where the information terminal is located to the information terminal; And A sixth step of generating a candidate list by referring to the measurement result of step 6-1 and the measurement result of step 6-2; And transmitting the handover request message to the information terminal. 22. The method of claim 21, The step 6-3 is a step of generating a list of DMB transmission stations adjacent to the information terminal or a list of DMB transmission stations according to a result of weighting the distance between the information terminal and the signal strength of the information terminal, And a handover method in the information terminal. 22. The method of claim 21, The step 6-2 is a step of calculating an average value by measuring a received signal strength from each DMB transmitting station installed in an area where the information terminal is located to the information terminal by a predetermined number of times, Wherein the step 6-3 is a step of generating a candidate list by referring to the measurement result of the step 6-1 and the measurement result of the step 6-2. 21. The method of claim 20, The seventh step determines a priority order from the candidate list to select a DMB transmission station having the highest priority and selects one of the channels served by the selected DMB transmission station, And switching the connection to the selected channel by the other front end unit excluding the front end unit for receiving the DMB broadcasting signal to be output. 25. The method of claim 24, Wherein the priority of the DMB transmitting station is determined by assigning a distance between the information terminal and a distance to the information terminal or a signal intensity to the information terminal as a weight, . 21. The method of claim 20, The seventh step is a step of presenting the candidate list to the user and selecting one of the DMB transmission sites by the user and selecting one of the channels served by the selected DMB transmission station, And switching the connection to the selected channel by the other front-end unit excluding the credit front-end unit. 17. The method of claim 16, If it is determined in the fourth step that there is no DMB transmitting station for transmitting the same broadcasting signal, a candidate list is generated on the basis of the received signal strength from each DMB transmitting station installed in the area where the information terminal is located Step 6; And One of the DMB transmission stations is selected from among the candidate lists and one of the channels served by the selected DMB transmission station is selected so that the other front end unit except the front end unit for receiving the currently output DMB broadcasting signal A seventh step of switching the connection to the selected channel of the selected DMB transmitting station by the seventh step; And transmitting the handover request message to the information terminal. 28. The method of claim 27, The sixth step includes a sixth step of calculating an average value by measuring a received signal strength from each DMB transmitting station installed in an area where the information terminal is located to a predetermined number of times, And And a sixth step of generating a candidate list by referring to the average value measured in the step 6-1, And the seventh step is a step of switching the connection to any one of the candidate lists generated in step 6-2. 29. The method of claim 27 or 28, The seventh step determines a priority order from the candidate list to select a DMB transmission station having the highest priority and selects one of the channels served by the selected DMB transmission station, And switching the connection to the selected channel by the other front end unit excluding the front end unit for receiving the DMB broadcasting signal to be output. 29. The method of claim 27 or 28, The seventh step is a step of presenting the candidate list to the user and selecting one of the DMB transmission sites by the user and selecting one of the channels served by the selected DMB transmission station, And switching the connection to the selected channel by the other front-end unit excluding the credit front-end unit. 17. The method of claim 16, Wherein the DMB transmission station information includes a transmitter identifier for identifying each DMB transmitter, location information of each DMB transmitter, broadcast channel information served by each DMB transmitter, and frequency information allocated to each broadcast channel. A handover method in a terminal. 32. The method of claim 31, Wherein the location information of each DMB transmission station is latitude and longitude coordinates.

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