KR100979563B1 - DMB Handover Method and System Using Zone-Based Channel Quality Information - Google Patents

Abstract

The present invention relates to a handover method and system using regional channel quality information in a digital multimedia broadcasting network. A method for performing handover in a digital multimedia broadcasting receiver according to the present invention comprises: maintaining channel quality information for each region to maintain channel quality information for each region in a predetermined recording area; A service quality checking step of checking whether a channel quality for a current service channel satisfies a preset channel quality threshold value; A search target channel selection step of selecting a search target channel for handover with reference to the region-specific channel quality information table if it is not satisfied; And performing a handover according to the channel quality of the selected discovery target channel. Accordingly, the present invention has an advantage of providing a handover method capable of performing handovers more quickly and effectively by using previously collected regional channel quality information.

Digital multimedia broadcasting, handover, reception quality, channel quality information, frequency search

Description

Digital multimedia broadcasting handover method and system using regional channel quality information {DMB Handover Method and System Using Zone-Based Channel Quality Information}

The present invention relates to a digital multimedia broadcasting handover method and system using channel quality information for each region, and more particularly, to maintain the channel quality information for each region pre-measured and collected at a receiving terminal and to use the channel quality information. The present invention relates to a digital multimedia broadcasting handover method and system using local channel quality information capable of performing a faster and more effective handover at the same time.

Recently, the viewing pattern of TV is greatly changed due to the convergence of broadcasting and communication technologies. The advent of Digital Multimedia Broadcasting (DMB), which enables users to enjoy clear broadcasts on high-speed trains, enables the viewing of personalized broadcasts that are not limited by time and space.

In other words, the advent of DMB is no longer needed to hurry up in front of the TV in the living room to watch dramas or sports broadcasts.

In Korea, terrestrial DMB has recently been activated, starting with the initial satellite DMB. Terrestrial DMB refers to providing a digital mobile multimedia broadcasting service to a subscriber mobile receiver using a terrestrial repeater.

Here, the terrestrial repeater may be assigned different frequencies for each zone, and the area serviced by the terrestrial repeater, that is, cell coverage is limited.

To ensure service continuity, the DMB receiver must perform DMB handover when moving out of the cell coverage of the currently connected terrestrial repeater to the service area of another terminator.

For DMB handover, the DMB receiver may scan the DMB signals received from the adjacent terrestrial repeater and check the currently available DMB signals. At this time, the DMB receiver processes the DMB handover in consideration of the signal strength, service ID, ensemble ID, etc. of the received DMB signal.

However, the conventional DMB receiver checks all currently received DMB signals in no particular order to determine the DMB handover, and thus, it takes a long time until the DMB handover is completed. In particular, service disruption due to handover delay could occur in certain regions. As a result, there is a problem that the overall DMB service quality is lowered.

An object of the present invention for solving the problems of the prior art as described above is to provide a DMB handover method using the regional quality information.

Another object of the present invention is to enable continuous broadcasting viewing to DMB viewers moving to other viewing areas, and to provide a high quality broadcasting service required by the viewers.

It is still another object of the present invention to provide a DMB receiver capable of performing a faster handover by loading previously collected channel quality information for each region in a DMB receiver.

Another object of the present invention is to provide a method and system for transmitting the same to the DMB receiver when updating a channel quality table for each region.

According to an embodiment of the present invention, a method of performing handover in a digital multimedia broadcasting terminal is disclosed.

A method for performing handover in a digital multimedia broadcasting terminal according to an embodiment of the present invention comprises: maintaining channel quality information for each region for maintaining channel quality information for each region in a predetermined recording area; A service quality checking step of checking whether a channel quality for a current service channel satisfies a preset channel quality threshold value; A search target channel selection step of selecting a search target channel for handover with reference to the region-specific channel quality information table if it is not satisfied; And performing a handover according to the channel quality of the selected discovery target channel.

According to another embodiment of the present invention, a digital multimedia broadcasting terminal for performing faster and more effective handover is disclosed.

According to an embodiment of the present invention, a digital multimedia broadcasting terminal includes: a database for maintaining channel quality information and service relationship information for each region; A search frequency selection unit which determines a search order of a handover target frequency by using a current location of the digital multimedia broadcasting terminal and channel quality information of each region; A service continuity judging unit verifying whether the frequency to be searched can support the service continuity of the current service channel with reference to the service relationship information; And a quality measuring unit which determines whether to initiate a handover by measuring the quality of the DMB signal.

The present invention has an advantage of providing a DMB handover method using channel quality information for each region.

In addition, the present invention has the advantage of enabling a continuous broadcast viewing to the viewer using the DMB service, and providing a high quality broadcast service required by the viewer.

In addition, the present invention has an advantage of providing a DMB terminal capable of performing faster and optimized handover by loading previously collected regional channel quality information in a DMB receiver.

In addition, the present invention has an advantage of providing a method and system for transmitting the same to the DMB receiver when updating the channel quality table for each region.

Through the above advantages, the present invention can expect the effect of allowing more viewers to use the DMB service.

As the invention allows for various changes and numerous embodiments, particular embodiments will be illustrated in the drawings and described in detail in the written description. However, this is not intended to limit the present invention to specific embodiments, it should be understood to include all modifications, equivalents, and substitutes included in the spirit and scope of the present invention.

The terms first, second, etc. may be used to describe various components, but the components should not be limited by the terms. The terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, the first component may be referred to as the second component, and similarly, the second component may also be referred to as the first component.

The term and / or includes any item of a plurality of related items or a combination of a plurality of related items. The terminology used herein is for the purpose of describing particular example embodiments only and is not intended to be limiting of the present invention. Singular expressions include plural expressions unless the context clearly indicates otherwise.

In this application, the terms "comprising" or "mounted" and "mounted" are intended to indicate that there is a feature, number, step, action, component, part, or combination thereof described on the specification, one Or other features or numbers, steps, operations, components, parts or combinations thereof in any way should not be excluded in advance.

Unless defined otherwise, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art. Terms such as those defined in the commonly used dictionaries should be construed as having meanings consistent with the meanings in the context of the related art, and are not construed in ideal or excessively formal meanings unless expressly defined in this application. Do not.

Other aspects, features, and advantages other than those described above will become apparent from the following drawings, claims, and detailed description of the invention.

Hereinafter, a preferred embodiment of a digital multimedia broadcasting handover method and system using local channel quality information according to the present invention will be described in detail with reference to the accompanying drawings.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Reference will now be made in detail to the preferred embodiments of the present invention, examples of which are illustrated in the accompanying drawings, wherein like reference numerals refer to the like elements throughout.

1 is a structure of a digital multimedia broadcasting network for explaining a method of performing handover using regional channel quality information according to an embodiment of the present invention.

As shown in FIG. 1, a portable receiver with a digital multimedia broadcasting function, hereinafter referred to as a "DMB (Digital Multimedia Broadcating) terminal 110" business card, is a DMB broadcasting signal transmitted by the broadcasting station 120 to the DMB base station. 130 or via the DMB repeater 140. Here, the DMB repeater 140 solves the shadow area problem and amplifies and transmits a broadcast signal received from the DMB base station 130 to expand cell coverage for a broadcast service.

The DMB terminal 110 disclosed in the present invention may include a mobile phone, a PDA, a notebook computer, a vehicle receiver, etc. equipped with a DMB function.

The broadcast station 120 encodes and multiplexes the previously generated broadcasting content in a manner defined in the DMB broadcasting standard, where the wired channel may be configured using a coaxial cable or an optical cable. Transmit to the DMB base station 130 via a radio channel, eg, a broadcast satellite.

In addition, the broadcasting station 120 may receive the processed content from the broadcast content providing unit 160 for processing the content to be suitable for a specific broadcast service.

In particular, the broadcast signal may include not only user data but also service relationship information in which mutual mapping relationships between ensemble, frequency, and service for DMB handover are defined.

Definitions and interrelationships for the ensemble, frequency, and service will be described in detail with reference to FIGS. 3 to 6 to be described later.

The DMB terminal 110 according to an embodiment of the present invention may receive a regional channel quality information table through a predetermined DMB broadcast return channel and maintain it in a predetermined recording area.

Here, the return channel is a bidirectional control channel set between the broadcasting station 120 and the DMB terminal 110 and may be set through a mobile communication system.

In general, the mobile communication system may be composed of a switch, a base station controller, a base station for mobile communication. A detailed description of the mobile communication system is not an essential component for describing the idea disclosed by the present invention and will be omitted below.

The channel quality information table for each region includes channel quality information for each frequency measured through field tests. Here, the channel quality information includes information on reception quality measured for each channel and service of the DMB service, and includes electric field strength (dBm or dBuV / m), bit error rate (BER), and video service for each channel or service. It may include various items related to reception quality such as reception quality (Video Frame Error Rate, TS Packet Error Rate), audio service reception quality (Audio Frame CRC Error), data service reception quality (Data Packet CRC Error Rate).

The channel quality information for each frequency according to an embodiment of the present invention is collected for each region in the form of a rectangular cell in which the entire DMB broadcasting service area is divided into a plurality of small units. Used for screening purposes.

Each rectangular cell is assigned a unique region identifier for the entire DMB service area, and the channel quality information table for each region includes location information corresponding to the region identifier, where the location information may be in latitude and longitude ranges. It may include at least one frequency information used in the region corresponding to the region identifier and the measured channel quality measurement information for each frequency.

According to the present invention, the DMB terminal 110 initiates a handover procedure when the reception quality of the currently tuned broadcast service channel does not satisfy a preset threshold.

When the handover procedure is started, the DMB terminal 110 acquires its current location information and checks the region identifier corresponding to the obtained location information with reference to the regional channel quality information table.

Next, the DMB terminal 110 selects a frequency to be searched for by referring to channel quality information for each frequency corresponding to the identified region identifier, and performs continuity of the currently tuned service among at least one service corresponding to the selected frequency. Check whether there is a service that can be supported.

If present, the DMB terminal 110 performs a handover to a channel capable of supporting the continuity of the service. In this case, the search priority may be determined based on the channel quality information. For example, the frequency search order may be determined in order of good channel quality.

Of course, if there is no service that can support the continuity of the currently tuned service, the search for the frequency having the next higher priority is started.

The regional channel quality information table according to another embodiment of the present invention may include a cell identifier of at least one mobile communication base station covering a service area corresponding to the corresponding region identifier. The DMB terminal 110 may obtain information on the current access cell identifier and the neighbor cell identifier through a control signal received from a mobile communication base station, for example, a BCH (Broadcasting Channel) of WCDMA. And a region identifier corresponding to the neighbor cell identifier through the region-specific channel quality information table.

According to another embodiment of the present invention, it should be noted that service relationship information for handover received through the fast information channel (FIC) may also be maintained in the DMB terminal 110 through the return channel in advance. In this case, since the DMB terminal 110 does not need to periodically decode the FIC, the DMB terminal 110 may perform handover faster.

In addition, the DMB terminal 110 does not need to consume a separate power for FIC decoding, thereby reducing the battery consumption.

2 is an example of frequency allocation of a DMB service according to an embodiment of the present invention.

Referring to FIG. 2, a general DMB service may cover a relatively large area through one frequency band. For example, FIG. 2 shows that Chungcheongnam-do and Chungcheongbuk-do are assigned the 11th frequency and Jeollanam-do the eighth frequency.

In particular, adjacent frequencies may overlap each other, and handover may occur frequently in the overlapped periods. For example, the DMB terminal located at the border region of Chungcheongnam-do and Gyeonggi-do may perform handover in a section where the eighth frequency, the twelfth frequency, and the eleventh frequency overlap.

In particular, the DMB service network illustrated in FIG. 2 reuses frequencies so that the same frequencies do not overlap in order to maximize frequency use efficiency. For example, it can be seen that the thirteenth frequency allocated to Gangwon-do is used in some regions of Jeju Island.

In general, when a conventional DMB terminal is located in a region where a plurality of frequencies overlap, if it is determined that handover is necessary, the conventional DMB terminal has to search for all frequencies used in the region. Accordingly, there is a problem in that conventionally, service continuity due to handover delay cannot be guaranteed.

In order to solve the above problem, the present invention has the advantage of maintaining the pre-collected regional channel quality information on the DMB terminal and selectively performing a frequency search using the same. That is, the present invention has an advantage of maintaining the continuity of the service or minimizing the disconnection of the service through faster handover.

3 is a view for explaining a DMB frequency allocation method according to an embodiment of the present invention.

As shown in FIG. 3, the frequency bands allocated for the DMB service are channel 8 310 and channel 12 320. Here, each channel is divided into an A band, a B band, and a C band, and a predetermined guard band is allocated between each band to avoid inter-frequency interference.

For example, channel 12 320 is divided into 12A band 321, 12B band 322, and 12C band 323, and broadcast service providers for each band may be allocated MBC, KBS, and SBS, respectively. .

The broadcast service provider may configure various broadcast service channels by subdividing the allocated bands. For example, the KBS may provide an ensemble of KBS star, KBS heart, and KBS TTI through the allocated 12B band 322. Here, the ensemble may be uniquely identified by the ensemble identifier as a set of services transmitted in a specific frequency band.

The services constituting the ensemble include audio, video, and data services, and may be composed of one or more service components.

The service is identified by the service identifier, and the DMB terminal preferably maintains the continuity of the service by transitioning to a frequency where the same service as the service currently being viewed is provided upon handover between frequencies.

4 is a diagram for explaining inter-frequency handover for the same ensemble according to an embodiment of the present invention.

Here, the same ensemble means that a set of services provided at different frequencies are the same. That is, the ensemble identifiers are the same.

Of course, services corresponding to each other included in two identical ensembles have the same service identifier.

Accordingly, in order to perform handover between frequencies having the same ensemble, relationship information between the ensemble and the frequencies is required.

Referring to FIG. 4, the ensemble identifier 0xE084 of the 11B band allocated to the Chungcheong region is the same as the ensemble identifier 0xE084 of the 12B band allocated to the Chonbuk region. Therefore, the DMB terminal moving from the Chungjeong area to the Jeonbuk area needs to shift the reception frequency from the 11B band to the 12B band while maintaining the current service when handover between frequencies.

FIG. 5 is a diagram for explaining handover between frequencies for different ensembles according to an embodiment of the present invention.

As shown in FIG. 5, it can be seen that the ensemble identifier 0xE044 corresponding to the 12B band of the Seoul area is different from the ensemble identifier 0xE084 corresponding to the 11B band of the Chungcheong area.

That is, it can be seen that the combination of services provided in the Seoul area and the Chungcheong area is different from each other. However, there is the same service in each ensemble, for example KBS star and KBS TTI.

When performing an inter-frequency handover to a region where the ensemble is different, the DMB terminal checks whether the same service as the service currently being viewed in the serving cell 510 is served by the target cell 520.

As a result of the check, when the same service is supported by the target cell 520, the DMB terminal transitions to the frequency 11B corresponding to the target cell 520 while maintaining the service provided to the serving cell 510.

Therefore, when different ensembles and the same service identifier exist, the DMB terminal may perform handover between frequencies by using mapping information about [ensemble: frequency] and [service: ensemble].

FIG. 6 is a diagram for describing a handover method between frequencies in a case where frequencies, ensembles, and services are different from each other according to an embodiment of the present invention.

As shown in FIG. 6, it can be seen that the ensemble identifier and service identifier allocated to the 11C band of the Chungcheong region are different from the ensemble identifier and service identifier allocated to the 12C band of the Jeonbuk region.

When performing an inter-frequency handover to a region where the ensemble is different, the DMB terminal checks whether the same service as the service currently being viewed in the serving cell 610 is serviced by the target cell 620.

As a result of the check, when the same service is not supported by the target cell 620, the DMB terminal checks whether a service composed of the same service component as the currently provided service exists in the target cell 620.

As a result of the check, if there is a service configured with the same service component, the DMB terminal performs handover to the corresponding service of the target cell 620. For example, when a DMB terminal moving from Chungjeong area to Jeonbuk area receives a TV service in Chungcheong area and performs handover, it performs handover to TV service in Jeonbuk area.

Therefore, when different ensemble and the same service identifier does not exist, the DMB terminal performs handover between frequencies using respective mapping information for [ensemble: frequency], [service: ensemble], and [service: service]. can do.

7 is a view for explaining a region identifier mapping method according to an embodiment of the present invention.

Referring to FIG. 7, channel quality statistics information for each region according to the present invention may be collected for each region identifier.

The region identifier is a value for uniquely identifying a plurality of rectangular cells generated by dividing the whole country into predetermined offset values along the latitude and longitude axes.

The longitude offset 710 and latitude offset 720 values for determining the size of the rectangular cell may be determined to be predetermined values by the DMB service provider collecting channel quality statistics.

It is desirable for the DMB service provider to collect channel quality information for a narrower service area by setting the offset value as small as possible.

However, when the offset value is small, there may be a problem that a large amount of memory must be mounted in the DMB terminal because the collected channel quality information for each region is huge.

To solve this problem, the DMB terminal according to an embodiment of the present invention maintains only partial regional channel statistics information corresponding to the current location (for example, partial regional statistical information may be Seoul regional channel statistical information). In the case of moving out of the service area covered by previously stored regional channel statistics information, for example, moving to the Chungcheong region, the regional channel statistics information corresponding to the current position through the return channel, for example, the Chungcheong region channel May receive statistical information. In this case, the DMB terminal preferably deletes previously stored Seoul channel statistics information from the corresponding memory.

However, the partial regional channel statistical information received through the return channel preferably includes channel quality information of some overlapping sections to support continuity of the service.

Hereinafter, a service area corresponding to the partial regional channel statistics information will be referred to as a "cluster channel statistics area".

Referring to FIG. 7, the first cluster channel statistics area 730 and the second cluster channel statistics area 740 may include a cluster overlapping section 750.

According to another embodiment of the present invention, a broadcast service provider may perform a filter test for updating channel quality information according to a change in DMB network configuration, for example, expansion of a DMB transmitter and a DMB repeater. A new version can be assigned to regional channel quality information. Thereafter, the broadcasting station may transmit the updated version information to the DMB terminal through the return channel.

If the DMB terminal receives the updated version received through the return channel higher than the version maintained in the current terminal, the DMB terminal may acquire the updated regional channel quality information through the return channel.

8 is a channel quality information table for each region according to an embodiment of the present invention.

As shown in FIG. 8, the regional channel quality information table 800 includes a local rectangle identity 810, a latitude and longitude range 820 corresponding to the region identifier, a cell identifier 830, and a frequency band ( 840 and channel quality information 850.

Here, the channel quality information 850 may include an electric field strength (dBm or dBuV / m) measured through a field test, a data error rate, shadow area identification information, and the like.

The data error rate may be broken down by broadcast service type, and may include a bit error rate (BER) and a block error rate (BLER) for each service type.

The shadow area identification information provides identification information that can easily distinguish whether a specific frequency band corresponding to a specific area identifier is a range by comparing the electric field strength and data error rate measured in the corresponding frequency band with a preset reference value. For example, the shadow area identification information may be set to 'YES' for the shadow area or 'NO' for the shadow area.

9 is a flowchart illustrating a procedure for performing handover in a DMB terminal according to an embodiment of the present invention.

Referring to FIG. 9, the DMB terminal maintains a regional channel quality information table in a predetermined recording area (S902).

The DMB terminal decodes the broadcast channel to obtain service relationship information for the corresponding service area and stores it in a predetermined recording area (S904).

The DMB terminal measures the channel quality of the service currently being viewed (S906), and compares whether the measured channel quality satisfies a predetermined channel quality threshold value (S908).

As a result of comparison, the DMB terminal measures its current location using the GPS receiving module (S910), and selects the highest priority search target channel using the measured location and regional channel quality information table (S912).

The DMB terminal measures channel quality for the selected channel (S914), and checks whether the measured channel quality satisfies a predetermined channel quality threshold for handover (S916).

As a result of the check, the DMB terminal performs the handover to the selected channel (S918).

If the quality of the selected channel does not satisfy the predetermined channel quality threshold in step 916, the DMB terminal selects a frequency band having the next higher channel quality with reference to the regional channel quality information table (S920). In step 914, the process is performed.

According to another embodiment of the present invention, the current position of the DMB receiver is TII contained in FIG0 / 22, where the TII includes longitude / latitude information and transmission delay time information of the corresponding DMB transmitting station. It is possible to estimate their position or to calculate the direction of movement.

Therefore, it should be noted that the DMB receiver according to the present invention can estimate its current position without mounting a separate GPS receiver module. In the current DMB system, basic information for handover may be repeatedly transmitted through a fast information channel (FIC) configured with a fast information group (FIG).

In particular, TII database information is transmitted in FIG. 0/22, and the DMB receiver may acquire longitude / latitude coordinate information and transmission delay time information of the corresponding DMB transmitter by decoding the FIB Type 0/22. However, FIG Type 0/22 has a feature of selectively transmitting information in a DMB system.

According to another embodiment of the present invention, when the DMB receiver is equipped with a mobile communication function, for example, at least one of communication functions such as CDMA / GSM / WCDMA, the current location is determined by the base station to which it is currently connected. It can be estimated using a cell identifier.

In order to facilitate retrieval of a region identifier corresponding to the cell identifier, as shown in FIG. 8, the region-specific channel quality information table according to the present invention may include at least one cell identifier corresponding to the region identifier. . In this case, the DMB receiver may identify a region identifier corresponding to the cell identifier received from the access base station with reference to the channel quality information table, and perform DMB handover using the channel quality information corresponding to the region identifier. .

10 is a flowchart illustrating a search procedure for handover according to an embodiment of the present invention.

In more detail, FIG. 10 is a diagram for describing a detailed procedure corresponding to reference numeral 930 of FIG. 9.

Referring to FIG. 10, the DMB terminal selects a region identifier corresponding to the measured position by referring to a region-specific channel quality information table (S1002).

The DMB terminal selects a frequency having the best channel quality according to the region identifier with reference to the region-specific channel quality information table (S1004).

The DMB terminal extracts service relationship information corresponding to the selected frequency (S1006), and checks whether the continuity of the currently viewed service can be supported through the selected frequency with reference to the extracted service relationship information (S1008).

As a result of the check, if the continuity of the service can be supported, the DMB terminal measures the channel quality for the selected frequency (S1010), and checks whether the measured channel quality satisfies a preset channel quality threshold value corresponding to the handover. (S1012).

As a result of the check, the DMB terminal performs the handover to the selected channel (S1014).

If it is not possible to support the continuity of the currently viewed service through the frequency selected in step 1008, the DMB terminal selects a frequency having the next higher channel quality with reference to the regional channel quality information table (S1016). Perform

In addition, when the channel quality measured in step 1012 does not satisfy the predetermined channel quality threshold value, the DMB terminal selects a frequency having the next higher channel quality with reference to the regional channel quality information table (S1016). Perform step 1006.

As described above with reference to FIGS. 9 and 10, the DMB terminal according to an exemplary embodiment of the present invention identifies a search target frequency for handover using a regional channel quality information table and service relationship information, and corresponds to the corresponding frequency. The frequency search order may be determined using the actually measured channel quality information.

In addition, the DMB terminal may perform handover to a channel capable of supporting the continuity of the service currently being viewed using the service relationship information.

That is, the DMB terminal according to the present invention has an advantage of performing a faster and more efficient inter-frequency handover.

11 is a functional block diagram of a DMB terminal according to an embodiment of the present invention.

As shown in FIG. 11, the DMB terminal according to an embodiment of the present invention includes a wireless interface unit 1110, a quality measuring unit 1120, a control unit 1130, a service continuity determining unit 1140, and service relationship information storage. The unit 1150, the position acquisition unit 1160, the search frequency selection unit 1170, the regional channel quality information storage unit 1180, and the playback unit 1190 may be included.

The wireless interface unit 1110 performs functions such as modulation and demodulation of a radio signal, signal amplification, data encoding and decoding, data multiplexing and demultiplexing, data error check, and reception signal field strength measurement. Can be.

For example, the wireless interface unit 1110 receives a GPS signal from the GPS satellite 1191 to calculate current location information of the DMB terminal, and receives a DMB broadcast channel transmitted by the DMB base station 1192 to provide service relationship information. And extracting location information and transmission delay time information of the DMB base station, extracting a cell identifier of the current access base station and a cell identifier of an adjacent channel by decoding a control signal transmitted by the mobile communication base station 1193, and a return channel. Through this, a function of acquiring channel quality information for each region may be performed.

The quality measuring unit 1120 compares the received electric field strength of the DMB broadcast signal measured by the wireless interface unit 1110 with a channel quality threshold value, which is a predetermined reference value for determining whether to start the handover procedure, and starts the handover procedure. A predetermined control signal (hereinafter, referred to as a handover start request signal) may be provided to the controller 1130.

In addition, the quality measuring unit 1120 measures the channel quality for a specific frequency according to the control signal of the control unit 1130 and compares the measured channel quality information with a predefined handover quality reference value to hand over the measured channel. It may be determined whether the channel is suitable for, and the determination result may be provided to the controller 1130.

The quality measuring unit 1120 according to another exemplary embodiment of the present invention calculates a data error rate (eg, includes BER and BLER) by using the data error check result, and the calculated data error rate corresponds to a predetermined criterion. The controller 1130 may provide the handover initiation request signal to the controller 1130 by determining whether it is satisfied.

The controller 1130 may control the search frequency selector 1170 to perform a frequency search according to the handover start request signal received from the quality measurer 1120.

The search frequency selector 1170 selects a search target frequency corresponding to the current location by referring to the channel quality information for each region stored in the regional channel quality information storage unit 1180 according to the control signal of the controller 1130, and then selects the selected frequency. Search priority for.

The position acquiring unit 1160 may provide basic information necessary for calculating the current position of the DMB terminal from the wireless interface unit 1110—for example, latitude and longitude information of the DMB terminal, latitude and longitude information of the DMB base station, transmission delay time information, And include at least one of cell identifier information, and calculate or estimate current location information of the DMB terminal using the collected basic information. In addition, the location acquisition unit 1160 may provide the search frequency selection unit 1170 with current location information of the DMB terminal calculated or estimated at the request of the search frequency selection unit 1170.

The service continuity verification unit 1140 determines whether the search target frequency selected by the search frequency selection unit 1170 according to the control signal of the controller 1130 can support the continuity of the service currently being viewed. Performs the function of judging with reference to).

Referring to FIG. 11, the wireless interface unit 1110 stores the service relationship information obtained from the DMB broadcasting channel in the service relationship information storage unit 1150 and the regional channel quality information table obtained through the return channel. The function of storing the quality information storage unit 1180 may be performed.

The controller 1130 according to the present invention performs a resource allocation and scheduling function, data and message processing function, etc. in the DMB terminal. In particular, the controller 2230 performs an overall process flow control function for handover.

The playback unit 1190 plays the user data received from the control unit 1190, where the user data includes audio, video, packet data, and the like.

Embodiments of the present invention include computer readable media including program instructions for performing various computer implemented operations. The computer readable medium may include program instructions, local data files, local data structures, or the like, alone or in combination. The media may be those specially designed and constructed for the purposes of the present invention, or they may be of the kind well-known and available to those having skill in the computer software arts.

Examples of computer-readable recording media include magnetic media such as hard disks, floppy disks, and magnetic tape, optical recording media such as CD-ROMs, DVDs, magnetic-optical media such as floppy disks, and ROM, RAM, flash memory, and the like. Hardware devices specifically configured to store and execute the same program instructions are included.

The medium may be a transmission medium such as an optical or metal wire, a waveguide, or the like for transmitting a signal specifying a program command, a local data structure, or the like. Examples of program instructions include not only machine code generated by a compiler, but also high-level language code that can be executed by a computer using an interpreter or the like.

Preferred embodiments of the present invention described above are disclosed for purposes of illustration, and those skilled in the art will be able to make various modifications, changes, and additions within the spirit and scope of the present invention. Additions should be considered to be within the scope of the following claims.

1 is a DMB network structure for explaining a method for performing handover using regional channel quality information according to an embodiment of the present invention.

2 is a frequency allocation example of a DMB service according to an embodiment of the present invention.

3 is a view for explaining a DMB frequency allocation method according to an embodiment of the present invention.

4 is a diagram for explaining inter-frequency handovers for the same ensemble according to one embodiment of the present invention;

5 is a diagram for explaining inter-frequency handovers for different ensembles according to one embodiment of the present invention;

FIG. 6 is a diagram for explaining a handover method between frequencies for a case where frequencies, ensembles, and services are different from each other according to an embodiment of the present invention; FIG.

7 is a view for explaining a region identifier mapping method according to an embodiment of the present invention.

8 is a channel quality statistics table for each region according to an embodiment of the present invention.

9 is a flowchart illustrating a procedure for performing handover in a DMB terminal according to an embodiment of the present invention.

10 is a flowchart illustrating a search procedure for handover according to an embodiment of the present invention.

11 is a functional block diagram of a DMB terminal according to an embodiment of the present invention.

* Key Drawing

110: DMB terminal

120: broadcasting station

130: DMB base station

150: mobile communication system

800: Channel quality information table by region

810: region identifier

840: frequency band

850: Channel Quality Information

1120: quality measuring unit

1130: control unit

1140: Service Continuity Determination Unit

1150: service relationship information storage unit

1160: position acquisition unit

1170: search frequency selector

1180: Channel quality information storage unit for each region

Claims (16)

A method for performing handover in a digital broadcast reception device, Maintaining regional channel quality information for maintaining regional channel quality information in a predetermined recording area-The regional channel quality information includes a region identifier for uniquely identifying a unit service region, location information corresponding to the region identifier, and the region identifier. First to Nth frequency information allocated to a corresponding service area and channel quality information measured according to the allocated frequency; A service quality checking step of checking whether a channel quality for a current service channel satisfies a preset channel quality threshold value; Measuring a current position of the digital broadcast reception device when it is not satisfied as a result of the checking; Selecting an area identifier corresponding to the current location by referring to the location information of the channel quality information for each area; Determining a frequency search order using channel quality information for each frequency corresponding to the selected region identifier; Checking whether there is a service channel capable of supporting the continuity of the current service channel with reference to previously stored service relationship information according to the determined frequency search order; And If there is a service channel supporting the continuity of the current service channel, performing a handover according to the channel quality of the service channel supporting the continuity of the current service channel, The service relationship information is mapping information on an ensemble, a frequency, and a service. And the ensemble is a set of services transmitted in a specific frequency band. delete The method of claim 1, And the location information is latitude and longitude information corresponding to the area identifier. The method of claim 1, The location information First to N-th cell identifiers of mobile communication base stations included in a service area corresponding to the area identifier The method of performing handover in a digital broadcast receiving apparatus further comprising a. The method of claim 1, The measured channel quality information includes at least one of electric field strength, received data error rate, and shadow area identification information of a received channel. delete delete The method of claim 1, Determining the frequency search order If the channel quality for each frequency is below a predetermined criterion, the method further comprises the step of excluding the frequency from the search target. The method of claim 1, The current position of the digital broadcast receiver is A method of performing a handover in a digital broadcast receiving apparatus, characterized by decoding any one of a fast information channel received from a digital broadcast transmitter, a control signal received from a mobile communication base station, and a GPS signal. A recording medium readable by an electronic device on which a program consisting of typed instructions for executing a handover method in a digital broadcast receiving device, Maintaining regional channel quality information for maintaining regional channel quality information in a predetermined recording area-The regional channel quality information includes a region identifier for uniquely identifying a unit service region, location information corresponding to the region identifier, and the region identifier. First to Nth frequency information allocated to a corresponding service area and channel quality information measured according to the allocated frequency; A service quality checking step of checking whether a channel quality for a current service channel satisfies a preset channel quality threshold value; Measuring a current position of the digital broadcast reception device when it is not satisfied as a result of the checking; Selecting an area identifier corresponding to the current location by referring to the location information of the channel quality information for each area; Determining a frequency search order using channel quality information for each frequency corresponding to the area identifier; Checking whether there is a service channel capable of supporting the continuity of the current service channel with reference to previously stored service relationship information according to the determined frequency search order; And If there is a service channel supporting the continuity of the current service channel, performing a handover according to the channel quality of the service channel supporting the continuity of the current service channel, The service relationship information is mapping information on an ensemble, a frequency, and a service. And the ensemble is a set of services transmitted in a specific frequency band. A database for maintaining channel quality information and service relationship information for each region, wherein the channel quality information for each region is assigned to a region identifier for uniquely identifying a unit service region, location information corresponding to the region identifier, and a service region corresponding to the region identifier. First to Nth frequency information and measured channel quality information corresponding to the assigned frequency; A position obtaining unit obtaining a current position of the digital broadcast receiving apparatus; A quality measuring unit configured to check whether a channel quality of a current service channel satisfies a preset channel quality threshold value and generate and output a handover start request signal; In accordance with the handover start request signal, an area identifier corresponding to the current location is selected by referring to the location information of the channel quality information for each region, and a frequency search order is performed using channel quality information for each frequency corresponding to the selected region identifier. Search frequency selection unit for determining; A service continuity judging unit verifying whether a frequency to be searched can support service continuity of a current service channel with reference to the service relationship information according to the determined frequency search order; And If there is a service channel supporting the continuity of the current service channel, the control unit for performing a handover according to the channel quality of the service channel supporting the continuity of the current service channel, The service relationship information is mapping information on an ensemble, a frequency, and a service. And the ensemble is a set of services transmitted in a specific frequency band. delete delete delete The method of claim 11, The location information further comprises a first to N-th cell identifier of the mobile communication base station included in the service area corresponding to the area identifier. The method of claim 11, And the channel quality information for each region is received from an access mobile communication base station through a predetermined broadcast return channel.

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