KR101104711B1 - Method and System for Acknowledging WiBro Network in Coverage of Satellite DMB Network - Google Patents

Abstract

The present invention relates to a method and system for recognizing a WiBro network in a satellite DMB network.

The present invention provides a method for recognizing a WiBro network to use a WiBro service in an area in which a satellite DMB network providing a DMB service is provided, the method comprising the steps of: (a) receiving a satellite DMB signal transmitted from the satellite DMB network; ; (b) searching for a specific control information field used to recognize the WiBro network in a pilot signal included in the satellite DMB signal; And (c) recognizing the WiBro network by analyzing an identifier included in the specific control information field.

According to the present invention, the WiBro service area established in the DMB service area is recognized, and thus, a desired service can be selected and used from the DMB service and the WiBro service.

WiBro, Mobile Internet, Satellite, DMB, MM-MB Terminal

Description

Method and System for Recognizing WiBro Network in Satellite DMB Network {Method and System for Acknowledging WiBro Network in Coverage of Satellite DMB Network}

1 is a schematic view showing a WiBro system;

2 is a diagram illustrating a frame structure of a pilot signal transmitted in a satellite DMB network;

3 is a view showing the configuration of a satellite DMB system according to an embodiment of the present invention;

4 is a flowchart illustrating a method for recognizing a WiBro network in a satellite DMB network according to an exemplary embodiment of the present invention.

 <Explanation of symbols for the main parts of the drawings>

300: satellite DMB system 310: satellite DMB broadcasting center

320: DMB transmitter 330: DMB satellite

340: gap filler 350: mobile communication terminal

360: DMB Service Area 370: WiBro Service Area

The present invention relates to a method and system for recognizing a WiBro network in a satellite DMB network. More specifically, the WiBro network is recognized by searching for specific control information used to recognize the WiBro network from the pilot signal included in the satellite DMB signal transmitted from the satellite DMB network, and analyzing the identifier included in the specific control information field. The present invention relates to a method and system for recognizing a WiBro network in a satellite DMB network.

As computer, electronic, and communication technologies have made rapid progress, various wireless communication services using wireless networks have been provided. Accordingly, a service provided by a mobile communication system using a wireless communication network is developing not only a voice service but also a multimedia communication service for transmitting data such as circuit data, packet data, and the like. In recent years, the third generation mobile communication system IMT-2000 (International Mobile Telecommunication 2000) (eg, CDMA 2000 Codex Multiple Access 2000 1X, 3X, EV-DO, Wideband CDMA (WCDMA, etc.)) has been commercialized. .

However, the existing mobile communication system has a limitation in providing the high-speed wireless Internet because the base station construction cost is high, the usage fee of the wireless Internet is high, and the screen size of the mobile communication terminal is limited. Therefore, WiBro (Wireless Broadband Internet), a high-speed portable Internet service that guarantees portability and mobility and can use high-speed wireless Internet service at a low price, has emerged.

WiBro service uses various types of portable mobile terminals such as laptops, PDAs, and handheld PCs to access various information and contents through internet access in indoor and outdoor stationary environments and mobile environments with walking speeds and low to medium speeds. It is a service. WiBro system uses the 2.3 GHz frequency band and provides mobility of 60 km / h per hour. The downlink transmission rate is 24.8 Mbps, but the uplink transmission rate is 5.2 Mbps. System. In addition, the WiBro system uses a time division duplex (TDD) in a duplex method and an orthogonal frequency division multiple access (OFDMA) / time division in a multiple access (TDMA) method in order to effectively use an allocated frequency spectrum. Multiple Access).

1 is a configuration diagram schematically showing a WiBro system.

As shown in FIG. 1, the WiBro system includes a personal subscriber station (PSS) 100, a radio access station (RAS) 110, an access control router (ACR) 120, and a packet data serving node (PDSN) 130. ), A Home Agent (HA) 140, an AAA (Authentication, Authorization, Accounting) 150, an IP network 160, the Internet 170, and the like.

The PSS 100 refers to a mobile communication terminal that uses a high-speed wireless Internet service by accessing a WiBro system, and has a low power RF (RF) / IF (Intermediate Frequency) module and controller function, service characteristics, and MAC (Media Access) according to a radio wave environment. Control) It has frame variable control function, handover function, authentication and encryption function.                         

The RAS 110 transmits data received from the ACR 120 to the PSS 100 wirelessly as a base station of the WiBro system, and provides a low power RF / IF module and controller function, OFDM / TDD packet scheduling and channel multiplexing function, and service. MAC frame variable control, 50 Mbps high-speed traffic real-time control, handover function, etc. according to characteristics and propagation environment.

In addition, the PSS 100 and the RAS 110 have a 50 Mbps packet transmission modulation and demodulation function, a high speed packet channel coding function, a real time modem control function, and the like for data transmission.

The ACR 120 is a packet access router accommodating a plurality of RAS 110, and has a handover control function between the RAS 110, a handover function between the ACR 120, a packet routing function, an Internet access function, and the like. Is connected to.

The PDSN 130 relays transmission and reception of packet data between an external packet data service server such as the Internet 170 and a base station through the IP network 160, and manages location information data of a mobile communication terminal including the PSS 100. do.

The HA 140 performs routing for tracking and connecting to a location of an external packet data service server such as the Internet 170, and the AAA 150 works with the PDSN 130 for the packet used by the PSS 100. Charge the data and authenticate the connection from the PSS 100.

The IP network 160 connects the PDSN 130, the HA 140, and the AAA 150, and receives packet data from an external packet data service such as the Internet 170 and transmits the packet data to the AP 110.                         

On the other hand, with the development of mobile communication technology, the demand for using a broadcast service including a video service and a voice service in a mobile communication environment has increased rapidly, and digital multimedia broadcasting (DMB: Digital Multimedia Broadcasting, hereinafter referred to as 'DMB'). This has risen.

Digital multimedia broadcasting refers to a broadcasting service that digitally modulates various multimedia data such as image data and audio data and provides the same to a fixed terminal or a portable terminal. In other words, it means a service that can provide high-quality, high-definition broadcasting of CD (Compact Disc) or DVD (Digital Versatile Disc) level to a mobile communication terminal or a vehicle terminal such as a mobile phone, a PDA (Personal Digital Assistant) even while on the move. Unlike conventional analog broadcasting, the DMB broadcasting service is combined with a mobile communication network and provides an interactive service such as remote purchase, telemedicine, or distance education. For example, you can order advertising products that are broadcast on the go, and you can also download your favorite educational programs.

As such, with the emergence of various services using mobile communication technology, mobile communication service companies can simultaneously service multiple multi-systems such as CDMA-2000, EV-DO, WCDMA, WiBro, and DMB.

Accordingly, in order to use various kinds of services provided by a mobile communication service company, a multimode multiband (MM-MB), which can support multiple mobile communication systems, is referred to as MM-MB. need. Here, the multi mode may include a synchronous mode, an asynchronous mode, a WiBro mode, a DMB mode, and the like, and the multiband refers to a frequency band used according to an operation mode of the MM-MB terminal. The mobile communication subscriber can use the mobile communication service by selecting an operation mode according to the type of communication service provided in the region where the subscriber is located by using the MM-MB terminal.

The existing CDMA-2000, EV-DO, etc. can recognize the service area of the other network so that one of the CDMA-2000 service and the EV-DO service can be selected and used by using the MM-MB terminal. Is presented.

However, when the MM-MB terminal is located in an area in which the DMB network and the WiBro network are overlaid, a method for recognizing the WiBro network in the DMB network has not been proposed yet.

In order to solve the above problems, the present invention is to search for specific control information used to recognize the WiBro network from the pilot signal included in the satellite DMB signal transmitted from the satellite DMB network, and to identify the identifier included in the specific control information field The purpose of the present invention is to provide a method and system for analyzing WiBro networks.

It is also an object of the present invention to provide a mobile communication terminal that recognizes a WiBro network in a satellite DMB network and selects a desired service from a DMB service and a WiBro service.

According to a first object of the present invention, a WiBro network can be used to use a WiBro service in an area in which a satellite DMB network providing digital multimedia broadcasting (DMB) service is provided. A method for recognizing a signal, the method comprising: (a) receiving a satellite DMB signal transmitted from the satellite DMB network; (b) searching for a specific control information field used to recognize the WiBro network in a pilot signal included in the satellite DMB signal; And (c) recognizing the WiBro network by analyzing an identifier included in the specific control information field.

According to a second object of the present invention, a MM-MB terminal capable of using the DMB service and the WiBro service by recognizing a WiBro network in an area where a satellite DMB network providing a DMB service is provided, and transmitting the DMB service in the satellite DMB network Receives a satellite DMB signal, retrieves specific control information used to recognize the WiBro network from the pilot signal included in the satellite DMB signal, and analyzes the identifier included in the field of the specific control information to the WiBro network It provides a mobile communication terminal characterized in that the recognition.

According to a third object of the present invention, in a system for recognizing a WiBro network so that a WiBro service can be used in an area in which a satellite DMB network providing a DMB service is constructed, a satellite DMB is transmitted through a DMB transmitter. A broadcasting center; A DMB satellite receiving and relaying the satellite DMB signal transmitted from the satellite DMB broadcasting center; A gap filler relaying the satellite DMB signal received from the DMB satellite to a radio wave shadow area; And receiving the satellite DMB signal from the DMB satellite or the gap filler, searching for specific control information used for recognizing the WiBro network from a pilot signal included in the satellite DMB signal, and searching for a field of the specific control information. It provides a system for recognizing a WiBro network in a satellite DMB network, characterized in that it comprises a mobile terminal for recognizing the WiBro network by analyzing the included identifier.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. First of all, in adding reference numerals to the components of each drawing, it should be noted that the same reference numerals are used as much as possible even if displayed on different drawings. In the following description of the present invention, a detailed description of known functions and configurations incorporated herein will be omitted when it may make the subject matter of the present invention rather unclear.

2 is a diagram illustrating a frame structure of a pilot signal transmitted in a satellite DMB network.

The DMB satellite transmits a Code Division Multiple (CDM) signal to the ground, and receives a CDM signal from a terminal to use the DMB service. The CDM signal is composed of 32 channels from CH 0 to CH 31, and CH 0 transmits a pilot signal as a pilot channel.

As shown in FIG. 2, the pilot signal transmitted through CH 0 is configured in a super frame unit having a length of 76.5 ms, and the super frame is composed of six frames having a length of 12.75 ms. Each frame has a configuration in which 51 pilot symbols (PS) and 51 control information (D1 to D51) are alternately arranged. Each pilot symbol and control information consists of 32 bits, and the basic unit consisting of the pilot signal and the control information has a length of 250 μs.

Here, D1 may be used as a unique word and D2 may be used as a frame counter, and D51 may be used to distinguish a gap filler ID to be described later. That is, the remaining 48 control information (D3 to D50) except for D1, D2, and D51 are not yet defined for a specific purpose.

Accordingly, a specific control information field may be selected from the control information fields D3 to D50, and a specific bit may be designated in the selected specific control information field to be used as an identifier for recognizing the WiBro network in the DMB network.

Of course, the control information field is not limited to the purpose of recognizing the WiBro network, and specific control information for recognizing the existing IS-95 network, CDMA-2000 network, EV-DO network, and WCDMA network in the satellite DMB network. A specific bit of the field may be specified and used as a network identifier.

For example, in order to recognize a WiBro network in a DMB network, one bit of Most Significant Bit (MSB) of D4 may be used as an identifier. In this case, D4 is designated as "00000000 ..... 00000000" in the area where only DMB service is available, and D4 is designated as "10000000 ..... 00000000" in the area where DMB service and WiBro are available. WiBro networks can be recognized by local DMB networks.                     

In addition, the number of bits of the identifier may be adjusted and used as an identifier so that the DMB network can recognize other networks other than the WiBro network. In order to recognize the IS-95, CDMA-2000, EV-DO, WCDMA and WiBro networks in the DMB network, one bit may be allocated to identify each network and used as an identifier. .

3 is a diagram showing the configuration of a satellite DMB system according to a preferred embodiment of the present invention.

As shown in FIG. 3, the satellite DMB system 300 according to the preferred embodiment of the present invention includes a satellite DMB broadcasting center 310, a DMB transmitter 320, a DMB satellite 330, and a gap filler ( 340, a mobile communication terminal 350, and the like.

On the other hand, since the satellite DMB service system 300 transmits DMB service data through the DMB satellite body 330, coverage of the DMB service area 360 is very wide, thereby enabling nationwide network service. On the other hand, since the WiBro network will be built from some regions as commercialization progresses, the WiBro service area 370 will be located in the DMB service area 360. Therefore, when the mobile communication terminal 350 moves to the WiBro service area 370, the present invention recognizes the WiBro network in the satellite DMB network so as to select and use a desired service from the DMB service and the WiBro service.

The satellite DMB broadcasting center 310 receives a broadcast content from a broadcast program provider (PP: Program Provider), compresses and modulates it into a digital signal, and then uses the Ku-Band band using a frequency of 13 to 14 GHz, and the DMB satellite body 330. It transmits to the network. For convenience of explanation in the following process, the digital signal transmitted in the Ku-Band band from the satellite DMB broadcasting center 310 is defined as a satellite DMB signal.

The satellite DMB signal transmitted from the satellite DMB broadcasting center 310 is transmitted from the DMB transmitter 320 to the DMB satellite 330 through an air interface. The air interface over which satellite DMB signals are transmitted consists of a video channel, an audio channel and a data channel. As described above in FIG. 2, since CH 0 is a pilot channel, the remaining channels are divided and used as a video channel, an audio channel, and a data channel. Video data and audio data of broadcast content are transmitted through an audio channel and a video channel, respectively, and the data channel may be used as a channel for various data services including broadcast information data.

The DMB satellite 330 is seated on a stationary orbit about 36,000 km from the ground, and rotates at a speed of 11,000 km per hour, which is the same as the rotation speed of the earth. The DMB satellite 330 receives a satellite DMB signal transmitted from the DMB transmitter 320 and transmits the received satellite DMB signal to the mobile communication terminal 350 or the gap filler 340.

In general, the DMB satellite 330 includes four 25 MHz Ku-Band repeaters and 36 25 MHz S-Band repeaters that provide a frequency band required for transmitting satellite DMB signals to the mobile communication system. The DMB satellite 330 simultaneously transmits an S-Band CDM signal using a frequency of about 2.6 GHz and a Ku-Band TDM (TDM) signal using a frequency of 11 to 12 GHz. The CDM signal of the S-Band band is transmitted to the mobile communication terminal 350, and the TDM signal of the Ku-Band band is transmitted to the gap filler 340.

The gap filler 340 is a shaded area repeater installed in an underground space, a building, a dense residential area, etc., which are difficult to receive radio waves, and relay satellite DMB signals. The gap filler 340 receives the TDM signal in the Ku-Band band from the DMB satellite 330, converts the TDM signal in the S-Band band, and transmits the converted CDM signal to the mobile communication terminal 350.

The mobile communication terminal 350 is an MM-MB terminal capable of using both a DMB service and a WiBro service. In order to use the DMB service, the mobile communication terminal 350 may include a DMB antenna for receiving a satellite DMB signal, a DMB tuner for selecting a desired channel signal among the satellite DMB signals, and a signal received from the DMB tuner in accordance with a broadcast MPEG standard. MPEG decoding unit for decoding, video data or audio data decoded in the MPEG decoding unit may include an A / V switch unit for separating the video output and audio output A / V (Audio / Video) signal capable of audio and the like.

In addition, the mobile communication terminal 350 may use a WiBro service, such as a WiBro RF module that extracts a WiBro signal from an RF signal received through an RF antenna, a WiBro modem performing a call processing according to a protocol defined in the WiBRO standard. It may include.

The mobile communication terminal 350 receives a pilot signal of a pilot channel included in the satellite DMB signal and checks an identifier of a specific control information field which is preset to be used for recognizing a WiBro network in a frame of the pilot signal. When the mobile communication terminal 350 is located in the WiBro service area 370, the WiBro network may be recognized by checking the identifier of the control information field. When the mobile communication terminal 350 recognizes the WiBro network in the DMB service area 360, the mobile communication terminal 350 selects and uses a desired service from the DMB service and the WiBro service.

The mobile communication terminal 350 is a terminal equipped with a MM-MB function that can use both a DMB service and a WiBro service. A personal digital assistant (PDA), a hand-held PC, a cellular phone, and a mobile broadband are provided. System) phones and the like.

4 is a flowchart illustrating a method for recognizing a WiBro network in a satellite DMB network according to an exemplary embodiment of the present invention.

As shown in FIG. 4, the DMB satellite 330 receives a satellite DMB signal from the satellite DMB broadcasting center 310 and transmits the signal to a DMB service area, and the mobile communication terminal 350 receives the satellite DMB from the DMB satellite 330. The signal is received or the satellite DMB signal relayed from the gap filler 340 (S400). When the satellite DMB signal is received, specific control information of the pilot signal included in the satellite DMB signal is searched for (S402). In this case, the specific control information is used to select and use the control information to be used as the specific control information from the control information (D3 ~ D50) of the pilot signal frame to be used to recognize the WiBro network.

When searching for specific control information, an identifier included in the specific control information field is analyzed to determine whether a WiBro network exists (S404). The mobile communication terminal 350 determines whether the WiBro network is recognized according to the value of the identifier. For example, if a specific bit included in the specific control information field is used as the identifier, and the value of the identifier is "0", the WiBro network is established. If it is determined that the area is not and the value of the identifier is "1", it can be recognized that the WiBro network exists (S406).

When the WiBro network is recognized in step S406, since the mobile communication terminal 350 is located in an overlay area where both the DMB service and the WiBro service can be used, a desired service can be selected and used from the DMB service and the WiBro service as needed. (S408). On the other hand, if the WiBro network is not recognized in step S408 is because the mobile communication terminal 350 is located in an area where only the DMB service can use the DMB service.

The foregoing description is merely illustrative of the technical idea of the present invention, and various changes and modifications may be made by those skilled in the art without departing from the essential characteristics of the present invention. Therefore, the embodiments disclosed in the present invention are not intended to limit the technical idea of the present invention but to describe the present invention, and the scope of the technical idea of the present invention is not limited by these embodiments. The protection scope of the present invention should be interpreted by the following claims, and all technical ideas within the equivalent scope should be interpreted as being included in the scope of the present invention.

As described above, according to the present invention, the satellite DMB network has the effect of recognizing the WiBro service area built in the DMB service area and selecting a desired service from the DMB service and the WiBro service.

In addition, it is possible to recognize the WiBro network in the DMB network, there is an effect that can provide a variety of mobile communication services in conjunction with the DMB network and the WiBro network.

Claims (25)

In a method of recognizing a WiBro network so that a WiBro service can be used in an area in which a satellite DMB network providing a digital multimedia broadcasting (DMB) service is provided. (a) receiving a satellite DMB signal transmitted from the satellite DMB network; (b) searching for specific control information used for recognizing the WiBro network in a pilot signal included in the satellite DMB signal; And (c) recognizing the WiBro network by analyzing an identifier included in a field of the specific control information Method for recognizing a WiBro network in a satellite DMB network comprising a. The method of claim 1, The method, (d) selecting and using one service among the DMB service and the WiBro service A method for recognizing a WiBro network in a satellite DMB network, characterized in that it further comprises. The method of claim 1, And a pilot symbol (PS) and control information are arranged alternately in a frame of the pilot signal. The method of claim 3, wherein And a frame of the pilot signal comprises 51 pilot symbols and the control information (D1 to D51), respectively. The method of claim 4, wherein And the specific control information is determined by designating control information to be used as the specific control information from the remaining control information (D3 to D50) except for D1, D2, and D51. The method of claim 5, The identifier is a method for recognizing a WiBro network in a satellite DMB network, characterized in that for designating a specific bit in the field of the specific control information. The method of claim 6, If the value of the identifier is "0", the WiBro network is determined as an area where the WiBro network is not established; and if the value of the identifier is "1", the WiBro network is recognized. . The method of claim 4, wherein The D51 is a method for recognizing a WiBro network in a satellite DMB network, characterized in that used to distinguish a gap filler (Gap Filler) ID. MM-MB (Multimode) that can use the DMB service and the WiBro service by recognizing the WiBro network in an area where a satellite DMB network providing digital multimedia broadcasting (DMB) service is provided. Multiband) terminal, Receives a satellite DMB signal transmitted from the satellite DMB network, retrieves specific control information used to recognize the WiBro network from a pilot signal included in the satellite DMB signal, and includes an identifier included in a field of the specific control information. The mobile communication terminal, characterized in that for recognizing the WiBro network. The method of claim 9, The mobile terminal, A DMB antenna for receiving the satellite DMB signal; A DMB tuner for selecting a signal of a specific channel among the satellite DMB signals; An MPEG decoder which decodes the signal received from the DMB tuner in accordance with a broadcast MPEG standard; And A / V switch unit for separating the data decoded by the MPEG decoder into an A / V (Audio / Video) signal Mobile communication terminal comprising a. The method of claim 9, The mobile communication terminal, A WiBro RF module for extracting a WiBro signal from an RF signal received through an RF antenna; And WiBro modem performs call processing according to the protocol defined in the WiBRO specification Mobile communication terminal comprising a. The method of claim 9, And a pilot symbol (PS) and control information are arranged alternately in the frame of the pilot signal. 13. The method of claim 12, The frame of the pilot signal is characterized in that each of the 51 pilot symbols and the control information (D1 ~ D51). The method of claim 13, The specific control information is determined by specifying the control information to be used as the specific control information from the remaining control information (D3 ~ D50) except for D1, D2 and D51. The method of claim 14, And the identifier is used by designating a specific bit in the field of the specific control information. The method of claim 15, And determining that the WiBro network is not established when the value of the identifier is "0", and recognizing the WiBro network when the value of the identifier is "1". The method of claim 13, The D51 is used to distinguish a gap filler (Gap Filler) ID. The method of claim 9, The mobile communication terminal comprises at least one of a personal digital assistant (PDA), a hand-held PC, a cellular phone, and a mobile broadband system (MBS) phone. In a system for recognizing a WiBro network so that a WiBro service can be used in an area where a satellite DMB network providing a digital multimedia broadcasting (DMB) service is provided. A satellite DMB broadcasting center for transmitting satellite DMB signals through a DMB transmitter; A DMB satellite receiving and relaying the satellite DMB signal transmitted from the satellite DMB broadcasting center; A gap filler relaying the satellite DMB signal received from the DMB satellite to a radio wave shadow area; And Receives the satellite DMB signal from the DMB satellite body or the gap filler, searches for specific control information used to recognize the WiBro network from the pilot signal included in the satellite DMB signal, and includes it in the field of the specific control information. The mobile communication terminal to recognize the WiBro network by analyzing the identifier A system for recognizing a WiBro network in a satellite DMB network comprising a. The method of claim 19, And a pilot symbol (PS) and control information are arranged alternately in a frame of the pilot signal, and the WiBro network is recognized in the satellite DMB network. The method of claim 20, And a frame of the pilot signal includes 51 pilot symbols and control information (D1 to D51), respectively. The method of claim 21, And the specific control information is determined by designating control information to be used as the specific control information among remaining control information (D3 to D50) except for D1, D2, and D51. The method of claim 22, And the identifier is used by designating a specific bit in the field of the specific control information. The method of claim 23, wherein When the value of the identifier is "0", the system determines that the WiBro network is not established, and if the value of the identifier is "1", the system recognizes the WiBro network in the satellite DMB network. . The method of claim 21, The D51 is a system for recognizing a WiBro network in a satellite DMB network, characterized in that used to distinguish the ID of the gap filler.

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