KR101366278B1 - Broadcasting receiver and method of processing a broadcasting data - Google Patents

Abstract

A broadcasting receiver and a method of processing broadcasting data are provided to modify an interface between a host and a card a little bit, thereby effectively processing broadcasting data received through an internet network. A signal of a cable broadcasting channel is received(S1200). Received data is transformed to an IMP packet(S1210). The IMP packet is transmitted to a cable card(S1220). Descrambling of data included in a payload of the received packet is performed(S1230). The IMP packet including the descrambled data is again transmitted to a host(S1240). The data included in the payload of the IMP packet is decoded(S1250).

Description

Broadcast receiver and method of processing a broadcasting data}

The present invention relates to a broadcast receiver and a broadcast data processing method, and more particularly, to a broadcast receiver and a broadcast data processing method of a broadcast transmitted using an internet network.

Conventional broadcast receivers are serviced in such a manner that content produced by a broadcaster is transmitted through a radio wave transmission medium such as terrestrial, cable, or satellite broadcasting, and a user views the receiver through a receiver capable of receiving the respective delivery media. .

However, as digital-based digital broadcasting technology has been developed and commercialized in existing analog broadcasting, real-time broadcasting, contents on demand, games, and news using Internet networks connected to homes in addition to existing radio waves or wired cable media. It is now possible to provide a variety of content services to the user.

An example of content service provision using the Internet network is IPTV (Internet Protocol TV). The IPTV refers to the transmission of various information service contents, video contents, and broadcasting contents through an internet network, and providing the same to a receiver of a user. The Internet network can be implemented on various types of networks such as an optical fiber network, a coaxial cable network, a fiber to the home (FTTH), a telephone network, and a wireless network based on IP (Internet Protocol).

In the case of the service using the Internet network as described above, unlike general terrestrial broadcasting, the interactivity may be added, and the user may watch the content service that he / she wants to see at a convenient time. In addition, it is possible to protect the transmission content using limited reception and content protection technology.

However, in the case of protecting content by using the above limited reception, a receiver capable of processing the content data received through the Internet network was required.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a broadcast receiver and a broadcast data processing method for processing data received through an Internet network.

In accordance with another aspect of the present invention, a method of processing broadcast data includes receiving and demodulating a signal of a cable broadcast channel, assigning identification information corresponding to the demodulated data, and demodulating a preheader including a dummy header and the identification information. Broadcast data processing method comprising forming an IP MPEG packet in addition to the data.

In another aspect, a broadcast data processing method according to the present invention includes receiving and demodulating a signal of a cable broadcast channel, assigning identification information corresponding to the demodulated data, and receiving data received through an IP network channel as a corresponding destination. Routing to the network, assigning identification information corresponding to the routed data, and when the demodulated data is received, add a dummy header and a preheader including identification information of the demodulated data to form an IP MPEG packet. And when the routed data is received, adding an preheader including identification information corresponding to the data to form an IP MPEG packet.

In another aspect, a data processing method according to the present invention includes: receiving IP MPEG packet data from a host, descrambling data included in a payload of the received packet, and IP including the descrambled data Transmitting the MPEG packet data to a host.

In another aspect, the data processing method according to the present invention, when the cable broadcast channel data is received to form a cable card MPEG packet using the identification information corresponding to the data, if the IP network channel data is received identification corresponding to the data Forming an IP MPEG packet using information, multiplexing the formed packet to a cable card, receiving a packet including descrambled data from the cable card, and identifying the received packet Demultiplexing.

In another aspect, the data processing method according to the present invention comprises the steps of: receiving multiplexed packet data from a host; identifying a cable card MPEG packet and an IP MPEG packet by distinguishing a payload start position of the received packet; Descrambling data included in the payload of the decompressed packet, and transmitting the packet data including the descrambled data to the host.

In another aspect, the data processing method according to the present invention forms a cable card MPEG packet using identification information and packet identification information corresponding to the data when cable broadcasting channel data is received, and receives the data when IP network channel data is received. Forming an IP MPEG packet using identification information corresponding to the packet identification information and packet identification information; multiplexing the formed packet to a cable card; receiving a packet including descrambled data from the cable card; And identifying and demultiplexing the received packet.

In another aspect, a data processing method according to the present invention includes: receiving multiplexed packet data from a host, identifying cable card MPEG packets and IP MPEG packets using packet identification information included in the received packets; Respectively descrambling data included in the payload of the identified packet, and transmitting packet data including the descrambled data to a host.

In another aspect, the data processing method according to the present invention, when the cable broadcast channel data is received to form a cable card MPEG packet using the identification information corresponding to the data, if the IP network channel data is received identification corresponding to the data Forming an IP MPEG packet using information; multiplexing the formed packet and transmitting the packet to a packet cable card together with a packet start signal and a packet end signal; and packetizing a packet including data descrambled from the cable card Receiving with a start signal, a packet end signal, and identifying and demultiplexing the received packet.

According to another aspect of the present invention, a data processing method includes receiving multiplexed packet data from a host together with a packet start signal and a packet end signal, using a packet start signal and a packet end signal received together with the packet. Identifying an MPEG packet and an IP MPEG packet, descrambling data included in a payload of the identified packet, respectively, and packet data including the descrambled data together with a packet start signal and a packet end signal. Transmitting to the host.

In accordance with another aspect of the present invention, a broadcast receiver includes a tuner configured to tune a frequency to receive a signal of a cable broadcast channel, a demodulator to demodulate the tuned signal, a network interface to receive data transmitted through an IP network channel, and the received A network stacker configured to route data to a corresponding destination, and a preheader including a dummy header and identification information corresponding to the demodulated data is added to the data received from the demodulator to form an IP MPEG packet, and the network And a pre-header including the identification information corresponding to the data to the data received from the stack to form an IP MPEG packet, and multiplexing the multiplexed IP MPEG packet and transmitting the same to the cable card.

In another aspect, a broadcast receiver includes a tuner for tuning a frequency to receive a signal of a cable broadcast channel, a demodulator for demodulating the tuned signal, a network interface unit for receiving data transmitted through an IP network channel, A network stack unit for routing the received data to a corresponding destination, a preheader including identification information corresponding to the demodulated data is added to the data received from the demodulator to form a cable card MPEG packet, and the network A multiplexer for forming an IP MPEG packet by adding a preheader including identification information corresponding to the data to data received from the stack, multiplexing the multiplexed packets to be transmitted to the cable card, and descrambled data. Cable card MPEG packet or IP MPEG packet to include from cable card And, discriminates the type of the received packet in accordance with the payload start location of the packet, including a demultiplexing unit for demultiplexing.

In another aspect, a broadcast receiver includes a tuner for tuning a frequency to receive a signal of a cable broadcast channel, a demodulator for demodulating the tuned signal, a network interface unit for receiving data transmitted through an IP network channel, A network stack unit for routing the received data to a corresponding destination, and a preheader including identification information and packet identification information corresponding to the demodulated data, to the data received from the demodulation unit, to add a cable card MPEG packet. And a preheader including identification information and packet identification information corresponding to the data to data received from the network stack unit to form an IP MPEG packet, and multiplexing each of the formed packets to transmit to a cable card. It includes a multiplexer.

In another aspect, a broadcast receiver includes a tuner for tuning a frequency to receive a signal of a cable broadcast channel, a demodulator for demodulating the tuned signal, a network interface unit for receiving data transmitted through an IP network channel, A network stack unit for routing the received data to a corresponding destination, a preheader including identification information corresponding to the demodulated data is added to the data received from the demodulator to form a cable card MPEG packet, and the network A multiplexer for forming an IP MPEG packet by adding a preheader including identification information corresponding to the data to data received from the stack, multiplexing the multiplexed packets to be transmitted to the cable card, and a packet start signal and a packet. To send the multiplexed packet to the cable card with a termination signal. And a controller.

According to the data processing method and the broadcast receiver of the present invention, there is an effect that can efficiently exchange information by using an interface between the host and the card of the receiver.

The in-band data received through the Internet network can be transmitted to the card using a separate data structure, and it can be easily extended to other types of in-band data. If the same data structure is used for the data received through the Internet network and the cable broadcast data, there is an effect that the interface between the host and the card can be simplified.

In addition, according to the present invention, it is possible to effectively process broadcast data received through the Internet network with little modification of the interface between the host and the card.

BRIEF DESCRIPTION OF THE DRAWINGS The objects, features and advantages of the present invention will become apparent from the following detailed description of embodiments with reference to the accompanying drawings. In addition, although the term used in the present invention is selected as a general term that is widely used at present, in some cases, there is a term arbitrarily selected by the applicant. In this case, the meaning is described in detail in the description of the present invention. It is to be understood that the present invention should be grasped as a meaning of a term other than a name.

Operation of the broadcast data processing method and the broadcast receiver according to the present invention configured as described above will be described in detail with reference to the accompanying drawings.

An Internet Protocol TV (IPTV) system, which is an example of a system that can provide various contents using the Internet network, can be largely divided into a server, a network, and a receiver.

The servers of the IPTV are servers that perform various functions such as service discovery and selection server, streaming server, contents guide information server, customer information server, and payment information server. It can be configured as.

Among the servers, the streaming server transmits the stored Moving Picture Experts Group (MPEG) 2 or MPEG4 encoded video data to the user through a network. As a protocol for the transmission, a Real-Time Transport Protocol (RTP), a RTP Control Protocol (RTP), or the like may be used.

In case of using Real-Time Streaming Protocol (RTSP), video stream playback can be controlled to some extent through a function called network trick play such as pause, replay, and stop. .

The content guide information server is a server that provides information on the various contents provided. The content guide information is information corresponding to electronic program guide (EPG) information and includes various information about content. The content guide information server stores content guide information data, and provides the stored data to the receiver.

The information server related to service discovery and selection among the servers provides the receiver with access information and playback information for servers providing various content services such as broadcasting, contents on demand (COD), and games.

The network system consists of an internet based network and gateways. The Internet-based network may use various types of networks such as an optical cable network, a coaxial cable network, a fiber to the home (FTTH), a telephone network, a wireless network, and the like based on IP. In addition to general data transfer, the gateway may perform multicast group management and quality of service (QoS) management using protocols such as Internet Group Management Protocol (IGMP).

A receiver of an IPTV refers to a receiver capable of receiving data transmitted through an internet network and providing the same to a user. The receiver includes an IPTV settop, a homenet gateway, an IPTV embedded TV, and the like.

In the case of a hybrid IPTV system, various types of contents of the Internet as well as various types of existing broadcasting contents may be provided. That is, the user can provide various broadcasting contents such as terrestrial broadcasting, cable broadcasting, satellite broadcasting, personal broadcasting, various internet video contents, data contents other than video, and the like. The contents may be provided in real time or may be provided on demand.

1 is a diagram schematically showing an IPTV system according to an embodiment of the present invention. In terms of providing a content service, the IPTV system may be divided into a content provider (CP), a service provider (SP), a network provider (NP), and a user.

The content provider produces and provides various contents. As shown in FIG. 1, the content provider includes a terrestrial broadcaster, a cable SO, or a MSO, a satellite broadcaster, and an internet broadcaster. (Internet broadcaster) and the like.

The service provider provides a service package of contents provided by the content provider. For example, the service provider of FIG. 1 packages a first terrestrial broadcast, a second terrestrial broadcast, a cable MSO, satellite broadcast, various Internet broadcasts, and provides the same to a user.

The network provider provides a network for providing the service to a user. The user may build a home network end user (HNED) to receive the service.

Conditional access, content protection, or the like may be used as a means for protecting content transmitted from the IPTV system. As one example for the above-mentioned restriction reception or content protection, a method such as a cable card or a downloadable conditional access system (DCAS) may be used.

The use of the cable card or DCAS is a choice of a service provider that provides an IPTV service. When the cable card or DCAS is used in a receiver, the system may be used by a service provider or a headend that transmits and receives data with the receiver. Should be used. For example, if a cable SO or MSO also provides an IP-based service using a cable, the cable SO or MSO may be a service provider. In this case, the limited reception system should be used for the cable SO or MSO as well as the receiver.

2 is a schematic diagram of a receiver using a cable card according to an embodiment of the present invention. The receiver of FIG. 2 represents a receiver capable of receiving all IP-based IPTV services, cable broadcasts, terrestrial broadcasts, satellite broadcasts, and the like. The receiver of FIG. 2 may be implemented as a case in which only an IPTV service is received or only a cable broadcast is received, in which case the remaining services except for one can be received. And the cable card of Figure 2 may be called a different name according to the embodiment as described above, the idea of the invention is not limited by the name. For example, when used for an IPTV service, it may be called an IP card.

The receiver of FIG. 2 is mainly composed of a host and a cable card. The host includes a first tuner 202, a second tuner 204, a demodulator 206, a multiplexer 208, a demultiplexer 210, and a decoder. ) 212, NIC (Network Interface Card) unit 214, network stack (network stack) unit 216, control unit 218, DCAS (Downloadable CAS) unit 222, DVR (Digital Video Recorder) control unit ( 224, a content encryption unit 226, a storage interface unit 228, and a storage unit 230.

The receiver uses an open cable method in which a cable card including a conditional access (CA) system is separated from the main body. The cable card is also referred to as a POD (Point Of Deployment) module, and can be inserted into and removed from the main body slot of the receiver. The main body into which the cable card is inserted is also referred to as a host. That is, the cable card and the host are collectively called a receiver.

The host of FIG. 2 is a multi-stream host that processes a plurality of streams, and in the case of a single stream host that processes one stream, the multiplexer 208 of the host of FIG. And the demultiplexer 210 is not used. The cable card 220 may use a single stream card that can process only one stream, or a multi-stream card that can process multiple streams simultaneously.

The network connection unit 200 connects the external network and the receiver. For example, the network connection unit 200 may connect an external IP network network and the receiver. For example, when using MoCA (Multimedia Over Coax Alliance), an IP-based network can be established and connected over a coaxial cable network. Alternatively, it may be connected to an external network using a DOCSIS modem, or may be connected to an external network using a wireless repeater that connects to a wireless internet network, or a wired repeater that connects to a wired internet network such as a wired ADSL repeater. . The connection example with the external network is an embodiment, and which one to use may vary depending on how it is connected to the external network.

The first tuner 202 is a demodulator by tuning a frequency for a specific channel of terrestrial A / V (Audio / Video) broadcast transmitted through an antenna or a cable broadcast received through a cable connected to the network connection unit 200. Output to (206).

In this case, since the terrestrial broadcast and the cable broadcast have different transmission methods, the demodulation method in the demodulator 206 is also different. For example, terrestrial A / V broadcasting is modulated and transmitted in VSB (Vestigial Sideband Modulation), and cable broadcasting is modulated and transmitted in QAM (Quadrature Amplitude Modulation). Therefore, if the channel frequency tuned by the first tuner 202 is a terrestrial broadcast, the demodulator 206 demodulates by the VSB scheme, and if it is a cable broadcast, it is demodulated by the QAM scheme.

The second tuner 204 tunes the frequency of a specific channel in the cable broadcast transmitted in-band through a cable connected to the network connection unit 200 and outputs the tuned frequency to the demodulator 206.

The signals of different channels may be tuned and transmitted to the demodulator 206 using the first tuner 202 and the second tuner 204. Alternatively, different A / V streams of the same channel as the first tuner 202 may be tuned and transmitted to the demodulation unit 206. For example, the first tuner 202 may tune the stream of the main picture, and the second tuner 204 may tune the stream of the picture in picture (PIP). When the digital video signal is stored using a DVR (Digital Video Recorder) or the like, the first tuner 202 and the second tuner 204 are used to watch an image while simultaneously storing another image and the like. record).

The demodulator 206 demodulates the received signal and transmits the demodulated data to the multiplexer 208. For example, an MPEG TS (Transport Stream) stream coded by an MPEG coding scheme such as MPEG 2 or MPEG 4 may be transmitted to the multiplexer 208. Alternatively, a stream coded by another coding scheme may be transmitted. This depends on the coding scheme of the received data. Hereinafter, it is assumed that the MPEG TS stream is received.

In addition, the demodulator 206 assigns a local transport stream ID (LTSID) to the MPEG TS received and demodulated from the first tuner 202 and the second tuner 204, and multiplexes the given LTSID information. Send to section 208. The LTSID is identification information used to identify corresponding stream data. In the above example, the demodulator 206 assigns the LTSID to data received through the cable broadcast channel. However, the multiplexer 208 may assign the LTSID to the data received through the cable broadcast channel.

The NIC unit 214 is a kind of network interface unit. The NIC unit 214 receives an Ethernet frame packet transmitted to a specific IP address among the signals received through the network connection unit 200 and transmits it to the network stack unit 216. The IP address may be an IP address of the host itself or an IP address of the cable card. Alternatively, data according to bidirectional communication (for example, a paid program request, status information of a receiver, a user input, etc.) is received from the network stack 216 and transmitted to the external network through the network connection unit 200.

In the receiver of FIG. 2, out-of-band message data according to an IP protocol, or in-band data including audio, video, data broadcast data, and the like is used to connect the NIC unit 214. Can be received via.

In the case of existing cable broadcasting, system information (SI), emergency alert system (EAS), eXtended Application Information Table (XAIT), and conditional access system information using a DSG (DOCSIS Settop Gateway) or OOB (Out Of Band) method. And OOB data such as various cable card control information.

In the receiver of FIG. 2, a DOCSIS modem, an OOB tuner, or the like may be provided in a host to receive the OOB data. For example, OOB data may be received using one of an IP method and an OOB method, or OOB data may be received using one of an IP method, a DSG method, and an OOB method.

In case of receiving OOB data by selecting one of the IP method and the OOB method, an OOB modem, a demodulator, etc. are further required in the receiver as shown in FIG. In the case of receiving OOB data by selecting one of an IP method, a DSG method, and an OOB method, a switching unit for selecting a DOCSIS modem, an OOB modem, the DSG method and an OOB method in the receiver as shown in FIG. According to each scheme, a demodulator for transmitting data to a head end or a service provider is required. When there are a plurality of schemes as described above, it is determined in the headend or the like which scheme is used and transmitted to the cable card. The cable card transmits the received operation information to the host. In the receiver of FIG. 2, for convenience of description, a path and a block of a DSG method using the DOCSIS modem or an OOB method using an OOB tuner are omitted.

The network stack unit 216 routes each received packet to the destination of the packet. For example, the network stack unit 216 may route a packet to a destination using a network stack based on Transmission Control Protocol (TCP) / Internet Protocol (IP) protocol. The network stack unit 216 may support both a TCP / IP protocol and a User Datagram Protocol (UDP) / IP protocol. In addition, the network stack unit 216 may perform in-band data and OOB data classification, jitter filtering, and the like using packet header information.

3 is a diagram illustrating the structure of an Ethernet frame according to an embodiment of the present invention. The Ethernet stack 216 receives the Ethernet frame having the structure as shown in FIG. 3. The frame includes a 14-byte Ethernet header, a 20-byte IP header, an 8-byte UDP header, a payload, and an Ethernet cyclic redundancy check (CRC). When data is transmitted according to a TCP protocol other than the UDP protocol, a TCP header other than the UDP header may be used, and a TCP payload other than the UDP payload may be included and received. The payload may include in-band data, OOB data, and the like.

The network stack unit 216 classifies and receives the data received in the format shown in FIG. 3 into in-band data and OOB data. In order to distinguish the in-band data and the OOB data, header information or the like by appointment between the transmitting side and the receiving side may be used. The separated in-band data and OOB data may be routed to a data destination using second layer routing or third layer routing, respectively.

When the second layer routing is used, routing is performed using a MAC (Media Access Control) address system of a destination included in an Ethernet header of a received Ethernet frame. In case of using the third layer routing, routing is performed using the destination IP address system included in the IP header of the received Ethernet frame. Whether to use the second layer routing or the third layer routing may vary depending on implementation. That is, a second layer routing scheme may be used or a third layer routing scheme may be used according to an implementation.

For example, when using the second layer routing, the data used in the host among the received data includes MAC address information of the host in the Ethernet header. In case of using the third layer routing, the data used in the host among the received data includes the IP address information of the host in the IP header.

Among the data received by the network stack unit 216, in-band data including audio, video, data broadcast data, and the like is routed to the multiplexer 208. The in-band data may be an MPEG TS stream coded by an MPEG coding scheme such as MPEG 2 or MPEG 4, or a stream coded by other coding schemes.

4 is a diagram illustrating a structure of data routed to the multiplexer 208 according to an embodiment of the present invention. In the example of FIG. 4, the payload includes MPEG-TS coded based on MPEG. As shown in FIG. 4, the network stack unit 216 transmits data other than the Ethernet header and the Ethernet CRC to the multiplexer 208 in the received Ethernet frame. Hereinafter, data having a structure as shown in FIG. 4 will be referred to as an IP packet.

According to an embodiment of the host, an IP packet including A / V data of several channels may be simultaneously received. Accordingly, the multiplexer 208 multiplexes the LTSIDs to data included in IP packets of different channels. For example, when the multiplexer 208 receives the IP packet as shown in FIG. 4, the MPEG-TS is transmitted to each MPEG-TS using predetermined routing index information such as a server or a headend which transmits data. LTSID to be mapped can be given. The routing index information may be obtained from information included in the IP header or the UDP (or TCP) header. The cable card may classify and descramble the data using the LTSID, and the host may correctly route the data using the LTSID.

5 is a diagram illustrating an LTSID table according to an embodiment according to the present invention. By using the table as described above, the IP packet data corresponding to each channel received through the IP network and the in-band data of the cable broadcasting channel can be identified together.

The QAM Cable index is used to identify the A / V data stream received through the Quadrature Amplitude Modulation (QAM) channel of the cable broadcasting channel. For example, when a plurality of cable broadcast channels can be received through a plurality of tuners, the LTSID may be assigned to correspond to each of the tuners. As shown in FIG. 2, in order to identify the A / V data stream received by the first tuner 202, the QAM Cable index 1 (LTSID 1) is used, and the A / V data stream received by the second tuner 204 is used. QAM Cable index 2 (LTSID 2) can be assigned to identify.

The IP index is used to identify IP packet data corresponding to each channel received through the IP network channel. Various methods may be used to assign an LTSID to identify the IP packet data.

First, the LTSID may be assigned by using the IP address information included in the IP header portion of the IP packet received by the multiplexer 208. That is, when there is at least one IP address in the receiver, an LTSID may be assigned for each IP address. Therefore, the received data can be distinguished for each IP address. For example, IP index 1 (LTSID 3) is assigned to IP packets received at the 1.1.1.1 IP address of the receiver, and IP index 2 (LTSID 4) is assigned to IP packets received at the 1.1.1.2 IP address. can do. IPv4, IPv6, and the like may be applied to the IP address system, and the above-mentioned IP address is just an example. However, the information included in the IP header portion of each frame or packet described above may vary according to the IP address system.

Second, the LTSID may be assigned by using the port information included in the UDP (or TCP) header portion of the IP packet received by the multiplexer 208. That is, at least one port may exist in the receiver, and an LTSID may be assigned to each port. Therefore, the received data can be distinguished for each port. For example, IP index 1 (LTSID 3) may be assigned to an IP packet received through port 6 of the receiver, and IP index 2 (LTSID 4) may be assigned to an IP packet received through port 17. The port number mentioned above is just an example.

Third, the LTSID may be assigned by using both the IP address included in the IP header portion of the IP packet received by the multiplexer 208 and the port information included in the UDP (or TCP) header portion. That is, at least one IP address and port may exist in the receiver, and the LTSID may be assigned using the IP address and the port. For example, IP index 1 (LTSID 3) is assigned to IP packets received on port 6 of the IP packets received at the 1.1.1.1 IP address, and number 17 is counted among the IP packets received at the 1.1.1.1 IP address. IP index 2 (LTSID 4) may be assigned to the IP packet received through the port. In addition, IP index 3 (LTSID 5, not shown) may be assigned to IP packets received through port 6 among the IP packets received through the 1.1.1.2 IP address.

In the table, a routing destination (Routing Dest) represents a destination to which the data is routed after demultiplexing in the demultiplexer 210, and a format indicates that the demultiplexed data is routed in the demultiplexer 210. Indicates the data format of the case. For example, data having an LTSID value of 1 is demultiplexed by the demultiplexer 210 and then routed to a decoder, and the data format routed to the decoder is MPEG-TS. Data having an LTSID value of 4 is demultiplexed by the demultiplexer 210 and then routed to a storage unit (HDD, etc.). The routed data format includes an IP header or the like added to MPEG-TS as shown in FIG. It is in the form of an IP packet.

The routing destination information and the format information as described above may be set by the user's setting or the like when the LTSID is assigned. That is, the information may be changed by setting or the like.

The multiplexer 208 may insert an LTSID into data received by the demodulator 206 and the network stack 216, and multiplex and output the received data. For example, the main image tuned and demodulated by the first tuner 202 and the PIP image tuned and demodulated by the second tuner 204 may be multiplexed and output. Alternatively, according to an embodiment, images of other channels may be multiplexed, or may be multiplexed with signals output from the network stack 216. When data coded based on MPEG is received at the receiver, the multiplexer 208 receives MPEG-TS data.

When the cable card of the receiver is an S-CARD supporting a single stream, the host transmits the received data to the cable card as it is. Therefore, the multiplexer 208 or the demultiplexer 210 of FIG. 2 is not used. However, when the cable card is an M-CARD supporting multiple streams, a process of multiplexing and demultiplexing a plurality of stream data into one is required. In the multiplexing step, a 12-byte preheader is added to the stream data to multiplex the data, and the preheader is removed in the demultiplexing step.

The receiver of FIG. 2 is an example in which an M-CARD supporting multiple streams is used. Therefore, when data is received by the multiplexer 208, the multiplexer 208 adds a preheader to the data, multiplexes it, and outputs the data. The preheader includes LTSID information. Data received from the demodulator 206 and the network stack 216 are different in data format. For example, the demodulator 206 may receive data in the form of MPEG-TS, and the data of the IP packet form as shown in FIG. 4 may be received from the network stack 216. The multiplexer 208 divides the received data, adds a preheader, and transmits the preheader.

The multiplexer 208 outputs data that does not require CA descramble, such as terrestrial broadcast data, to the demultiplexer 210, and provides data that requires CA descramble such as cable broadcast data or IPTV in-band data. Output to 220.

The cable card 220 includes a conditional access (CA) system and is also referred to as a POD (Point Of Deployment) module in order to prevent copying and limited access to high value-added broadcast contents. That is, the cable card 220 descrambles the received data and transmits it to the demultiplexer 210 of the host. If the cable card 220 is not mounted, the data output from the multiplexer 208 is directly output to the demultiplexer 210. In this case, the scrambled broadcast data cannot be descrambled and thus cannot be viewed normally.

The demultiplexer 210 demultiplexes and receives the data received from the cable card. The demultiplexed data is processed using the LTSID included in the preheader. For example, data of a packet having a specific LTSID may be transmitted and decoded to the decoder 212, and data of a packet having another LTSID may be stored in the storage unit 230 using a digital video recorder (DVR). . The decoder 212 restores and outputs the compressed A / V signal to the original signal through a video decoding algorithm and an audio decoding algorithm, respectively.

The DVR controller 224, the content encryption unit 226, the storage interface unit 228, and the storage unit 230 serve to store the received digital data or to output and reproduce the stored data. The DVR controller 224 controls to store the selected video data among the data output from the demultiplexer 210 or reproduce the selected video data among the stored data under the control of the controller 218. The content encryption unit 226 encrypts and outputs the data to be stored, or restores and outputs the encrypted and stored data. The encryption unit 226 may not be used depending on implementation. The storage interface unit 228 performs a data input / output interface with the storage unit 230, and the storage unit 230 stores the input data.

The DCAS unit 222 may download and store a CA system from the transmitting server, and performs a CA according to an appropriate CA system among the stored CA systems. The controller 218 controls the interface between the host and the cable card, data processing of the host, and the like.

In the case of the receiver described above, the interface between the host and the cable card may vary according to the format of data transmitted and received between the host and the cable card. Hereinafter, the interface between the host and the cable card and the data format to be transmitted and received will be described with reference to each embodiment.

In a first embodiment, IMP (IP MPEG Packet) data can be transmitted and received between the host and the cable card. The IMP packet refers to a packet in which a 12-byte preheader is added to the IP packet data as shown in FIG. However, the name is an example, and the spirit of the present invention is not limited to the name.

6 is a diagram illustrating a data flow in a receiver according to the first embodiment according to an embodiment of the present invention. The receiver of FIG. 6 represents the same receiver as the receiver of FIG. 2 described above. However, for convenience of description, the data received through the IP network channel and the data received through the cable broadcasting channel are shown mainly, and other blocks and the like will be omitted. It is also assumed that data coded according to the MPEG scheme is received.

As described above, the cable broadcast data may be received through the first tuner 202 and the second tuner 204, and the received data is demodulated by the QAM method in the demodulator 206 and multiplexed by the multiplexer 208. Will be printed). The output data has the form of MPEG-TS.

IP network channel data is received via the NIC portion 214, which is then routed from the network stack portion 216 to its destination. The network stack unit 216 of FIG. 6 is an example in which only an Ethernet layer, an IP layer, and a TCP / UDP layer are displayed among the network stacks. The network stack unit 216 classifies the received data into in-band data and OOB data, and transmits the OOB data to a cable card and the in-band data to the multiplexer 208. The transmitted OOB data and in-band data are data in the form of an IP packet including an IP header, a UDP header (or a TCP header), and a payload. In the case of OOB data, the payload includes OOB message data, and in in-band data, the payload includes MPEG TS.

The multiplexer 208 adds a 12-byte preheader to the MPEG-TS data received from the demodulator 206 and the IP packet data received from the network stack 216 to cable data in the form of IMP packets. Send to card. 'Local' of FIG. 6 refers to a preheader added by the multiplexer 208.

7 is a diagram schematically illustrating a structure of an IMP packet according to an embodiment of the present invention. The IMP includes 12 bytes of preheader, 20 bytes of IP header, 8 bytes of UDP (or TCP) header, and 188 bytes of payload (MPEG-TS).

The 12-byte preheader includes a local transport stream ID (LTSID) area, a reserved area (Res1, Res2), a host reserved area (HOSTres), a local time stamp (LTS) area, a cable card reserved area (CableCardres), CRC region is included. The LTSID region may include the LTSID information described above, and the host reserved region may include additional packet characteristic information generated by the host. The LTS region includes local time stamp information set in the host. The host may manage the MPEG packet timing by using the local time stamp information. The cable card reserved area can optionally be used on the cable card side. The CRC region includes CRC information for correcting an error of the preheader.

As described above, the IP packet data received from the network stack unit 216 may form the IMP packet by adding a 12-byte preheader. However, in the case of the MPEG-TS data received from the demodulator 206, a dummy IP header and a dummy UDP (or TCP) header are further required to form the above IMP packet. Accordingly, the multiplexer 208 adds a preheader to data received from the network stack 216, and preheader, dummy IP header, and dummy UDP (or TCP) to data received from the demodulator 206. Header to form an IMP packet. The dummy value is a value added to match the format of the IMP packet.

A data channel and an extended channel exist between the cable card and the host. The data channel is set to exchange control signals between the host and the cable card, and the extension channel is a channel set to exchange actual data. The expansion channel is a CPU interface defined to exchange data between the host and the cable card. That is, the cable card communicates with the transmitting side and interprets the command received from the transmitting side. Then, the cable card communicates with the host through the data channel and the extended channel to cause the transmitting side to perform the instruction, And transmits the contents to the transmitting side.

In this case, in order to transmit data through the extension channel, first, a transmission line corresponding to the data type defined between the cable card and the host must be set, which is called flow. For example, in order to transmit MPEG section data, an MPEG section flow may be set between a cable card and a host, and then actual MPEG section data may be transmitted on the flow. Flows on the expansion channel between the cable card and the host include a DSG (DOCSIS Settop Gateway) flow, an IP unicast (IP_U) flow, an IP multicast (IP_M) flow, and an MPEG section flow. As shown in FIG. 6, an OOB message in the form of an IP packet may be transmitted to a cable card using an IP_U flow or an IP_M flow.

The cable card 220 descrambles the data included in the payload of the IMP packet received from the host according to a conditional access system (CAS) or content protection (CP) scheme. The IMP packet including the descrambled data is transmitted back to the host.

The demultiplexer 210 of the host demultiplexes and receives the received IMP packet. When the IMP packet is received, the demultiplexer 210 removes the preheader included in the packet and processes data according to the LTSID information. For example, the preheader, the IP header, the UDP header (or the TCP header) included in the packet may be removed, and the data (MPEG-TS) included in the payload may be output to the decoder 212. Alternatively, the IP packet from which the preheader is removed may be stored in the storage 230 or the like, or only the payload data (MPEG-TS) may be stored in the storage 230 or the like according to the LTSID information.

As described above, an interface can be easily implemented by unifying data formats transmitted and received between the host and the cable card, and the logic of the cable card can be simplified.

In a second embodiment, CMP and IMP data may be transmitted and received between the host and the cable card. In the above example, data received through a cable broadcast channel and data received through an IP network channel are distinguished from each other to transmit and receive data.

8 is a diagram illustrating a data flow in a receiver according to a second embodiment according to an embodiment of the present invention. Similarly, the receiver of FIG. 8 represents the same receiver as the receiver of FIG. 2 described above.

As described above, the received cable broadcast data has an MPEG-TS form and is output to the multiplexer 208. The IP network channel data is transmitted to the multiplexer 208 via the NIC unit 214 and the network stack unit 216. The multiplexer 208 adds a 12-byte preheader to the MPEG-TS data received by the demodulator 206 to form a CMP packet, and 12 bytes to the IP packet data received by the network stack 216. The preheader is added to form an IMP packet. 'Local' of FIG. 8 refers to a preheader added by the multiplexer 208.

9 is a diagram schematically showing the structure of a CMP packet according to another embodiment of the present invention, and FIG. 10 is a diagram schematically showing the structure of an IMP packet according to an embodiment according to the present invention. The CMP includes 12 bytes of preheader and 188 bytes of payload (MPEG-TS), and the IMP includes 12 bytes of preheader, 20 bytes of IP header, 8 bytes of UDP (or TCP) header, and 188 bytes. Payload (MPEG-TS). The information of the preheader is as described with reference to FIG. 7, and the IMP of FIG. 7 and the IMP of FIG. 10 have the same structure.

As shown in FIG. 8, the OOB message in the form of an IP packet may be transmitted to a cable card using an IP_U flow or an IP_M flow. In-band data such as CMP, IMP packet, etc. may be transmitted and received between the cable card and the host using the MPEG section flow.

The cable card 220 descrambles data included in the payload of the CMP or IMP packet received from the host according to a Conditional Access System (CAS) or Content Protection (CP) scheme. The CMP or IMP packet including the descrambled data is transmitted back to the host.

The demultiplexer 210 of the host demultiplexes the packet received from the cable card. When the CMP packet is received, the demultiplexer 210 outputs data (MPEG-TS, etc.) included in the payload to the decoder 212 according to the LTSID information included in the preheader, or is included in the payload. Data may be stored in the storage 230.

When the IMP packet is received, the demultiplexer 210 outputs the data (MPEG-TS) included in the payload to the decoder 212 according to the LTSID information, or stores the data included in the payload 230. ) Can be stored. Alternatively, the IP packet from which the preheader has been removed may be stored in the storage 230.

At this time, the cable card 220 and the host demultiplexer 210 should distinguish the received CMP or IMP packet. In the cable card 220 and the demultiplexer 210, various methods may be used to identify the packet.

First, a scheme of identifying the packet by using a start of packet (SOP) such as MPEG-TS included in a payload may be used. When the cable card 220 receives a packet from the host, the cable card 220 checks whether the corresponding packet is CMP, and if not, checks whether the packet is IMP. Alternatively, depending on the implementation, it may first be checked whether the IMP.

That is, the cable card 220 moves from the first byte of the received packet by 12 bytes, which is the size of the preheader, and checks whether the value of the 13th byte is SOP. For example, in the case of MPEG2-TS, the SOP value is 0x47. Therefore, if the value of the 13th byte is the SOP value, the cable card 220 determines the received packet as CMP.

If it is determined that the CMP is not the case, the first byte is shifted by 40 bytes, which is the size of the preheader, the IP header, and the UDP (or TCP) header, and it is checked whether the value of the 41st byte is SOP. If the value of the forty-first byte is an SOP value, the cable card 220 determines that the received packet is an IMP. The above scheme may also be used when the host demultiplexer 210 identifies a packet.

Second, a scheme of identifying the packet using a reserved area included in the preheader of the packet may be used. For example, the multiplexer 208 inserts identification information identifying the packet into the reserved area included in the pre-header of the CMP and IMP, and transmits the identification information to the cable card 220.

The 12-byte preheader includes a local transport stream ID (LTSID) area, a reserved area (Res1, Res2), a host reserved area (HOSTres), a local time stamp (LTS) area, a cable card reserved area (CableCardres), CRC region is included. The multiplexer 208 inserts packet identification information into at least one of the reserved areas of Res1, Res2, HOSTres, and CableCardres. For example, a preheader is added to the data received from the demodulator 206 and converted into a CMP packet. At this time, the CMP packet identification information is inserted into the reserved area of the preheader. Data received from the network stack unit 216 is converted into an IMP packet, and at this time, IMP packet identification information is inserted into a reserved area of the preheader. The position of the reserved region into which the packet identification information is inserted may vary depending on implementation.

Table 1 below shows an example of inserting two bytes of packet ID information into a HOSTres region. In the case of CMP packets, the Packet ID field value in the HOSTres region has 0x01, and in the case of IMP packets, the Packet ID field value has 0x02.

Packet ID value Description 0x01 CableCard MPEG Packet (CMP) 0x02 IP MPEG Packet (IMP) 0x03 to 0xFF reserved for future use

The demultiplexer 210 of the cable card 220 and the host may identify the received packet by using the packet identification information included in the preheader. Alternatively, data may be transmitted / received in units of length of a corresponding packet using the identification information. By using the identification information as described above, it is easy to expand even when other types of packets are defined. In addition, it is possible to effectively support the interface between the cable card and the host for packets having different types of A / V.

Third, a method of identifying the packet using the transmission / reception signal of the packet may be used. For example, a signal indicating the start of a packet and a signal indicating the end of a packet may be transmitted and received between the cable card and the host to identify the packet.

11A and 11B are diagrams schematically illustrating a start signal and a end signal of a packet according to an embodiment of the present invention. 'MICLK' represents an MPEG transport stream clock signal transmitted from the host to the card side in the multi-stream mode, and 'MOCLK' represents an MPEG transport stream clock signal transmitted from the card side to the host in the multi-stream mode. 'MISTRT' is a signal indicating the start of a packet transmitted from the host to the card side, and 'MIEND' is a signal indicating the end of a packet transmitted from the host to the card side. 'MOSTRT' is a signal indicating the start of a packet transmitted from the card to the host side, and 'MOEND' is a signal indicating the end of a packet transmitted from the host to the card side. 'MDI' represents an MPEG transport stream input data bus transmitted from the host to the card side, and 'MDO' represents an MPEG transport stream output data bus transmitted from the card to the host side. The signals may be transmitted and received through the control unit as a kind of control signal between the host and the cable card. However, the name of the signal is only an example, and the spirit of the present invention is not limited by the name.

The 'MDI' data and the 'MISTRT' signal clock are input to the card side from the rising edge of the 'MICLK' clock, and the 'MDO' data and the 'MOSTRT' signal clock are the rising edge of the 'MOCLK' clock. To the host side. 200 bytes (preheader 12 bytes + MPEG TS 188 bytes) CMP packet or 228 bytes (preheader 12 bytes + IP header 20 bytes + UDP (or TCP) header with input of the 'MISTRT' clock signal from host to card side IMP packets of 8 bytes + MPEG TS 188 bytes) are transmitted. When the last byte of the packet is transmitted to the cable card, the 'MIEND' clock signal is transmitted to the cable card. Accordingly, the cable card may identify the type of packet by counting the number of bytes of data or the number of clocks of 'MICLK' received between the 'MISTRT' signal and the 'MIEND' signal. In this manner, the demultiplexer 210 of the host may identify the type of packet using the 'MOSTRT' signal and the 'MOEND' signal.

The 'MIEND' and 'MOEND' signals are recognized as 'MISTRT' or 'MOSRTR' signals when one clock is input using the existing 'MISTRT' and 'MOSRTR' signal systems as shown in FIG. 11A. When a plurality of clocks are input, the clock may be recognized as a 'MIEND' or 'MOEND' signal. Alternatively, the present invention may be implemented to transmit and receive a 'MIEND' or 'MOEND' clock signal independently of the existing 'MISTRT' and 'MOSRTR' signal systems. When different signal systems are used for the transmission start signal and the transmission end signal as shown in FIG. 11B, the clocks need not be distinguished. However, when the same signal system is used as in FIG. Should be distinguished.

By using the above-described method, even if other types of packets are defined, the types of packets can be easily identified. In addition, minor hardware modifications can effectively support the interface between the cable card and the host for packets with different types of A / V types.

12 is a flowchart illustrating a process of processing received data according to an embodiment of the present invention. 12 is a diagram illustrating a process of converting data received through a cable broadcast channel and data received through an IP network channel into IMP packets and transmitting and receiving them.

As described above, A / V data and the like may be received through the IP network channel and the cable broadcasting channel to the host of the receiver (S1200). The data may be received simultaneously in each channel or may be received in only one channel.

The host converts the received data into an IMP packet and multiplexes it (S1210). At this time, a 12-byte preheader is added to the data received through the IP network channel, and a 12-byte preheader, a dummy IP header, and a dummy UDP (or TCP) header are added to the data received through the cable broadcast channel. In this case, an LTSID or the like may be inserted into the preheader of the IMP packet.

The formed IMP packet is transmitted to the cable card (S1220), and the cable card descrambles data included in the payload of the received packet (S1230). The cable card transmits the IMP packet including the descrambled data back to the host (S1240).

The host decodes data included in the payload of the IMP packet received from the cable card (S1250). Alternatively, the descrambled data of the payload may be stored or an IP packet from which the preheader is removed may be stored according to a setting.

13 is a flowchart illustrating another process of processing received data according to an embodiment of the present invention. FIG. 13 is a diagram illustrating a process of converting data received through a cable broadcast channel into a CMP packet and converting data received through an IP network channel into an IMP packet.

As described above, A / V data and the like may be received through the IP network channel and the cable broadcasting channel to the host of the receiver (S1300). The data may be received simultaneously in each channel or may be received in only one channel.

If the received data is data received through an IP network channel (S1310), the host converts the received data into an IMP packet (S1320). If the received data is data received through a cable broadcast channel, the received data is converted into a CMP packet (S1330). In this case, an LTSID or the like may be inserted into the preheader of the IMP or CMP packet.

The formed IMP packet or CMP packet is transmitted to the cable card (S1340), and the cable card distinguishes the received packet and descrambles the data included in the payload (S1350). A method of using start of packet (SOP) information to distinguish the packet, a method of using packet identification information included in a preheader of a packet, or a method of using a start signal and an end signal of a packet may be used. Whether to use depends on the implementation.

The cable card transmits the CMP or IMP packet including the descrambled data back to the host (S1360). The host decodes data included in the payload of the IMP or CMP packet received from the cable card (S1370). Alternatively, the descrambled data of the payload may be stored or an IP packet from which the preheader is removed may be stored according to a setting.

In the example described above, a cable card is used, but a smart card may be used instead of the cable card.

In this embodiment, the descramble module is provided in the cable card or the smart card, and the card is detached from the host. The received broadcast signal is descrambled through the descramble module of the card and provided to the user. However, according to an embodiment, the descramble module is provided inside the host without the card, and the descramble module may be configured to be downloaded from a broadcasting station or a service provider. That is, the downloaded descrambling module may have a different configuration to be stored in a predetermined memory in the host. However, this configuration difference does not limit the scope of the present invention.

It is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

1 is a diagram schematically showing an IPTV system according to an embodiment of the present invention.

2 is a schematic view of a receiver using a cable card according to an embodiment of the present invention.

3 is a diagram illustrating the structure of an Ethernet frame according to an embodiment of the present invention.

4 is a diagram illustrating a structure of data routed to a multiplexer according to an embodiment of the present invention.

5 illustrates an LTSID table according to an embodiment of the present invention.

6 is a diagram illustrating a data flow in a receiver according to the first embodiment according to an embodiment of the present invention.

7 is a diagram schematically illustrating a structure of an IMP packet according to an embodiment of the present invention.

8 is a diagram illustrating a data flow in a receiver according to a second embodiment according to an embodiment of the present invention.

9 is a diagram schematically showing the structure of a CMP packet according to another embodiment of the present invention.

10 is a diagram schematically showing the structure of an IMP packet as an embodiment according to the present invention;

11A and 11B are diagrams schematically illustrating a start signal and a end signal of a packet according to an embodiment of the present invention.

12 is a flowchart illustrating a process of processing received data according to an embodiment of the present invention.

13 is a flowchart illustrating another process of processing received data according to an embodiment of the present invention.

DESCRIPTION OF THE REFERENCE NUMERALS

200: network connection unit 202: first tuner

204: second tuner 206: demodulator

208: multiplexing unit 210: demultiplexing unit

212: decoder 214: NIC part

216 network stack unit 218 control unit

220: cable card 222: DCAS unit

224: DVR control unit 226: content encryption unit

228: storage interface unit 230: storage unit

Claims (63)

delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete delete Receiving a frame including an Internet Protocol (IP) packet over a network, and receiving a Moving Picture Experts Group (MPEG) transport packet over a cable; Extracting the IP packet from the frame and routing the extracted IP packet based on destination information included in the frame; Generating an IP MPEG packet and a CableCARD MPEG packet by adding a packet header for transmitting identification information and packet identification information to each of the routed IP packet and the MPEG transport packet; And Multiplexing the IP MPEG packet and the cable card MPEG packet, and transmitting the multiplexed IP MPEG packet and the cable card MPEG packet to a point of deployment (POD), Wherein the packet identification information is information for identifying the IP MPEG packet or the cable card MPEG packet, and the routed IP packet includes an MPEG transpo packet. 45. The method of claim 44, wherein the destination information is at least one of a MAC address, an IP address, and a port number. 45. The method of claim 44, wherein the frame is an Ethernet frame including an Ethernet header, an IP packet, and an Ethernet CRC. 47. The method of claim 46, wherein extracting the IP packet from the frame And removing the Ethernet header and the Ethernet CRC from the frame. 45. The method of claim 44, wherein generating the IP MPEG packet is And determining the identification information with respect to the IP packet. 49. The method of claim 48, wherein the identification information is determined based on at least one of an IP address and a port number included in the IP packet. 45. The method of claim 44, wherein the identification information is a local transport stream identification ID (LTSID). 45. The method of claim 44, Receiving a packet from the POD, and detecting whether the received packet is an IP MPEG packet or a cable card MPEG packet based on packet identification information included in the packet. . 45. The method of claim 44, wherein the IP packet transmits at least one of video, audio, and service information. Receiving a packet from a host; Detecting whether the received packet is an IP MPEG packet or a cable card MPEG packet based on packet identification information included in the packet; Descrambling data transmitted to a payload field included in the detected packet; And Sending the packet to the host, The packet identification information is information for identifying the IP MPEG packet or the cable card MPEG packet, wherein the IP MPEG packet includes an IP packet, and the IP packet includes an MPEG transport packet. How data is processed. 55. The method of claim 53, wherein the packet identification information is transmitted in a packet header included in the packet. In the host device that interfaces with the POD, A broadband interface unit receiving an MPEG transport packet through a cable; An IP physical interface unit for receiving a frame including an IP packet through a network; A routing engine that extracts the IP packet from the frame and routes the extracted IP packet based on destination information included in the frame; A packet header for transmitting identification information and packet identification information is added to each of the routed IP packet and the MPEG transport packet to generate an IP MPEG packet and a cable card MPEG packet, and generate the IP MPEG packet and the cable card MPEG packet. A multiplexer for multiplexing and transmitting the multiplexed IP MPEG packet and cable card MPEG packet to the POD, Wherein the packet identification information is information for identifying the IP MPEG packet or the cable card MPEG packet, and the routed IP packet includes an MPEG transpo packet. 56. The host device of claim 55, wherein said destination information is at least one of a MAC address, an IP address, and a port number. 56. The host device of claim 55, wherein the frame is an Ethernet frame comprising an Ethernet header, an IP packet and an Ethernet CRC. 59. The system of claim 57 wherein the routing engine is And removing the Ethernet header and the Ethernet CRC from the frame. 56. The apparatus of claim 55, wherein the multiplexer And determine the identification information for the IP packet. 60. The host device of claim 59, wherein the multiplexer determines the identification information based on at least one of an IP address and a port number included in each of the IP packets. 56. The host device of claim 55, wherein said IP packet transmits at least one of video, audio, and service information. 56. The host device of claim 55, wherein said identification information is a local transport stream ID (LTSID). 56. The method of claim 55, And a demultiplexer for receiving a packet from the POD and detecting whether the received packet is an IP MPEG packet or a cable card MPEG packet based on packet identification information included in the packet.

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