CN107113321B

CN107113321B - Transmission apparatus and reception apparatus and signal processing method thereof

Info

Publication number: CN107113321B
Application number: CN201680005075.6A
Authority: CN
Inventors: 梁贤九; 黄盛凞
Original assignee: Samsung Electronics Co Ltd
Current assignee: Samsung Electronics Co Ltd
Priority date: 2015-01-07
Filing date: 2016-01-07
Publication date: 2020-06-30
Anticipated expiration: 2036-01-07
Also published as: CA2972882A1; MX2017008967A; MX367009B; KR20160085201A; CA3022469A1; CA2972882C; CN107113321A

Abstract

Disclosed is a transmission device including: a packet generator generating a packet including a header and a payload from an input stream including a plurality of Transport Stream (TS) packets; and a signal processor which performs signal processing on the packet, wherein the header includes a basic header including: a first field indicating a packet type, the packet type being a TS packet; and a second field indicating a number of TS packets included in the payload, wherein the base header further includes a third field set to a first value indicating that no additional header exists or a second value indicating that an additional header exists, wherein when the third field is set to the second value, the additional header includes a fourth field indicating a number of null packets deleted with respect to each of at least one TS packet group including consecutive TS packets, and wherein the null packets deleted with respect to each of the TS packet groups are before a first TS packet included in each of the TS packet groups or after a last TS packet.

Description

Transmission apparatus and reception apparatus and signal processing method thereof

Technical Field

Apparatuses and methods consistent with exemplary embodiments relate to a transmitting apparatus and a receiving apparatus and signal processing methods thereof, and more particularly, to a transmitting apparatus and a receiving apparatus which transmit data by mapping the data to at least one signal processing path and signal processing methods thereof.

Background

In the 21 st century of information-oriented society, broadcast communication services are entering the era of digitization, multi-channel, broadband, and high quality. In particular, as high-quality digital Televisions (TVs), Portable Multimedia Players (PMPs), and portable broadcasting devices are increasingly used in recent years, demand for digital broadcasting services capable of supporting various reception methods is increasing. In addition, the demand for data transmission of various packets composed of Moving Picture Experts Group (MPEG) 2-Transport Stream (TS) packets and internet protocol-based packets, which have been conventionally used through broadcasting networks, is also increasing.

Accordingly, broadcast communication standards organizations have established various standards in accordance with this demand in order to provide various services to meet the needs of users. However, there is still a need for a method of providing a better broadcast communication service with more excellent performance by using general-purpose data.

Disclosure of Invention

Technical problem

Exemplary embodiments of the inventive concept may overcome the above disadvantages and other disadvantages not described above. However, the exemplary embodiments do not need to overcome the disadvantages described above, and may not overcome any of the problems described above.

The present invention has been made to solve the problems as needed, and an object of the present invention is to provide a transmitter, a receiver, and a signal processing method thereof that generate packets having a format suitable for transmitting TS packet type data.

Technical solution

According to an aspect of the exemplary embodiments, there is provided a transmission apparatus including: a packet generator generating a packet including a header and a payload from an input stream including a plurality of Transport Stream (TS) packets; and a signal processor which performs signal processing on the packet, wherein the header includes a basic header including: a first field indicating a packet type, the packet type being a TS packet; and a second field indicating a number of TS packets included in the payload, wherein the base header further includes a third field set to a first value indicating no additional header or a second value indicating that an additional header exists, wherein when the third field is set to the second value, the additional header includes a fourth field indicating a number of null packets deleted with respect to each of at least one TS packet group including consecutive TS packets, and wherein the null packets deleted with respect to each of the TS packet groups are ahead of a first TS packet included in each of the TS packet groups or behind a last TS packet included in each of the TS packet groups.

According to an aspect of another exemplary embodiment, a signal processing method of a transmission apparatus is provided. The method can comprise the following steps: generating a packet including a header and a payload from an input stream, the input stream including a plurality of Transport Stream (TS) packets; and signal processing the generated packet, wherein the header includes a base header, the base header including: a first field indicating a packet type, the packet type being a TS packet; and a second field indicating a number of TS packets included in the payload, wherein the base header further includes a third field set to a first value indicating no additional header or a second value indicating that an additional header exists, wherein when the third field is set to the second value, the additional header includes a fourth field indicating a number of null packets deleted with respect to each of at least one TS packet group including consecutive TS packets, and wherein the null packets deleted with respect to each of the TS packet groups are ahead of a first TS packet included in each of the TS packet groups or behind a last TS packet included in each of the TS packet groups.

Advantageous effects

According to various exemplary embodiments, since an input stream can be efficiently mapped to a physical layer, data processing efficiency may be improved.

Additional and/or other aspects and advantages of the inventive concepts will be set forth in part in the description which follows and, in part, will be obvious from the description, or may be learned by practice of the embodiments of the invention.

Drawings

The foregoing and/or other aspects of the present inventive concept will be more readily apparent by describing certain exemplary embodiments with reference to the accompanying drawings, in which:

fig. 1 is a diagram showing a hierarchical structure of a transmission system according to an exemplary embodiment;

fig. 2 is a diagram showing a schematic configuration of a broadcast link layer according to an exemplary embodiment;

fig. 3A is a diagram showing a schematic configuration of a transmission system (or a transmission apparatus) according to an exemplary embodiment;

fig. 3B and 3C are diagrams illustrating a multiplexing method according to an exemplary embodiment;

fig. 4 to 5B are block diagrams illustrating a detailed configuration of the input formatting block illustrated in fig. 3A according to an exemplary embodiment;

fig. 6 is a block diagram showing a configuration of a transmission apparatus according to an exemplary embodiment;

fig. 7 is a diagram illustrating an ATSC 3.0 link layer protocol (ALP) packet structure according to an exemplary embodiment;

fig. 8 is a diagram illustrating a structure of a basic header of an ALP packet according to an exemplary embodiment;

FIG. 9 is a diagram depicting a null packet deletion mechanism in accordance with an illustrative embodiment;

fig. 10 is a diagram describing a Transport Stream (TS) header deletion mechanism according to an exemplary embodiment;

fig. 11 is a block diagram showing a configuration of a transmission apparatus according to another exemplary embodiment;

fig. 12 is a block diagram showing a detailed configuration of a frame generator according to an exemplary embodiment;

fig. 13 is a diagram illustrating an ALP packet, a baseband packet, and a scrambled baseband packet according to an exemplary embodiment;

fig. 14 is a diagram describing a TS packet encapsulation mechanism according to an exemplary embodiment;

fig. 15 is a diagram describing a TS packet encapsulation mechanism according to another exemplary embodiment;

fig. 16 is a diagram illustrating a decapsulating mechanism of an ALP packet shown in fig. 15 according to an exemplary embodiment;

fig. 17 is a diagram describing a TS packet encapsulation and TS header deletion mechanism according to another exemplary embodiment;

fig. 18 is a diagram for describing a mechanism of decapsulation and TS header recovery for the ALP packet shown in fig. 17;

fig. 19 is a flowchart describing a signal processing method of a transmission apparatus according to an exemplary embodiment;

fig. 20A is a block diagram showing a configuration of a reception apparatus according to an exemplary embodiment;

fig. 20B is a block diagram illustrating in detail a signal processor according to an exemplary embodiment;

fig. 21 is a block diagram showing a configuration of a receiver according to an exemplary embodiment;

FIG. 22 is a block diagram illustrating the demodulator of FIG. 21 in greater detail according to an example embodiment;

fig. 23 is a flowchart schematically illustrating an operation of a receiver from a time when a user selects a service to a time when the selected service is actually reproduced according to an exemplary embodiment;

fig. 24A is a block diagram showing a configuration of a reception apparatus according to an exemplary embodiment;

fig. 24B is a block diagram illustrating in detail a signal processor according to an exemplary embodiment;

fig. 25 is a block diagram showing a configuration of a receiver according to an exemplary embodiment;

FIG. 26 is a block diagram illustrating the demodulator shown in FIG. 25 in greater detail according to an example embodiment; and

fig. 27 is a flowchart schematically illustrating an operation of a receiver from a time when a user selects a service to a time when the selected service is actually reproduced according to an exemplary embodiment.

Best mode for carrying out the invention

Detailed Description

Hereinafter, exemplary embodiments of the inventive concept will be described in detail with reference to the accompanying drawings.

The apparatus and method proposed in the exemplary embodiments can be applied to various communication systems including: mobile broadcasting services including a Digital Multimedia Broadcasting (DMB) (hereinafter, referred to as 'DMB') service, a digital video broadcasting-handheld (DVB-H) (hereinafter, referred to as 'DVP-H'), a mobile/handheld advanced television systems committee (ATSC-M/H) (hereinafter, referred to as 'ATSC-M/H') service, an Internet Protocol Television (IPTV) service (hereinafter, referred to as 'IPTV') service, etc.; a communication system including a Moving Picture Experts Group (MPEG) media transport (MMT) (hereinafter, referred to as 'MMT') system, an Evolved Packet System (EPS) (hereinafter, referred to as 'EPS'), a Long Term Evolution (LTE) (hereinafter, referred to as 'LTE') mobile communication system, a Long term evolution-advanced (LTE-A) (hereinafter, referred to as 'LTE-A') mobile communication system, a High Speed Downlink Packet Access (HSDPA) (hereinafter, referred to as 'HSDPA') mobile communication system, a High Speed Uplink Packet Access (HSUPA) (hereinafter, referred to as 'HSUPA') mobile communication system, a High Rate Packet Data (HRPD) (hereinafter, referred to as 'HRPD') mobile communication system of 3GPP2) (hereinafter, referred to as '3 GPP 2'), a Wideband Code Division Multiple Access (WCDMA) (hereinafter, referred to as 'WCDMA') mobile communication system of 3GPP2, A Code Division Multiple Access (CDMA) (hereinafter, referred to as 'CDMA') mobile communication system of 3GPP2, an Institute of Electrical and Electronics Engineers (IEEE) (hereinafter, referred to as 'IEEE') 802.16m communication system, a mobile internet protocol (mobile IP) (hereinafter, referred to as 'mobile IP') system, and the like.

Fig. 1 is a diagram illustrating a hierarchical structure of a transmission system according to an exemplary embodiment.

Referring to fig. 1, a service includes media data 1000 and signaling 1050 for transmitting information required by a receiver in order to receive and consume the media data. The media data may be encapsulated prior to transmission in a format suitable for transmission. The encapsulation method may follow the Media Processing Unit (MPU) defined in ISO/IEC 23008-1 MPEG MMT or the HTTP dynamic adaptive streaming media (DASH) segment format defined in ISO/IEC23009-1 DASH. Media data 1000 and signaling 1050 are packetized based on an application layer protocol.

Fig. 1 shows a case where an MMT protocol (MMTP)1110 and a unidirectional transport real-time object delivery (ROUTE) protocol 1120 defined by MMT are used as application layer protocols. In this case, the receiver needs a method of informing information about an application layer protocol, in which a service is transmitted independently of the application layer protocol, in order to know through which application layer protocol the specific service is transmitted.

The Service List (SLT)1150 shown in fig. 1 constructs information on services through a table and packetizes the information in a signaling method to satisfy the above object. Details of the SLT will be described below. The packetized media data and signaling including the SLT are transmitted to the broadcast link layer 1400 through a User Datagram Protocol (UDP)1200 and an Internet Protocol (IP) 1300. Examples of the broadcast link layer include the ATSC 3.0 link layer protocol (ALP) defined in ATSC 3.0. The ALP generates an ALP packet through an IP packet as an input and transfers the ALP packet to the broadcast physical layer 1500.

However, according to fig. 2 described below, it should be noted that the broadcast link layer 1400 does not use only the IP packet 1300 including media data and/or signaling as an input, but instead it may use MPEG2-TS packets or general-format packetized data as an input. In this case, signaling information required for controlling the broadcast link layer is also transferred to the broadcast physical layer 1500 in the form of an ALP packet.

The broadcast physical layer 1500 generates a physical layer frame by signal processing with the ALP packet as an input, converts the physical layer frame into a Radio Frequency (RF) signal, and transmits the RF signal. In this case, the broadcast physical layer 1500 has at least one signal processing path. Examples of signal processing paths may include the physical layer channel (PLP) of DVB-T2 or ATSC 3.0, and all of one or more services or some of the services may be mapped to PLPs.

Fig. 2 is a diagram showing a schematic configuration of a broadcast link layer 1400 according to an exemplary embodiment.

Referring to fig. 2, the input to the broadcast link layer 1400 includes IP packets 1300, and may also include link layer signaling 1310, MPEG2-TS packets 1320, and other packetized data 1330.

Prior to the ALP packetization 1450, the input data may undergo additional signal processing based on the type of input data. As an example of additional signal processing, the IP packet 1300 may be subjected to an IP header deletion process 1410, and the MPEG2-TS packet may be subjected to a header reduction (or overhead reduction) process 1420. During ALP packetization, input packets may go through a split and merge process.

Fig. 3A is a diagram showing a schematic configuration of a transmission system or apparatus according to an exemplary embodiment. According to fig. 3A, a transmission system 10000 according to an exemplary embodiment may include input formatting blocks (or portions) 11000 and 11000-1, Bit Interleaving and Coded Modulation (BICM) blocks 12000 and 12000-1, framing/interleaving blocks 13000 and 13000-1, and waveform generation blocks 14000 and 14000-1.

Input formatting blocks 11000 and 11000-1 generate baseband packets from input streams that include data to be serviced. Here, the input stream may be at least one of a Transport Stream (TS), an IP packet (e.g., IPv4 and IPv6), an MMT stream, a General Stream (GS), a General Stream Encapsulation (GSE), and the like. For example, ALP packets may be generated from the input stream and baseband packets may be generated from the ALP packets.

The BICM blocks 12000 and 12000-1 determine a Forward Error Correction (FEC) coding rate and a constellation order according to a region (a fixed PHY frame or a mobile PHY frame) through which data to be serviced will be transmitted, and perform coding and perform time interleaving on the coded data. Meanwhile, the signaling signal (also referred to as signaling information) of the data to be served may be encoded by a separate BICM encoder or by the same BICM encoder that decodes the data to be served, depending on the system implementation.

Framing/interleaving blocks 13000 and 13000-1 combine the time-interleaved data with the signaling signals to generate a transmission frame.

The waveform generation blocks 14000 and 14000-1 generate an Orthogonal Frequency Division Multiplexing (OFDM) signal from the generated transmission frame in a time domain, modulate the generated OFDM signal into an RF signal, and transmit the RF signal to a receiver.

The transmission system 10000 according to the exemplary embodiment shown in fig. 3A includes a standard block marked with a solid line and an information block marked with a dotted line. Here, the block marked with a solid line is a standard block, and the block marked with a dotted line is a block that can be used when implementing an information Multiple Input Multiple Output (MIMO) system.

Fig. 3B and 3C are diagrams illustrating a multiplexing method according to an exemplary embodiment.

FIG. 3B illustrates a block diagram implementing Time Division Multiplexing (TDM), according to an example embodiment.

In TDM system architectures, there are four main blocks: an input formatting block 11000, a BICM block 12000, a framing/interleaving block 13000, and a waveform generation block 14000.

Data is input to and formatted in an input formatting block 11000. Next, in BICM block 12000, FEC is applied to the data and the data is mapped to the constellation. Subsequently, in the framing/interleaving block 13000, the data is time and frequency interleaved and a frame is generated. Finally, an output waveform is generated in the waveform generation block 14000.

Fig. 3C illustrates a block diagram implementing hierarchical multiplexing (LDM), according to an example embodiment.

In contrast to TDM system architectures, there are several other blocks in LDM system architectures. Specifically, the LDM system architecture includes two separate input formatting blocks 11000 and 11000-1 and BCIM blocks 12000 and 12000-1 for one of the respective layers of LDM. The blocks are combined in an LDM injection block before the framing/interleaving block 13000. In addition, the waveform generation block 14000 is similar to TDM.

Fig. 4 is a block diagram illustrating a detailed configuration of an input formatting block illustrated in fig. 3A according to an exemplary embodiment.

As shown in fig. 4, the input formatting block 11000 includes three blocks that can control packets to be formatted and allocated to PLPs. Specifically, the input formatting block 11000 includes an encapsulation and compression block 11100, a baseband formatting block (alternatively referred to as a baseband framing block) 11300, and a scheduler block 11200.

The input stream to the encapsulation and compression block 11100 may be constructed of various types. For example, the input stream may be at least one of a TS, an IP packet (e.g., IPv4 and IPv6), an MMT stream, a GS, a GSE, and the like.

The packets output from the encapsulation and compression block 11100 become ALP packets, which are general purpose packets or are referred to as layer 2(L2) packets. Herein, the format of the ALP packet may be one of a Type Length Value (TLV), GSE, and ALP.

The length of each ALP packet is variable. The length of the ALP packet can be easily extracted from the ALP packet itself without additional information. The maximum length of the ALP packet is 64 kB. The maximum length of the header of the ALP packet may be 4 bytes. The ALP packet has a length of an integer number of bytes.

The scheduler block 11200 receives an input stream including encapsulated ALP packets to form a physical layer channel (PLP) in the form of a baseband packet. In the TDM system, only one PLP (referred to as a single PLP (S-PLP)) or a plurality of PLPs (M-PLPs) may be used. One service may capture the use of four or more PLPs. In an LDM system consisting of two layers, one, i.e. two PLPs, is used per layer.

The scheduler block 11200 receives the encapsulated ALP packets to specify how the encapsulated ALP packets are allocated to physical layer resources. In particular, scheduler block 11200 specifies how baseband formatting block 1130 outputs baseband packets.

The function of the scheduler block 11200 is defined by data size and time. The physical layer may transmit some data in a distributed time. Using inputs and information such as constraints and configuration of the encapsulated packets, quality of service metadata of the encapsulated packets, system buffer models and system management, the scheduler block generates a solution that is appropriate in terms of configuration of physical layer parameters. The solution is a target of available configuration and control parameters and total spectrum.

At the same time, the operation of the scheduler block 11200 is constrained by a set of dynamic, quasi-static, and static components. The definition of the constraints may vary depending on the system design.

In addition, a maximum of four PLPs may be used with respect to each service. Multiple services including multiple types of interleaving blocks may be implemented by up to 64 PLPs with respect to a bandwidth of 6, 7, or 8 MHz.

The baseband formatting block 11300 includes baseband packet building blocks 3100, 3100-1, …, 3100-n, baseband packet header building blocks 3200, 3200-1, …, 3200-n, and baseband packet scrambling code blocks 3300, 3300-1, …, 3300-n, as shown in FIG. 5A. In M-PLP operation, the baseband formatting block generates a plurality of PLPs as necessary.

Base band package building blocks 3100, 3100-1, …, 3100-n build base band packages. Each baseband packet 3500 includes a header 3500-1 and a payload 3500-2, as shown in fig. 5B. The base-band package is secured to a length Kpayload. The ALP packets 3610 to 3650 are sequentially mapped to the baseband packet 3500. When the ALP packets 3610 to 3650 are not completely fitted in the baseband packet 3500, these packets are distributed between the current baseband packet and the next baseband packet. The ALP packet is distributed in units of bytes.

Baseband packet header building blocks 3200, 3200-1, …, 3200-n build a header 3500-1. The header 3500-1 includes three parts, that is, a basic field (also referred to as a basic header) 3710, an optional field (also referred to as an optional header) 3720, and an extension field (also referred to as an extension header) 3730, as shown in fig. 5B. Here, a basic field 3710 is shown in each baseband packet, and an optional field 3720 and an extension field 3730 may not be shown in each baseband packet.

The main function of the basic field 3710 is to provide a pointer as an offset value of bytes to indicate the start of the next ALP packet in the base band packet. When an ALP packet starts in the baseband packet, the value of the indicator becomes 0. When no ALP packet starts in the baseband packet, the value of the pointer may be 8191 and a 2-byte basic header may be used.

Extension field 3730 may then be used, for example, for baseband packet counter, baseband packet timestamp, additional signaling, and so forth.

The baseband packet scrambling blocks 3300, 3300-1, …, 3000-n scramble the baseband packets.

Similar to the case where payload data mapped to a constellation is configured by a repeated sequence, the payload data is successively scrambled before directional error correction coding in order to prevent successive mapping to the same point.

Fig. 6 is a block diagram illustrating a configuration of a transmission apparatus according to an exemplary embodiment of the present disclosure.

Referring to fig. 6, the transmission apparatus 100 includes a packet generator 110 and a signal processor 120.

The packet generator 110 may encapsulate an IP packet, a TS packet, and various types of data to generate packets and transmit the packets to the corresponding PLP. Here, the package corresponds to the L2 package in the ISO 7 layer model.

In particular, the packet generator 110 may generate packets, e.g., ALP packets (also referred to as generic packets or L2 packets), including a header and a payload (also referred to as a data payload) from an input stream. Here, the header may include information on a payload included in the corresponding packet and information on a packet included in the corresponding packet. Hereinafter, for convenience of description, the packet generated by the packet generator 110 will be referred to as an ALP packet.

In general, the payload of the ALP packet may include at least one of an IP packet, a TS packet, and a signaling packet. The data included in the payload is not limited to a specific example, and the payload may include various types of data including media data. Here, the ALP packet can be regarded as a unit packet required to map various types of data to a physical layer.

As described later in detail with reference to fig. 7 and 8A, the ALP packet may include a header formed of a basic header, an extra header, and an optional header. The base header may include first to third fields. The first field may indicate a packet type of the input stream, and when the first field is set to a value indicating that the packet type of the input stream is a TS packet, the second field may indicate the number of TS packets included in the payload, and the third field may be set to a first value indicating that there is no additional header or a second value indicating that there is an additional header.

Further, when the third field is set to the second value, the additional header may include a fourth field indicating that: the number of empty packets is deleted with respect to each of at least one TS packet group composed of consecutive TS packets. Here, the null packets deleted with respect to each TS packet group may be: the empty TS packet immediately preceding the first TS packet included in each TS packet group among the plurality of packets included in the input stream. However, according to an exemplary embodiment, the null packets deleted with respect to each TS packet group may be: an empty TS packet immediately following the last TS packet included in each TS packet group among a plurality of packets included in the input stream. When the number of TS packet groups included in the payload of the ALP packet is one, the fourth field may include only the number of deleted empty TS packets in the single TS group.

Meanwhile, when there is a deleted empty TS packet or when TS header (or referred to as TS packet header) compression is applied, the third field may be set to a second value.

In addition, when the third field is set to a second value, the additional header may include a fifth field indicating whether TS header compression is applied.

Herein, the fourth field is implemented by a 7-bit field, and when the fifth field is set to a fourth value indicating that no TS header compression is applied, the fourth field may be set to 0 in the case of deleting 128 null packets. Further, when the fifth field is set to a fifth value indicating that TS header compression is applied, the fourth field may be set to 0 without deleting a TS null packet.

The signal processor 120 may perform signal processing on the ALP packet generated by the packet generator 110. Here, the signal processor 130 may perform all signal processing procedures after generating the ALP packet, and for example, perform all signal processing procedures from generating the baseband packet to generating the transmission frame.

Fig. 7 is a diagram illustrating an ALP packet structure according to an exemplary embodiment.

Referring to fig. 7, the ALP packet includes a header 7100 and a payload 7200. Header 7100 may include a basic header 7110, an extra header 7120, and an optional header 7130. The ALP packet header 7100 always includes a basic header 7110, and whether an additional header 7120 is present in the header 7100 may be changed according to a control field value of the basic header 7110. In addition, whether the option header 7130 exists may be selected by using a control field of the additional header 7130.

Fig. 8A is a diagram illustrating a header structure of an ALP packet according to an exemplary embodiment.

The Packet _ Type field 7111 corresponds to a first field of the basic header 7110 as described above, and is a 3-bit field indicating a protocol applied to an input Packet or a Packet Type of the input Packet before being encapsulated into an ALP Packet. As an example, the Packet _ Type field 7111 may be encoded according to table 1 below.

[ TABLE 1 ]

Packet _ Type value	Means of
		000	IPv4 packet
001	Retention
		010	Compressed IP packets
011	Retention
		100	Link layer signaling packet
101	Retention
		110	Packet type extension
111	MPEG-2 transport stream

When the Packet _ Type field 7111 is set to a value '111' indicating that it is an MPEG-2TS Packet, the base header 7110 includes a TS Packet Number (NUMTS) field 7112. Here, the basic header 7110 also includes an extra header flag (AHF) field 7113. In other words, the header structure of the ALP packet shown in FIG. 8A is a header when the input stream is an MPEG-2TS packet.

A TS packet Number (NUMTS) field 7112 corresponds to the second field of the basic header 7110 as described above, and is a 4-bit field indicating the number of TS packets included in the payload of the ALP packet. NUMTS ═ 0' can indicate that 16 packets are transmitted in the payload of the ALP packet, and all other values of NUMTS can indicate an equal number (i.e., the same value) of TS packets. For example, NUMTS ═ 0001' indicates that one TS packet is transmitted. However, according to another implementation example, NUMT ═ k may indicate that k +1 TS packets are transmitted in the payload of the ALP packet.

An extra header flag (AHF) field 7113 corresponds to the third field of the basic header 7110 as described above, and is a 1-bit field indicating whether or not an extra header exists. A value of '0' indicates that there is no extra header, and a value of '1' indicates that there is an extra header 7120 after the basic header 7110. Here, the extra header may be implemented by 1 byte. The AHF field 7113 may be set to a value of '1' when an empty TS packet is deleted or when a TS packet header deletion is implemented. In other words, the additional header 7120 for TS packet encapsulation is composed of a Deleted Null Packet (DNP) field 7121 and a Header Deletion Mode (HDM) field 7122, and is present only when the AHF field 7113 is set to a value of '1'.

Specifically, the sync byte (0 × 47) of each TS packet is continuously deleted, and thus, the length of the MPEG-2TS packet encapsulated in the payload of the ALP packet is continuously changed to 187 bytes, rather than its original length of 188 bytes.

In particular, to avoid unnecessary transport overhead, null TS packets (PID 0 × 1FFF) may be deleted and the deleted null TS packets may be recovered by the receiver side using the DNP field 7121.

The DNP field 7121 corresponds to the fourth field as described above, and indicates the number of deleted empty TS packets. Here, the deleted empty TS packet may be: at least one empty TS packet immediately preceding or immediately following a first TS packet or a last TS packet in each TS packet group included in the ALP packet payload, among a plurality of packets included in the input stream.

Fig. 8B is a diagram illustrating a header structure of an ALP packet according to another exemplary embodiment.

As an overhead reduction mechanism of the MPEG-2TS packet for improving transmission efficiency, TS header deletion may be selectively applied. At least two consecutive TS packets have consecutive counter fields that are sequentially increased, and when the headers of the TS packets are the same, the headers may be transmitted once in the first packet and the other headers may be deleted.

When the three overhead reduction mechanisms are performed, the overhead reduction may be performed successively in the order of sync byte deletion, null packet deletion, and common header deletion. The syntax of the MPEG-2TS encapsulation is shown in Table 2.

[ TABLE 2 ]

The HDM field 7122 corresponds to the fifth field of the basic header 7110 as described above, and is a 1-bit field indicating whether to apply TS header deletion to the ALP packet. A value of '1' indicates that TS header deletion is applied to the ALP packet, and a value of '0' indicates that TS header deletion is not applied.

Meanwhile, up to 128 null packets may be deleted. When the value of the HDM field 7121 is "0", the value of '0' of the DNP field 7122 indicates that 128 null TS packets are deleted. When the value of the HDM field 7121 is "1", a value of '0' of the DNP field 7122 indicates that the empty TS packet is not deleted. A value of '0' of the HDM field 7121 indicates that TS header deletion is not applied and null TS packets are deleted.

When the AHF field 7113 is set to a value of "1", there is an extra header 7120, which also means that an empty TS packet is deleted or TS header compression is applied. Therefore, when the value of the HDM field 7121 is "0", since the value of the DNP field 7122 does not need to indicate whether to delete empty TS packets, the value "0" in the HDM field 7121 indicates that 128 empty TS packets are deleted. In contrast, when the value of the HDM field 7121 is "1", at least one empty TS packet may be deleted or not deleted. Therefore, when the value of the HDM field 7121 is "1", the value '0' of the DNP field 7122 indicates that the empty TS packet is not deleted.

All values of the DNP field 7122 except for the value '0' are the same as the number of deleted empty TS packets. For example, a value of "5" for the DNP field 7122 indicates that 5 null packets are deleted.

The AHF field 7113 corresponds to the third field of the basic header 7110 as described above, and is a 1-bit field indicating whether or not there is an additional header. A value of '0' indicates that there is no extra header, and a value of '1' indicates that there is an extra header 7120 after the basic header 7110. Here, the extra header may be implemented as 1 byte. The AHF field 7113 may be set to a value of '1' when an empty TS packet is deleted or when a TS packet header deletion is applied.

In other words, the TS packet encapsulated extra header 7120 includes an HDM field 7122 and a DNP field 7121 and is present only when the AHF field 7113 is set to a value of '1'.

The HDM field 7121 corresponds to the fifth field as described above and is a 1-bit field indicating whether to apply TS header deletion to ALP packets. A value of '1' indicates that TS header deletion is applied to the ALP packet, and a value of '0' indicates that TS header deletion is not applied.

The DNP field 7122 corresponds to the fourth field as described above, and indicates the number of deleted empty TS packets. Here, the deleted empty TS packet may be: at least one empty TS packet immediately preceding or immediately following a first TS packet or a last TS packet in each TS packet group included in the ALP packet payload, among a plurality of packets included in the input stream.

Up to 128 null packets may be deleted. When the value of the HDM field 7121 is '0', the value '0' of the DNP field 7122 indicates that 128 null TS packets are deleted. When the value of the HDM field 7121 is '1', the value of '0' of the DNP field 7122 indicates that no empty TS packet is deleted. Since the value '0' of the HDM field 7121 indicates that TS header deletion is not applied, the value '0' indicates that an empty TS packet is specifically deleted.

Fig. 9 is a diagram depicting a null packet deletion mechanism in accordance with an illustrative embodiment.

In some transport stream input signals, null packets may be present in order to receive a variable bit rate service in a predetermined bit rate stream, in which case, to prevent unnecessary transmission overhead, null TS packets (PID 0 × 1FFF) may be deleted, a process of reinserting the deleted null TS packets into the original location in the receiving device is performed, whereby a predetermined bit rate may be guaranteed, and Program Clock Reference (PCR) timestamp updates may not be required.

Before generating the ALP packets, a counter called DNP is reset to zero and is incremented with the corresponding deleted empty TS packet before being encapsulated into the ALP packet.

A set of consecutive valid TS packets is encapsulated into the payload of the ALP packet and each field value of the header is determined. After injecting the generated ALP packet into the physical layer, the DNP is reset to zero. In case the DNP reaches the maximum, when the next packet is also a null packet, this null packet is considered as a valid packet and encapsulated into the payload of the next ALP packet. Each ALP packet includes at least one valid TS packet in the payload.

Fig. 9 shows HDM ═ 0 'and AHF ═ 1' relative to two ALP packets. In the first ALP packet 910, one null packet is deleted before two valid TS packets are transmitted to the ALP packet 910. When the next packet is an empty packet, the ALP packet 910 is complete and the DNP counter is reset to zero. In the header of the ALP packet 910, NUMT ═ 2 'and DNP ═ 1'. In the second ALP packet 920, two null packets are deleted before four valid TS packets are transmitted to the ALP packet 920. In this case, in the header corresponding to the ALP packet 920, num ═ 4 'and DNP ═ 2'.

Fig. 10A and 10B are diagrams describing a null packet deletion mechanism according to another exemplary embodiment.

As shown in fig. 10A and 10B, the DNP field 1010 may include the number of deleted null packets with respect to each of a plurality of TS packet groups composed of consecutive TS packets. Here, the deleted null packets with respect to the respective

TS packet groups

1021, 1022, and 1023 may be

null packet groups

1031, 1032, and 1033 that include a plurality of null TS packets immediately preceding a first TS packet included in each TS packet group among a plurality of packets included in the input stream.

The DNP indicator field 1011 is a field indicating whether or not there is an empty packet deleted with respect to each TS packet group. The i-th bit of the DNP indicator field indicates whether there is an empty TS packet deleted before the i-th TS packet in the payload of the ALP packet. For example, when the number of valid TS packets transmitted in the ALP packet is 8 or less, the DNP indication field 1050 may become 1 byte. Further, when the number of valid TS packets transmitted in the ALP packet is greater than 8 but equal to or less than 16, the DNP indication word field 1011 may become 2 bytes.

The DNP fields 1012, 1013, and 1014 respectively indicate the number of null TS packets deleted with respect to the deleted consecutive null TS packet group. For example, each

DNP field

1012, 1013, and 1014 may be implemented as 8 bits.

As shown in fig. 10B, the

numbers

1041, 1042, and 1043 of

null packets

1031, 1032, and 1033 deleted with respect to three

TS packet groups

1021, 1022, and 1023 each constituted by consecutive valid TS packets are counted, respectively, and the counted numbers of null packets may be included in

DNP fields

1012, 013, and 1014, respectively, of the ALP packet header 1100. Here, the

null packets

1031, 1032, and 1033 deleted with respect to the respective

TS packet groups

1021, 1022, and 1023 may be

null packet groups

1031, 1032, and 1033 including a preceding null TS packet immediately preceding a first TS packet included in each TS packet group among a plurality of packets included in the input stream.

Fig. 11 is a diagram describing a TS header deletion mechanism according to another exemplary embodiment.

At least two consecutive TS packets successively increment the continuity counter field, and when the header fields of these TS packets are the same (in other words, redundant), the header is transmitted once in the first packet, and the other headers are deleted. Header deletion is applied at the transmitter side when the copied MPEG-2TS packet is included in at least two consecutive TS packets. The HDM field indicates whether header deletion is performed. When the TS packet header is deleted, the HDM field is set to '1'.

Fig. 11 illustrates an exemplary embodiment when three TS packets have the same header field and NUMT ═ 4'. When AHF ═ 1 ', HDM ═ 1 ' and NDP ═ 0 '. In other words, in this case, TS header deletion is applied and null packet deletion is not applied. At the receiver side, the deleted packet header is restored by using the first packet (1010) header, and the continuity counter is successively incremented and restored from the first header.

Fig. 12 is a block diagram illustrating a configuration of a transmission apparatus according to another exemplary embodiment. Referring to fig. 12, the transmission apparatus 100' includes a packet generator 110, a frame generator 130, a signal processor 140, and a transmitter 150. In the components shown in fig. 12, since the configuration of the packet generator 110 is the same as that of the packet generator 110 shown in fig. 6, a detailed description will be omitted.

The packet generator 110 generates a packet, for example, an ALP packet (general packet) as described above.

The frame generator 130 may generate a frame including the ALP packet generated by the packet generator 110. Herein, the generated frame may be a Base Band Packet (BBP) (otherwise referred to as a layer 1(L1) packet) including an ALP packet. Here, the terminology used to describe the transmission apparatus of fig. 12 may vary according to system design. For example, the ALP packet and the BBP packet may be referred to as a BBP packet and a baseband frame (BBF), respectively, in another system.

Specifically, the frame generator 130 arranges a plurality of ALP packets containing a TS packet or an IP packet and a header to generate the arranged ALP packets as base band packets having a size corresponding to the FEC code. The ALP packet according to the exemplary embodiment may be a TS packet, but the same procedure may be applied to various types of data as well as the TS packet.

Fig. 13 is a block diagram showing a detailed configuration of a frame generator according to an exemplary embodiment.

Referring to fig. 13, the frame generator 130 may include a baseband header generator 130-1 and a baseband packet generator (also referred to as a baseband packet builder) 130-2. In addition, the baseband packet generator 130-2 may transmit the generated baseband packet to the baseband packet scrambler 135.

The baseband header generator 130-1 may generate a header inserted into the baseband packet. Here, the header inserted into the baseband packet is referred to as a baseband header, and the baseband header includes information about the baseband packet.

Specifically, when the input stream is a TS, the baseband header generator 130-1 may generate a baseband header including information on the number of TS packets, the number of deleted null packets, and the like in the ALP packet. In addition, the baseband header generated by the baseband header generator 130-1 may include various information, and this will be described below.

In addition, the baseband packet generator 130-2 encapsulates the baseband header generated from the baseband header generator 130-1 and the ALP packet output from the packet generator 110 to generate a baseband packet.

Further, the baseband packet scrambler 135 mixes data stored in the baseband packet in a random order to generate a scrambled baseband packet before the FEC code is applied to the baseband packet. The scrambled baseband packets are transmitted through at least one PLP and signal processed. In this case, one PLP may be constructed with a baseband packet having a fixed size. In other words, for one PLP, the input stream may be encapsulated to the baseband packet.

PLP refers to signal paths that are processed independently. In other words, a corresponding service (e.g., video, extended video, audio, data stream, etc.) can be transmitted and received through a plurality of RF channels, and the PLP is a path for transmitting the service or a stream is transmitted through the path. Further, the PLP may be placed at slots (slots) distributed at certain time intervals over a plurality of RF channels or distributed at certain time intervals over one RF channel. In other words, one PLP may be transmitted while being distributed over one RF channel or a plurality of RF channels at certain time intervals.

The PLP structure is composed of an input pattern a providing one PLP and an input pattern B providing a plurality of PLPs, and particularly, when the PLP structure supports the input pattern B, the PLP structure can provide a strong specific service, and the time interleaving length is increased by distributing and transmitting one stream to obtain a time diversity gain. In addition, when only a specific stream is received, the power of the receiver may be turned off for the remaining time so as to be used at low power, and thus, the receiver is suitable for providing a portable mobile broadcasting service.

Time diversity is the following technique: when the transmitting side transmits the same signal several times at a predetermined time interval in order to reduce the degradation of the transmission quality in the mobile communication transmission path, the receiving side synthesizes the received signals again to obtain a superior transmission quality.

In addition, information that can be generally transmitted to a plurality of PLPs is transmitted through one PLP to increase transmission efficiency, and PLP0 performs such a role. When the PLP is referred to as a common PLP and PLPs other than PLP0 can be used for data transmission, these PLPs are referred to as data PLPs. When such PLPs are used, home high definition tv (hdtv) programming may be received and, in a mobile scenario, standard definition tv (sdtv) programming may be provided to the mobile device. In addition, various broadcast services can be provided to viewers through broadcasting stations or broadcast content providers, and differential broadcast services can be provided to receivers even located in edge areas where service reception is very difficult.

Meanwhile, fig. 14 is a diagram illustrating an ALP packet, a baseband packet, and a scrambled baseband packet according to an exemplary embodiment.

Referring to fig. 14, when the packet generator 110 stores at least one TS or IP packet in a payload and inserts a header to generate a plurality of ALP packets 111 and 112, the frame generator 130 packetizes the generated plurality of ALP packets 111 and 112 and inserts a baseband header to generate a plurality of

baseband packets

121 and 122. Here, the

respective baseband packets

121 and 122 may include a plurality of ALP packets, and may also include a part of the ALP packets.

Baseband packet scrambler 135 randomly scrambles the respective generated

baseband packets

121 and 122 to generate a plurality of scrambled baseband packets, e.g., scrambled baseband packet 125-1. Further, the generated scrambled baseband packet 125-1 may be transmitted to at least one PLP as described above and subjected to signal processing in order to add an FEC code.

Returning to fig. 12, the signal processor 140 may perform signal processing on the generated baseband packet, which may be a scrambled baseband packet.

Specifically, the signal processor 140 performs signal processing on the baseband packet to generate a transmission frame.

In addition, the signal processor 140 may insert signaling information into a signaling region of a frame. The signaling information may be referred to herein as an L1 signaling signal for frame synchronization. The preamble into which the L1 signaling information is inserted may include a L1 pre-signaling region and a L1 post-signaling region.

Meanwhile, although not shown, the signal processor 140 may perform functions corresponding to the BICM blocks 12000 and 12000-1 and the framing/interleaving blocks 13000 and 13000-1 shown in fig. 3A through 3C.

The transmitter 150 may transmit the signal-processed frame to a receiving device (not shown).

Specifically, the transmitter 150 may perform functions corresponding to the waveform generation blocks 14000 and 14000-1 shown in fig. 3A to 3C. In other words, the transmitter 140 performs modulation for modulating the generated frame to an RF signal, and transmits the RF signal to the receiving device.

Hereinafter, a TS packet encapsulation mechanism according to various exemplary embodiments will be described in detail with reference to the accompanying drawings. However, detailed description of portions redundant with the above portions will be omitted.

Fig. 15 is a diagram describing a TS packet encapsulation mechanism according to an exemplary embodiment.

As described above, ALP packets can transport MPEG-2TS packets without sync bytes in the payload. Fig. 15 shows an ALP packet including eight MPEG-2TS packets. The encapsulation process is described as follows:

-deleting sync bytes of MPEG-2TS packets for encapsulation. Accordingly, the length of the MPEG-2TS packet is reduced from 188 bytes to 187 bytes.

In this case, the length of the payload becomes 187 × 8-1,496 bytes.

-generating an ALP header of length 1 byte, i.e. the basic header of the ALP packet header. Here, the ALP header has the following values: packet _ type (1410) ═ 111 ', NUMTS (1420) ═ 1000 ', and AHF (1430) ═ 0 '.

In the ALP packet generated as described above, 7 bytes are saved compared to the case where eight MPEG-2TS packets are directly transmitted to the PHY layer.

Fig. 16A is a diagram describing a TS packet encapsulation mechanism according to another exemplary embodiment.

As described above, the ALP packet may be generated by deleting at least one null MPEG-2TS packet located immediately in front of the first MPEG-2TS packet encapsulated into the ALP packet, and the receiver may know the number of the deleted null MPEG-2TS packets through the header of the ALP packet. Fig. 16A shows an example of an ALP packet including six MPEG-2TS packets, in which two empty MPEG-2TS packets located immediately before the first MPEG-2TS packet in the payload are deleted. The encapsulation process is described as follows:

-deleting at least one empty packet and counting.

-deleting at least one sync byte of at least one MPEG-2TS packet for encapsulation. Accordingly, the length of the MPEG-2TS packet is reduced from 188 bytes to 187 bytes.

Six MPEG-2TS packets are grouped into the payload of an ALP packet in this case, the length of the payload becomes 187 × 6-1,122 bytes.

-generating an ALP header of length 2 bytes, i.e. the basic header of the ALP packet header. Here, the ALP header has the following values: packet _ type (1510) ═ 111 ', NUMTS (1520) ═ 0110 ', AHF (1530) ═ 1 ', HDM (1540) ═ 0 ', DNP (1550) ═ 0000010 '. In this case, AHF ═ 1' indicates that at least two consecutive empty packets located immediately before the first TS packet encapsulated into the payload are deleted.

The length of the ALP packet generated as described above is 1,124 bytes, and 380 bytes are saved compared to the case where six MPEG-2TS packets are directly transmitted to the PHY layer.

Fig. 16B is a diagram describing a decapsulating mechanism of the ALP packet shown in fig. 16A.

The receiver side decapsulation process is described as follows:

check DNP field 1550.

Check the number of TS packets in the ALP packet by using NUMTS field 1520.

-inserting a sync byte.

Generating an empty packet immediately preceding the valid TS packet group (i.e., the first TS packet) indicated by the DNP field 1550.

Fig. 17A is a diagram describing a TS packet encapsulation and TS header deletion mechanism according to another exemplary embodiment.

As described above, the ALP packet can be generated by compressing the header of the MPEG-2TS packet additionally encapsulated into the ALP packet. Fig. 17A shows an example of an ALP packet including eight MPEG-2TS packets having the same header except for a Continuity Counter (CC) field. The encapsulation process is described as follows:

eight TS packets with the same field except the CC field are grouped.

The header is reserved only for the first MPEG-2TS packet (except for the sync byte) and deleted for the other seven MPEG-2TS packets in this case the length of the payload becomes 3+184 × 8-1,475 bytes.

-generating an ALP header of length 2 bytes, i.e. the basic header of the ALP packet header. Here, the ALP header has the following values: packet _ type (1710) ═ 111 ', NUMTS (1720) ═ 0100 ', AHF (1730) ═ 1 ', HDM (1740) ═ 1 ', DNP (1750) ═ 0000010 '.

The length of the ALP packet generated as described above is 1,477 bytes, and 27 bytes are saved compared to the case where eight MPEG-2TS packets are directly transmitted to the PHY layer.

Fig. 17B is a diagram describing a decapsulation of the ALP packet and a TS header recovery mechanism shown in fig. 17A according to an exemplary embodiment.

The receiver side decapsulation process is described as follows:

the receiver side decapsulation process is described as follows:

TS header deletion is detected by reading HDM field 1740.

Check the number of TS packets in the ALP packet by using the NUMTS field 1720.

The first TS packet comprises a 3 byte header and a 184 byte payload, and the other TS packets comprise only a 184 byte payload.

-generating all TS packets by using the header of the first TS packet. In this case, consecutive CC fields are increased one after another.

-inserting a sync byte.

Fig. 18A to 18C are diagrams describing a header structure of an ALP packet according to another exemplary embodiment.

Fig. 18A is a diagram illustrating a structure of a basic header included in a header of an ALP packet according to another exemplary embodiment.

The Packet _ Type field 1810 is the same as the Packet _ Type field 7111 shown in fig. 8A.

The NPDI field 1820 indicates whether at least one empty TS packet is deleted. For example, the NPDI field 1820 is implemented as 1 bit, and a value of '1' indicates that the empty TS packet is deleted, and a value of '0' indicates that the empty TS packet is not deleted. Here, the header does not include an additional header as shown in fig. 18B and 18C.

NUMTS field 1830 is the same as NUMTS field 7112 shown in fig. 8A.

Fig. 18B and 18C illustrate the structure of an additional header included in a header of an ALP packet according to another exemplary embodiment. The extra header exists only when the value of the NPDI field 1820 shown in fig. 18A is '1', and the extra header may be referred to as an optional header according to system design.

The EXT field 1840 indicates the number of empty TS packet groups deleted. For example, the EXT field 1840 is implemented as a 1-bit field, and when the number of groups of consecutive empty TS packets deleted is at most one, the EXT field 1840 is set to '0'. In contrast, when the EXT field 1850 is set to '1', the number of groups of consecutively deleted empty TS packets is two or more, and an extension header exists.

The DNP field 1850 indicates the number of empty TS packets. For example, the DNP field 1850 may be implemented as a 7-bit field. According to an exemplary embodiment, the EXT field 1840 indicates the number of deleted empty TS packets preceding a TS packet group when the EXT field 1840 is '0', and the EXT field 1840 indicates the number of deleted empty TS packets relative to the first group of deleted consecutive empty TS packets when the EXT field 1840 is '1'. According to another exemplary embodiment, the EXT field 1840 indicates the number of deleted empty TS packets after a TS packet group when the EXT field 1840 is '0', and the EXT field 1840 indicates the number of deleted empty TS packets with respect to the first group of deleted consecutive empty TS packets when the EXT field 1840 is '1'. The EXT field 1840 may be disposed before the DNP field 1850, or vice versa, as shown in fig. 18B and 18C.

Fig. 19 is a diagram describing a TS packet encapsulation process using the header structure shown in fig. 18A to 18C according to an exemplary embodiment.

As shown in fig. 19, an ALP packet may be created in the illustrated form through a TS packet encapsulation process.

Specifically, the type field 1911 is a value indicating that a packet included in the payload of the ALP packet is a TS packet (e.g., '010'), the NPDI field 1912 is a value indicating that at least one null packet is deleted (e.g., '1'), the NUMTS field 1913 is a value indicating that the number of TS packets is 10 (e.g., '1010'), the EXT field 1914 is a value indicating that the number of groups of consecutive null TS packets deleted is two or more (e.g., '1'), and the i-th bit of the DNP indicator field 1915 indicates whether or not a null TS packet deleted after the i-th TS packet exists in the payload. This DNP indicator field structure is different from that of the DNP indicator 1011 in fig. 10B, and the structure of the DNP indicator 1011 indicates whether or not there is an empty TS packet deleted before the ith TS packet in the payload. This is because the empty TS packet immediately following the last TS packet in the payload is deleted before encapsulation, and in this case, the DNP pointer field structure in fig. 10B cannot indicate that there is a deleted empty TS packet following the last TS packet in the payload. Specifically, if the DNP indicator field 1915 is set to a value of '0000101000000000' according to the DNP indicator field structure in fig. 10B, the DNP indicator field 1915 can indicate that there is a deleted empty TS packet just before the fifth TS packet and the seventh TS packet, but cannot indicate that there is a last TS packet in the payload. The

respective DNP fields

1916, 1917, and 1918 may be set to values indicating that the number of deleted empty TS packets with respect to the deleted consecutive empty TS packet group is 2, 3, and 1, respectively (e.g., '0000010', '00000011', and '00000001').

Meanwhile, when the ALP packet is extracted at the receiver side, it is determined that the ALP packet includes the MPEG-2TS packet based on the value '010' of the type field 1911 of the ALP header. Based on the value '1' of the NPDI field 1912, the empty TS packet is deleted, and it is determined that an additional header exists. Further, it is determined that the ALP packet includes 10 valid TS packets based on the value '1010' of the NUMTS field 1913.

Further, based on the value '1' of the EXT field 1914, two or more empty TS packet groups in the current ALP packet are deleted and it is determined that the extension header exists.

It is determined that the first empty TS packet group includes two empty TS packets based on the value '0000010' of the DNP 1 field 1916, and it is determined that empty TS packet groups exist respectively after the fourth TS packet, the sixth TS packet, and the tenth TS packet based on the value of the DNP indicator field 1915. Further, it is determined that the second and third empty TS packet groups include three empty TS packets and one empty TS packet, respectively, by using the value '00000011' of the DNP 2 field 1917 and the value '00000001' of the DNP 3 field 1918.

Based on the determination result, four TS packets of the payload are output, then two null TS packets are output, two TS packets among remaining TS packets of the payload are output, then three null TS packets are output, and four remaining TS packets of the payload are output, then one null TS packet is output to decapsulate the ALP packet.

Fig. 20A and 20B are diagrams describing an ALP packet header structure according to another exemplary embodiment.

The configuration shown in fig. 20A and 20B shows an additional header structure according to another exemplary embodiment, and the configuration of the basic header may be the same as the basic header.

The EXT field 2010 indicates the number of empty TS packet groups deleted. For example, the EXT field 2010 is implemented as a 1-bit field, and when the number of groups of consecutive empty TS packets deleted is at most one, the corresponding field is set to '0'. In contrast, when the EXT field 2010 is set to '1', the number of groups of consecutive empty TS packets deleted is two or more, and an extension header exists.

The DNP field 2020 indicates the number of empty TS packets deleted before the TS packet group. For example, DNP field 2020 may be implemented as a 7-bit field. According to an example embodiment, the DNP field 2020 may only exist when the EXT field 2010 is '0'. According to another exemplary embodiment, the DNP field 1850 indicates the number of empty TS packets deleted after a TS packet group.

The DNPG field 2025 indicates the number of empty TS packet groups deleted. For example, the DNP field 2025 may be implemented as a 7-bit field. The DNPG field 2025 may exist only when the EXT field 2010 is '1'.

Meanwhile, in the last TS packet of each TS packet group in which an empty TS packet group after the TS packet group is deleted, a Transmission Error Indicator (TEI) field value may be set to 1.

Fig. 21 is a diagram describing a TS packet encapsulation process using the header structure shown in fig. 20A and 20B according to an exemplary embodiment.

As shown in fig. 21, an ALP packet can be created in the illustrated form through a TS packet encapsulation process.

Specifically, the type field 2111 is a value (e.g., ' 010 ') indicating that a packet included in the payload of the ALP packet is a TS packet, the NPDI field 2112 is a value (e.g., ' 1 ') indicating that at least one null packet is deleted, the NUMTS field 2113 is a value (e.g., ' 1010 ') indicating that the number of TS packets is 10, the EXT field 2114 is a value (e.g., ' 1 ') indicating that the number of groups of consecutive null TS packets deleted is two or more, and the ith bit of the DNPG field 2115 is a value (e.g., ' 000011 ') indicating that three null TS packet groups in the ALP packet are deleted, and the

corresponding DNP fields

2116, 2117, and 2118 may be set to values (e.g., ' 0000, ' 010 ', ' 00000011 ', and ' 00000001 ') indicating that the number of null TS packets deleted with respect to the corresponding deleted consecutive null TS packet groups is 2, 3, and 1, respectively.

Meanwhile, when the ALP packet is extracted at the receiver side, it is determined that the current ALP packet includes the MPEG-2TS packet based on the value '010' of the type field 2111 of the ALP header. It is determined that the empty TS packet is deleted based on the value '1' of the NPDI field 2112, and it is determined that an additional header exists. Further, it is determined that the current ALP packet includes 10 valid TS packets based on the value '1010' of the NUMTS field 2113.

Further, two or more empty TS packet groups in the current ALP packet are deleted based on the value '1' of the EXT field 2114, and it is determined that the extension header exists and then 7 bits are the DNPG field.

It is determined that there are three groups of deleted empty TS packets based on the value '0000011' of the DNPG field 2115.

It is determined that the first null TS packet group includes two null TS packets based on the value '0000010' of the DNP 1 field 2116, and it is determined that the second and third null TS packet groups include three and one null TS packet by using the value '00000011' of the DNP 2 field 1917 and the value '00000001' of the DNP 3 field 1918, respectively.

Further, by checking the TEI field at the time of outputting each TS packet, two null TS packets are output after the first packet whose TEI field value is 1 of the TS packet, three null TS packets are output after the second packet whose TEI field value is 1 of the TS packet, and one null TS packet is output after the first packet whose TEI field value is 1 of the TS packet, so as to decapsulate the ALP packet.

Fig. 22 is a diagram describing a TS packet encapsulation mechanism according to another exemplary embodiment.

As shown in fig. 22, a separate DNP field is not used in the header and

DNP values

2241, 2242, and 2243 may be recorded in locations in the payload where the corresponding empty

TS packet groups

2231, 2232, and 2233 are deleted. In this case, the base header may similarly include TYPE field 2211, NPDI field 2212, and NUMTS field 2213, and the additional header may include only EXT field 2114 and DNPG field 2115. However, in some cases, the DNPG field 2115 may be omitted.

Meanwhile, when the exemplary embodiment is used in a system, the EXT field is extended to an appropriate number of bits (e.g., 2 bits) to indicate which method is used.

Fig. 23 is a flowchart describing a signal processing method of a transmission apparatus according to an exemplary embodiment.

According to the signal processing method of the transmission apparatus shown in fig. 23, a packet including a header and a payload corresponding to an input stream, i.e., an ALP packet, is first generated (S2310). The base header constituting the header may include a first field indicating a packet type of the input stream, and when the first field is set to a value indicating that the packet type of the input stream is a TS packet, the base header may include a second field indicating the number of TS packets included in the payload and a third field set to a first value indicating that there is no additional header or a second value indicating that there is an additional header, and when the third field is set to the second value, the additional header includes a fourth field indicating the number of deleted null packets with respect to each of at least one TS packet group consisting of consecutive TS packets. The empty packet deleted with respect to each TS packet group is a preceding empty TS packet immediately preceding the first TS packet included in each TS packet group among the plurality of packets included in the input stream.

Subsequently, a frame including the generated packet, i.e., a baseband packet, is generated (S2320).

The generated baseband packet is subjected to signal processing (S2330).

After that, the signal-processed frame is transmitted (S2340). Herein, the signal-processed frame may become a transmission frame.

Fig. 24A is a block diagram showing a configuration of a reception apparatus according to an exemplary embodiment.

Referring to fig. 24A, the receiving apparatus 200 includes a receiver 210 and a signal processor 220.

The receiving device 200 may be implemented to receive data from a transmitting device that maps data included in an input stream to at least one signal processing path and transmits the mapped data.

The receiver 210 receives a frame including data mapped to at least one signal processing path. In particular, the receiver 210 may receive a stream including signaling information and data mapped to at least one signal processing path. Herein, the signaling information may include information on an input type of an input stream input into the transmission apparatus and information on a data type mapped to the at least one signal processing path. In this context, information about the input type of an input stream may indicate whether all signal processing paths in a frame are of the same input type. In addition, since the detailed information included in the signaling information has already been described, the detailed description will be omitted.

The signal processor 220 extracts signaling information from the received frame. Specifically, the signal processor 220 may acquire various information on the corresponding PLPs included in the L1 front signaling region and the L1 rear signaling region by extracting the L1 signaling and decoding. Further, the signal processor 230 performs signal processing on the frame based on the extracted signaling information. For example, in signal processing, demodulation, frame de-constructor, BICM decoding, and input inverse processing procedures may be performed.

Specifically, the signal processor 220 performs signal processing on a transmission frame received by the receiver 210 to generate a baseband packet, and extracts header information from an ALP packet included in the generated baseband packet.

Further, the signal processor 220 performs signal processing on the payload data included in the ALP packet based on the extracted header information to restore the stream, i.e., the input stream, which is first input into the transmission apparatus 100. Herein, the extracted header information includes a field indicating a payload data type and a field indicating whether the ALP packet transmits a complete input packet.

Fig. 24B is a block diagram illustrating in detail a signal processor according to an exemplary embodiment.

Referring to fig. 24B, the signal processor includes a demodulator 221, a decoder 222, and a stream generator 223.

The demodulator 221 performs demodulation according to the OFDM parameter from the received RF signal to perform synchronization detection, and when synchronization is detected, identifies whether the currently received frame includes required service data from signaling information stored in the synchronization region. For example, it may be identified whether a moving frame is received or whether a fixed frame is received.

In this case, when the OFDM parameters for the signaling region and the data region are not predetermined, the OFDM parameters for the signaling region and the data region stored in the synchronization region are acquired to demodulate OFDM parameter information for the signaling region and the data region immediately after the synchronization region.

The decoder 222 decodes the required data. In this case, the decoder 222 may acquire and decode parameters including an FEC scheme, a modulation scheme, etc. for data stored in each data region by using the signaling information. Further, the decoder 223 may calculate the position of the acquired data based on the data information included in the header. In other words, it is possible to calculate where in the frame the required PLP is transmitted.

The stream generator 223 processes the baseband packet received from the decoder 222 to generate data to be serviced.

As one example, the stream generator 223 may generate an ALP packet from the error-corrected baseband packet based on various information. In particular, the stream generator 223 may include a de-jitter buffer, and the de-jitter buffer may regenerate the precise timing for recovering the output stream based on various information. Accordingly, a delay of synchronization between a plurality of PLPs can be compensated.

Fig. 25 is a block diagram illustrating a configuration of a receiver according to an exemplary embodiment.

Referring to fig. 25, the receiver 2100 may include a controller 2110, an RF receiver 2120, a demodulator 2130, and a service reproducer 2140.

The controller 2110 determines an RF channel and a PLP for transmitting the selected service. In this case, the RF channel may be designated as a center frequency and a bandwidth, and the PLP may be designated as a PLP Identifier (ID). A specific service may be transmitted through one or more PLPs belonging to one or more RF channels for each component constituting the service, but hereinafter, for convenience of description, it is assumed that all data required to reproduce one service is transmitted to one PLP, which is transmitted to one RF channel. In other words, the service has a unique data acquisition path for reproducing the service, and the data acquisition path is designated as an RF channel and a PLP.

The RF receiver 2120 detects an RF signal in an RF channel selected by the controller 2110 and transfers an OFDM symbol extracted by signal-processing the RF signal to the demodulator 2130. Here, the signal processing may include synchronization, channel estimation, and equalization, and information for the signal processing is a value predetermined by the transmitter and the receiver or included in a specific OFDM symbol predetermined among OFDM symbols to be transmitted in the receiver according to system design.

The demodulator 2130 performs signal processing on the OFDM symbols to extract user packets and transfers the extracted user packets to the service reproducer 2140, and the service reproducer 2140 reproduces and outputs a service selected by the user by using the user packets. In this case, the format of the user packet may vary according to the implementation of the service, and as one example, a TS packet or an IPv4 packet is provided.

Fig. 26 is a block diagram illustrating the demodulator shown in fig. 25 in more detail according to an exemplary embodiment.

Referring to fig. 26, the demodulator 2130 may be configured to include a frame demapper 2131, a BICM decoder 2132 for L1 signaling, a controller 2133, a BICM decoder 2134, and an output processor 2135.

The frame demapper 2131 selects OFDM cells (which constitute an FEC block belonging to a selected PLP in a frame constituted by OFDM symbols) based on control information transmitted in the controller 2133 and transmits the selected OFDM cells to the BICM decoder 2134, and additionally selects OFDM cells corresponding to one or more FEC blocks included in the L1 signaling and transmits the selected OFDM cells to the BICM decoder 2132 for the L1 signaling.

The BICM decoder 2132 for L1 signaling signal-processes the OFDM cells corresponding to the FEC blocks included in the L1 signaling to extract L1 signaling bits, and transfers the extracted L1 signaling bits to the controller 2133. In this case, the signal processing may include a process of extracting log-likelihood ratio (LLR) values to decode low-density parity-check (LDPC) codes in the OFDM cell, and a process of decoding the LDPC codes by using the extracted LLR values.

The controller 2133 extracts an L1 signaling table from the L1 signaling bits and controls the operations of the frame demapper 2131, the BICM decoder 2134, and the output processor 2135 by using the values of the L1 signaling table. In fig. 22, the BICM decoder 2132 for L1 signaling is shown without using control information of the controller 2133 for convenience of description. However, when the L2 signaling has a layered structure similar to the L1-front structure and the L1-rear structure, the BICM decoder 2132 for the L1 signaling may be composed of one or more BICM decoding blocks, and the operation of the BICM decoding blocks and the frame demapper 2131 may be obviously controlled by the L1 signaling information of a higher layer.

The BICM decoder 2134 performs signal processing on the OFDM cells constituting the FEC block belonging to the selected PLP to extract a baseband packet, and transfers the baseband packet to the output processor 2135. The signal processing may include a process of extracting LLR values for encoding and decoding the LDPC code in the OFDM cell, and a process of decoding the LDPC code by using the extracted LLR values, and may be performed based on control information transmitted in the controller 2133.

The output processor 2135 performs signal processing on the baseband packet to extract a user packet, and transfers the extracted user packet to the service reproducer 2140. In this case, signal processing may be performed based on a control signal transmitted in the controller 2133.

It is assumed that service information of all selectable services is acquired in the initial scan (S2700) before the user selects the service (S2710). Here, the service information may include information on an RF channel and a PLP transmitted in the current broadcasting system for data required for reproducing a specific service. One example of the service information includes program specific information/service information (PSI/SI) of MPEG2-TS, and can be generally acquired through L2 signaling and higher layer signaling.

When the user selects a service (S2710), the receiver changes the current frequency to a frequency used to transmit the selected service (S2720) and performs RF signal detection (S2730). The service information may be used during a procedure of changing a current frequency to a frequency used to transmit the selected service (S2720).

When the RF signal is detected, the receiver performs an L1 signaling extraction operation from the detected RF signal (S2740). Thereafter, the receiver selects a PLP for transmitting the service selected by using the L1 signaling extracted in the previous procedure (S2750), and extracts a baseband packet from the selected PLP (S2760). The service information may be used during a process of selecting a PLP for transmitting the selected service (S2750).

Further, the process of extracting the baseband packet (S2760) may include a process of selecting an OFDM cell belonging to the PLP by demapping the transmission frame, extracting LLR values for encoding/decoding the LDPC code in the OFDM cell, and a process of decoding the LDPC code by using the extracted LLR values.

The receiver performs ALP packet extraction from the base band packet extracted by using header information of the extracted base band packet (S2770), and performs user packet extraction from the ALP packet extracted by using header information of the ALP packet extracted thereafter (S2780). The extracted user pack is used to reproduce the selected service (S2790). In the ALP packet extraction (S2770) and user packet extraction (S2780) processes, the L1 signaling information acquired in the L1 signaling extraction (S2740) step may be used. In this case, the process of extracting the user packet from the ALP packet (restoring the null TS packet and inserting the TS sync byte) is similar to the above-described process.

According to various exemplary embodiments as described above, various types of data can be mapped to a transmittable physical layer on the transmitter side, and data processing efficiency can be improved. In addition, packets are filtered in the link layer on the receiver side to increase data processing efficiency.

According to exemplary embodiments, at least one of the components, elements, modules or units represented by the blocks in the figures may be embodied as various numbers of hardware, software and/or firmware structures performing the respective functions described above. For example, at least one of these components, elements, modules or units may use a direct current circuit structure, such as a memory, a process, logic, a look-up table, or the like, that may perform a corresponding function by controlling one or more microprocessors or other control devices. Furthermore, at least one of these components, elements, modules or units may be embodied by a module, program, or portion of code, which contains one or more executable instructions for performing specific logical functions, and executed by one or more microprocessors or other control devices. Furthermore, at least one of these components, elements, modules or units may further include a processor, such as a central control unit (CPU), microprocessor, or the like, that performs a corresponding function. Two or more of these components, elements, modules or units may be combined into a single component, element, module or unit that performs all of the operations or functions of the two or more components, elements, modules or units combined. Furthermore, at least part of the functionality of at least one of these components, elements, modules or units may be performed by another one of these components, elements, modules or units. In addition, although a bus is not shown in the above block diagrams, communication between components, elements, modules, or units may be performed through the bus. The functional aspects of the exemplary embodiments described above may be implemented in algorithms executing on one or more processors. Further, the components, elements, modules or units represented by the blocks or process steps may use any number of the related art techniques for electronic device configuration, signal processing and/or control, data processing, and the like.

The above-described methods and operations or steps of the methods may also be embodied as computer readable codes in a computer readable recording medium. The computer readable recording medium is any data storage device that can store data which can be read by a computer system. Examples of the computer readable recording medium may include read-only memory (ROM), random-access memory (RAM), CD-ROMs, magnetic tapes, floppy disks, optical data storage devices, and carrier waves (such as data transmission through the internet). The computer readable recording medium can also be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. In addition, functional programs, codes, and code segments for implementing the exemplary embodiments can be easily analyzed by programmers in the field to which the present disclosure is applied.

Further, it can be seen that the apparatus and method according to the exemplary embodiments can be implemented by hardware, software, or a combination of hardware and software. Whether the predetermined software is erasable or rewritable, the predetermined software may be stored in a volatile or nonvolatile storage device (such as a ROM), a memory (such as a RAM, a memory chip, a device, or an integrated circuit), or a storage medium (such as a CD, a DVD, a magnetic disk, or a magnetic tape), which can optically or magnetically record data and can be read by a machine (e.g., a computer) at the same time. The above-described method or the operations of the method may be implemented by a computer or a portable terminal including a controller and a memory, and it can be seen that the memory is one example of a program including instructions implementing the exemplary embodiments or a machine-readable storage medium suitable for storing the program.

Accordingly, exemplary embodiments include a program including code for implementing the apparatus and methods described in any claims of the specification, and a machine (computer) -readable storage medium storing the program. Further, the program may be carried electronically via any medium, such as a communication signal transmitted over a wired or wireless connection, and the disclosure includes equivalents of the medium as appropriate.

Further, the apparatus according to the exemplary embodiments may receive and store a program from a program providing device connected using a wired or wireless method. The program providing apparatus may include: the content protection system includes a program including instructions allowing a program processing device to execute a predetermined content protection method, a memory for storing information required for the content protection method, a communicator for performing wired or wireless communication with a graphic processing device, and a controller for transmitting the corresponding program to a transmission/reception device automatically or according to a request of the graphic processing device.

Meanwhile, detailed exemplary embodiments have been described in the detailed description, but various modifications may be made without departing from the scope. Accordingly, the scope should not be limited by the exemplary embodiments, but by the appended claims and equivalents of the appended claims.

Claims

1. A transmission apparatus comprising:

a packet generator receiving a plurality of Transport Stream (TS) packets and generating packets including a header and a payload from an input stream including the plurality of Transport Stream (TS) packets; and

a transmitter for transmitting the generated packet,

wherein the header includes a first field, a second field, and a third field,

wherein the plurality of TS packets have at least one of an empty TS packet group and a non-empty TS packet group,

wherein the first field includes a value indicating a packet type of the plurality of TS packets,

wherein the second field includes a value indicating the number of deleted empty TS packet groups,

wherein the third field includes a value indicating the number of deleted empty TS packets included in the deleted empty TS packet group,

wherein the number of the deleted empty TS packets is the number of empty TS packets included in an empty TS packet group preceding a non-empty TS packet group, and

wherein if the second field includes a first value, the third field is a value indicating the number of deleted empty TS packets in a first empty TS packet group included among the deleted empty TS packet groups.

2. The transmission apparatus according to claim 1, wherein each of the TS packets includes synchronization information which is removed to form the packet generated by the packet generator when the TS packet is encapsulated in a payload of the packet generated by the packet generator.

3. The transmission device of claim 1, wherein the packet generated by the packet generator is a link layer protocol packet to be mapped to a physical layer prior to transmission out of the transmission device.

4. A signal processing method of a transmission apparatus, comprising:

receiving a plurality of Transport Stream (TS) packets and generating packets including a header and a payload from an input stream including the plurality of Transport Stream (TS) packets; and

the generated packet is transmitted to the mobile station,

wherein the header includes a first field, a second field, and a third field,