JPH099156A - Program changeover method in digital satellite broadcast and digital satellite broadcast receiver - Google Patents

Abstract

PURPOSE: To relieve a sense of incongruity provided to a viewer by discriminating whether or not a number of an identified transponder is identical to a number of a transponder making reception and switching the reception to a transponder with the identified number so as to decrease a time difference between the revision of a program number attended with changeover of transponders and the revision of a program number not attended with the changeover. CONSTITUTION: A transmitter side uses part of a program number for a number of a transponder sending the program with the program number, a receiver side identifies a program of a transponder sending the program based on the revised program number in the case of revising the program number under the control of a control section 108 so as to discriminate whether or not the number of the identified transponder is identical to the number of the transponder making reception and the reception is switched to a transponder with an identified number when being discriminated not identical.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiver for digital satellite broadcasting and a program switching method for digital satellite broadcasting.

[0002]

2. Description of the Related Art In recent years, standardization work of digital broadcasting has been actively carried out in various countries. ATV (A
DVV (Digita) in Europe
A broadcasting system called Video Broadcasting) has been proposed, and it is aimed at practical use in a few years. In Japan, the standardization work of digital satellite broadcasting using communication satellites is in progress. The base of these broadcasting systems is M
It is a PEG2 standard, and MPEG2 became an international standard in November 1994.

In digital broadcasting, the number of channels can be several times that of the current broadcasting, but as the number of channels increases, it becomes necessary to devise a method for channel selection and program selection. That is, since a multi-program-supported transport stream transmits a large number of individual video and audio streams, it is necessary to have information on which program is selected and which packet is extracted from the plurality of programs. Become. Therefore, in MPEG2, PSI (Program Specific Information) is used as transmission control information necessary for program reception.
Are transmitted by a plurality of additional information tables called. MPE
There are the following three types of PSI tables defined in G2.

PAT (Program Association Table): Program association table PMT (Program Map Table): Program map table CAT (Conditional Access Table): Conditional access table PAT is a program number (program number) and a packet ID indicating the PMT It is a table showing the relationship of (PMT_PID), where PMT is a program number and components constituting the program (video, audio, clock reference)
5 is a table showing a relationship between PIDs (elementary PIDs) of the above. Here, the PID is a number for identifying a packet and is also called a packet identifier. The PID assigned to a video packet and an audio packet is an elementary PI.
It is called D.

As described above, the PAT and the PMT are divided into indirect descriptions. If only one table is used to describe everything, the table becomes too large, the memory for storing the table becomes large, and it takes time to access. This is because of this.

The CAT is used for pay broadcasting, and is an attached table for the authorized user to decode and reproduce the scrambled stream.
It is a table which shows the relationship between PID and an EMM (Entitled Management Message) stream.

Further, although not specified in MPEG2, NIT (Nework Information Table) is specified in European DVB as a table necessary for receiving a program. The NIT includes a network name and transmission parameters, and this NIT is a table showing a relationship between a program number and a transport stream ID individually corresponding to a plurality of satellite transponders (repeaters). It is possible to know the correspondence between the program number and the number (transport stream ID) of the transponder transmitting the program from this table.

In MPEG2, user-defined data whose contents are not defined is called private data, and section-type data among them is called private section.

The details of the above terms are defined in ISO
/ IEC13818-1 November 1994
It is described in.

Next, the flow of processing in the receiving device when changing the program (program) number, which is currently under consideration, will be described with reference to FIG. Note that FIG. 9 shows a case where the transmission path is a satellite.

It is now assumed that the program number = x is being received and that the signal from the transponder with the transponder number n0 of the plurality of transponders mounted on the satellite is being received (step n1). During this reception,
The above-mentioned NIT, PAT, PMT, etc. are received and stored in the memory.

Here, the program number (prog
ram number) is the one that corresponds to the channel number in conventional analog broadcasting, and it should be noted that it does not correspond to individual programs such as news and sports relay.

Next, when the viewer changes the program number to y (step n2), the transponder n currently being received is received.
It is searched whether or not the program number = y is included in the PAT of 0, that is, whether or not the program with the program number = y is transmitted from the transponder n0 (step n).
3). Here, the transponder numbers individually correspond to the transport stream IDs.

When the program number = y is included in the PAT of the transponder n0, the packet identifier (PMT_PID) of the PMT corresponding to the program number = y is found (step n4), and the PMT of the packet identifier is found.
Above, the elementary PID (E
L The PID) is found (step n5), the video packet, audio packet, and clock reference (PCR) of the elementary PID are extracted, and video decoding, audio decoding, and clock reproduction are performed (step n6).

At step n3, if the PAT of the transponder n0 currently being received does not include the program number = y, the program number = y is transmitted by the NIT at which transponder number (transport stream ID). Search whether there is a transponder with a transponder number n (step n
7) The reception frequency is switched to the frequency of the transponder n to receive PAT, PMT, etc. (step n
8) Go to step n4, that is, find the PMT packet identifier (PMT_PID) corresponding to the program number = y in the PAT of transponder n (step n4), and on the PMT having the packet identifier,
Elementary PID (EL corresponding to program number = y P
ID) is found (step n5), the video packet, audio packet, and clock reference (PCR) of the elementary PID are extracted, and video decoding, audio decoding, and clock reproduction are performed (step n6).

The above is the flow of the process at the time of changing the program that is currently under study.

[0017]

However, in such a program number change, the program number to be switched is
The time taken to obtain the PMT packet identifier (PMT_PID) varies considerably depending on whether it is included in the PAT before switching, that is, whether the processes of steps n7 and n8 described above are performed, and the viewer feels uncomfortable. There is a difficulty in giving.

The present invention has been made in view of the above technical problems, and it is possible to make a time difference between a change of a program number accompanied by switching of a transponder and a change of a program number not accompanied by switching of a transponder. The purpose is to reduce the discomfort that the viewer feels uncomfortable.

[0019]

In order to achieve the above-mentioned object, the present invention is configured as follows.

That is, in the program switching method for digital satellite broadcasting according to the present invention, on the transmitting side, a part of the program number is used as the transponder number for transmitting the program of the program number, and on the receiving side, the program number is changed. In this case, the number of the transponder transmitting the program is identified from the changed program number, and it is determined whether the identified transponder number is the same as the receiving transponder number. When it is determined that the reception is switched to the transponder having the identified transponder number.

Program in digital satellite broadcasting of the present invention
The switching method is that part of the program number is
The number of the transponder that transmits the program with the group number
When changing the program number on the receiving side, the change setting is
The number of the transponder that sends the program from the program number
Identifying the transponder and the identified transponder
Is the number the same as the receiving transponder number?
The step of determining whether or not it is determined that it is not the same
The transponder number identified above.
The step to switch to reception to the ponder and the change is set.
Program association table (Program Associatio
n Table), the program map table pattern corresponding to the program number.
Ket identifier (PMT PID) extraction step
And the number with the extracted program map table packet identifier
In the Program Map Table, set the above changes.
Elementary packet identifier corresponding to the specified program number
(EL PID) extraction step, and the extracted
A packet with an elementary packet identifier is
With the steps of extracting from the sport stream
You.

In the program switching method for digital satellite broadcasting of the present invention, on the transmitting side, a part of the program number is used as the number of the transponder that transmits the program of the program number, and the transport stream of each transponder contains all the transponders. When the program linkage table is transmitted as private data and the receiving side changes the program number, the step of identifying the transponder number that transmits the program from the changed set program number, and the number of the identified transponder Is the same as the number of the transponder being received, and when it is determined that it is the same, the program number corresponding to the program number is included in the program linkage table containing the changed program number. If it is determined that the step is not the same as the step of extracting the program map table packet identifier, In parallel with switching the reception to the transponder of the specified transponder number, extracting a program map table packet identifier corresponding to the changed program number from the program association table sent as the private data, A step of extracting an elementary packet identifier corresponding to the changed program number in the program map table having the extracted program map table packet identifier, and a packet having the extracted elementary packet identifier. Extracting from the transport stream.

In the program switching method for digital satellite broadcasting of the present invention, on the transmitting side, a part of the program number is used as the number of the transponder that transmits the program of the program number, and the transport stream of each transponder contains all the transponders. When the program linkage table is transmitted as private data and the receiving side changes the program number, the step of identifying the transponder number that transmits the program from the changed set program number, and the number of the identified transponder Is the same as the number of the transponder that is being received, and if the transponder of the identified transponder number satisfies the predetermined condition when it is determined that they are not the same, The second determination step for determining whether or not the predetermined condition is not satisfied is determined. At the time, the step of switching reception to the transponder of the identified transponder number, and the program map table packet identifier corresponding to the program number are extracted in the program linkage table including the changed program number. And, when it is determined that the predetermined condition is satisfied, the reception is switched to the transponder of the identified transponder number, and in parallel, the change is made from the program linkage table transmitted as the private data. A step of extracting a program map table packet identifier corresponding to the set program number; and a program map table having the extracted program map table packet identifier, the elementary packet identifier corresponding to the changed set program number The step of extracting and the extracted elementary packet identifier And a step of extracting from the transport stream packets.

The digital satellite broadcast receiving apparatus of the present invention is an apparatus for receiving a digital satellite broadcast in which a part of the program number is transmitted as a transponder number for transmitting the program of the program number, and is changed and set. The identification means for identifying the transponder number transmitting the program from the program number, and the determination means for determining whether or not the identified transponder number is the same as the number of the transponder being received. When it is determined that they are not the same, a switching unit that switches reception to the transponder of the identified transponder number is provided.

[0025]

According to the present invention, a part of the program number is used as the transponder number, and when the program number is changed on the receiving side, the transponder number for transmitting the program from the changed set program number is set. Since the identification is performed, when the program number is changed accompanying the switching of the transponder, it is not necessary to search the number of the transponder to which the changed program number belongs, and the time required to change the program number is shortened.

Further, according to the program switching method for digital satellite broadcasting of the present invention, the transmitting side sends the program linkage table of all transponders as private data to the transport stream of each transponder, and the receiving side changes and sets it. When the transponder number corresponding to the transmitted program number is not the same as the transponder number being received, the program number changed and set from the program linkage table sent as the private data in parallel with the switching of the transponder reception. Since the program map table packet identifier corresponding to the above is extracted, that is, the transponder switching and the program map table packet identifier extraction are performed in parallel, the time required to change the program number accompanying the transponder switching is further shortened.

[0027]

Embodiments of the present invention will now be described in detail with reference to the drawings.

(Embodiment 1) First, a first embodiment of the present invention will be described.

FIG. 1 is a diagram showing the configuration of a digital satellite broadcast receiving apparatus common to each of the first to sixth embodiments of the present invention.

In the figure, reference numeral 101 denotes a receiving unit, which receives radio waves (bit stream) from a broadcasting satellite or a communication satellite. Reference numeral 102 denotes a reception transponder switching unit as switching means, which switches the transponder of the satellite to be received. A demodulation unit 103 demodulates the received bit stream. A channel decoding unit 104 reproduces a transport packet by performing Viterbi decoding, deinterleaving, error correction, and the like. Reference numeral 105 denotes a transport stream separation unit, which is a PID
D), transport packets are separated based on TID (table ID). Reference numeral 106 denotes a table storage unit, which is the P such as NIT, PAT, PMT described above.
It stores SI (Program Specific Information) and a private section. A data stream storage unit 107 stores a video stream and an audio stream. A clock reproduction unit 109 reproduces the system clock based on the clock reference included in the transport stream. 108
Is a control unit having functions as an identification unit and a determination unit, and includes a reception transponder switching unit 102 and a demodulation unit 10.
3, the channel decoding unit 104, the transport stream separation unit 105, the table storage unit 106, the data stream storage unit 107, and the clock reproduction unit 109.

The operation of the first embodiment of the program switching method in the digital satellite broadcasting receiving apparatus configured as described above will be described.

In this embodiment, the transmitting side is devised as described below regarding the allocation of the program number and the transport stream ID. That is, as shown in FIG. 2, of the 16-bit program number (program_number) assigned by MPEG2, for example, the upper 4 bits represent the number of the transponder that transmits the program of that program number. There is.

Further, the transponder number and the transport stream ID individually correspond to each other as shown in Table 1, for example.

[0034]

[Table 1]

Further, the transport stream ID and the program number individually corresponding to each transponder correspond, for example, as shown in Table 2, and this relationship is expressed in the above-mentioned NIT (Newtwork Information Table). Described.

[0036]

[Table 2]

Next, the processing at the time of changing the program in this embodiment will be described based on the flowchart of FIG.

Currently, the program number (program_number) x = 0
It is assumed that x0001 (hexadecimal expression) is being received (step n10).

The operation of the receiving apparatus at this time will be described with reference to FIG. The demodulation unit 103 demodulates the bit stream of transponder number 0 from Table 1 and Table 2,
The transport stream separation unit 105 stores a PAT (Program Association Table) with a transponder number 0 in the table storage unit 106. More specifically, a unique PID (= 0x00) is assigned to the PAT (MPEG2 standard), and the transport stream separation unit 105 recognizes the PID and identifies the PAT in an area of the table storage unit 106. To store. This P
The AT has a PMT (Program Map) corresponding to the program number x.
Table) PID (PMT_PID) is described.

Transport stream separation section 105
Recognizes this PMT_PID and stores the PMT in a certain area other than the area in which the PAT of the table storage unit 106 is stored. The control unit 108 determines the storage areas of the PAT and PMT in the table storage unit 106. The control unit 108 reads the elementary PID (video stream, audio stream) corresponding to the program number x described in the PMT, and the transport stream separating unit 105 extracts the packet having the elementary PID from the transport stream. Set. Further, the control unit 108 reads the PCR PID (clock-based PID) corresponding to the program number x described in the PMT, and the transport stream separation unit 105 reads the PCR-based (PCR: Program Clock Refereer).
nce) is set to be extracted. The video packets and audio packets extracted by the transport stream separation unit 105 are temporarily stored in the data stream storage unit 10.
7 and then output to the video decoder and audio decoder. Transport stream separation unit 1
The clock reference (PCR) extracted in 05 is used as a reference for system clock recovery in the clock recovery unit 109.

Referring again to FIG. 3, the viewer changes from x to y.
When the program number is changed to (≠ x) and the program number y is set (step n11), the control unit 108 looks at the upper 4 bits of the program number y and determines which transponder, that is, the transport stream ID. Is immediately identified (step n12), and it is determined whether or not it is the same as the transport stream ID of the program number x, that is, the number of the transponder being received (step n13). If not, the receiving transponder switching unit 102 is controlled to switch the receiving transponder (step n14).

When the reception is switched to the transponder to which the program number y belongs, the control unit 108 stores the PAT having the new transport stream ID in the table storage unit 10.
6 is stored. Then, the PMT_PID of the program number y is extracted from the PAT and the PM having this PMT_PID is extracted.
Store T in the table storage unit 106 (step n1).
5). Program number = y on the PMT of the packet identifier
Elementary PID (EL The PID) is found (step n16), the video packet, audio packet and clock reference (PCR) of the elementary PID are extracted, and video decoding, audio decoding and clock reproduction are performed (step n1).
7).

In the conventional example of FIG. 9, how to assign a program number is
Although it is irrelevant to the transponder number, in this embodiment, by assigning the transponder number to the upper 4 bits of the program number, when the program number is changed accompanying the switching of the transponder, the changed program number in the NIT is determined. Transponder number (Transport Stream I
It is not necessary to perform a search as to whether it belongs to D), and as a result, compared to the conventional example, the time required to change the program number accompanying the switching of the transponder is equal to the search time of the transponder corresponding to the program number in the NIT. As a result, the time difference between the time required to change the program number that involves switching the transponder and the time required to change the program number that does not involve switching the transponder can be reduced, making viewers feel uncomfortable. It can be reduced.

(Second Embodiment) Next, a second embodiment of the present invention will be described.

The basic construction of the second embodiment is similar to that of the first embodiment shown in FIG.

Also in this embodiment, as in the first embodiment, the transponder number is assigned to the upper 4 bits of the program number, and the relationship between the transponder number and the transport stream ID is set in the same manner as in the first embodiment. As shown in Table 1, the relationship between the transport stream ID and the program number is shown in Table 2.

In this embodiment, the PATs (up to 16 in this case) of all transponders are transmitted from the transmitting side in the MPEG2 private section. That is, no matter which transponder is received, the PATs of all transponders can be received.

Here, sectio of the private section
n_syntax_indicator is set to 1 and table_id_exten
Describe the transport stream ID in sion, and privat
In e_data_byte, the relation between the program number and PID similar to PAT is described.

Next, the processing when changing the program number in this embodiment will be explained based on the flow chart of FIG.

In this embodiment, even when the program number x is being received (step n20), the PATs of all transponders other than the transponder to which the program number x belongs are also received as private sections, as shown in FIG. In the receiving device, the private sections in which these PATs are described are stored in the area determined by the control unit 108 of the table storage unit 106. The private section is identified by the transport stream ID described in table_id_extension.

When the viewer changes the program number from x to y (≠ x) and sets the program number y (step n21),
The control unit 108 immediately identifies which transponder, that is, the transport stream ID, by looking at the upper 4 bits of the program number y (step n22),
It is determined whether it is the same as the transport stream ID of the program number x (step n23), and if it is not the same, the reception transponder switching unit 102 is controlled to switch the reception of the transponder (step n2).
4). In this embodiment, the control unit 108 reads out the PAT having the transport stream ID (corresponding to the transponder number) of the program number y from the table storage unit 106 in parallel with the switching of the reception of the transponder, and assigns it to the program number y. The corresponding PMT_PID is extracted (step n24). The PAT in this case is sent from the transmission side as a private section, and the table storage unit 1
It is stored in 06.

Transponder of program number y and program number x
If the transponders are the same and it is not necessary to switch the transponder reception, the control unit 108 determines that the program number x
PMT_PID is extracted by the PAT (not the private section) of the transponder (step n2)
5). The process after the control unit 108 extracts the PMT_PID is the same as that in the first embodiment (steps n26, n).
27).

In this embodiment, when the transponder needs to be switched when the program number is changed, the P in the PAT is changed.
Since the MT_PID extraction and the transponder switching are performed in parallel in time (step n24), the time required for changing the program number accompanying the transponder switching can be further shortened as compared with the first embodiment. It is possible to further reduce the discomfort that is given to the.

(Embodiment 3) Next, a third embodiment of the present invention will be described.

The basic structure of this embodiment is similar to that of the first embodiment shown in FIG.

Also in this embodiment, as in the first embodiment, the transponder number is assigned to the upper 4 bits of the program number, and the relationship between the transponder number and the transport stream ID is set in the same manner as in the first embodiment. As shown in Table 1, the relationship between the transport stream ID and the program number is shown in Table 2.

In this embodiment, as in the second embodiment,
PAT of all transponders from sender (maximum 1 in this case)
6) in the MPEG2 private section.

Next, the processing when changing the program number in this embodiment will be described with reference to the flow chart of FIG.

In this embodiment, even when the program number x is being received (step n30), the receiving device is able to receive the program number x.
Transponder (Transponder Stream I
Among the transponders other than D = Tx), the PAT of the transponder whose number is adjacent to the transponder to which the program number x belongs is received in the private section. The private sections in which these PATs are described are stored in the area of the table storage unit 106. This area is determined by the control unit 108.

Here, the transport stream ID of the adjacent transponder is (Tx ± Tp) (T
p is a transponder that is some natural number less than the total number of transponders. If the number of all transponders is 16, Tp may be set to a value of 2 to 5, for example. This may be set in the receiving device in advance,
It may be possible for the viewer to set manually.

When the viewer changes the program number from x to y (≠ x) and sets the program number y (step n31),
The control unit 108 immediately identifies the transponder, that is, the transport stream ID, by looking at the upper 4 bits of the program number y (step n3).
2). Next, as a first determination, it is determined whether the transport stream ID = Ty of the program y is the same as the transport stream ID = Tx of the program number x (step n33). As a judgment of 2,
It is determined whether or not the transponder adjacency criterion | Ty−Tx | ≦ Tp is satisfied (step n34). If the transponder adjacency criterion is satisfied, the control unit 108 displays the PAT having the transport stream ID = Ty of the program number y in parallel in time with the switching of the reception of the transponder, as in the second embodiment. The PMT_PID corresponding to the program number y is read from the storage unit 106 and extracted (step n35). If Ty and Tx do not satisfy the transponder adjacency condition, the control unit 108 switches the transponder reception (step n3).
6) to PAT with transport stream ID = Ty
Is received and newly stored in the table storage unit 106, and the PMT_PID corresponding to the program number y is extracted (step n37). The process after the control unit 108 extracts the PMT_PID is the same as that in the first embodiment (step n3).
8, 39).

In this embodiment, when the transponder needs to be switched when changing the program number, if the transponder to be switched belongs to an adjacent transponder, the PMT_PID extraction in the PAT and the transponder switching are performed in time. Since they are performed in parallel, the time required for changing the program number due to the switching of the transponder can be further shortened as compared with the first embodiment.

Further, in this embodiment, unlike the second embodiment, the PATs of all the transponders are not received and stored in the memory, but the PATs of the adjacent transponders are received in the private section and stored in the memory. Since the data is stored, the capacity of the memory can be reduced as compared with the second embodiment.

(Embodiment 4) Next, a fourth embodiment of the present invention will be described.

The basic structure of the fourth embodiment is similar to that of the first embodiment shown in FIG.

In this embodiment, as in the first embodiment, the transponder number is assigned to the upper 4 bits of the program number, and the relationship between the transponder number and the transport stream ID is set in the same manner as in the first embodiment. As shown in Table 1, the relationship between the transport stream ID and the program number is shown in Table 2.

In this embodiment, as in the third embodiment,
PAT of all transponders from sender (maximum 1 in this case)
6) in the MPEG2 private section.

The processing for changing the program number in this embodiment will be described with reference to the flowchart of FIG.

In the above-mentioned third embodiment, a step (step n34) of determining whether or not the transponder having the program number before the change and the transponder having the program number after the change are adjacent to each other when the program number is changed is provided. but in this embodiment, this step is replaced by a step of determining (step n34 ₀₎ whether the transport stream ID the viewer set in advance the receiving device.

If the transport stream ID of the changed program number is set by the viewer in advance in the receiving device, the control unit 108 operates in parallel with the switching of the reception of the transponder and the transport stream of the program number y. I
The PAT sent in the private section having D = Ty is read from the table storage unit 106, and the PMT_PID corresponding to the program number y is extracted (step n).
35). If the transport stream ID of the changed program number is not set by the viewer in advance by the receiving device, the control unit 108 switches the reception of the transponder (step n36) and then the PAT of the transport stream ID = Ty. Is received and is newly stored in the table storage unit 106, and PMT_PID corresponding to the program number y is received.
Is extracted (step n37). The subsequent processing is exactly the same as in the third embodiment.

According to this embodiment, in the processing steps of the above-mentioned third embodiment, the step of determining whether or not the transponders before and after the change are adjacent to each other when the program number is changed is viewed when the program is changed. By replacing it with the step of determining whether the user belongs to the preset transport stream ID, the time required for the program change accompanied by the viewer switching to the transponder having the preset transport stream ID is shortened. As a result, it is possible to reduce the time difference from the time required to change the program without switching the transponder, and to reduce the discomfort felt by the viewer.

(Fifth Embodiment) Next, a fifth embodiment of the present invention will be described.

The basic structure of the fifth embodiment is similar to that of the first embodiment shown in FIG.

In this embodiment, as in the first embodiment, the transponder number is assigned to the upper 4 bits of the program number, and the relationship between the transponder number and the transport stream ID is set in the same manner as in the first embodiment. As shown in Table 1, the relationship between the transport stream ID and the program number is shown in Table 2.

In this embodiment, as in the third embodiment,
PAT of all transponders from sender (maximum 1 in this case)
6) in the MPEG2 private section.

The process for changing the program number in this embodiment will be described with reference to the flowchart of FIG.

In the third embodiment described above, the step (step n34) of determining whether or not the transponder having the program number before the change and the transponder having the program number after the change are adjacent to each other when the program number is changed is provided. , In this embodiment, the transport stream IDs of K (K is a natural number) different transponders that have recently received this step.
Step (step n)
34 ₁ ). That is, of the PATs sent in the private section, the control unit 108 determines that the transport stream ID of the PAT matches the transport stream ID of the K different recently received transponders, and the PAT is stored in the table storage unit 106. Store it. The value of K may be set to, for example, 2 to 6, but may of course be set to a larger value. If the transport stream ID of the changed program number belongs to the K recently received transponders, the control unit 1
In parallel with the switching of the reception of the transponder 08, the PAT sent as the private section having the transport stream ID = Ty of the program number y is read from the table storage unit 106 and the PMT_PID corresponding to the program number y is extracted. (Step n35). If the transport stream ID of the changed program number does not belong to the K most recently received transponders, the control unit 108 switches the reception of the transponders (step n36) and then the transport stream IDs.
= Py of Ty is received and the table storage unit 106 is newly added.
And the PMT_PID corresponding to the program number y is extracted (step n37). The subsequent processing is exactly the same as in the third embodiment.

According to this embodiment, in the processing steps of the third embodiment, the step of determining whether or not the transponders are adjacent to each other when the program number is changed includes the steps of the K different transponders that have been recently received when the program number is changed. By replacing with the step of determining whether or not the transport stream ID belongs, the time required for program change involving switching to K recently received transponders can be shortened, and the time required for program change without switching transponders can be shortened. By reducing the time difference between and, it is possible to reduce the discomfort felt by the viewer.

(Sixth Embodiment) Next, a sixth embodiment of the present invention will be described.

The basic structure of the sixth embodiment is similar to that of the first embodiment shown in FIG.

In this embodiment, as in the first embodiment, the transponder number is assigned to the upper 4 bits of the program number, and the relationship between the transponder number and the transport stream ID is set in the same manner as in the first embodiment. As shown in Table 1, the relationship between the transport stream ID and the program number is shown in Table 2.

In this embodiment, as in the third embodiment,
PAT of all transponders from sender (maximum 1 in this case)
6) in the MPEG2 private section.

The processing when changing the program number in this embodiment will be described with reference to the flowchart of FIG.

In the third embodiment described above, the step (step n34) of determining whether or not the transponder having the program number before the change and the transponder having the program number after the change are adjacent to each other when the program number is changed is provided. In this embodiment, this step is replaced with a step (step n34 ₂ ) of determining whether or not the transport stream ID of the transponder frequently used by the viewer is included.

The viewer selects the most significant M (M is a natural number less than or equal to L) among the transport stream IDs of the L transponders set when the program number is changed L times (L is a natural number) in the past. It is assumed that this is a transport stream ID of a transponder that is frequently used. The values of L and M may be set to L = 40 and M = 5, for example, but the set value of M is arbitrary as long as it does not exceed the number of transponders.

P sent in the private section
Among ATs, the control unit 108 determines that the transport stream ID matches the transport stream ID of the transponder frequently used by the viewer, and stores it in the table storage unit 106. If the transport stream ID of the changed program number belongs to the transponder that the viewer frequently uses, the control unit 10
In parallel with switching the reception of the transponder, 8 reads out the PAT having the transport stream ID = Ty of the program number y from the table storage unit 106 and extracts the PMT_PID corresponding to the program number y (step n).
35). If the transport stream ID of the changed program number does not belong to the transponder frequently used by the viewer, the control unit 108 switches the reception of the transponder (step n36) and then the PAT of the transport stream ID = Ty. Is received and is newly stored in the table storage unit 106, and PMT_corresponding to the program number y
The PID is extracted (step n37). The subsequent processing is exactly the same as in the third embodiment.

According to this embodiment, in the processing step of the third embodiment, the step of determining whether or not the transponders are adjacent to each other when the program number is changed is the transport stream ID of the transponder frequently used by the viewer. The time required to change the program that involves switching to a transponder frequently used by the viewer is shortened by replacing it with the step of determining whether the program number changes without changing the transponder. It is possible to reduce the time difference between, and it is possible to reduce the feeling of strangeness given to the viewer.

In each of the first to sixth embodiments, the transponder number in the program number is assigned to the upper 4 bits, but J bits (J is a natural number less than the bit width of the program number) in a part of the program number. ) Is good.

In the first to sixth embodiments, the same thing can be said when the transponder number in satellite broadcasting is used as a physical channel for digital terrestrial broadcasting or digital CATV broadcasting.

[0090]

As described above, according to the present invention, the transponder number is assigned to a part of the program number, and when the program number is changed, the transponder number is identified from the changed set program number. When changing the program number that involves switching the reception of transponders, it is no longer necessary to search the number of the transponder to which the changed program number belongs, shortening the time required to change the program, and changing the program without switching the transponder, It is possible to reduce the time difference between the program change accompanied by the transponder switching and the discomfort felt by the viewer.

Further, by transmitting the PATs of all transponders in the private section, the time required for program change involving switching of transponders can be further shortened, and the sense of discomfort given to the viewer can be further reduced.

[Brief description of drawings]

FIG. 1 is a block diagram of a receiving apparatus of the present invention.

FIG. 2 is a diagram showing allocation of transponder numbers to program numbers.

FIG. 3 is a flowchart for explaining the operation of the first embodiment of the present invention.

FIG. 4 is a flowchart for explaining the operation of the second embodiment of the present invention.

FIG. 5 is a flowchart for explaining the operation of the third embodiment of the present invention.

FIG. 6 is a flowchart for explaining the operation of the fourth embodiment of the present invention.

FIG. 7 is a flowchart for explaining the operation of the fifth embodiment of the present invention.

FIG. 8 is a flowchart for explaining the operation of the sixth embodiment of the present invention.

FIG. 9 is a flowchart for explaining the operation of the conventional example.

[Explanation of symbols]

 101 reception unit 102 reception transponder switching unit 103 demodulation unit 104 channel decoding unit 105 transport stream separation unit 106 table storage unit 107 data stream storage unit 108 control unit 109 clock recovery unit

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display location H04N 7/24 7/20 (72) Inventor Tadashi Kubota 1006 Kadoma, Kadoma-shi, Osaka Matsushita Electric Industrial Within the corporation

Claims (10)

[Claims] 1. The transmitting side uses a part of the program number as a transponder number for transmitting the program having the program number, and when the receiving side changes the program number, the changed program number is changed from the changed program number. The number of the transponder transmitting the program is identified, it is determined whether the number of the identified transponder is the same as the number of the transponder being received, and when it is determined that they are not the same, the number of the identified transponder is determined. A program switching method in digital satellite broadcasting, characterized in that reception is switched to a transponder having a number. 2. The transmitting side uses a part of the program number as a transponder number for transmitting the program of the program number, and when the receiving side changes the program number, the changed program number is changed from the changed program number. The step of identifying the number of the transponder transmitting the program, the step of determining whether the number of the identified transponder is the same as the number of the transponder being received, and when it is determined that they are not the same, A step of switching to reception of the identified transponder number by the transponder; a step of extracting a program map table packet identifier corresponding to the program number in the program linkage table including the changed set program number; Program map table A program map table having a packet identifier, and an elementary package corresponding to the program number that has been changed and set. Extracting the print identifier,
Extracting the packet having the extracted elementary packet identifier from the transport stream, the program switching method in digital satellite broadcasting. 3. On the transmitting side, a part of the program number is used as the number of the transponder that transmits the program of the program number, and the program linkage table of all the transponders is sent as private data to the transport stream of each transponder. At the receiving side, when changing the program number, the step of identifying the transponder number that transmits the program from the changed set program number, and the identified transponder number is the same as the receiving transponder number. And a step of extracting a program map table packet identifier corresponding to the program number from the program linkage table including the changed program number when it is determined to be the same. And when it is determined that they are not the same, the transponder with the number of the identified transponder is received. In parallel with the switching of the program, a step of extracting a program map table packet identifier corresponding to the changed program number from the program association table sent as the private data, and the extracted program map table packet identifier In the program map table having the step of extracting the elementary packet identifier corresponding to the changed program number, and the step of extracting the packet having the extracted elementary packet identifier from the transport stream. A program switching method in digital satellite broadcasting characterized by the above. 4. On the transmitting side, a part of the program number is used as the number of the transponder that transmits the program of the program number, and the program linkage table of all the transponders is sent as private data to the transport stream of each transponder. At the receiving side, when changing the program number, the step of identifying the transponder number that transmits the program from the changed set program number, and the identified transponder number is the same as the receiving transponder number. And the second determination step of determining whether the transponder of the identified transponder number satisfies a predetermined condition when it is determined that they are not the same. And the step of determining the number of the identified transponder when it is determined that the predetermined condition is not satisfied. A step of switching reception to the responder, a step of extracting a program map table packet identifier corresponding to the program number in the program linkage table including the changed program number, and it is determined that the predetermined condition is satisfied. At the same time as switching the reception to the transponder of the identified transponder number, in parallel with the program map table packet corresponding to the changed program number from the program association table transmitted as the private data. In the step of extracting the identifier and the program map table having the extracted program map table packet identifier,
A digital satellite broadcast comprising: a step of extracting an elementary packet identifier corresponding to the changed program number; and a step of extracting a packet having the extracted elementary packet identifier from a transport stream. Program switching method in. 5. The digital signal according to claim 4, wherein the predetermined condition is whether or not an absolute value of a difference between the number of the identified transponder and the number of the transponder being received is equal to or less than a predetermined value. Program switching method in satellite broadcasting. 6. The program switching method in digital satellite broadcasting according to claim 4, wherein the predetermined condition is whether or not the number of the identified transponder is included in a preset number of transponders. 7. The program switching in digital satellite broadcasting according to claim 4, wherein the predetermined condition is whether or not the number of the identified transponder is included in the numbers of the plurality of transponders received so far. Method. 8. The program switching method in digital satellite broadcasting according to claim 4, wherein the predetermined condition is whether or not the number of the identified transponder is a number of a transponder frequently used by a viewer. 9. The number of transponders that are frequently used is the upper M (M is L) that has been set a large number of times among the transponder numbers that were set when the program number was changed L times (L is a natural number) in the past. 9. The program switching method in digital satellite broadcasting according to claim 8, wherein the transponder number is the following natural number. 10. An apparatus for receiving a digital satellite broadcast that transmits a part of a program number as a transponder number for transmitting the program of the program number, and the transponder that transmits the program from a program number that is changed and set. The identification means for identifying the number of the transponder, the determination means for determining whether or not the number of the identified transponder is the same as the number of the transponder being received, and the identification means for determining whether the number is not the same. A switching means for switching the reception to the transponder of the selected transponder number, and a digital satellite broadcast receiving apparatus, comprising: