JP4966738B2 - Selective transmission device - Google Patents

Description

  The present invention relates to a selective transmission device that receives broadcast signals and selectively transmits some of them to a reception device.

  At present, analog and digital broadcasting services (referred to as terrestrial broadcasting or satellite broadcasting, hereinafter referred to simply as “broadcasting services”, which do not distinguish between analog and digital) using radio waves (hereinafter referred to as “broadcast signals”) by each broadcasting station are radio frequencies. Of these, a certain frequency band is used. In the case of terrestrial broadcasting, 6 MHz in the VHF to UHF band is used, and in the case of satellite broadcasting (BS, CS broadcasting), 27 MHz in the 12 GHz band is used. Hereinafter, the frequency band of the radio frequency used by each broadcast station for the broadcast signal is referred to as a channel.

  In the case of a digital broadcast service, a digital broadcast signal transmitted through a certain channel of each broadcast station is called a TS (transport stream), and this TS has a unique identifier (TS id) for each TS.

  In a receiving apparatus that receives this digital broadcast signal (hereinafter referred to as a digital broadcast receiving apparatus), a list of TS id of the TS, service id of the program transmitted by the TS, and a channel to be transmitted is stored in a memory. Thus, by referring, a desired TS can be selected from the TSs to be transmitted, and the channel can be viewed together. Hereinafter, the list of TS id, service id and the corresponding channel is referred to as a receivable frequency table.

  Usually, in broadcast services, the number of broadcast signals and channels that can be received differs depending on the region, and the number of broadcast signals and channels that can be received from a certain period may increase or decrease, or the channel of a certain broadcast signal may be changed. .

  For this reason, the digital broadcast receiving apparatus has a function of searching for a receivable channel and performing a process of storing a receivable frequency table in the memory of the receiving apparatus in order to cope with such differences and changes in the broadcasting service. ing. Hereinafter, this process is referred to as a scan process.

The scan processing of this digital broadcast receiving apparatus includes an initial scan and a rescan as shown in ARIB TR-B14 6.2.
The initial scan indicates that the receivable frequency table previously held in the memory of the receiving device is cleared and the scan is performed, and the rescan performs the scanning process without clearing the memory of the receiving device. It points to that. Note that a channel newly discovered by rescanning is added to the receivable frequency table of the receiving apparatus.

  In addition to the case where the viewer receiving the broadcast service performs the scanning process by operating the receiving device, the broadcast service provider who provides the broadcast service as in the cable TV service. However, it may be performed remotely with respect to a receiving device installed at the viewer's house.

  In this case, for example, as shown in Chapter 7 of JCL SPEC-007 (terrestrial digital television broadcast transmodulation operation specification), when there is an increase / decrease or change in channel, a request for a reserved scan is made in advance to the receiving apparatus. And the receiver automatically performs the scanning process, so that the viewer can use the changed service without manually performing the scanning process.

  As an example of such scan processing, a plurality of frequency tables that can be received in the region are stored in a memory, and a list of the plurality of frequency tables is displayed and the frequency table can be selected, so that other frequencies can be selected. Example of switching to a table and receiving broadcasts that can be received over other regions (see Patent Document 1), or storing a region identifier together with a plurality of frequency tables in a memory, and selecting by region identifier An example in which a desired broadcast can be received while performing a channel search at a high speed and a service specific to a region can be received (see Patent Document 2) has been reported.

JP 2004-15499 A JP 2004-228769 A

  However, the scan processing described as the background art above assumes a system in which all broadcast signals transmitted from the transmission device are transmitted to the reception device. The receiving apparatus can add all TSs and channels to the receivable frequency table once the initial scanning or the rescanning is performed. Therefore, the scanning process of the receiving device used in such a system targets a broadcast signal transmitted to the receiving device during the process, and the receiving device does not send a request for each broadcast signal to the transmitting device. Further, the program viewing request command is merely exchanged between the remote controller of the receiving device and the main body, and is not assumed to be transmitted / received via the network.

On the other hand, as a broadcasting system, there is a broadcasting system in which all broadcast signals (hereinafter, all broadcast signals) transmitted from a transmission device provided in each broadcasting station are not simultaneously transmitted to a digital broadcast reception device.
The broadcast system includes a selective transmission device that receives a request (program viewing request) from a digital broadcast receiving device for a certain broadcast signal and transmits only the requested broadcast signal to the digital broadcast receiving device. ing.

  For example, as an example of such a broadcasting system, there is IP multicast distribution of a digital broadcasting service that is being considered for practical use. In IP multicast distribution, an ISP (Internet Service Provider) edge router or the like plays the role of a selective transmission device.

  In the selective transmission device of such a broadcast system, the requested broadcast signal is selected from the broadcast signals transmitted to the selective transmission device in response to a program viewing request from the digital broadcast reception device, and the digital broadcast reception device is selected. Transmit but do not transmit unrequested broadcast signals. As a result, compared to the case where all broadcast signals are transmitted, the transmission path band between the selective transmission apparatus and the digital broadcast receiving apparatus can be vacant, so the unused band is used for another communication, etc. Efficiency can be improved.

  The broadcast signal request may be made when the digital broadcast receiver transmits a request command over the network. However, when a general digital broadcast receiver that directly receives radio waves is used, the broadcast signal request is received. Since a request for a broadcast signal is made from the remote controller of the apparatus to the main body, the selective transmission apparatus can detect the request by receiving the signal of the remote controller.

  In addition to the case where the selective transmission device and the digital broadcast receiving device are connected one-to-one, there may be a case where two or more digital broadcast reception devices are connected to one selective transmission device. In this case, it is desirable that the selective transmission device can select and output the same number of broadcast signals as the number of reception signals, assuming that each digital broadcast reception device views different broadcast signals. In this case, the selective transmission device multiplexes a plurality of broadcast signals by frequency multiplexing or time division multiplexing and transmits the multiplexed signals to the transmission path.

  When the scanning process of the digital broadcast receiving device is applied to a broadcast system in which such a selective transmission device is interposed, the viewer manually switches the broadcast signal output of the selective transmission device, and the digital broadcast receiving device There is a problem in that it is necessary to perform the scanning process by manual operation until all broadcast signals are completed, which is very troublesome.

  In addition, when a plurality of digital broadcast receivers are connected to the selective transmission device, a broadcast output from the selective transmission device when a receiver other than the digital broadcast receiver that wants to perform a scan process performs a program request or a scan process. The number of signals may have already reached the maximum number that can be output by the selective transmission device. In this case, the scanning process cannot be performed without waiting for the number of broadcast signals output from the selective transmission device to be vacant, for example, when another receiving device switches programs. The waiting time at this time is random because it depends on an operation such as program switching performed by another receiving apparatus at an arbitrary timing. It is virtually impossible for a viewer who manually performs the scanning process to wait for this time before proceeding.

  Further, when a reservation scan request is made to the digital broadcast receiving device as in the above-described cable television, for example, the selective transmission device relays the reservation scan request command of the transmission device provided in the broadcasting station, and the command Thus, a method of performing a scanning process by switching a broadcast signal and a channel to be transmitted to the digital broadcast receiving apparatus can be considered.

In this case, manual operation by the viewer is not necessary, but reservation of the scan process is made without distinguishing between the newly installed digital broadcast receiver and the digital broadcast receiver that has already been installed and has completed the scan process. Therefore, an extra load is applied to the digital broadcast receiving apparatus that has already finished the scanning process.
In addition, since it is considered that the timing of installation of the digital broadcast receiver by the viewer is arbitrary, the reservation scan request command must always be transmitted repeatedly, and the channel bandwidth in the transmission path is used inefficiently. Will be.

  The present invention is performed in such a background, and in a broadcasting system including a selective transmission device in which all broadcast signals are not transmitted to the reception device at the same time, direct reception that does not assume the selective transmission device is present. It is an object of the present invention to provide a selective transmission device that can easily perform scan processing of a general reception device for use without causing inefficiency in use of a transmission band.

In order to solve the above-described problem, the selective transmission device according to claim 1 is configured to transmit the selected broadcast signal to a reception device that outputs a broadcast signal selected from a plurality of received broadcast signals as a broadcast program. A transmission apparatus, comprising a control signal transmission / reception unit, a signal selection unit, a broadcast signal determination unit, a broadcast signal selection unit, a scan unprocessed broadcast signal determination unit, and a rescan control signal transmission unit did.

According to such a configuration, the selective transmission device stores the broadcast signal list in which the plurality of broadcast signals are associated with the channels specified by the frequency at which each broadcast signal is received by the control signal transmission / reception unit in the reception device. received to Rutotomoni from the receiver scan processing control signal for executing a scanning process to be held in, it receives a viewing request control signal for viewing request for broadcast program reception apparatus. Then, the selective transmission device outputs, to the reception device, a broadcast signal that has not been subjected to the scan processing among the plurality of received broadcast signals based on the scan processing control signal received by the control signal transmission / reception unit by the signal selection unit. At the same time, a broadcast signal based on the viewing request control signal is selected from the plurality of received broadcast signals and output to the receiving device.
Here, the selective transmission device determines the broadcast signal to be output by the broadcast signal determination means. Then, the selective transmission device selects and outputs the broadcast signal by the broadcast signal selection unit based on the determination of the broadcast signal determination unit.
In addition, the selective transmission device stores the scan processed and unscanned broadcast signals of the receiving device that has transmitted the scan processing control signal by the scan unprocessed broadcast signal determination means, and outputs it from the unscanned broadcast signals. The broadcast signal to be determined is determined. Then, the selective transmission device requires the scanning process for the unscanned broadcast signal so that the receiving device that has transmitted the scan processing control signal performs the scanning process by the rescan control signal transmission unit. The rescan control signal for updating the list of broadcast signals obtained by the reception device by the scan process is transmitted to the control signal transmission / reception unit after being delayed by the time.

The selective transmission device according to claim 2 is the selective transmission device according to claim 1, wherein the signal selection unit holds in advance when the scan processing control signal received by the control signal transmission / reception unit is input. the corresponding scan processing control signal from the scan processing control signals corresponding to each of the receiving apparatus is to output the previous SL rescan control signal, said control signal transmitting and receiving unit, the re-scan control signal, the receiving It outputs to an apparatus.

  According to such a configuration, when the scan processing control signal received by the control signal transmission / reception unit is input by the signal selection unit, the selective transmission device has a scan processing control signal corresponding to each of the reception devices held in advance. The corresponding scan processing control signal is output as a rescan control signal for updating the broadcast signal list obtained by the scan processing, and the control signal transmitting / receiving unit outputs the rescan control signal to the receiving device.

The selected transmission device according to claim 3, in selecting transmission device according to claim 1 or claim 2, wherein the signal selector is provided with a broadcast signal list acquisition unit, said broadcast signal determining means, viewing request broadcast Signal determining means is provided.

According to such a configuration, the selective transmission device acquires the broadcast signal list by collecting the channel specified by the identifier and the frequency attached to each of the plurality of received broadcast signals by the broadcast signal list acquisition unit. Subsequently, the selective transmission apparatus determines a broadcast signal to be output from the broadcast signal list based on the viewing request control signal received from the control signal transmission / reception unit by the viewing request broadcast signal determination unit. Then, the selective transmission device selects and outputs the broadcast signal by the broadcast signal selection unit based on the determination of the broadcast signal determination unit.

The selective transmission apparatus according to claim 4 is the selective transmission apparatus according to any one of claims 1 to 3, wherein the signal selection unit includes a broadcast signal grasping unit for viewing. .

According to such a configuration, when the plurality of reception devices are connected to the selected transmission device by the viewing broadcast signal grasping unit, the selection transmission device broadcasts the reception device that is not currently performing the scan process. Know the signal and get the total number. Then, the selective transmission device uses the broadcast signal determination means for the scanning process with the maximum number obtained by subtracting the total number obtained by the viewing broadcast signal grasping means from the maximum number of broadcast signals that can be output simultaneously by the selected broadcast apparatus. The broadcast signal to be output to is determined.

The selective transmission device according to claim 5 is the selective transmission device according to claim 3, wherein the viewing request broadcast signal determination unit does not perform the scan processing and does not transmit the scan processing control signal. A broadcast signal to be output is determined according to the viewing request control signal from the apparatus.

  According to such a configuration, the selective transmission device stores the scan processed and unscanned broadcast signals of the reception device that has transmitted the scan processing control signal by the scan unprocessed broadcast signal determining means, and stores the scan unprocessed broadcast signal. Broadcast signal to be output is determined. Subsequently, the selective transmission device determines a broadcast signal to be output according to the viewing request control signal from the receiving device that is not performing the scanning process and not transmitting the scanning process control signal, by the viewing request broadcast signal determination unit. . Then, the selective transmission device requires the scanning process for the unscanned broadcast signal so that the receiving device that has transmitted the scan processing control signal performs the scanning process by the rescan control signal transmission unit. The rescan control signal is transmitted to the control signal transmission / reception unit with a delay of time.

  A selective transmission device according to a sixth aspect is the selective transmission device according to the third aspect, wherein the broadcast signal determining means includes a priority order broadcast signal determining means.

  According to such a configuration, the selective transmission device determines the broadcast signal output from the signal selection unit according to a predetermined priority when the plurality of reception devices are provided by the priority order broadcast signal determination means.

  The selective transmission device according to claim 7, in the selective transmission device according to claim 3, wherein the broadcast signal determination unit repeatedly transmits the rescan control signal until there is no unprocessed broadcast signal. Features.

  According to such a configuration, the selective transmission device repeatedly transmits the rescan control signal by the broadcast signal determination unit until there is no unprocessed broadcast signal.

According to the first aspect of the present invention, it is possible to transmit / receive a control signal (scan processing control signal, viewing request control signal: command) to / from the receiving device, and cause the receiving device to perform scanning processing, It is possible to allow an operator (viewer) to selectively view a broadcast program. Then, in a broadcasting system including a selective transmission device that does not transmit all broadcast signals to the reception device at the same time, a scan process of a general reception device for direct reception that does not assume the selective transmission device is easily performed. be able to.
In addition, the broadcast signal to be transmitted for rescanning can be determined and transmitted, and in the case of rescanning, the rescan control signal can be sent at an appropriate timing, leading to inefficient use of the transmission band. Can be done without.

  According to the second aspect of the present invention, transmission of the rescan control signal to the receiving device and reception of the scan processing control signal and the viewing request control signal from the receiving device are performed, and the scanning processing is performed on the receiving device. It is possible to allow the operator (viewer) to perform selective viewing of the broadcast program.

  According to the third aspect of the present invention, a broadcast signal list is created from the received broadcast signals, and a broadcast signal to be output from the broadcast signal list is selected, so that the broadcast signal corresponding to the request from the receiving device can be selected. Output can be done.

According to the invention of claim 4, grasp the broadcast signal currently being viewed, with the maximum number of broadcast signals available for the scanning process, Rukoto to determine the broadcast signal to scan process Can do.

  According to the fifth aspect of the present invention, a broadcast signal to be transmitted in response to a viewing request from the receiving apparatus and a broadcast signal to be transmitted for rescanning are determined and transmitted. Since the rescan control signal can be sent at a proper timing, the transmission band can be used without inefficiency.

  According to the invention described in claim 6, it is possible to select an optimum broadcast signal by giving priority.

  According to the seventh aspect of the present invention, once re-scanning is started, the scanning process can be continued until there is no unprocessed broadcast signal.

Hereinafter, the present invention will be described in detail with reference to the drawings.
FIG. 1 is a block diagram of an embodiment of a broadcasting system to which a selective transmission device of the present invention is applied. The broadcast signal transmitted here is a TS (transport stream) of an MPEG-2 system of digital terrestrial broadcasting that has been subjected to OFDM (Orthogonal Wave Frequency Division Multiplexing) modulation according to the ISDB-T format.

The broadcasting system includes a transmission device 2 provided in a broadcasting station, a selective transmission device 1 that receives all TS (all broadcast signals) broadcast from the transmission device 2, and a transmission from the selective transmission device 1. It comprises a plurality of receiving devices 3 that receive broadcast signals.
The transmission apparatus 2 performs OFDM modulation on the MPEG-2 TS in the ISDB-T format and transmits it by frequency multiplexing.

  The selective transmission device 1 selects a modulated wave that transmits a TS requested by the reception device 3 from the plurality of OFDM modulation waves transmitted from the transmission device 2 and transmits the selected modulation wave to the reception device 3 (hereinafter, referred to as “the transmission device”). The process in which the selective transmission apparatus 1 “outputs TS as a modulated wave” is simply referred to as “output TS”). Details will be described later.

  The receiving device 3 is a general device (similar to the conventional device) that directly receives OFDM modulated waves, and is selected and transmitted by a program request command from a remote controller operated by a viewer (a receiving device remote controller 32 described later). A TS request to 1 and, as a result, a TS (selected broadcast transmission) transmitted from the selective transmission apparatus 1 is received, and video / audio decoding is performed on the MPEG-2 TS extracted by demodulation. It is.

(Regarding the control signal transmission / reception system between the selective transmission device and the reception device)
FIG. 2 shows transmission / reception of a scan processing control signal (command) for scan processing of the receiving device 3 and a viewing request control signal (command) for viewing a program exchanged between the selective transmitting device 1 and the receiving device 3. It is explanatory drawing which shows a system | strain.

  The selective transmission device 1 includes a signal selection unit 11 that selects and outputs a TS among all TSs, and a control signal transmission / reception unit 12 that exchanges a scan processing control signal and a viewing request control signal with the reception device 3. I have.

  The receiving device 3 includes a receiving device main body 31 that decodes video and audio after receiving and demodulating a TS, and a receiving device remote control 32 that performs switching of broadcast programs to be output and various controls of the receiving device main body 31. Has been. The receiving device body 3 is provided with storage means 311 configured by a general memory or the like.

Then, the selected broadcast signal is output from the signal selection unit 11 of the selective transmission device 1 to the reception device body 31 of the reception device 3 via a signal transmission path (such as a coaxial cable).
In addition, between the signal selection unit 11 and the control signal transmission / reception unit 12 of the selective transmission device 1, “rescan” control is performed from the signal selection unit 11 to the control signal transmission / reception unit 12 via a control signal transmission path (such as a LAN). A signal (rescan control signal) is transmitted, and an “initial / rescan” and “broadcast signal request” control signals (scan processing control signal and viewing request control signal) are transmitted from the control signal transmission / reception unit 12 to the signal selection unit 11. ing.

Further, the “initial / rescan” and “broadcast signal request” control signals (scan control signal and viewing request control signal) are omitted from the receiver remote controller 32 of the receiver 3 to the control signal transmission / reception unit 12 of the selective transmitter 1. Is output, and the same control signal is transmitted to the receiver main body 31.
A rescan control signal (not shown) is output from the control signal transmission / reception unit 12 of the selective transmission device 1 to the reception device body 31 of the reception device 3.

  In this embodiment, the signal selection unit 11 and the control signal transmission / reception unit 12 are housed in the frame (housing) of the selective transmission device 1, but the signal selection unit 11 and the control signal transmission / reception unit 12 are separately provided. For example, a command may be exchanged using a transmission line such as a LAN, a telephone line, or a coaxial cable.

The signal selection unit 11 of the selective transmission device 1 transmits a rescan control signal to the reception device 3 via the control signal transmission / reception unit 12, and the reception device 3 selects and outputs an unprocessed TS. By performing the above processing repeatedly until the receiving device 3 has no unprocessed TS, the receiving device 3 can acquire the receivable frequency table.
The details of this procedure will be described in the first and second embodiments described below.

  In FIG. 2, only one receiving device 3 is connected to the selective transmission device 1, but there may be a plurality of receiving devices 3. When there are a plurality of receiving apparatuses 3 to be connected, assuming that each requests and views a different TS, the number of TSs that can be selected and output by one selected transmitting apparatus 1 is I.

(Configuration of Selective Transmission Device [First Embodiment])
FIG. 3 shows a functional block diagram of the first embodiment of the selective transmission apparatus 1 of the present invention. FIG. 3 shows a case where there is one receiver 3 from which the broadcast signal is output from the selective transmitter 1 (when the number of output channels is 1). Note that the number of TSs transmitted to the selective transmission device 1 is M. Here, M ≧ 2. In the case of M = 1, it is not necessary for the selective transmission apparatus 1 to select a TS, and such a system is not a subject of the present invention (originally, the selective transmission apparatus 1 is unnecessary). The reason why the number of outputs of the selective transmission apparatus 1 is one is that the viewer usually watches one TS (one broadcast program). Incidentally, it is conceivable that the number of outputs is two or more (it is also assumed that a viewer watches two or more broadcast programs at the same time with one receiving device 3), but it is not touched here.

  As shown in FIG. 3, the selective transmission apparatus 1 includes a signal selection unit 11 having a broadcast signal list acquisition unit 111, a broadcast signal determination unit 112, and a broadcast signal selection unit 113, a scan processing control signal transmission / reception unit 121, and a viewing / listening unit. And a control signal transmission / reception unit 12 having a control signal transmission / reception unit 122 and a signal relay unit 123.

  The broadcast signal list obtaining unit 111 obtains M TS lists (broadcast signal lists) to be transmitted by collecting channels identified by identifiers (TS id) and frequencies attached to the respective broadcast signals. Is. As another TS list acquisition method, in addition to demodulating and acquiring all the modulated waves transmitted to the selective transmission apparatus 1, a method of preparing in advance information on a channel for transmitting each TS is considered. It is done.

  The broadcast signal determining unit 112 receives a request for initial scan or rescan from the receiver remote controller 32 of the receiver 3 and triggers the receiver main body 31 of the receiver 3 to end the initial scan or rescan as a trigger. In addition to determining one of the TSs, a rescan control signal is output to the receiving apparatus main body 31 via the control signal transmission / reception unit 12 in order to perform scanning processing on the determined TS. .

  The broadcast signal selection unit 113 selects the TS determined by the broadcast signal determination unit 112 from the M TSs and outputs the TS to the reception device main body 31 of the reception device 3 from the transmission path.

  The scan processing control signal transmission / reception means 121 receives a scan processing control signal (request for “initial scan” or “rescan”) output from the reception device remote controller 32 of the reception device 3 and transmits it to the signal selection unit 11. It is.

  The viewing control signal transmission / reception means 122 receives the viewing request control signal (“broadcast signal request”) output from the receiving device remote control 32 of the receiving device 3 and transmits it to the signal selection unit 11.

  The signal relay unit 123 receives the rescan control signal (“rescan” control signal) output from the signal selection unit 11, and sends the rescan control signal to the receiving device 3 via the control signal transmission / reception unit 12. Output.

  According to the selective transmission device 1, by outputting a rescan control signal to the receiving device 3, the receiving device 3 can perform scanning processing, and a broadcast signal based on the viewing request control signal is output. Thus, the operator (viewer) can selectively watch the broadcast program. Then, in a broadcasting system including a selective transmission device 1 in which all broadcast signals are not transmitted to the reception device 3 at the same time, a general reception device scan process for direct reception that does not assume that the selective transmission device 1 is present is performed. It can be done easily.

(Configuration of Selective Transmission Device [Second Embodiment])
Next, FIG. 4 shows a functional block diagram of the second embodiment of the selective transmission apparatus 1 of the present invention.
FIG. 4 shows a case where there are N (N ≧ 2) receiving apparatuses 3 that output broadcast signals from the selective transmitting apparatus 1. Realizing the selective transmission apparatus 1 when the number of receiving apparatuses 3 to which broadcast signals are output is N by adding functional blocks to the functional block when there is only one receiving apparatus 3 shown in FIG. Can do.
Assume that the number of TSs transmitted to the selective transmission device 1 is M (M ≧ 2), and the selective transmission device 1 can output I (I ≧ 2) TS simultaneously.

When a plurality of receiving apparatuses 3 are connected, it is conceivable that the receiving apparatus 3 that performs scanning processing and the receiving apparatus 3 that is viewing a program transmitted by a certain TS are mixed. Therefore, it is assumed that the maximum number of TSs that can be simultaneously output by the selective transmission device 1 is at least 2 and I ≧ 2.
Incidentally, when I = 1, N receiving apparatuses 3 always view the same program. Further, even if I ≧ 2, when I <N, there is a restriction that N receiving apparatuses 3 cannot view different programs, and therefore it is desirable that I ≧ N.

Since the maximum number of TSs that need to be output simultaneously by the selective transmission device 1 is M, the maximum number of TSs that can be simultaneously output by the selective transmission device 1 is M or less (I ≦ M).
Here, an example of the number of output TSs that can be used for the scanning process is given. It is assumed that some of the N receiving apparatuses 3 are viewing a total of m TSs. At this time, if some of the remaining receiving apparatuses 3 perform the scanning process, the number of output TSs that can be used for the scanning process is (I−m). As the value of (I−m) is larger, the number of TSs that can be acquired by the receiving apparatus 3 in one scan process can be increased, and the number of repetitions of the scan process can be reduced.

  The selective transmission apparatus 1 includes a signal selection unit 11 having a broadcast signal list acquisition unit 111, a broadcast signal determination unit 112, a broadcast signal selection unit 113, and a viewing broadcast signal grasping unit 114, a scan processing control signal transmission / reception unit 121, and a viewing / listening unit. And a plurality of control signal transmission / reception units 12 having control signal transmission / reception means 122 and signal relay means 123. Note that the description of the same configuration (the same operation) as that shown in FIG. 3 is omitted.

  The broadcast signal determination unit 112 receives a request for initial scan or rescan from the receiver remote controller 32 of the receiver 3, and the receiver main body 31 of the receiver 3 triggers the end of the initial scan or rescan as a trigger for scan unprocessed TS to be output (maximum I-m) among the TSs of the received TS, and the receiver 3 is rescanned via the control signal transmission / reception unit 12 in order to cause the determined TS to be scanned. A signal is output.

  Then, the broadcast signal determination unit 112 receives the initial scanning or rescanning request from the receiving device 3 and each receiving device 3 starts the first scanning process and ends the several scanning processes. The information of the TS for which the scanning process has been completed is stored.

  Also, the broadcast signal selection means 113 is viewed by the TS (maximum I−m) for the scan processing determined by the broadcast signal determination means 112 and some receiving apparatuses 3 that are not performing the scan processing. The TS (m in total) that made the request (the one that transmitted the viewing request control signal) is selected from the M TSs and sent to the transmission path. This m is the number of TSs being viewed, and is grasped by transmitting the viewing request control signal from the receiving device 3 to the signal selecting unit 11 via the viewing control signal transmitting / receiving unit 122 of the control signal transmitting / receiving unit 12. Will be.

  The viewing broadcast signal grasping means 114 grasps the number (m) of TSs currently being viewed by the N receiving devices (at this time, the selective transmission device 1 uses m of the maximum number of TS outputs I). is doing.).

  Here, the detailed configuration of the broadcast signal determination unit 112 will be described with reference to FIG. As shown in FIG. 5, the broadcast signal determining unit 112 includes an unscanned broadcast signal determining unit 112a, a viewing request broadcast signal determining unit 112b, a rescan control signal transmitting unit 112c, and a priority order broadcast signal determining unit 112d. And.

  The scan unprocessed broadcast signal determining unit 112a stores the scan processed (information of the TS that has finished the scan process) and the scan unprocessed broadcast signal of the receiving device 3 that has transmitted the scan process control signal, and the scan unprocessed broadcast. The broadcast signal to be output is determined from the signals. In this embodiment, the TS id (TS identifier) for which the scanning process has been completed is stored.

  The viewing request broadcast signal determination unit 112b determines a broadcast signal to be output in response to a viewing request control signal from the receiving device 3 that has not performed the scanning process and the receiving device 3 that has not transmitted the scan processing control signal. .

  The rescan control signal transmission unit 112c delays the broadcast signal that has not been scanned by the receiving apparatus 3 by the time required for the scanning process so that the receiving apparatus 3 that has transmitted the scan processing control signal performs the scanning process. The rescan control signal is transmitted to the control signal transmitting / receiving unit 12. The time required for the scanning process is obtained by storing in advance the time required for the receiving apparatus 3 to perform the scanning process. The time required for this scanning process is also used when the broadcast signal determining means 112 grasps the end of the initial scan or rescan.

  The priority order broadcast signal determination unit 112d determines in advance the broadcast signal output by the signal selection unit 11 when a plurality of reception devices 3 are provided (a plurality of reception devices 3 that output broadcast signals exist). It is determined according to the priority order. That is, by setting the priority order for outputting the broadcast signal in the receiving device 3 in advance, the broadcast signal can be output according to this priority order.

FIG. 6 shows a flowchart of the scan processing operation of the selective transmission apparatus 1.
Hereinafter, along the flowchart of FIG. 6, a processing operation in which the selective transmission device 1 performs a scanning process on the reception device 3 will be described.

  In step S101, the reception device remote controller 32 of the reception device 3 transmits an initial scan or rescan request to the selective transmission device 1 in order to obtain a receivable frequency table. This initial scan or rescan request (request command) is sent to the broadcast signal determination means 112 via the control signal transmission / reception unit 12 of the selective transmission apparatus 1. At the same time, the request command is also received by the receiving device main body 31 of the receiving device 3, and the receiving device main body 31 starts a scanning process.

  Next, in step S102, when there are a plurality of receiving apparatuses 3, the signal selecting unit 11 of the selective transmitting apparatus 1 is a TS that is being viewed by a receiving apparatus 3 other than the receiving apparatus 3 that has transmitted an initial scan or rescan request. Know a few meters. As a result, the number of output TSs that can be used for the scanning process, that is, the maximum number of TSs I that can be output by the selective transmission device 1 is reduced by the number of TSs m that other receiving devices 3 are viewing (I−m). ) Is calculated. When there is one receiving device 3, I = 1 and M = 0, and always Im = 1.

  Here, if I−m = 0, the process proceeds to step S <b> 107, and the signal selection unit 11 of the selective transmission device 1 is viewing the reception device body 31 of the reception device 3 and the other reception device 3. Wait for the scanning process of m TSs to finish. In this case, “m” = “I”.

  If I−m> 0, the process proceeds to step S103. Here, when the number of output TSs that can be used for the scanning process is 1 or more (I−m ≧ 1), the signal selection unit 11 of the selective transmission apparatus 1 includes the TS that has not been scanned by the receiving apparatus that has made the scan request. (I−m) TS are determined and output. When the number of unprocessed TSs is less than (I−m), that number of unprocessed TSs is output.

  In step S104, the signal selection unit 11 scans the receiving device body 31 of the receiving device 3 with a maximum of (I−m) TS and m TSs that other receiving devices were viewing. Wait for the process to finish.

  In step S <b> 105, the signal selection unit 11 of the selective transmission device 1 temporarily stops (I−m) TS outputs for scanning after the scanning process of the reception device main body 31 of the reception device 3 is completed.

In step S106, information on the receiving device 3 that has transmitted the initial scan or rescan request and the TS for which the receiving device 3 has completed the scanning process is stored, and the receiving device 3 updates the receivable frequency table. To do.
When there is one receiving device 3, the information of TS for which the receiving device 3 has finished the scanning process is stored.

  In step S108, the signal selection unit 11 of the selective transmission device 1 updates the information on the TS for which the receiving device 3 that has requested the scan has finished the scan processing, and determines whether or not an unscanned TS remains. If all the TSs have been scanned, the process ends (END). If there is an unprocessed TS, the process proceeds to step S109.

  In step S109, as in the case of step S102, the signal selection unit 11 of the selective transmission device 1 receives a reception device 3 other than the reception device 3 that has transmitted the initial scan request or the rescan request when there are a plurality of reception devices 3. Grasps the number m of TS being viewed. Then, (I−m) is calculated.

  When I−m> 0, the signal selection unit 11 of the selective transmission device 1 can output an unprocessed TS, and thus the process proceeds to step S <b> 110, where the command transmission / reception unit 12 includes the reception device body of the reception device 3. A rescan control signal (rescan command) is transmitted to 31. As a result, the receiving device body 31 of the receiving device 3 starts the scanning process.

  When I−m = 0, the process proceeds to step S111, and it is determined whether or not there is an unprocessed TS among TSs that other receiving apparatuses 3 are viewing. If there is an unprocessed TS, the process proceeds to step S110 as in the case of Im> 0.

  After step S110, if I-m> 0, the process proceeds to step S103 to enter a process of outputting an unprocessed TS. In the case of Im = 0, when there is a TS that has not been scanned in the TS that is being viewed by the other receiving device 3, the end of the scanning process of the receiving device 3 is waited in step S112.

  In step S111, when there is no unprocessed TS among TSs that other receiving apparatuses 3 are viewing, the process proceeds to step S113. Here, since I−m = 0, it is not possible to output an unprocessed TS. Therefore, it waits for a certain period of time until the receiving device 3 that is being watched switches the program, so that an unprocessed TS can be output.

  While waiting for the end of the scanning process of the receiver 3 during the process from step S101 to step S104, the process from step S101 to step S107, or the process from step S110 to step S112, the other receiver 3 When the TS being viewed is switched, the TS is not output or there is a newly output TS, and the TS is not scanned, that is, is not scanned.

For example, the maximum number of TSs that can be output by the selective transmission device 1 is I = 4, the reception device a is viewing TSα and the reception device b is viewing TSβ (m = 2), and the reception device c is added to TSα and TSβ. , TSγ, TSδ are scanned (I−m = 2).
At this time, if the receiving device a switches the program being viewed and requests TSε to be viewed (outputs a viewing request control signal), the selective transmission device 1 stops outputting TSα and outputs TSε. Since there is a possibility that the receiving device c during scanning cannot scan TSα and TSε, these TSs are not scanned.

  When the receiving device 3 makes a TS viewing request that the selective transmission device 1 does not output at that time while waiting for the scanning process of the same receiving device 3 to end, the selective transmission device 1 Since the TS cannot be output, the requested TS is not output until the scanning process of the receiving device 3 is completed.

For example, the maximum number of TSs that can be output by the selective transmission device 1 is I = 4, the reception device a and the reception device b are watching TSα (m = 1), and the reception device c adds TSβ, TSβ, TSγ, It is assumed that TSδ is scanned (I−m = 3).
At this time, even if the receiving device a switches the program being viewed and requests to view TSε, the selective transmission device cannot output TSε.
Alternatively, even if the receiving device d is turned on and TSε is requested to view, the selective transmission device 1 cannot output TSε.

In order to avoid such a situation that “the requested TS cannot be output”, it is conceivable to allow a margin for the number of outputs of the selective transmission device 1 during the scanning process. If q is the number of output TSs that are not used during the scanning process, I-q TSs are scanned at a time.
For example, in the above example, if q = 1, the receiving device c that performs the scanning process performs scanning using three outputs (Iq = 3). That is, the receiving device c scans TSβ and TSγ in addition to TSα. At this time, if the receiving device a requests to view TSε, the selective transmission device 1 can output TSε.

  Alternatively, the selective transmission device 1 can prioritize the viewing request over the scanning process, outputs the requested TSx with priority, and stops the output of the scanning TSy (TSx and TSy are not scanned) Can also be performed.

  If the process from step S109 through step S111 to step S113 is repeated several times, in order to avoid a situation where the scan process does not end indefinitely, in the state where the scan unprocessed TS remains, The scanning process may be terminated with an error as “TS and channel scan failed”.

FIG. 7 shows an example of a table of receivable frequency tables (TS list: broadcast signal list) acquired by a certain receiving apparatus 3 that has made a scan request when there are a plurality of receiving apparatuses 3. The TS list includes a TS identifier (TS id), a service identifier (service id) indicating the content of a program transmitted by the TS, and a corresponding channel.
As shown in FIG. 7, it is assumed that the number of TSs to be scanned is M of the total number of TSs transmitted to the selective transmission device 1.

Broadcast signals are output from the selective transmission device 1 to the plurality of reception devices 3, and some of these reception devices 3 receive a total of m TSs, and the scanning for these has been completed. It shall be. If the number of TSs that can be output simultaneously by the selective transmission apparatus 1 is I, the number of TSs that can be output at one time for scanning is (I−m).
For this reason, the M-m TS is repeatedly scanned (I−m) at a time, and the scan ends when k (I−m) ≧ M−m in the k-th scan. To do.
As a result, a receivable frequency table as shown in FIG. 7 is created in the receiving device 3 by scanning.

  In the above embodiment, the signal received and output by the selective transmission apparatus 1 is an ISDB-T signal for digital terrestrial broadcasting. However, other than that, the broadcast signal is different from the MPEG-2 TS for digital broadcasting. A case where the transmission is performed by a transmission method, a baseband MPEG-2 TS, or a baseband MPEG-2 TS converted into an IP packet sequence may be considered.

When such a broadcast signal is directly transmitted by the transmission device, and the ISDB-T signal output from the transmission device is once received by a device called a re-transmission device, converted into another transmission method, and then transmitted to the selected transmission device. Both cases are considered when retransmitting.
In such a case, it is conceivable that the receiving device 3 uses a device corresponding to each transmission method. If this receiving apparatus 3 has a function equivalent to the above-mentioned “rescan”, the present invention can be applied to obtain the effect regardless of the transmission method. For example, a receiving apparatus corresponding to the ISDB-T format of digital terrestrial broadcasting can easily perform scan processing by applying the present invention.

  Furthermore, a method of preparing a transmission format conversion device (not shown) behind the selective transmission device 1 is also conceivable so that a reception device compatible with the ISDB-T format can be used. Such a conversion device is a device that converts an input broadcast signal into a transmission method corresponding to a connected reception device and outputs the broadcast signal on a fixed channel for each broadcast signal.

1 is a block diagram of an embodiment of a broadcast system to which a selective transmission device of the present invention is applied. It is explanatory drawing which shows the transmission-and-reception system of the control signal for the scanning process of the receiver which is exchanged between the selective transmission apparatus of this invention, and a receiver, and the control signal for program viewing. It is a functional block diagram of a 1st embodiment of a selective transmission device of the present invention. It is a functional block diagram of 2nd Embodiment of the selective transmission apparatus of this invention. It is the functional block diagram which showed the broadcast signal determination means of the selection transmission apparatus in detail. It is a flowchart of the scanning process operation | movement of the selective transmission apparatus of this invention. It is explanatory drawing which shows an example of the table | surface of the receivable frequency table which a receiver acquires by the scanning process of the selective transmission apparatus of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Selection transmission apparatus 2 Transmission apparatus 3 Reception apparatus 11 Signal selection part 12 Control signal transmission / reception part 31 Reception apparatus main body 32 Reception apparatus remote control 111 Broadcast signal list acquisition means 112 Broadcast signal determination means 113 Broadcast signal selection means 114 Broadcast signal grasping means during viewing 121 Scan processing control signal transmission / reception means 122 Viewing control signal transmission / reception means 123 Signal relay means

Claims (7)

A selective transmission device that transmits the selected broadcast signal to a reception device that outputs a broadcast signal selected from a plurality of received broadcast signals as a broadcast program,
A scan process control signal for executing a scan process for holding a list of broadcast signals in which the plurality of broadcast signals are associated with channels specified by frequencies at which each broadcast signal is received in a storage unit in the receiving device; and receiving to Rutotomoni receives a viewing request control signal for viewing request for the broadcast program from the reception apparatus control signal transceiver from the receiving device,
Based on the scanning process control signal received by the control signal transmission / reception unit, the broadcast signal that has not been subjected to the scanning process among the plurality of received broadcast signals is sequentially output to the receiving device, and the received plurality of received signals A signal selection unit that selects a broadcast signal based on the viewing request control signal from the broadcast signal and outputs the selected signal to the receiving device ; and
The signal selector is
Broadcast signal determining means for determining a broadcast signal to be output;
Broadcast signal selection means for selecting and outputting the broadcast signal based on the determination of the broadcast signal determination means,
The broadcast signal determining means includes
Scan unprocessed broadcast signal determining means for storing a scan processed and unscanned broadcast signal of the receiver that has transmitted the scan processing control signal and determining a broadcast signal to be output from the unprocessed broadcast signal;
In order to cause the receiving apparatus that has transmitted the scan processing control signal to perform the scanning process, the receiving apparatus obtains the scanning process by delaying the broadcast signal that has not been scanned by the time required for the scanning process. And a rescan control signal transmitting means for transmitting a rescan control signal for updating the broadcast signal list to the control signal transmission / reception unit . The signal selector is
When the scan processing control signal received by said control signal reception unit is input, the corresponding scan processing control signal from the scan processing control signal corresponding to the receiving device respectively held in advance, before Symbol rescan Output as a control signal to the control signal transmitting and receiving unit,
The control signal transmitting / receiving unit
The selective transmission apparatus according to claim 1, wherein the rescan control signal is output to the reception apparatus. The signal selector is
Broadcast signal list acquisition means for acquiring the broadcast signal list by collecting channels identified by an identifier and a frequency attached to each of the plurality of broadcast signals received ,
The broadcast signal determining means includes
Based on the viewing request control signals received from the control signal reception unit, according to claim 1 or claim 2, characterized in that it comprises a viewing request broadcast signal determination means for determining a broadcast signal output from the broadcast signal list Signal selection device. The signal selector is
When a plurality of receiving devices are connected to the selected transmitting device, the receiving device that is not currently performing the scanning process grasps the broadcast signals that are being viewed and obtains the total number of the broadcast signals that are being viewed. equipped with a,
The broadcast signal determining means is a broadcast that is output for the scan processing, with the maximum number obtained by subtracting the total number acquired by the viewing-and-listening broadcast signal grasping means from the maximum number of broadcast signals that can be output simultaneously by the selective transmission device. selected transmission device according to any one of claims 1 to 3, characterized in that to determine the signal. The viewing request broadcast signal determining means includes
According to claim 3, wherein the benzalkonium to determine the broadcast signal in response to said view request control signal output from the receiver not transmitting the not performed a scan process and the scan processing control signal Selective transmission device. The broadcast signal determining means includes
4. The priority order broadcast signal determination means for determining a broadcast signal output from the signal selection unit according to a predetermined priority when there are a plurality of the reception devices. Selective transmission device. The broadcast signal determining means includes
The selective transmission apparatus according to claim 3, wherein transmission of the rescan control signal is repeated until there is no unprocessed broadcast signal.

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