WO2003045059A1

WO2003045059A1 - Settop box system for cable television

Info

Publication number: WO2003045059A1
Application number: PCT/JP2001/010209
Authority: WO
Inventors: Tadashi Saitoh; Jun Tozawa
Original assignee: Renesas Technology Corp.
Priority date: 2001-11-22
Filing date: 2001-11-22
Publication date: 2003-05-30
Also published as: JPWO2003045059A1

Abstract

A STB system for a CATV in which an STB device can be freely disposed in the home a home cable to the STB device can be omitted, and therefore the cost of installing the STB device in the home can be reduced. The STB system for CATV comprises an AP device (1) connected with a coaxial cable for receiving a video signal distributed through the coaxial cable, and an STB device paired with the AP device and connected with a television for outputting a video signal to the television. The AP device (1) and the STB device are inter connected by a wireless signal to multiplex and transmit/receive the video signal and control data for managing the customer audience. The AP device (1) is provided with a wireless processing unit composed of a wireless MAC circuit (8), a wireless PHY circuit (9), a wireless RF circuit (10) and an AP device controlling CPU (19). The STB device is also provided with a wireless processing unit having a similar construction. Wireless information is communicated between the AP device (1) and the STB device.

Description

Set-top box system for cable TV

The present invention relates to an information transmission technology for a cable television (CATV), and more particularly to a set-top pod for wirelessly transmitting and receiving video signals.

This technology relates to technology that is effective for use in field equipment, access point equipment, and set-top boxes (STB: Set Top B0) systems for CATV. Background art

According to the studies made by the present inventors, the following technologies can be considered for the information transmission technology for CATV.

For example, home-use CATV STB equipment can be converted to analog or digital television (through a coaxial cable routed to each home), as shown in the “Op en Cable STB” standardized by the US Cable Lab. TV: te 1 evision) signals are distributed to homes, and at the same time, customer viewing management information is transmitted and received between each home and the base station through another frequency band (OOB: Out Of Band).

Further, as an STB device studied by the present inventor as a premise of the present invention, for example, there is a technique as shown in FIG. FIG. 11 shows a configuration example of an STB device on which the present invention is based.

The STB device 35 which is a premise of the present invention includes a FAT tuner (FAT Tuner) 2, an AD converter (ADC) 3, a QAM demodulator (QAM Demod.) 4, and a FEC decoder (FEC Eco d.). 5, Switch 6, O OB tuner (11), AD converter (ADC) 12, QP SK demodulator (QPSKD emo d.) 13, FEC decoder (FEC D eco d.) 14, MAC circuit for OOB (OOB MAC) 15, DA converter (DAC) 16, QPSK modulator (QPSK Mod.) 17, POD interface (POD I / F) 18, POD 20, ECC generator for POD (ECC Enc.) 21, CPU22 for POD control, descrambler (Desc.) 23, demultiplexer (TS DMUX) 30, video decoder (Video Decoder) ) 31 1, Audio Decoder 32, Selector (Se 1.) 36, Video output terminal 37, Audio output terminal 38, STB device control CPU 60, etc.

In this STB device 35, a TV signal is distributed to the STB device 35 installed in the home by a coaxial cable 45 wired to the home, and the STB device 35 outputs a video signal and an audio signal. These are connected to a TV (not shown) from the video output terminal 37 and the audio output terminal 38 so that the viewer can enjoy the TV program. The TV signal is transmitted by a FAT (Forward R Appl icat tiOnTran ssport) channel. As a modulation method, an analog modulation method such as NTSC or a digital modulation method such as MPEG-TS (MPEG TransportStream) is used.

The FAT tuner 2 selects the FAT channel. If the selected channel uses the analog modulation method, the analog TV signal 43 is input to the selector 36 as it is, and the video output terminal is used as a video signal and audio signal. 37, output from audio output terminal 38. The selector 36 switches the output according to the modulation method. In the case of the digital modulation method, the digital TV signal 44 is demodulated into a digital signal by the AD converter 3 and the QAM demodulator 4, and further subjected to error correction processing by the FEC decoder 5, and then the POD input. It is input to POD (Point Of Deployment) 20 via evening face 18. In POD 20, the descrambler 23 descrambles the data and returns the data again to the STB device 35 via the POD interface 18.

The switching switch 6 is for switching the digital modulation type TV signal. When the POD 20 is installed, the signal switched by the POD 20 is output. When the POD 20 is not installed, the signal is switched. The signal before being scrambled is input to the demultiplexer 30 of the MPE G-TS. The demultiplexer 30 separates the video signal and the audio signal from the digitally modulated TV signal, Input to audio decoder 31 and audio decoder 32. The video decoder 31 decodes the video signal coded (compressed) by the MPEG system and outputs it to the selector 36. The audio decoder 32 decodes the audio signal encoded (compressed) by the MPEG method or the AC-3 method, and outputs the decoded signal to the selector 36.

The data for customer control, which is different from the TV signal, is used for various controls for customer viewing management. The frequency band (OOB) different from the FAT channel is used for the base station (not shown) and the STB installed in each home. Transmitted and received between devices 35. Information such as program information and billing control sent from the base station to the STB unit 35 is selected by the OOB tuner 11, and then converted to digital data by the AD converter 12 and QPSK demodulator 13. , And error correction is performed by the FEC decoder 14. The output of the FEC decoder 14 is input to the POD 20 via the POD interface 18 and to the OOB MAC circuit 15. In the POD 20, the CPU 22 for the POD control that performs the charging control takes in the control data and uses this data for the charging control.

On the other hand, the data input to the OOB MAC circuit 15 is used to control the entire STB device 35 after only necessary data is selected by the OOB MAC circuit 15. Input to CPU 60. Based on this information, the STB device control CPU 60 performs a reception application process for a pay broadcast according to a viewer's selection. In this process, specifically, data communication is performed between the CPU 60 for controlling the STB device and the CPU 22 for controlling the pod, and a request for viewing a pay broadcast is sent to the CPU 22 for controlling the pod. The PDU control CPU 22 sends pay broadcast viewing information to the base station, and also controls the descrambler 23 to descramble the digitally modulated TV signal to enable pay broadcast viewing. The pay broadcast viewing information is sent to the QPSK modulator 17 via the POD interface 18 after adding an error correction code for the 00 (:( :: generator 21, and the coaxial cable 45. The signal is converted into a modulated signal that can be transmitted through the D / A converter and further converted into an analog signal by the DA converter 16 and input to the OOB tuner 11.

By the way, as a result of the study of the above-mentioned STB apparatus by the present inventors, the following has become clear.

For example, the STB device described above uses the same coaxial cable to Not only can it transmit and receive data for various types of customer viewing control, it is an excellent system that can provide users with high-performance services with an inexpensive system configuration. However, since all information is sent via cables, cable wiring is indispensable to add STB equipment. In other words, in order to add the second and subsequent STB devices in the same home, installation of new cables up to the room where the second or third STB device or TV is installed in the home is necessary. Usually, most of the cable to each home is already wired, but in most cases, the wiring in the home is not performed at all, which requires a great deal of cost.

Therefore, an object of the present invention is to allow the STB device to be freely arranged in a home, and to eliminate the need to install a cable in the home up to the STB device. It is an object of the present invention to provide a CATV STB system that can reduce installation costs.

The above and other objects and novel features of the present invention will become apparent from the description of the present specification and the accompanying drawings. Disclosure of the invention

The following is a brief description of an outline of typical inventions disclosed in the present application.

That is, the STB system for CAT V of the present invention is connected to an access point (AP: Access Point) device that is connected to a cable and receives a video signal distributed through the cable, and is connected to the TV. It is divided into an STB device that outputs video signals to it, and the two are connected by wireless signals, and not only TV signals (video signals) but also data for controlling customer viewing management such as billing information. Also, by superimposing and processing the same radio signal, the wiring between the AP device and the STB device can be eliminated and the STB device can be arranged freely without impairing the advantages of the system described above. It was made.

Further, the CATV STB system of the present invention transmits a video signal with time information added thereto, and can control the reproduction timing based on the time information at the time of reception. In addition to digital modulation, analog modulation It is designed to support signals. Furthermore, by including a plurality of independent means in the AP device, it is possible to support a plurality of STB devices. Therefore, according to the CATV STB system of the present invention, the STB device can be freely arranged in the home, and the installation of a home cable up to the STB device can be omitted. Therefore, the cost of home installation can be reduced. This is remarkable when the second and subsequent STB units are added.

In addition, the present invention eliminates the need for wiring between the STB device and the AP device, so that the STB device can be carried freely at home, providing new convenience to viewers, and providing a new portable TV system. Applications can also be expected.

In particular, the present invention is effective when applied to a wireless receiving device and system for receiving a TV signal, such as a home STB device, and is similarly applied to a video reproducing device in which a display unit and a signal source are separated. It is also possible to apply. BRIEF DESCRIPTION OF THE FIGURES

1 to 5 are diagrams for explaining a CATV STB system according to the first embodiment of the present invention. FIG. 1 is a configuration diagram showing an AP device, and FIG. 2 is a configuration diagram showing an STB device. Figure 3, Figure 3 is a timing diagram showing data transfer, Figure 4 is a block diagram showing a wireless MAC circuit in the AP device, Figure 5 is a block diagram showing a wireless MAC circuit in the STB device, and Figures 6 and 7 are book diagrams. FIGS. 7A and 7B are diagrams for explaining a CATV STB system according to a second embodiment of the present invention. FIG. 6 is a configuration diagram illustrating an AP device, FIG. 7 is a configuration diagram illustrating an STB device, and FIGS. FIGS. 8A and 8B are diagrams for explaining a CATV STB system according to Embodiment 3 of the present invention. FIG. 8 is a configuration diagram showing an AP device, FIG. 9 is a timing diagram showing data transfer, and FIG. 10 is a data transfer diagram. FIG. 11 is a configuration diagram showing an STB device studied as a premise of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. In all the drawings for describing the embodiments, those having the same functions are denoted by the same reference numerals, and their repeated description will be omitted. (Embodiment 1)

A CATV STB system according to a first embodiment of the present invention will be described with reference to FIGS.

FIG. 1 shows a configuration diagram of an AP device connected to a coaxial cable in the CAT V STB system of the present embodiment. Figure 2 shows the configuration of the STB device connected to the TV.

The CATV STB system according to the present embodiment is connected to a coaxial cable as shown in FIG. 1 and receives an image signal distributed through the coaxial cable. And an STB device that is connected to a TV and outputs a video signal to the TV, as shown in FIG.

In FIG. 1, the AP device 1 according to the present embodiment, which is connected to the coaxial cable 45 and receives the video signal distributed through the coaxial cable 45, is the same as that of FIG. Compared to the STB unit 35, the MPEG decoder unit composed of the demultiplexer 30, video decoder 31 and audio decoder 32, selector 36 and CPU 60 for STB device control has a wireless MAC circuit 8, a wireless PHY It replaces the wireless processing unit consisting of circuit 9, wireless RF circuit 10, and CPU 19 for AP device control, and instead of reproducing images, data is sent as wireless information to the STB device 34 shown in Fig. 2. The difference is that the device has a function of transmitting and receiving.

That is, the AP device 1 according to the present embodiment includes a FAT tuner (FAT Tuner) 2, an AD converter (ADC) 3, a QAM demodulator (QAM Demod.) 4, and an FEC decoder (FEC D eco d.) 5, Switching switch 6, Wireless MAC circuit (WLAN MAC) 8, Wireless PHY circuit (WLAN PHY) 9, Wireless RF circuit (WLAN RF) 10, OOB tuner (OOB Tuner) 11, AD converter (ADC) 12, QPSK demodulator (QP SK Demod.) 13, FEC decoder (FEC Eco d.) 14, OOB MAC circuit (OOB MAC) 15, DA converter (D AC) 1 6, QPSK modulator (QPSK Mod.) 17, POD interface (POD I / F) 18, CPU 19 for AP device control, POD20, ECC generator for POD (ECC Enc.) 2 1, POD control CPU 22, descrambler (Desc.) 23, wireless input / output terminal 24, etc. ing. In FIG. 1, blocks having the same functions as those in FIG. 11 are denoted by the same reference numerals, and descriptions of those processes are omitted.

The AP device 1 has a FAT tuner 2 as a selecting means for selecting a desired channel from the video signals distributed through the coaxial cable 45, and a digital modulating means for digitally modulating the video signal of the selected channel. A / D converter 3, QAM demodulator 4 and FEC decoder 5, POD 20 as expansion means for descrambling digitally modulated video signals, AP device control as processing means for processing control data for customer viewing management CPU 19, wireless MAC circuit 8, wireless PHY circuit 9, and wireless RF as wireless processing means that multiplexes the descrambled video signal and control data, modulates it, converts it to a wireless signal, and transmits it. A circuit 10 and the like are provided.

In the AP device 1, the CPU 19 for controlling the AP device, which controls the entire system, is sent and received from the POD 20 via the POD interface 18 to the 008 1 ^ 8 (: circuit 15). The data signals are connected, and these are data-communicated with the CPU 33 for controlling the TB device 34 that controls the entire TB device 34 shown in Fig. 2. Input / output to / from the wireless MAC circuit 8 (g in the same figure) The wireless MAC circuit 8 is used for the output of the switch 6 (d in the same figure) and the data communication of the CPU 19 for controlling the AP device described above. The signals are connected, multiplexed on the time axis, and output to the wireless PHY circuit 9. The wireless PHY circuit 9 adds an error correction signal to the input data and modulates it (in the current case). Is 256 Q AM modulation, but similar effects can be expected with other modulation methods.) The signal is converted into a high-frequency radio signal by the F circuit 10 and output from the radio input / output terminal 24.

In FIG. 2, the STB device 34 according to the present embodiment is a device that has a receiving function paired with the AP device 1 of FIG. 1, is connected to a TV, and outputs a video signal to the TV. , Wireless input / output terminal 25, wireless RF circuit (WLAN RF) 26, wireless PHY circuit (WLAN PHY) 27, wireless MAC circuit (WL AN MAC) 28, demultiplexer (TS DMUX) 30, video decoder (Video) D ecoder) 3 1, audio decoder (Au dio decoder) 32, STB device control CPU 33, video output terminal 37, audio output terminal 38 It is composed of

The STB device 34 receives the radio signal transmitted from the AP device 1, converts it to a digital signal, selects a desired signal, and separates the video signal from the customer viewing control data. Wireless RF circuit 26 as wireless processing means, wireless PHY circuit 27, wireless MAC circuit 28 and demultiplexer 30, video decoder 3 as decoding means for decoding separated video signals and outputting them to TV 1 and an audio decoder 32, and a CPU 33 for controlling the STB device as a processing means for processing the separated control data.

In the STB device 34, the signal transmitted and received from the wireless input / output terminal 25 is converted into a baseband signal by the wireless RF circuit 26, converted into a digital signal by the wireless PHY circuit 27, and transmitted to the wireless MAC circuit. 2 Necessary data is selected according to 8. Specifically, data output from devices other than the paired AP device 1 and transferred to other devices are excluded. The wireless MAC device 28 further separates the three types of data multiplexed by the AP device 1 and inputs and outputs the data to the corresponding blocks. Specifically, the video signal (d in the figure) sent from the FAT channel, which is the output of the switching switch 6 in FIG. 1, is sent to the demultiplexer 30 and the input / output of the AP device control CPU 19 in FIG. The data (g in the figure) is input / output to the STB device control CPU 33 of the STB device 34, respectively. The functions of the video decoder 31 and the audio decoder 32 are the same as those of the respective decoders shown in FIG.

FIG. 3 shows a timing chart of wireless data transfer according to the present embodiment. In the figure, (1) is the timing of inputting video data to the wireless MAC circuit 8 of FIG. 1, (2) is the timing of data actually transmitted wirelessly, and (3) is the wireless MAC circuit of FIG. The output timings of the data from 28 are shown below.

The data in FIG. 3A is sequentially input to the wireless MAC circuit 8 in a time series in the form of a packet 70 (70-0, 70-1, 1,...). The wireless MAC circuit 8 measures the time from the reference pulse 73 generated at an interval of a fixed reference period (T), and uses this value (t—1, t1-2,...) As time information as wireless information. It is embedded in the header (hatched area 71 in the figure) added to the LAN bucket 71 (71 0, 71-1, 1,...), And the wireless communication is performed at the timing shown in Fig. 3 (2). To send. The data sent over the air The data is transmitted and received by the STB device 34, processed by the wireless RF circuit 26 and the wireless PHY circuit 27, and then input to the wireless MAC circuit 28. As shown in Fig. 3 (3), the wireless MAC circuit 28 obtains the embedded timing information from the wireless LAN header of the received packet and obtains the corresponding bucket 72 (72-0, 7). Adjust the output timing of 2-1, · · ·). Therefore, the packet 70 containing the video data input to the wireless MAC circuit 8 is delayed as a fixed time (2T in FIG. 3) and output as a packet 72 at the same time interval.

In FIG. 3, reference numeral 73 denotes a wireless LAN reference pulse (beacon pulse), based on which the transmission / reception timing of various data is determined. In the figure, 71-cU is a dummy packet for which the corresponding packet did not happen to be sent, and can be omitted. In the drawing, 75 (75-1, 75-2,...) Indicates data transmitted from the CPU 19 of the AP device 1 to the CPU 33 of the STB device 34. 74 (74-1, 74-2,-...) Is data transmitted from the CPU 33 of the STB device 34 to the CPU 19 of the AP device 1. These data have a problem in the system if they are extremely delayed, but they have little significance in timing, and it is not necessary to add timing information such as the data in packet 71. In the example of FIG. 3, the data 74 and 75 are transmitted as a pair, but it is not always necessary to form a pair, and data transmission and reception are performed at a predetermined timing.

FIG. 4 is a block diagram at the time of data transmission of the wireless MAC circuit 8 according to the present embodiment.

The wireless MAC circuit 8 according to the present embodiment includes a packet input terminal 80, an input interface (Input I / F) 81, an input buffer (Buffer) 82, a bucket processing circuit (Packack). ) 83, Link control circuit (Link) 84, Reference pulse generation circuit (PG) 88, Timer (Timer) 85, Latch circuit (Latch) 86, Output terminal 87 It is configured. .

In this wireless MAC circuit 8, when a packet is input from the bucket input terminal 80, the latch circuit 86 holds the value of the timer 85 at that time by a start signal from the input interface 81. Send this data to the input buffer 82. The packet processing circuit 83 starts to operate the header and packet of the wireless LAN from these data. The contents are composed, sent to the link control circuit 84, and output from the output terminal 87. In practice, a processing delay is inevitable between the transmitting side and the receiving side, so a value obtained by adding the offset value for the processing delay to the value of the timer 85 is used. The reference pulse of the wireless LAN is generated by a reference pulse generation circuit 88, and the timing of transmission and reception of various data is determined based on the reference pulse.

FIG. 5 is a block diagram when data is received by wireless MAC circuit 28 according to the present embodiment.

The wireless MAC circuit 28 according to the present embodiment includes an input terminal 90, a link control circuit (Link) 91, a timer 92, and a packet processing circuit (Un-Pack) 93. It consists of a buffer 94, an output interface 95, a comparator 96, and a bucket output terminal 97.

In the wireless MAC circuit 28, the packet data input from the input terminal 90 is processed by the link control circuit 91, and then the header as a wireless LAN is processed by the packet processing circuit 93. Then, the timing information is transferred to the output buffer 94. The comparator 96 compares the timing information in the output buffer 94 with the value of the timer 92 in the link control circuit 91, and sends a start signal to the output interface 95 when they match. The output interface 95 starts outputting the packet in the output buffer 94 from the bucket output terminal 97 after receiving the start signal.

As described above, according to the CATV STB system of the present embodiment, the AP device 1 that is connected to the coaxial cable 45 and receives the video signal distributed through the coaxial cable 45 and the TV, It is divided into a STB device 34 that is connected and outputs a video signal to this TV, and the two are connected by a wireless signal, and not only video signals but also customer viewing management such as billing information The control data is also superimposed on the same radio signal and processed, so that the STB device can be changed without changing the charging control method used in the base technology of the present invention or the device such as the POD 20. The device 34 can be installed and moved to an arbitrary position in the home, so that portability can be achieved without changing existing devices, and user convenience is improved. Further, the wiring work for the second and subsequent units required in the base technology of the present invention becomes unnecessary, Construction costs can be reduced.

Also, although the video data is transmitted as a wireless signal, the information itself of the POD 20 that performs the charging control is not transmitted wirelessly except for the communication information with the CPU 33 of the STB device 34, and a more secure Information management is possible. The data transmitted from the POD 20 to the base station via the cable has the same configuration as that of the base technology of the present invention, and can be transmitted at the same timing as the base technology of the present invention. POD 20 and its peripheral circuits and control software No changes to clothing are required.

(Embodiment 2)

Second Embodiment A CAT V STB system according to a second embodiment of the present invention will be described with reference to FIGS.

FIG. 6 shows a configuration diagram of an AP device connected to a coaxial cable in the CAB STB system of the present embodiment. FIG. 7 shows a configuration diagram of an STB device connected to a TV.

The STV system for CATV according to the present embodiment is connected to a coaxial cable as shown in FIG. 6, and receives an image signal distributed through the coaxial cable. As shown in Fig. 7, it consists of an STB device connected to a TV and outputting a video signal to the TV, as shown in Fig.7.

In FIG. 6, the AP device 48 connected to the coaxial cable 45 according to the present embodiment and receiving the video signal distributed through the coaxial cable 45 is different from the AP device 1 according to the first embodiment described above. The difference is that the FM modulator 49 is newly installed and the signal is input to the wireless RF circuit 51 of the wireless LAN.

That is, the AP device 48 according to the present embodiment includes a FAT tuner (FAT Tuner) 2, an AD converter (ADC) 3, a QAM demodulator (QAM Demod.) 4, and an FEC decoder (FEC D eco d.) 5, Switching switch 6, FM modulator (FM Mod.) 49, Wireless MAC circuit (WLAN MAC) 64, Wireless PHY circuit (WLAN PHY) 9, Wireless RF circuit (WLAN RF) 51 1, OOB tuner (OOB) Tuner) 1 1, AD converter (ADC) 1 2, QPSK demodulator (QP SK Demod.) 13 3, FEC decoder (FEC D eco d.) 14, OOB MAC circuit (OOB MAC) 1 5, DA converter (DAC) 16 QPSK modulator (QP SK Mod.) 17, POD interface (POD I / ¥) 18, CP 53 for AP device control, POD20, ECC generator for POD (ECCE nc. ) 21, CPU 22 for pod control, descrambler (Desc.) 23, wireless input / output terminal 52, etc. The AP device 48 is additionally provided with an FM modulator 49 as analog processing means for converting an analog-modulated video signal into a wireless signal and transmitting the signal.

In the AP device 48, the FM modulator 49 is a circuit that FM-modulates the analog TV signal 43 sent through the FAT channel and converts it into an RF signal.

When the analog TV signal 43 of the FAT channel is selected by the viewer, that channel is selected by the FAT tuner 2, and since the signal is an analog TV signal, the signal does not pass through the circuit after the AD converter 3 The signal is input to the wireless RF circuit 51 of the wireless LAN via the FM modulator 49. In that case, the wireless MAC circuit 64 multiplexes only the input / output data (g in the figure) of the CPU 53 and does not multiplex the data of the digital channel (d in the figure). The wireless MAC circuit 64 receives a TV signal synchronizing signal from the FM modulator 49, and transmits data according to a time slot (VBI: Video Blanking Interval) during which the TV signal is not used. 9, and the wireless communication circuit 9 outputs the signal to the wireless RF circuit 51. The wireless RF circuit 51 switches between an analog TV signal sent from the FM modulator 49 and data sent from the wireless PHY circuit 9 in accordance with a synchronization signal of the TV signal. In this case, the TV signal 44 of the digital channel is not selected by the radio RF circuit 51, but passes through the AD converter 3, the QAM demodulator 4, and the FEC decoder 5, as in the first embodiment. And perform the same processing.

In FIG. 7, an STB device 54 according to the present embodiment is an STB device that is paired with the AP device 48 of FIG. 6 and is connected to a TV and outputs a video signal to the TV. The difference from the first embodiment is that the selector 36 switches between the analog channel TV signal 43 and the digital decoder TV signal 44 reproduced by the video decoder 31 and the audio decoder 32. That is to say. That is, the STB device 54 according to the present embodiment includes a wireless input / output terminal 59, a wireless RF circuit (WLAN RF) 56, a wireless PHY circuit (WLAN PHY) 27, a wireless MAC circuit (WLAN MAC) 65, Multiplexer (TS DMUX) 30, Video decoder (Video decoder) 31, Audio decoder (Audio decoder) 32, STB device control CPU55, Selector 36, Video output terminal 37, It consists of audio output terminals 38 and so on. The three-cable device 54 is provided with a selector 36 as analog processing means for selecting a radio signal of analog modulation and outputting the signal to the TV. In this STB device 54, the radio RF circuit 56 When the analog channel is selected, an analog TV signal 43 is output. During the VBI period, communication is performed between the AP device control CPU 53 of FIG. 6 and the STB device control CPU 55 of FIG. Data is output. The data sent from the CPU 55 that controls the STB device 54 to the CPU 53 that controls the AP device 48 is synchronized with the analog TV signal 43 by the wireless MAC circuit 65, and the VTB period is used for the STB device. Sent from 54 to AP device 48.

Therefore, the STB system for CAT V according to the present embodiment has an advantage that the same service as that of the digital modulation method can be provided even for the TV signal of the analog modulation method. Of course, the same advantages as those of the first embodiment can also be realized.

(Embodiment 3)

Third Embodiment A CAB STB system according to a third embodiment of the present invention will be described with reference to FIGS.

FIG. 8 shows a configuration diagram of an AP device connected to a coaxial cable in the CATV STB system of the present embodiment.

The STB system for CAT V according to the present embodiment includes an AP device that is connected to a coaxial cable and receives a video signal distributed through the coaxial cable, as shown in FIG. A pair is formed by pairs n (a number of 2 or more (1 is also possible)) and is composed of a plurality of STB devices as shown in FIG. 2 of the first embodiment.

In FIG. 8, the coaxial cable 45 according to the present embodiment The AP device 57, which receives the video signal distributed via the cable 45, has a plurality of receivers 58 installed compared to the AP device 1 of the first embodiment and the AP device 48 of the second embodiment. The difference is that a common wireless MAC circuit 63, a common wireless PHY circuit 9, and a common wireless RF circuit 10 are provided for the plurality of receiving units 58. In the figure, the receiving section 58 is composed of three sets (58-1, 58-2, 58-3), but the number is not limited to three and may be any number. Also, only one set may be installed in the initial state, and a new one may be added each time an STB device is added. That is, the AP device 57 of the present embodiment includes a plurality of receiving units 58 (58-1, 58-2, 58-3), a wireless MAC circuit (WLAN MAC) 63, and a wireless PHY circuit ( WL PHY) 9, wireless RF circuit (WLAN RF) 10, wireless input / output terminal 24. Each receiving section 58 includes a FAT tuner (FAT Tuner) 2, an AD converter (ADC) 3, a QAM demodulator (QAM Demod.) 4, an FEC decoder (FECD eco d.) 5, and a switching switch 6. , Demultiplexer (TS DMUX) 61, OOB tuner (OOB Tuner) 11, AD converter (AD C) 12, QP SK demodulator (QP SKD emo d.) 13, FEC decoder (FECD eco d.) 14, MAC circuit for OOB (OOB MAC) 15, DA converter (DAC) 16, QPSK modulator (QP SK Mod.) 17, P OD interface (P OD I / F) 18, AP device control CPU 62, POD 20 (including EOD generator 21 for POD, CPU 22 for POD control, descrambler 23), etc.

In the AP device 57, unlike the AP device 1 of the first embodiment shown in FIG. 1, a demultiplexer 61 for selecting digital channel data is provided after the output of the switching switch 6. The demultiplexer 61 is the only video that is actually selected and viewed by the viewer at the time, from among multiple video signals multiplexed on the same digital channel and the accompanying data. It works by selecting only the signal and its accompanying data packets, and discarding other packets. Therefore, the output of the demultiplexer 61 can greatly reduce the amount of data compared to its input. In the wireless MAC circuit 63, the video signals (h-1, h-2, h-3) from the plurality of receiving sections 58 (58-1, 58-2, 58-3) are provided. And control data (g-1, g-2, g-3) are multiplexed and sent to the wireless PHY circuit 9, and the data is transmitted to the wireless RF circuit 10 and finally the wireless signal Is output from the wireless input / output terminal 24.

FIG. 9 shows a timing chart of data transfer in the wireless LAN according to the present embodiment. (1) in the figure shows a packet 70 of video data of the first receiving unit 58-1 corresponding to h-1 in FIG. 8, and (2) and (3) in the same manner. Indicates the evening of packets 40 and 41 of the video signals (h-2 and h-3) of the second and third receiving sections 58-2 and 58-3, respectively. (4) of the figure shows the timing of the data actually transmitted by radio, and (5) shows the output timing of the data corresponding to the first receiving section 58-1 of the radio MAC circuit 28.

Each of the buckets 70 (70-0, 70-1,...-), 40 (40-0, 40-1, 1,...), In FIG. 9 (1) to (3) The data of 4 1 (4 1-0, 4 1-1, ···) is randomly generated independently of other packet data, but as a time average it is a fixed data rate that is determined in advance. Sent by For these packets 70, 40, 41, the interval from the reference pulse (peacon pulse) 73 is measured in the same manner as in the first embodiment, and as a result (t-1l, t-2) , '.', D−l, d−2,..., E−1, e−2,... ■) as wireless LAN packets 7 1 (7 1−0, 7 0−1,. ···), 46 (46-0, 46-1, · · ·), and 47 (47-0, 47-1, · · ·) headers (71, 4 6 in the figure) , 47), and transmit wirelessly at the timing shown in Fig. 9 (4). Similarly, control data exchanged between the CPU 62 of each receiving unit 58 of the AP device 57 and the CPU of the STB device is represented by 74, 75 as shown in FIG. It is transmitted and received at a predetermined time without such time information.

FIG. 10 shows these relationships in further detail of the timing of the wireless transmission in FIG. 9 (4). -'

In the figure, the packet of all video data is indicated by 7 1 (71-η, 71-n + 1, 71-n + 2, 71-n + 3). Of the receiver 58 (58-1, 58-2, 58-3). Packets sent from any of the receivers 58 are within the area a defined by the reference pulse 73. They are sent sequentially, but the number is not necessarily constant. On the other hand, the control data is a data 75 (75-1, 75-2) transmitted from the AP device 57 to the STB device 34 at the time of the predetermined region b. At time c, data 7 4 (74-1, 74-2) sent from the STB device 34 to the AP device 57 are respectively sent. If the number of packets of the video data is too large to send in the area a, it is sent in the area of the next reference pulse 73. As mentioned earlier, the number of packets is not constant, but on average does not exceed the predetermined data rate, so if there is a sufficient margin in the wireless; LAN transfer rate, there will be some packets that cannot be transferred. It does not increase. On the other hand, data for control is not always transferred because its data rate is not always constant, and may be transferred only when necessary. Therefore, packets 74 and 75 of the wireless LAN for control data have a transfer data amount added to the header (not shown) as the wireless LAN, and when the data cannot be transferred within one area b or c, It is transferred in the next area.

In other words, when the data amount is n and only m data can be sent, m data is transferred together with a header of packet size m in the first area, and the remaining (n-m) data is It is transmitted with a packet size (nm) header. The same applies to a case in which three or more areas are covered.

In the present embodiment, in the STB device 34 of FIG. 2 corresponding to the AP device 57, for example, at the stage of the wireless MAC circuit 28, the corresponding receiving section 58, for example, 58-1 of FIG. Since only one day is selected, the subsequent processing is the same as the processing shown in FIGS. 1 and 2 of the first embodiment. However, since unnecessary packets have been destroyed by the demultiplexer 61 at the stage of the drying device 57, the amount of data input to the demultiplexer 30 of the STB device 34 has been reduced. The demultiplexer 30 is necessary because it is necessary to separate the video signal and the audio signal.

Therefore, in the STB system for CATV of the present embodiment, data for a plurality of STB devices 34 is wirelessly transmitted using one AP device 57 having a plurality of receiving units 58 and one radio frequency band. In this case, there is an advantage that the cost of the device can be reduced and the required frequency band can be reduced. Of course, the implementation The advantages shown in Embodiment 1 can also be realized.

Although the invention made by the inventor has been specifically described based on the embodiment of the invention, the invention is not limited to the embodiment and can be variously modified without departing from the gist of the invention. Needless to say, Industrial applicability

As described above, the CATV STB system according to the present invention relates to CATV information transmission technology, and is particularly useful for a CATV STB system that transmits and receives video signals wirelessly. It can be widely applied to wireless receivers and systems that receive video, and video playback devices in which the display unit and the signal source are separated.

Claims

The scope of the claims

1. An access point device that receives a video signal distributed via a cable,

A set-top box device for outputting a video signal to a television, wherein the access point device and the set-top box device are connected by a wireless signal, and a digital modulation video signal and customer viewing management are connected. 2. The cable television set-top box according to claim 1, wherein the control data is transmitted in a multiplexed manner. 2. The cable television set-top box system according to claim 1, wherein the access point device has been distributed. Selecting means for selecting a desired channel from the video signal; digital modulating means for digitally modulating the video signal of the channel selected by the selecting means; and an image digitally modulated by the digital signal modulating means A developing means for solving the scruple of the signal, and control data for the customer viewing management A first processing unit for processing, and a video signal descrambled by the expansion unit and control data processed by the first processing unit are multiplexed, modulated, converted to a radio signal, and transmitted. The set-top box device receives a radio signal transmitted from the access point device, converts the radio signal into a digital signal, selects a desired signal, and controls a video signal and customer viewing management. A second wireless processing unit that separates the control data from the control data, a decoding unit that decodes the video signal separated by the second wireless processing unit and outputs the decoded video signal to a television, and a second wireless processing unit. And a second processing means for processing the separated control data. A set-top box system for a cable television.

3. The cable television set-top box system according to claim 2, wherein the first wireless processing means of the access point device transmits the video signal with time information added thereto.

The second wireless processing means of the set-top box device controls a reproduction timing based on the time information when the video signal is received. TV set top box system.

4. The set-top box system for cable television according to claim 2, wherein the control data for customer viewing management is transmitted from the first processing means of the access point device to the second processing of the set-top box device. A set-top box system for a cable television, wherein data is transmitted and received bidirectionally from the second processing means of the set-top box device to the first processing means of the access point device.

5. The cable television set-top box system according to claim 2, wherein the video signal further includes an analog modulation system,

The access point device further includes first analog processing means for converting an analog modulated video signal into a wireless signal and transmitting the signal.

The set-top box system for cable television, wherein the set-top box device further includes a second analog processing means for selecting an analog-modulated radio signal and outputting the selected signal to a television.

6. The cable television set-top box system according to claim 5, wherein, when transmitting and receiving the video signal of the analog modulation system, the control data for the customer viewing management is transmitted and received during a VBI period. Set-top box system for TV.

7. The set-top box system for a cable television according to claim 2, wherein the access point device includes a plurality of independent selecting units, the digital modulating unit, the expanding unit, and the first processing unit,

A set-top box system for cable television, which is paired with a plurality of the set-top box devices.

8. An access point device that receives a video signal distributed through a cable,

The access point device includes: a selection unit that selects a desired channel from the distributed video signals; a digital modulation unit that digitally modulates a video signal of a channel selected by the selection unit; Expansion means for descrambling the video signal modulated by the digital modulation means, and First processing means for processing the control data, the video signal descrambled by the expansion means and the control data processed by the first processing means, multiplexed, converted into a radio signal, and transmitted. An access point device characterized by including a first wireless processing unit that performs the operation.

9. The access point device according to claim 8,

The access point device further comprises first analog processing means for converting an analog-modulated video signal into a radio signal and transmitting the signal.

10. The access point device according to claim 8,

The access point device, wherein the access point device includes a plurality of independent selecting means, the digital modulating means, the expanding means, and the first processing means.

1 1. A set-top box device for outputting a video signal to a television, wherein the set-top box device receives a transmitted wireless signal, converts the signal into a digital signal, and selects a desired signal. A second wireless processing unit that separates the video signal from the control data for customer viewing management, and a decoding unit that decodes the video signal separated by the second wireless processing unit and outputs the decoded video signal to a television. And a second processing means for processing the control data separated by the second wireless processing means.

1 2. The set-top box device according to claim 11,

The set-top box device further comprises a second analog processing means for selecting an analog-modulated radio signal and outputting the signal to the television.