JP4192326B2 - Receiving apparatus and method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a receiving apparatus and method applicable to data communication using, for example, a one-way transmission line of a satellite line.
[0002]
[Prior art]
Recently, digital communication networks have been established and various services have been started. In-house information systems using satellite links or the like are being put into practical use as one of digital communication networks. A receiver used in such a system is called a satellite intranet receiver, and makes use of e-mail, electronic news, an electronic bulletin board, etc. on TCP / IP by utilizing Internet technology.
[0003]
The satellite intranet receiver receives a transport stream supplied via a satellite line, separates a desired channel from each channel multiplexed in the stream, and descrambles the transport stream. It has a function of separating and extracting a predetermined packet from the stream and a function of distributing the obtained packet to terminals in the network.
[0004]
Possible causes of a packet not coming up from a one-way line such as a satellite line are transmission suspension, communication failure, and hang-up of a one-way line interface. The present invention is intended to recover communication from those caused by the receiving device, such as hang-up of the one-way line interface, failure of initialization at the time of starting the receiving device, and the like.
[0005]
[Problems to be solved by the invention]
If the interface goes into a hang-up state, there is no warning and communication is suddenly interrupted. In the case of a communication failure, if the receiver has a display board, the cause can be determined by looking at it. However, interface hangup cannot be determined from the outside, and a great deal of time is required to elucidate the cause. Also, when the interface is hung up, there is no other way but to restart the receiver itself. Since it takes about 2 to 3 minutes to restart, it takes 5 minutes or more to return to normal operation from the occurrence of a hang-up, even if the cause elucidation time is not included. Furthermore, when the receiver is activated, if the radio wave cannot be received due to a communication failure or the like, the interface cannot be initialized. Therefore, even if the radio wave can be normally received after that, the interface cannot be activated, and the packet cannot be received.
[0006]
Accordingly, an object of the present invention is to provide a receiving apparatus and method capable of solving the above-mentioned problems caused by the receiving apparatus such as interface hang-up and interface initialization failure.
[0007]
[Means for Solving the Problems]
In order to solve the above problems, the invention of claim 1 is a front end unit that performs descrambling by selecting a desired signal from among signals received by an antenna,
An interface for separating packets from the transport stream from the front end ;
A display unit for displaying whether or not the reception state is normal;
A control unit to which packets separated by the interface are supplied ,
The control unit detects an interface hang-up by detecting a plurality of times that a periodically transmitted packet is not supplied from the interface,
Control unit, inter - when detecting hang face, interface - the face initializing a receiving apparatus to reconfigure parameters.
[0008]
According to the third aspect of the present invention, a desired signal is selected from signals received by an antenna and demodulated, and a descrambling front end unit and a packet for separating packets from a transport stream from the front end unit In a receiving method in a receiving apparatus comprising an interface, a display unit for displaying whether or not a normal reception state is present, and a control unit to which a packet separated by the interface is supplied,
Receiving a packet periodically transmitted by the antenna and the front end unit, and supplying the received packet to the control unit;
Detecting a hangup of the interface by detecting multiple times by the control unit that a packet is not supplied from the interface ;
Inter - when detecting hang face, the control unit, interface - the face initializes a reception method and a step to reconfigure parameters.
[0009]
In the present invention, when a packet that should be periodically received according to the communication protocol is not received for a predetermined time, it is determined as a timeout. Thereby, the interface unit is restarted.
[0010]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the overall configuration of an embodiment of the present invention. As shown in FIG. 1, the receiving apparatus according to the present invention includes a receiving antenna 1, a receiver 2, and personal computer groups 11 to 1n each including n personal computers.
[0011]
A radio wave signal transmitted from the transmission device is received by the receiving antenna 1 via the communication satellite. A receiver 2 is connected to the receiving antenna 1. The receiving antenna 1 is provided with an LNB (Low Noise Block down converter). The received signal is frequency-converted into a predetermined intermediate frequency signal, and this output is supplied to the receiver 2.
[0012]
The receiver 2 selects and demodulates one carrier wave from the received signal, and descrambles a predetermined stream from the multiplexed transport stream, and is input from the front end unit 3 A one-way line interface 4 that creates a private section from a transport stream, a control unit 6 that extracts an IP packet from a private section obtained by the one-way line interface 4 and performs necessary processing, and obtains the obtained packet as a terminal device The bi-directional line interface 5 distributed to the personal computer groups 11 to 1n functioning as a display unit 7 is configured.
[0013]
The control unit 6 controls the entire receiver 2. Each of the one-way line interface 4 and the bidirectional line interface 5 is connected to the control unit 6 via a data bus, and data can be exchanged bidirectionally with each unit. Control information from the control unit 6 is supplied to each unit to control the receiver 2. The control unit 6 is connected to a display unit 7 made of, for example, a liquid crystal display panel, and displays a reception state and the like. Specifically, when the receiver 2 is in a normal reception state, a service ID corresponding to a channel in television broadcasting is displayed on the display unit 7. Further, “−−−” is displayed when radio waves cannot be received due to communication failure.
[0014]
Further, the control unit 6 determines whether or not a predetermined packet is periodically received in a predetermined communication protocol (DTCP), and automatically resets the one-way line interface 4 based on the determination result. DTCP is one of the main protocols of UDLR, which is a route control technique suitable for a network having a one-way line such as a satellite line on the way. DTCP is necessary as judgment information for the receiving apparatus to know the state of the transmitting station and to switch the network from a satellite line as a one-way line to a ground line such as a telephone line as a two-way line if necessary. .
[0015]
The front end unit 3 includes, for example, a tuner circuit, a demodulation circuit, and an error correction descrambler circuit. The front end unit 3 selects a predetermined carrier wave based on control information from the control unit 6 and performs a demodulation process corresponding to the modulation process performed on the transmission side, and responds to the encoding process performed on the transmission side. Perform error correction processing. The front end unit 3 performs descrambling processing when scrambling processing is performed on the transmission side based on control information from the control unit 6. The obtained descrambled transport stream is supplied to the one-way line interface 4.
[0016]
The one-way line interface 4 includes, for example, a demultiplexer that separates multiplexed transport streams and configures a private section from the separated transport streams.
[0017]
The private section obtained by the one-way line interface 4 is supplied to the control unit 6. The control unit 6 configures an IP packet from the supplied private section and extracts a necessary packet. The extracted packet is sent from the bidirectional line interface 5 to the personal computer groups 11 to 1n connected as terminal devices. In this case, the packet is transmitted according to the IP address.
[0018]
A procedure of the reception process in the embodiment configured as described above will be described. First, the operation of DTCP will be described.
[0019]
(1) The transmission apparatus transmits a DTCP HELLO packet at the same time as being activated. This packet includes information indicating the state on the transmission device side, and there are two states on the transmission device side: being broadcast or ending broadcast.
[0020]
(2) The DTCP HELLO packet is transmitted at a specific interval (referred to as HELLO INTERVAL, the recommended value is 10 seconds).
[0021]
(3) The receiving device side detects the state of the transmitting system by receiving the DTCP HELLO packet.
[0022]
(4) In normal conditions, (2) and (3) are repeated.
[0023]
(5) Even if the DTCP HELLO packet is not received within HELLO INTERVAL seconds, the receiving device waits for the next DTCP HELLO packet.
[0024]
(6) The standby state of (5) is maintained for HELLO LEAVE seconds (HELLO INTERVAL x 3 and the recommended value is 30 seconds).
[0025]
(7) If a DTCP HELLO packet cannot be received after waiting for HELLO LEAVE seconds, a timeout occurs and the receiving device closes the one-way line and switches the network to the ground line.
[0026]
In one embodiment of the present invention, after the timeout in (7) above, the one-way line interface 4 is diagnosed, and when it is determined that the one-way line interface 4 is unable to receive the DTCP HELLO packet, the interface is Is reactivated to restore normal communication. FIG. 2 is a flowchart of a processing procedure according to an embodiment.
[0027]
First, in step S1, a DTCP HELLO packet is received. When the DTCP HELLO packet is received, the process proceeds to step S2 and step S3, and the control unit 6 performs the main routine process. In parallel with this processing, the control unit 6 performs DTCP HELLO packet monitoring processing from step S4 to step S8.
[0028]
That is, the timeout count value is initialized to 0 (step S4), and then the application starts a subtraction timer for HELLO INTERVAL (seconds) as a background process (step S5). In step S6, it is determined whether the next DTCP HELLO packet has been received before the timeout. If the next DTCP HELLO packet is received before the timeout, the process returns to step S4. As long as the next DTCP HELLO packet is received before the time-out, the processes in steps S4 to S6 are repeated.
[0029]
If it is determined in step S6 that the next DTCP HELLO packet cannot be received before the timeout, the process proceeds to step S7, and the timeout count is incremented. In step S8, it is determined whether or not the timeout count value is greater than 3. In the case of 3 or less, the process returns to step S5, and the processes of steps S5 to S8 are repeated. When the processing from step S5 to step S8 is repeated three times and the timeout count value becomes 3 or more, the one-way line interface 4 is reset (initialization of the interface) in step S9.
[0030]
When initialization is completed, the parameters of the one-way line interface 4 are set in step S10. Reactivation is successful when the processing of step S9 and step S10 is completed.
[0031]
【The invention's effect】
Therefore, according to the present invention, even if the interface is hung up, it can be automatically reactivated, and the normal reception state can be quickly and reliably restored. Thereby, the reliability of the receiving apparatus can be improved, and the time during which the network is down due to a communication failure caused by the receiver can be significantly reduced. Furthermore, since the function according to the present invention is installed as background software, the user does not need to be aware of the existence of this function, so that maintenance is easy.
[Brief description of the drawings]
FIG. 1 is a block diagram showing an overall configuration of an embodiment of the present invention.
FIG. 2 is a flowchart used for explaining the operation of the embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Reception antenna, 2 ... Receiver, 3 ... Front end part, 4 ... One-way line interface, 5 ... Two-way line interface, 6 ... Control part, 7 ...・ Display unit, 11-1n ... Personal computer

Claims (4)

A front-end unit that selects and demodulates a desired signal from signals received by an antenna, and performs descrambling;
An interface for separating packets from the transport stream from the front end unit ;
A display unit for displaying whether or not the reception state is normal;
A control unit to which packets separated by the interface are supplied ;
The control unit detects a hang-up of the interface by detecting a plurality of times that a periodically transmitted packet is not supplied from the interface,
The control unit, the interface - in the case of detecting the hang of the face, the interface - the face initialized, receiving apparatus to reconfigure parameters. In claim 1,
A receiving apparatus comprising: software for detecting hang-up of the interface, initializing the interface , and resetting parameters as background software. A front-end unit that performs demodulation by selecting a desired signal from signals received by an antenna and performs descrambling, and an interface for separating packets from the transport stream from the front-end unit, and normal In a receiving method in a receiving apparatus comprising: a display unit that displays whether or not a reception state is present; and a control unit to which a packet separated by the interface is supplied.
Receiving a packet periodically transmitted by the antenna and the front end unit, and supplying the received packet to the control unit;
Detecting the hangup of the interface by detecting a plurality of times by the control unit that the packet is not supplied from the interface ;
The inter - when detecting a hang-up of the face, by the control unit, the interface - the face initialized, receiving method and a step to reconfigure parameters. In claim 3 ,
A reception method in which software processing for detecting hang-up of the interface, initializing the interface , and resetting parameters is executed in the background.

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