JPH11355749A - Digital broadcast receiver and method for saving power consumption in the digital broadcast receiver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a digital broadcast receiver that saves power consumption. SOLUTION: The digital broadcast receiver is provided with a means that turns off a power supply for a circuit required to acquire qualification provision data when a power supply OFF command is received and that starts counting a consecutive power OFF time, a means that continues counting of the consecutive power OFF time in the case that the consecutive power ON time is shorter than a 1st prescribed time Tx even when a power ON command is received before the consecutive power OFF time reaches a 2nd prescribed time (T-Tx) shorter than a transmission period T of the qualification provision data by the 1st prescribed time Tx which is longer than a re-transmission period Ta of the qualification provision data, and a means that turns on the power supply of the circuit required for acquiring the qualification provision data for the 1st prescribed time Tx when the consecutive power OFF time reaches the 2nd prescribed time (T-Tx).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a digital broadcast receiver and a method for reducing power consumption in the digital broadcast receiver.

[0002]

2. Description of the Related Art In CS broadcasting, entitlement data for each user (for example, individual information (EMM)) is transmitted. The qualification grant data includes data (contract information) indicating a channel (program) that can be viewed by the user specified by the contract, key data for descrambling the user, and the like. Sent with Since the personal information is used to determine whether or not the program can be viewed by the user, to cancel the scramble, etc., the CS digital broadcast receiver can be licensed even when the power is off. You need to be able to get data.

For this reason, in the conventional CS digital broadcast receiver, it is necessary to supply power to a circuit for acquiring qualification data even when the power is off.
There is a problem that power consumption increases.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a digital broadcast receiver and a method for reducing power consumption in a digital broadcast receiver, which can reduce power consumption.

[0005]

A digital broadcast receiver according to the present invention is a digital broadcast receiver in which entitlement data for each user is repeatedly transmitted over a predetermined retransmission period Ta and a predetermined transmission period T. A first means for turning off the power of the circuits necessary for acquiring the qualification data and starting timing of the duration of the power-off when the power-off command is input, resending the qualification data A second predetermined time (T) shorter than the transmission period T of the entitlement data by a first predetermined time Tx longer than the cycle Ta.
-Tx), a power-on command is input before the power-off duration reaches, and the power-on duration is set to the first time.
A second means for terminating the measurement of the power-off duration by the first means when the predetermined time Tx has been reached, and a power-on command before the power-off duration reaches the second predetermined time (T-Tx). If the power-on continuation time is shorter than the first predetermined time Tx even when the power-on continuation time is input, a third means for continuing the measurement of the power-off continuation time by the first means
The power-off duration is the second predetermined time (T-
When (Tx) has been reached, a fourth means is provided for turning on a power supply of a circuit necessary for acquiring the entitlement data for the first predetermined time Tx.

The power consumption saving method for a digital broadcast receiver according to the present invention is characterized in that the entitlement data for each user is repeatedly transmitted over a predetermined retransmission period Ta and a predetermined transmission period T in the digital broadcast receiver. In the power saving method, when a power-off command is input, a first step of turning off a power supply of a circuit necessary for acquiring qualification data and starting timing of a power-off duration time, A second predetermined time (T-Tx) shorter than the transmission period T of the entitlement data by a first predetermined time Tx longer than the retransmission cycle Ta of the entitlement data
If the power-on command is input before the power-off duration reaches and the power-on duration reaches the first predetermined time Tx, the first means stops measuring the power-off duration. In the second step, before the power-off duration reaches the second predetermined time (T-Tx), if the power-on duration is shorter than the first predetermined time Tx even if a power-on command is input. A third step of continuing to measure the power-off duration by the first means, and the power-off duration by the second predetermined time (T-T).
and x) when a power supply of a circuit necessary to acquire the qualification data is turned on for the first predetermined time Tx, and then the process proceeds to the first step. It is characterized by.

[0007] The information on the retransmission cycle Ta and the transmission period T may be set in the digital receiver in advance, or may be transmitted to the digital receiver by broadcasting.

[0008]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows the configuration of a television receiver having a built-in CS digital broadcast receiver.

The CS digital receiving unit includes a tuner unit 1, a descrambler 2, an MPEG-Transport Stream (TS) packet separator 3, an MP
EGAV decoder (MPEG Audio Video Decoder) 4, OSD (On Screen Displa) which is a hardware for graphics
y) The circuit 5 and the like are provided. Each of these parts is the main CP
Controlled by U10.

The main CPU 10 performs system management operations such as control and monitoring of all components in the system and interrupt processing in accordance with a program stored in the ROM 11.

The tuner unit 1 includes a tuning unit, an IQ detector, a QPSK demodulator, and an error corrector. After selecting a desired wave and converting an input signal to baseband, the tuner unit 1 performs demodulation and error correction processing. Output a packet.

When a pay broadcast is received, the descrambler 2 descrambles the TS packet of the corresponding program using the descramble key. The descramble key is IC
The data is output from the main CPU 10 with reference to the qualification data stored in the card 13.

The TS packet contains video, audio information and service information (SI: Service Information) of a plurality of programs. The service information includes program information for a program guide, qualification data, and the like. The MPEG-TS packet separator 3 receives the T
Separates only S packets and converts video and audio packets to MPE
Outputs the G packet to the GAV decoder 4 and stores the SI packet in the RAM 12
To load. Video and audio packets are MPEGAV
The video data is restored to the NTSC encoder 7 and the audio data is restored to the audio DAC (DA Converte
r) Output to 8.

After performing predetermined processing on the input video data, the NTSC encoder 7 outputs a Y / C separated analog video signal to a main circuit of the television. The audio signal output from the audio DAC 8 is also output to the main circuit of the television.

The main CPU 10 extracts necessary information from the SI packet loaded into the RAM 12, creates screen data such as a program guide, and displays a user interface screen via the OSD circuit 5. Further, the main CPU 10 causes the IC card 13 to store the qualification data loaded in the RAM 12.

The sub CPU 20 is connected to the main CPU 10 and T
In addition to handling communication with a channel selection CPU (not shown) in the V circuit, controlling the tuner unit 1 and the NTSC encoder 7, and controlling the power supply control circuit 23 for controlling power supply to each component. . The sub CPU 20
A timer 21 and a second timer 22 are provided.

The IC card 13 stores charging information and qualification data (including contract information and key data), and periodically uploads the information to the broadcasting company center via the modem 14. .

Conventionally, even when the power is off,
Power is supplied to the sub CPU 20, the main CPU 10, the tuner unit 1, the descrambler 2, and the MPEG-TS packet separator 3 in order to acquire the qualification data. The power is supplied only to the sub CPU 20 among these components.

However, if the power-off state continues for a predetermined time or more, a situation may occur in which entitlement data cannot be obtained. Therefore, when the power is turned off, the sub CPU 20 performs a power saving process described later and Tuner unit 1, descrambler 2, MPEG
-Supply power to the TS packet separator 3 and the main CPU 10.

Hereinafter, the power saving process performed by the sub CPU 20 when the power is turned off will be described.

As shown in FIG. 2, the entitlement data for a certain user is transmitted at a substantially constant cycle (hereinafter referred to as retransmission cycle) Ta immediately after the contract and for a predetermined period (hereinafter referred to as entitlement data transmission period) T. Sent repeatedly. When the content of the entitlement data is updated, it is similarly transmitted at a substantially constant cycle Ta for a predetermined period T. The cycle Ta is, for example, 10 to 20.
Minutes, and the period T is, for example, about 2 to 5 days.

When the entitlement data is updated, as shown in FIG. 3, period T1 (the same length as period T)
In this case, the entitlement data for a certain user is
In the next period T2 (the same length as the period T), the updated entitlement data for the user is updated in the retransmission cycle Ta.
Sometimes sent by.

If the power of the television receiver is turned on for a period longer than the retransmission period T1 during the qualification data transmission period T, the qualification data can always be obtained. Conversely, if the power of the television receiver is not turned on for a period longer than the retransmission period Ta during the qualification data transmission period T, the qualification data may not be obtained.

Therefore, in the case where the power of the television receiver is not turned on for a time longer than the retransmission cycle Ta during the qualification data transmission period T, a predetermined time Tx longer than the retransmission cycle Ta in the qualification data transmission period T Only the circuits necessary for acquiring the qualification data (tuner unit 1, descrambler 2, MPEG-
If power is supplied to the TS packet separator 3 and the main CPU 10), the qualification data transmitted during the qualification data transmission period T can be obtained.

In the power saving process performed by the sub CPU 20 when the power is turned off, when the entitlement data transmitted during the entitlement data transmission period T when the power is turned on is not acquired, that is, when the power of the television receiver is turned off. Immediately after the power is turned off, the duration of the power-off is monitored on the assumption that the qualification data transmission period T starts.
Then, as shown in FIG. 2, when the power-off duration reaches a time (T-Tx) shorter than the period T by a predetermined time Tx longer than the retransmission cycle Ta, the entitlement data is transmitted for a predetermined time Tx. Supply power to the circuits needed to obtain However, even if the power of the television receiver is turned on during the monitoring of the power-off duration, if the power-on time is shorter than the predetermined time Tx, the monitoring of the power-off duration is continued.

The information about the retransmission cycle Ta and the transmission period T may be set in the receiver in advance, or may be transmitted by broadcasting. When the retransmission period Ta and the transmission period T are transmitted by broadcasting, it is preferable to transmit the retransmission period Ta and the transmission period T periodically as general information. In the case where the retransmission period Ta and the transmission period T are transmitted by broadcasting, the receiver receives the information on the retransmission period Ta and the transmission period T, and stores the information in an IC card or other storage device.

FIG. 4 shows a procedure for power saving processing performed by the sub CPU 20 when the power is turned off.

When the power of the television receiver is turned off in response to the power-off command, the power of each unit other than the sub CPU 20 is turned off, and the measurement of the power-off duration T-OFF is started based on the first timer 21. (Step 1). Here, the power-off duration T-OFF includes a power-on time shorter than Tx after the power-off.

Then, it is monitored whether or not a power-on command has been input (step 2) and whether or not the power-off duration T-OFF has reached (T-Tx) (step 3).

The power-off duration T-OFF is (TT-
If the power-on command is input before reaching x), all the powers are turned on (step 5) and the second power is turned on.
Time measurement of the power-on duration T-ON is started based on the timer 22 (step 6).

Then, the power-on duration T-ON is T
It is monitored whether x has been reached (step 7) and whether a power-off command has been input (step 8). If the power-on duration T-ON has reached Tx (YES in step 7), the current power saving processing ends.

If a power-off command is input before the power-on duration T-ON reaches Tx (NO in step 7 and YES in step 8), power is turned off except for the sub CPU 20 ( Step 9) and return to step 2.

The power-off duration T-OFF is (T-T
x) (YES in Step 3), the circuits (the tuner unit 1, the descrambler 2, the MPEG-TS packet separator 3, and the main CPU 10) required to acquire the qualification data are sent for a predetermined time Tx. During this period, power is supplied (step 4). Thereafter, there is a possibility that new entitlement data will be sent in the next entitlement data transmission period T, so the process returns to step 1 and the same processing as described above is started.

According to the above embodiment, even when the power-off state of the television receiver continues, the circuit required to acquire the entitlement data only for the minimum time required to acquire the entitlement data Is turned on. Therefore, the power consumption can be greatly reduced as compared with the conventional example in which the power supply of the circuit necessary for acquiring the qualification data is always turned on when the power of the television receiver is turned off.

[0036]

According to the present invention, power consumption can be reduced.

[Brief description of the drawings]

FIG. 1 is a block diagram illustrating a configuration of a television receiver with a built-in CS digital broadcast receiver.

FIG. 2 is a schematic diagram showing a retransmission cycle Ta and a transmission period T of entitlement data.

FIG. 3 is a schematic diagram showing an example in which different entitlement data is sent in a period T1 and a next period T2.

FIG. 4 is a flowchart showing a procedure of a power saving process performed by a sub CPU 20 when the power is turned off.

[Explanation of symbols]

 Reference Signs List 1 Tuner unit 2 Descrambler 3 MPEG-TS packet separator 4 MPEG AV decoder 5 OSD circuit 10 Main CPU 11 ROM 12 RAM 13 IC card 20 Sub CPU

Claims (4)

[Claims] 1. A digital broadcast receiver in which qualification data for each user is repeatedly transmitted over a predetermined transmission period T at a predetermined retransmission cycle Ta. First means for turning off the power of the circuit necessary to obtain the qualification data and starting to measure the duration of the power-off time. The qualification is performed for a first predetermined time Tx longer than the retransmission cycle Ta of the qualification data. Before a power-off duration reaches a second predetermined time (T-Tx) shorter than the data transmission period T, a power-on command is input and the power-on duration reaches the first predetermined time Tx. In some cases, the second means for terminating the measurement of the power-off duration by the first means, and the power-on command is issued before the power-off duration reaches the second predetermined time (T-Tx). If the power-on continuation time is shorter than the first predetermined time Tx even if it is input, the third means for continuing the measurement of the power-off continuation time by the first means, and the power-off continuation time is the second When the predetermined time (T-Tx) has been reached, the power supply of the circuit necessary for acquiring the qualification data is switched to the first predetermined time Tx.
A fourth means for turning on during the period. 2. The retransmission cycle Ta and the transmission period T
The digital broadcast receiver according to claim 1, wherein the information about the digital broadcast is transmitted by broadcasting. 3. A method for reducing power consumption in a digital broadcast receiver in which qualification data for each user is repeatedly transmitted over a predetermined transmission period T at a predetermined retransmission cycle Ta, wherein a power-off command is input. Sometimes, the first step of turning off the power of the circuit necessary to acquire the qualification data and starting to count the duration of the power-off is also performed. The first step is longer than the retransmission cycle Ta of the qualification data. Before a power-off duration reaches a second predetermined time (T-Tx) shorter than the qualification data transmission period T by the time Tx, a power-on command is input and the power-on duration is set to the first power-on duration. When the predetermined time Tx has been reached, a second step of terminating the time measurement of the power-off duration by the first means, and the power-off duration is set to the second predetermined time (T- If the power-on continuation time is shorter than the first predetermined time Tx even if the power-on command is input before reaching Tx), the third step is to continue the time measurement of the power-off continuation time by the first means. And when the power-off duration reaches the second predetermined time (T-Tx), the power of the circuit necessary to acquire the qualification data is turned on for the first predetermined time Tx. 4. A method for reducing power consumption in a digital broadcast receiver, comprising: a fourth step of shifting to a first step thereafter. 4. The retransmission cycle Ta and the transmission period T
The method for reducing power consumption in a digital broadcast receiver according to claim 3, wherein the information about the digital broadcast receiver is transmitted by broadcasting.