JPH0795497A - Power supply method/device - Google Patents

Abstract

PURPOSE:To attain the continuous input of output signals through a terminal equipment even when the supply of power is stopped from an external equipment by monitoring the output signal of the terminal equipment and starting the supply of power to the terminal equipment in place of the external equipment that has stopped the supply of power. CONSTITUTION:When a power switch is turned on by a user, a control circuit 8 outputs the channel selection data to a high frequency processing circuit 7 while the supply of power is disconnected to a down comparator 3. Then the circuit 8 monitors the output data of an A/D converter 17 and decides whether a satellite broadcast channel is received by some reception frequency. When the output data of the converter 17 rise on value O, the circuit 8 decides that some channel has been received. Thus the circuit 8 selects a desired channel in response to the channel selecting operation of the user without starting a power circuit 18.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a power supply method and a power supply device for various devices such as a satellite broadcast receiver which can share one antenna with a plurality of receiving systems.

[0002]

2. Description of the Related Art Conventionally, in this type of satellite broadcast receiving system, a down converter installed directly under an antenna is used to down-convert the frequency of a received signal, and thereby a satellite provided indoors using a coaxial cable. The antenna output is guided to the broadcast receiving device. At this time, the satellite broadcast receiving apparatus supplies power to the down converter via the antenna output coaxial cable, whereby the antenna can be installed by a simple wiring operation.

[0003]

By the way, in this type of satellite broadcast receiving system, by distributing the output signal of one down converter to each home and outputting it,
There is one in which this single down converter can be shared by a plurality of households.

When connecting a satellite broadcast receiving apparatus to such a co-listening system, when a coaxial cable is supplied with power as in a normal receiving system in a satellite broadcast receiving apparatus of each home, a plurality of down converters are provided. Power will be simultaneously supplied from the satellite broadcast receiving device.
In this case, in the co-listening system, the down converter connected to the coaxial cable may be damaged, and in extreme cases, an accident such as smoking may occur. Therefore, in this case, in the satellite broadcast receiving device of each home, it is necessary to control the stop of the power supply to the coaxial cable as necessary so that the power is not simultaneously supplied from the plurality of satellite broadcast receiving devices. .

In this case, for example, in the satellite broadcasting receiver, at the start of reception, the processing of the search tuning of all channels of the satellite broadcasting is executed with the power supply to the down converter not started, and the processing result of the search tuning. A converter power supply automatic control method for determining the necessity of power supply to the down converter based on the above is conceivable. In other words, in the process of this search channel selection, if any of the channels of all satellite broadcast channels can be received, it means that the down converter has already been supplied with power and the down converter is operating normally. The device can receive a desired satellite broadcast channel in response to a user's tuning operation without newly starting the supply of power. That is, the search and channel selection of all channels of the satellite broadcasting is performed with the power source for the converter of the satellite broadcasting receiving apparatus used for viewing and listening being turned off. When it is determined that there is broadcasting on one or more channels as a result of search channel selection, it is determined that the converter power supply is unnecessary and the converter power supply remains off.

On the other hand, when none of the channels of all satellite broadcasting channels can be received, the downconverter is supplied with power because the downconverted received signal is not input to the satellite broadcasting receiving device. In some cases, it may not exist. In this case, in the satellite broadcast receiving device, subsequently, the supply of power to the down converter is started, and the process of the second search channel selection is executed again.

When any channel can be received in this second search channel selection process, the down converter has started operating due to the start of power supply, and the satellite broadcast receiving device is switched to the down converter. Power can be supplied to receive a desired satellite broadcast channel in response to a user's channel selection operation. In this way, when it is determined that there is no broadcasting on all satellite broadcasting channels, the converter power supply is turned on, and all satellite broadcasting channels are searched and selected in that state. When it is determined that there is broadcasting on one or more channels, it is determined that the converter power supply is necessary, and the converter power supply is kept on.

On the other hand, in the case where neither channel can be received in the second search channel selection process, in this case, the down converter may not be connected to the satellite broadcast receiving device, and so on. In the device, the output of the power supply to the down converter is stopped to wait for the user's operation. That is, when it is determined that there is no broadcast on all satellite broadcast channels, it is determined that the satellite broadcast antenna is not connected, and the converter power supply is turned off. Thus, the satellite broadcast receiving device can supply power to the down converter only when power is not supplied from another satellite broadcast receiving device in the co-listening system.

However, in such a co-listening system, the user may turn off the power of a certain satellite broadcast receiving apparatus that has been supplying power to the down converter. In this case, the power to the down converter is turned off. Supply will be suddenly stopped. In this case, another satellite broadcast receiving device that controls the supply of power based on the search channel selection result suddenly cannot view the satellite broadcast receiving channel that was being viewed until then.

As described above, in the satellite broadcast receiving apparatus that supplies power to the down converter based on the search channel selection result at the start of reception, in order to continuously watch the program that has been watched up to that point, it is necessary to restart. There is a problem in that it is necessary to select the search channel to determine the necessity of power supply, and eventually the user needs to turn on the power switch and restart the power supply.

The present invention has been made in view of the above problems, and even when the power supply from another external device such as a satellite broadcast receiver is stopped, the output is continuously output from a terminal device such as a down converter. An object of the present invention is to provide a power supply method and a power supply device capable of inputting a signal.

[0012]

According to the present invention, there is provided the above object for a terminal device which operates with a power source supplied from an external device and outputs a predetermined output signal to a plurality of external devices. In an external device, the presence or absence of power supply to the terminal device is detected by monitoring the output signal, and when the power supply to the terminal device is stopped, the external power supply is stopped. This is achieved by a power supply method that starts supplying power to the terminal device instead of the device.

Further, according to the present invention, the above-mentioned object is achieved by monitoring the above-mentioned output signal with respect to a terminal device which operates with a supplied power source and outputs a predetermined output signal to a plurality of power supply devices. When the presence or absence of power supply to the terminal device is detected and the power supply to the terminal device is stopped, power is supplied to the terminal device instead of stopping the power supply. Is achieved by a power supply device that starts the. In the present invention, preferably, the terminal device is a down converter that down-converts and outputs an antenna input signal, and the power supply device is a satellite broadcast receiving device that demodulates and outputs the output signal. is there.

[0014]

According to the above structure, the power supply device such as the satellite broadcast receiving device detects the stop of the power supply to the terminal device when the power supply to the terminal device is stopped, and supplies the power instead. be able to.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below in detail with reference to the accompanying drawings. The examples described below are
Since it is a preferred specific example of the present invention, various technically preferable limitations are attached, but the scope of the present invention is, unless otherwise stated to limit the present invention, in the following description.
These aspects are not limited.

(1) Overall Configuration FIG. 1 is a block diagram showing an embodiment of a satellite broadcast receiving device as a power supply device according to the present invention. In FIG. 1, a satellite broadcast receiving system 1 has a down converter 3 arranged near the focal point of a parabolic antenna 2, and a waveguide provided at the tip of the down converter 3 receives a satellite broadcast signal. The down converter 3 frequency-converts (down-converts) the satellite broadcast signal into a frequency of 1 [GHz] band, and then converts the frequency-converted signal (first intermediate frequency signal, first IF signal) into the coaxial cable 3a. It outputs to the distributor 4 via. Down converter 3 at this time
Operates with a DC power supply supplied from the power supply circuit 18 of FIG. 2 via the coaxial cable 3a, whereby the satellite broadcast receiving system 1 can receive satellite broadcast by a simple wiring work. .

The distributor 4 in FIG. 1 has the coaxial cable 3a.
The received signal input via the above is distributed, and the distributed received signal is output to the satellite broadcast receiving devices 5 and 6 via the coaxial cable 3a. As a result, the satellite broadcast receiving devices 5 and 6 can receive the satellite broadcast by supplying power from the satellite broadcast receiving device 5 or 6 to the coaxial cable 3a.

FIG. 2 shows a system of the satellite broadcast receivers 5 and 6. In FIG. 2, the high frequency processing circuit 7 outputs the output signal S of the down converter 3 via the coaxial cable 3a.
1 is received, and a desired channel is selected based on the tuning data output from the control circuit 8 having the microcomputer configuration. That is, the high-frequency processing circuit 7 of FIG. 2 selects a desired channel by performing synchronous detection by a tuning circuit having a PLL circuit configuration based on the received data, and outputs a second intermediate frequency signal as a result of the tuning. Amplify with a predetermined amplifier circuit. Further, the high frequency processing circuit 7 inputs the output signal of this amplifier circuit to the built-in FM demodulation circuit and outputs a channel detection signal (output signal) of the selected channel. As a result, the satellite broadcast receivers 5 and 6 can detect, through the high frequency processing circuit 7, the selected channel image signal and the PCM audio signal transmitted after being QPSK modulated.

The video signal processing circuit 9 is adapted to input the received channel video signal by selectively inputting the output signal of the high frequency processing circuit 7 through a predetermined low-pass filter. Video signal is L
Dispersal removal processing is performed through the PF and output. As a result, the satellite broadcast receiving devices 5 and 6 can output the output signal SV of the video signal processing circuit 9 to a monitor device (not shown) to view a desired satellite broadcast.

The first band pass filter (BP) shown in FIG.
F) 10 extracts a signal component having a center frequency of 5.73 [MHz] from the output signal of the high frequency processing circuit 7 to extract and output a PCM audio signal transmitted by being QPSK modulated. The QPSK demodulation circuit 11 demodulates the output signal of the band pass filter 10 to demodulate and output a PCM audio signal which is data of a predetermined bit stream. PCM decoder 12
Decodes this PCM audio signal and outputs a digital audio signal SA.

As a result, the satellite broadcast receiving devices 5 and 6
Outputs the digital audio signal S1 to an audio signal processing circuit (not shown), performs a filtering process using a digital filter in this audio signal processing circuit,
Digital-to-analog conversion processing is performed and output.
The PCM audio signal transmitted after being PSK modulated can be auditioned.

At this time, the PCM decoder 12 decodes the PCM audio signal in frame synchronization with the synchronization circuit 13 in the first stage. The PCM decoder 12
The synchronization circuit 13 extracts information (frame synchronization flag) indicating whether the 16-bit synchronization data is synchronized. As a result, for example, when this frame synchronization cannot be obtained (when the audio frame synchronization is lost), the frame synchronization flag F is raised (the fact that the frame synchronization flag becomes NSYC = 1 is used).
That is, by monitoring this frame synchronization flag, it is possible to determine whether the input signal is a BS (compliant) standard signal or another signal.

When the frame synchronization cannot be obtained, the case where the synchronization is simply lost and the PCM of the satellite broadcasting system of this type
This corresponds to the case where the audio signal is not input, and in any case, it can be determined that the satellite broadcast cannot be correctly received. As a result, in this embodiment, the satellite broadcasting receivers 5 and 6 judge the necessity of power supply by the control circuit 8 based on the frame synchronization flag F.

On the other hand, the other band-pass filter 14 shown in FIG. 2 has a center frequency selected to be 11.5 [MHz] and receives the output signal of the high-frequency processing circuit 7. This band pass filter 14
The noise component of 8.5 [MHz] to 13 [MHz] (noise component of the demodulation band) is extracted from the output signal (detection signal) of the high-frequency processing circuit 7 by passing through the signal. That is, in this type of satellite broadcast receiving devices 5 and 6, the voltage corresponding to the magnitude of the noise level is read, and the noise level of the noise component included in the detection result is detected by the high frequency processing circuit 7 of the satellite broadcast receiving devices 5 and 6. It can represent the level of the input antenna input (DC output). Since the level of the antenna input indicates the approximate C / N of the received signal, it is possible to determine the presence or absence of broadcasting by providing a certain threshold level and determining whether the level is above or below that level.

As a result, when the noise level is high, it means that the antenna input having a high signal level is input to the high frequency processing circuit 7. In this case, power is supplied to the down converter 3 and the down converter 3 operates properly. You can judge that you are doing. On the contrary, when the noise level is small, it means that the antenna input having a small signal level is input to the high frequency processing circuit 7, and in this case, it can be determined that the down converter 3 is not operating properly.

As described above, if the satellite broadcast receiving devices 5 and 6 are provided with a predetermined threshold level and it is judged whether the noise level is above or below the threshold level, the satellite broadcast receiving devices 5 and 6 can be easily operated. It is possible to easily determine whether or not the input received signal is broadcast, and thus it is possible to determine whether or not the down converter 3 is operating correctly.

According to this criterion, the satellite broadcast receivers 5 and 6 input the output signal of the band pass filter 14 to the peak detection circuit 15 and detect the noise level by performing peak detection by the peak detection circuit 15. The amplifying circuit 16 is formed by, for example, a non-linear amplifying circuit whose gain rapidly changes at a predetermined input level, and amplifies and outputs the output signal of the peak detection circuit 15,
This input level is set as a threshold and the peak detection circuit 1
The noise level detected in 5 is amplified and output.

Analog digital conversion circuit (A / D) 1
7 is an output signal (antenna level,
The DC component) is A / D converted into a digital value of 6 bits and output. From the above, in this embodiment, the control circuit 8 uses the output data of the analog digital conversion circuit 17 as a reference, and further the frame synchronization flag F on the side of the synchronization circuit 13 as a reference. The processing and the automatic power supply processing procedure shown in FIG. 3 are executed. According to this procedure, the control circuit 8 causes the power supply circuit 18 to operate as necessary.
To supply power to the down converter 3.

That is, when the user turns on the power switch, the control circuit 8 sequentially outputs tuning data to the high frequency processing circuit 7 with the power supply to the down converter 3 stopped, thereby sequentially searching the satellite broadcasting channels. To do. At this time, the control circuit 8 monitors the output data of the analog digital conversion circuit 17, and thereby judges whether or not the satellite broadcasting channel can be received at any of the reception frequencies. Here, when the output data of the analog digital conversion circuit 17 rises from the value 0 (not all 0), it is determined that any channel has been received (there is broadcasting), and the control circuit 8 determines that the power supply circuit has been received. The desired channel is selected in response to the user's channel selection operation without starting 18.

That is, in this case, since power is supplied from the satellite broadcast receiving device 5 or 6 connected to the down converter 3, the satellite broadcast receiving device 6 or 5 outputs the power to the down converter 3. The desired channel can be received without starting the power supply. On the other hand, when the output data of the analog digital conversion circuit 17 is held at the value 0 (all 0s), the signal level at the antenna input is extremely low in this case, so that power is supplied to the down converter 3. It is possible that it has not been done.

As a result, the control circuit 8 activates the power supply circuit 18 in this case to start the supply of power to the down converter 3, and then outputs the tuning data again to perform the search tuning process. Run. Here, when the output data of the analog digital conversion circuit 17 rises from the value 0, the control circuit 8 determines that one of the channels has been received, and continues to supply power to the down converter 3, thereby A desired channel is selected in response to a user's channel selection operation.

On the other hand, even in this search channel selection,
The output data of the analog digital conversion circuit 17 may be held at 0, the down converter 3 may not be connected, and the down converter 3 may be out of order. In these cases, the control circuit 8
Stops the operation of the power supply circuit 18 and down converter 3
The power supply to the power supply is stopped to effectively prevent the occurrence of unexpected errors.

When the satellite broadcast receiving apparatus starts receiving satellite broadcasts in this way, the control circuit 8 subsequently executes the processing procedure shown in FIG. 3 at a predetermined cycle, for example. In this process, as described above, the antenna level indicates the approximate C / N of the received signal. Therefore, by setting a certain threshold level and discriminating whether the level is above or below that level, the presence / absence of broadcasting is determined. To judge. Also, the antenna level (DC output) is A / D converted with 6 bits, and it is determined that there is no broadcast when the antenna level is 0 (all 0), and there is broadcast otherwise. Also, by utilizing the fact that the frame synchronization flag (NSYC = 1) is set when the audio frame synchronization is lost, the BS (compliant) standard signal is absent when NSYC = 1 and the BS (compliant) standard signal is present when NSYC = 0. It also makes a judgment.

The control circuit 8 moves from step SP1 to step SP2, where the analog digital conversion circuit 1
Based on the value of the output data of 7, it is determined whether the antenna input level is 0 level. In step SP2, when the antenna levels are all 0, it is determined that there is no broadcast. When the frame synchronization flag NSYNC = 1, it is determined that the audio frame synchronization is out of sync. When a negative result is obtained for the antenna level in step SP2, the control circuit 8 subsequently determines whether or not the frame synchronization flag F has risen, and when a negative result is obtained here as well, in this case the satellite direction is normal. Since this has been received, the process proceeds to step SP3 to end this processing procedure.

On the other hand, when the antenna input level is 0 level (all 0) or when the frame synchronization flag F is raised (NSYNC = 1), the control circuit 8
Moves to step SP4, determines that the satellite broadcast that has been received up to that point can no longer be received (determines that the broadcast has changed from being present to not being present), and then proceeds to step SP5. It should be noted that this processing is executed by applying an interrupt method by monitoring the output data of the analog digital conversion circuit 17 and the frame synchronization flag F in the control device 8. In this case, in the satellite broadcast receiving devices 5 and 6, it is considered that the down converter 3 stops operating due to the stop of the power supply to the down converter 3, so that the built-in power supply circuit 18 shifts to the down converter 3. Determine if power is already being supplied.

When a positive result is obtained in step SP5 (converter power supply is turned on), the down converter 3 is used in this case.
Since the control circuit 8 is considered to be operating normally, the control circuit 8 proceeds to the next step SP6, determines that the reception condition has deteriorated, preferably displays a predetermined message, and then proceeds to step SP3. On the other hand, step S
If a negative result is obtained in P5, in this case, it is considered that another satellite broadcast receiving device 6 or 5 that has been supplying power to the down converter 3 up to then stops the supply of power. At this point, the operation of the power supply circuit 18 is started (converter power supply is turned on), and the supply of power to the down converter 3 is started.

Subsequently, the control circuit 8 moves to step SP8. Step SP8 is the same as step SP2.
In step SP8, it is determined again based on the output data of the analog digital conversion circuit 17 whether the antenna input level is 0 level (all 0). If a negative result is obtained here, the frame synchronization flag F is subsequently determined. To determine whether is up. When a negative result is obtained in step SP8, the control circuit 8 starts the supply of power to the down converter 3 in this case and normally starts the reception, and thus proceeds to step SP9 to distribute the down converter 3. It is determined that the satellite broadcasting cannot be received because the other shared satellite broadcasting receiving device 6 or 5 has stopped the supply of power to the down converter 3 (step SP9), and the down converting 3 The power supply is continued and the process proceeds to step SP3.

In this way, the satellite broadcast receivers 5 and 6 detect the noise level at a predetermined cycle to monitor the antenna input, and judge whether or not the satellite broadcast can be correctly received based on the monitor result. It is supposed to do. If it cannot be received correctly, down converter 3
It is possible to automatically start the power supply to the satellite and continue to receive the satellite broadcast that has been received until then. Therefore, in the satellite broadcast receiving devices 5 and 6, the power can be supplied to the down converter 3 as necessary by selecting the search channel at the time of starting the reception, so that the power source provided in the conventional satellite broadcast receiving devices can be supplied. The supply switching switch can be omitted, and the entire configuration can be simplified accordingly.

The same installation work can be performed regardless of whether it is connected to the co-listening system or a dedicated antenna, and the installation can be as simple as when receiving terrestrial television broadcasting.

On the other hand, when an affirmative result is obtained at step SP8, the control circuit 8 proceeds to step SP1.
0, in this case, even if the power supply to the down converter 3 is started, satellite broadcasting cannot be received correctly,
A predetermined message is displayed when it is determined that the reception status has deteriorated. Then, the control circuit 8 moves to step SP11,
At this point, the supply of power to the down converter 3 is stopped and the process proceeds to step SP3 to complete this processing procedure.

According to the above configuration, for example, when the satellite broadcast receiving device 5 of FIG. 1 first tries to receive a satellite broadcast, the satellite broadcast receiving device 5 supplies the down converter with the power supply for the converter. If you do not do this, you will not be able to receive satellite broadcasts. Therefore, the satellite broadcast receiving device 5 supplies power for the down converter to view the satellite broadcast. In this state, when it is desired to receive the satellite broadcast by the other satellite broadcast receiving device 6, the satellite broadcast receiving device 5 has already supplied power for the down converter 3, so Satellite broadcasting can be viewed without supplying power for the converter.

However, if the satellite broadcast receiving apparatus 5 is turned off in this state, the satellite broadcast receiving apparatus 5 does not supply power for the down converter. Therefore,
The other satellite broadcast receiving device 6 suddenly loses sight of the satellite broadcast. Therefore, in the embodiment of the present invention, for example, another satellite broadcast receiving device 6 detects the presence or absence of satellite broadcast, and the down converter 3 is automatically provided from the satellite broadcast receiving device 6 side based on the detection result. By supplying power to the satellite broadcast receiving device 5, the satellite broadcast receiving device 5 can continuously watch the satellite broadcast regardless of the state of the satellite broadcast receiving device 5. That is, after the start of reception, by monitoring the signal level of the antenna input output from the down converter 3 in a predetermined cycle, the power supply to the down converter 3 can be started as needed, and as a result, one satellite broadcast receiving device is provided. Even if the power supply from 5 stops, another satellite broadcast receiver 6
Can continuously drive the down converter 3 to receive satellite broadcasting.

The present invention is not limited to the above embodiment. For example, in the above-described embodiment, the case where the noise level is detected to determine the presence / absence of the antenna input has been described, but the present invention is not limited to this, and the signal level of the antenna input may be directly monitored as necessary. May be. Further, the present invention can be applied not only to the satellite broadcast receiving system but also to devices in other fields.

[0044]

As described above, according to the present invention, the presence or absence of power supply to the terminal device is detected by monitoring the output signal of the terminal device, and when the power supply to the terminal device is stopped. , By starting the supply of power to the terminal device in place of the external device that has stopped the supply of power, power can be supplied to the terminal device when necessary, and power can be supplied from other external devices. Even when stopped, the output signal can be continuously input from the terminal device.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a satellite broadcast receiving system including a satellite broadcast receiving device as a power supply device of the present invention.

FIG. 2 is a block diagram showing the satellite broadcast receiving device.

FIG. 3 is a flowchart for explaining the operation.

[Explanation of symbols]

 1 Satellite Broadcasting Reception System 2 Antenna 3 Down Converter 3a Coaxial Cable 5 and 6 Satellite Broadcasting Receiver 8 Control Circuit 18 Power Supply Circuit

Claims (3)

[Claims] 1. A terminal device, which operates with a power supply supplied from an external device and outputs a predetermined output signal to a plurality of external devices, wherein the external device monitors the output signal to provide the terminal. Detects the supply of power to the device,
A power supply method, wherein when power supply to the terminal device is stopped, power supply to the terminal device is started instead of the external device that has stopped the power supply. 2. A power supply to a terminal device, which operates with a supplied power and outputs a predetermined output signal to a plurality of power supply devices, by monitoring the output signal. When the presence or absence is detected and the power supply to the terminal device is stopped, the power supply is started to the terminal device instead of stopping the power supply. apparatus. 3. The terminal device is a down converter that down-converts and outputs an antenna input signal, and the power supply device is a satellite broadcast receiving device that demodulates and outputs the output signal. The power supply device according to claim 2.