JPH0438087A - Channel automatic setting device for catv receiver - Google Patents

Abstract

PURPOSE:To receive arbitrary CATV broadcast with one operation by a receiver by not only setting the receiver to a reception channel for CATV broadcast in accordance with giving of a channel select command but also giving a reception select signal to a hub so that CATV broadcast to which the select command is given is received by this reception channel. CONSTITUTION:A select signal decoding circuit 338 discriminates whether the channel select signal indicates the change of a CATV channel or not; and when it does not indicate the change of the CATV channel, that is, it indicates the change of a BS channel, a local oscillation signal corresponding to the BS channel is generated from a local oscillator 333. The select signal decoding circuit 338 gives the channel select signal to an I/O control circuit 340. This circuit 340 gives the channel select signal to an encoder 35 from an interface circuit 36 through a bus. This channel select signal is transmitted to a hub 2 from the encoder 35 through an E/O transducer 36, an optical synthesizer 31, and a subscriber system fiber 5.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic channel setting device for a CATV receiver, and in particular, it is a channel automatic setting device for a CATV receiver. selects and distributes television signals to each subscriber's BS tuner;
In an optical CATV system in which a channel selection signal from a BS tuner is transmitted from an encoder to a hub via a bus, a CATV reception system that allows the BS tuner to automatically set the receiving channel for optical CATV broadcasting using a channel selection remote control. This invention relates to an automatic channel setting device for a machine.

[Prior Art] In urban CATV including independent broadcasting and two-way transmission, there is a strong demand for multi-channel video signals and higher quality. Furthermore, recently, optical fibers, which have superior characteristics such as broadband, low loss, and non-dielectric properties, have been increasingly used as transmission media compared to coaxial cables.

As an example of CATV that uses optical fiber as a transmission medium, an FM multiplex high-definition optical CATV system using a demand access method (IEICE Research Report 0C3)
89-51, pages 7 to 12, 1989).

FIG. 3 is a schematic block diagram showing the overall configuration of the above-mentioned proposed optical CATV system. In FIG. 3, the optical CATV system is composed of an optical CATV head end 1, a hub 2, and a subscriber 3. The CATV headend 1 is installed at a CATV broadcasting station, where 34 channels of TV signals from cameras, VTRs, etc., which are the sources of MUSE signals, are converted to FM using an FM modulator at different carrier frequencies.
Modulated and multiplexed into electrical/optical (Elo) converter 12
The signal is converted into an optical signal and transmitted to the hub 2 via the trunk optical fiber cable 4.

The hub 2 is installed on a telephone pole etc. near multiple subscribers 3,
In response to a request from the subscriber 3, four channels of FM multiplexed signals from the 34 channels transmitted from the optical CATV head end 1 are distributed to each subscriber 3. That is, in the hub 2, the optical multiplexed signal transmitted from the trunk optical fiber cable 4 is given to the optical/electrical (0/E) converter 21, converted into an electrical signal, and then sent to the 4-channel selection circuit 2.
given to 2. The 4-channel selection circuit 22 selects 4-channel television signals from among the 34-channel television signals according to a control signal given from the local control circuit 23. The selected 4 channel TV signal is E10
The signal is converted into an optical signal by the converter 24, and transmitted to each subscriber 3 via the optical combiner 26 via the subscriber system optical fiber 5.

At the subscriber 3, the optical signal is converted into an electrical signal for each channel by the O/E converter 32 via the optical combiner 31, and the television signal of each channel is transmitted to the BS china 33.
received by. When the channel selection remote controller 34 gives a command to select any one of the BS channels, the BS tuner 33 gives a channel selection signal to the encoder 35 . The channel selection signals given from the four BS tuners 33 are multiplexed by the encoder 35, converted into optical signals by the E10 converter 36, and then sent to the optical combiner 31. Subscriber optical fiber cable 5. The signal is applied to the O/E converter 25 via the optical combiner 26, converted into an electrical signal, and then applied to the local control circuit 23. The local control circuit 23 provides the four-channel selection circuit 22 with a control signal corresponding to the channel selection signal.

The 4-channel selection circuit 22 selects a desired channel of television signal according to the control signal.

[Problems to be Solved by Invention E] By the way, in the optical CATV system shown in FIG.
Can be used with a tuner. In other words, the conventional B
By allocating, for example, the L channel of the S tuner to optical CATV broadcasting, it is possible to receive not only satellite broadcasting but also optical CATV broadcasting. The problem here is which of the satellite broadcasting channels should be assigned the optical CATV broadcasting channel. For example, if one channel of the BS tuner is allocated to optical CATV broadcasting, when a viewer wants to watch one of the 34 channels of optical CATV broadcasting from satellite broadcasting, he or she must first operate the channel selection remote control 34 and select one channel. After selecting a channel, it is necessary to select one of the 34 channels of optical CATV broadcasting, and the channel selection remote control 34 must be operated twice, which is cumbersome.

Therefore, the main object of the present invention is to simplify complicated operations by automatically setting the receiver to the channel for CATV broadcasting when a selection is made to watch one of multiple channels of CATV broadcasting. An object of the present invention is to provide an automatic channel setting device for a cATv receiver.

[Means for Solving the Problems] This invention provides a frequency multiplexed multi-channel CATV system.
Broadcast signals are transmitted from the head end to the hub, and the C of a minority of the multiple channels frequency-multiplexed from the hub.
In a CATV receiver that transmits an ATV broadcast signal to a subscriber and receives multiple channels of broadcast radio waves on one receiving channel of the receiver, the receiver receives any of multiple channels of CATV broadcast signals. a selection command means for giving a command to select one of the CATV broadcasts; and when the selection command means issues a selection command to one of the plurality of channels of broadcast radio waves, causing a receiver to receive the broadcast radio waves of that channel; In response to selection of one of the multiple channels of CATV broadcasting, setting the receiver to a certain reception channel, and
and a control means for supplying a reception selection signal to the hub so that the selected CATV broadcast is received on the reception channel.

[Function] The automatic channel setting device for a CATV receiver according to the present invention sets the receiver to CAT in response to a command to select one of a large number of CATV broadcast channels.
In addition to setting the reception channel for V broadcasting, a reception selection signal is also given to the hub so that the CATV broadcast that has been selected is received on that reception channel, so the receiver is automatically set to the CATV broadcasting channel. Selected CATV when set to , and CATV broadcasting of multiple channels
Can receive broadcasts.

[Embodiment of the Invention] FIG. 2 is a schematic block diagram of a BS tuner in an embodiment of the invention.

The BS tuner 33 includes an O/E converter 3 shown in FIG.
The RF multiplied signal is given from 2, and this RF multiplied signal tuning section 33
By the mixer 332 included in the local oscillator 333
The intermediate frequency signal is mixed with the local oscillation signal output from the oscillator, and an intermediate frequency signal is output. This intermediate frequency signal is applied to a demodulator 335 via a filter 334 and demodulated into a video signal.

In the example shown in FIG. 3, it is possible to select one of the three channels of television signals, but in this embodiment, any one channel of television signals can be selected from among the 40 channels of television signals. It is assumed that the signal can be selected. Selecting one channel of television signals from 40 channels of television signals is performed by a channel selection remote control 34 provided corresponding to the BS tuner 33.

The channel selection signal from the channel selection remote control 34 is received by the remote control reception circuit 336 and sent to the CPU 33.
7 is given. The CPU 337 is the selection signal decoding circuit 33
8, channel display control circuit 339 and I10 control circuit 34
Including 0. The selection signal decoding circuit 338 decodes the selection signal and provides it to the I10 control circuit 340 as well as to the channel display control circuit 339 to display the selected channel number on the display 341. Further, the channel selection signal is also given to the local oscillator 333, and a local oscillation signal corresponding to the selected channel number is given to the mixer 332.

An I10 interface circuit 36 is connected to the I10 control circuit 340. Interface circuit 36 includes a driver 37, a receiver 38, and resistors R1 to R4. The driver 37 outputs the channel selection signal output from the I10 control circuit 340 to the encoder 35. Receiver 38
provides the CPU 337 with a channel selection signal output from another BS tuner. CPU337 is Resino <38
When a channel selection signal is given from another BS tuner via the BS tuner, the driver 37 is placed in a temporary standby state, and output of the channel selection signal to the encoder 35 is prohibited, thereby controlling the channel selection signals so that they do not conflict with each other.

A resistor R1 is connected between the input side of the receiver 38 and the power supply, and a resistor R2,
R3 is connected in series, and a resistor R4 is connected between the input side and ground. These resistors R1 to R4 are used to bring the a-power of the driver 37 to the "L" level when the bus is at high impedance, and are selected to have negligible values when the bus is active.

FIG. 1 is a flowchart illustrating the specific operation of an embodiment of the present invention.

Next, with reference to FIG. 1 and FIG. 2, a specific operation of an embodiment of the present invention will be described.

When the channel selection remote control 34 shown in FIG. 2 is operated to issue a command to select a channel, a channel selection signal from the channel selection remote control 34 is received by the remote control reception circuit 336 and provided to the CPU 337. Selection signal decoding circuit 338 decodes the channel selection signal and provides a number representing the channel to channel display control circuit 339. Channel display control circuit 339 causes display 341 to display the number.

The selection signal decoding circuit 338 detects that the channel selection signal is CATV.
Determine whether the channel change is indicated and CA
When the TV channel is not changed, that is, when the BS channel is changed, the local oscillator 333 generates a local oscillation signal corresponding to the BS channel. If CAT
If the V channel is changed, the selection signal decoding circuit 338 causes the local oscillator 333 to oscillate a local oscillation signal corresponding to the CATV channel among the BS channels.

Additionally, selection signal decoding circuit 338 provides a channel selection signal to I10 control circuit 340. I10 control circuit 340
provides a channel selection signal from the interface circuit 36 to the encoder 35 via the bus. This channel selection signal is transmitted from encoder 35 to E10 as shown in FIG.
Converter 36. Photosynthesizer 31. It is transmitted to the hub 2 via the subscriber optical fiber 5.

In the hub 2, the channel selection signal transmitted from the subscriber optical fiber 5 is given to the local control circuit 23 via the optical combiner 26.0/E converter 25, and the local control circuit 23 applies the channel selection signal to the local control circuit 23. A control signal is given to the 4-channel selection circuit 22 to select the corresponding channel. In response, the 4-channel selection circuit 22 transmits the CATV broadcast signal of the selected channel to the BS tuner 33.

Therefore, by operating the channel selection signal remote control 34 once, the BS tuner 33 is automatically set to the CATV channel, and the 40-channel CA
Any TV broadcast can be selected.

[Effects of the Invention] As described above, according to the present invention, in response to a selection instruction for any one of multiple channels of CATV broadcasting being given by the selection instruction means, the receiver is
In addition to setting the receiving channel for broadcasting, a reception selection signal is given to the hub so that the CATV broadcast to which the selection command has been given is received on that reception channel.
A receiver can receive arbitrary CATV broadcasts from multiple channels with a single operation.

[Brief explanation of the drawing]

FIG. 1 is a flow diagram for explaining the operation of an embodiment of the present invention. FIG. 2 shows B in one embodiment of this invention.
FIG. 2 is a schematic block diagram of an S tuner. FIG. 3 is a schematic block diagram showing the overall configuration of an optical CATV system to which the present invention is applied. In the figure, 2 is a hub, 3 is a subscriber, 33 is a BS tuner, 34 is a channel selection remote control, 336 is a remote control receiving circuit, 337 is a CPU, 338 is a selection signal decoding circuit, 340 is an I10 control circuit, and 36 is an interface. Shows the circuit.

Claims (1)

[Claims] CATV broadcast signals of a large number of frequency-multiplexed channels are transmitted from a head end to a hub, and CATV broadcast signals of a small number of channels among the large number of frequency-multiplexed channels are transmitted from the hub to a hub.
A CATV receiver that transmits a broadcast signal to a subscriber and receives any of the multiple channels of CATV broadcast signals in a receiving channel of the receiver that receives the broadcast waves of the plurality of channels or the broadcast waves of the plurality of channels. a selection command means for giving a command to select one of the CATV broadcasts of a large number of channels; and when the selection command means gives a command to select one of the broadcast radio waves of the plurality of channels, the broadcast radio wave of that channel is In response to receiving a command to select one of the multiple channels of CATV broadcasting by the receiver, the receiver is set to the certain receiving channel, and the selected CATV broadcasting is performed on the receiving channel. An automatic channel setting device for a CATV receiver, comprising control means for providing a reception selection signal to the hub so that broadcasts are received.