JPH04200018A - Channel selection device - Google Patents

Abstract

PURPOSE:To change a channel automatically when the broadcast turns to a changeable are by changing a reception tuning frequency when an 8-th register bit of an audio signal changes from 0 to 1. CONSTITUTION:A channel selection device has a channel selection function receiving an ultrahigh frequency signal and is tuned to a television signal FM- modulated included in the ultrahigh frequency signal in a way of configuration that while an audio signal in a frequency-modulated television signal is set in compliance with the standards of a satellite television broadcast or the standards including a control signal of the same standards or equivalent, when a specific control bit in the audio signal in the received television signal is 1 (or 0), the tuning frequency is changed so as to allow the channel selection function to be tuned to the frequency-modulated television signal whose control bit is not 1 (or 0). Thus, when a viewer not possessing a subscription broadcast receiver cannot view a video image and an audio signal, the state is detected and the channel is changed automatically.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates primarily to a channel selection device for a receiver capable of receiving satellite broadcasting.

Conventional technology The report (hereinafter referred to as the report) to the Telecommunications Technology Council's Consultation No. 17 states that the 8th (hereinafter referred to as R6) of the audio recipe for paid broadcasting (scrambled broadcasting) is "1". Using this signal,
Satellite television broadcasting (broadcasting based on the contents of the report in March and December 1982; hereinafter referred to as BS)
Abbreviated as TV broadcast. ), the BS tuner receives R
It is being considered to add a display corresponding to either "0" or "IJ" in No. 3.

Problems to be Solved by the Invention From a certain point on, video and audio signals become so-called paid broadcasting, and when both the picture and sound become distorted, viewers who do not own a paid receiver (descrambler) will be forced to , the tuning frequency must be changed to a non-scrambled chancel.

SUMMARY OF THE INVENTION In view of the above-described problems, an object of the present invention is to provide a channel selection device that can automatically change the channel when broadcasting becomes pay broadcasting.

Means for Solving the Problems In the present invention, in order to achieve the above objects, R6 is rQ,
- When the frequency changes by 14 meters, the reception tuning frequency is changed and the unpulled channel is selected.

According to the present invention, when R6 changes from "0" to "1", a pulse is generated in parallel with the up/down tuning keys, and the tuned frequency is changed by this pulse. Channels that are not available can be automatically selected.

EXAMPLE An example of the present invention will be described below with reference to FIGS. 1 to 4.

FIG. 1 is a block diagram of one embodiment of the present invention.

In the figure, 1 is a high frequency amplifier, whose input is a BS-IPF signal (approximately IGHz band); 2 is a mixer; 3 is a local oscillator; 4 is a frequency divider that divides the output of the local oscillator 3;
5 is a PLL circuit, and 6 is a crystal oscillator, which oscillates the reference frequency of the PLL.

12 is an intermediate frequency amplification circuit having a band of about 27 MHz.

13 is an FM detection circuit, and 14 is an audio demodulation circuit.

The operation of the audio demodulation circuit 14 is based on the audio signal of BS television broadcasting (a signal that conforms to the content of the Telecommunications Technology Council report dated December 10, 1981, and the standard is, for example, the Television Society of Japan's No. 1.37, Tane. 5, P, 366 to 374), and has a configuration in which the range bits shown in FIG. 2 can also be taken out. 15 is a control code detection circuit that determines whether the eighth range bit R8 is "1" or "0", and transmits its output to the pulse generation circuit 83 (see FIG. 3) in the control logic 8L. .

The program 8 is composed of a control logic 8L and a counter 8C, and can be easily implemented using a microprocessor. 9 is a set of up and down channel selection keys; 10
is a remote control transmitter that has both 10-key and up/down key functions. 11 receives a remote control signal;
This is a receiving section that performs binary signal conversion. 16 is a circuit that detects local frequency tuning, and using this circuit, AF
A C circuit can be constructed.

Note that if the drift of the B S-IF signal is small, this tuning detection circuit 16 is unnecessary.

In the above configuration, to describe the normal operation, when the remote control transmitter 10 is operated to specify, for example, the 11th channel of BS broadcasting, the control logic 8L decodes this and uses the frequency divider to tune at that frequency. 4 through the counter 8C.

As shown in FIG. 3, if the control logic 8L sends the division ratio to the counter 8c three times in 4 bits, the frequency divider 4
Digit division ratio can be set. The setting of this frequency division ratio may be four digits. From the control logic 8L, the counter Bc-= receives 4 hints of data and its timing signal. If there is no signal on the 11th channel, the control codes -b shown in FIG. 2(C) output from the audio demodulation circuit 14 become "0" or noise, and it can be determined that there is no signal. Also, it can be determined that there is no signal by the fact that the 2,048 Mb bit stream in the output of the audio demodulation circuit 14 is out of synchronization. Therefore, after the channel selection operation, for example, 0.5~
This means that it can be determined whether there is no signal or not in one second. If you select Chumpful with the selection keys 9 and 10, you can leave it as is.

If the channel selection key 9 or the up or down key of the remote control transmitter 10 is pressed, the control logic 8L
．． 2 amps or down pulses at 5 second intervals
The counter 8C outputs the frequency division ratio of the upper channel by two channels, and sets the frequency divider 4 to that frequency division ratio. This is because Japanese BS television broadcasts are 1.3. Since only the 15 odd-numbered channels are internationally assigned and there is no need to tune to even-numbered channels, the logic of the control logic 8L may be configured in this manner. Note that the conversion logic 8■ in the counter 8C compares the two AMBU pulses with the current division ratio (3 digits) in the counter 8C and determines that it is two channels higher, that is, if the current channel is 11 in this example. A frequency division ratio of 13 channels is formed and transmitted to the frequency divider 4. The operation of the conversion circuit 8■ can be realized by the control logic 8L, and in reality, the control circuit 8L, the counter 8C1, the conversion logic 8■, the gate 81.
Although the pulse generation circuits 82 and 83 can be collectively processed by one microprocessor, they are shown separately in FIGS. 1 and 3 for the sake of explanation. When the channel is down, a pulse is sent from the control logic 8L to the 2-digit conversion logic 8■.
The frequency division ratio of 9 channels is transmitted from the counter 8C to the frequency divider 4. The counter 8C and the frequency divider 4 are connected by a total of 5 or 6 lines including 4-bit data and one or two types of pulses indicating timing.

Next, the operation when R8 is "1" will be described using FIG. First, let's assume that in channel 13, initially R6=0 and R6=1 from time T1 to T2, the control code detection circuit 15 detects R8=1, and the pulse of φ1 is sent to the pulse generating circuit as shown in FIG. Tell 83. Pulse φ
, (that is, at time T1), the pulse generating circuit 8
3, and the detection output is transmitted from the pulse generation circuit 83 to the conversion logic 8■ via the N○R gate 81 at 0.5 second intervals, and as described above, the detection output is transmitted to the conversion logic 8V and the counter 8C.
operates, and the frequency divider 4 is set to a frequency division ratio of 15 channels. On the other hand, from the control code detection circuit 15, a signal φ2 indicating that the signals are in tune is transmitted to the control circuit 8L. It goes without saying that the output of the tuning detection circuit 16 may be used instead of this signal φ2. T, a little after time T1. 1, frequency divider 4 is set to 12 channels, and φ
2 is in an out-of-tuned state (R8 is 0 in FIG. 4). Time T
At l02 (temporarily assumed to be 1.0 seconds after T1), it tunes to channel 15, and if R8 is [1], φ1 falls again, and by repeating the above operation, time T is reached.

At 3 o'clock, it became 16 nayan mahara and R8 was φ1. φ2 is also in an out-of-synchronization state at time T,. 4 to tune to channel 1, and R, -〇, the channel is fixed here. The same applies below. If channel 1 is also R8-1, 3
channel. In the "B5-4" era, broadcasting satellites used eight odd-numbered channels numbered 1 to 15.

If R8=1 for all 8 channels, it is estimated that this is not possible, and it will stop at some channel. If all channels are R5-1, no one will be tuned in, but in that case there will be no problem because the viewer will switch to something other than BS, such as terrestrial broadcasting, CATV, or C5 broadcasting.

The above explanation is for the case where R,=0 changes to 1, but when the 13th channel is specified directly with the 10 key, the 4th
Shortly before T1 in the figure, φ2 enters the tuned state (rl,), and T
If R8=1 is detected at 1, the same operation as described above is performed and the channel is settled on 1 channel.

On the other hand, if you press the transmit key 9 or the up key on the remote control transmitter 10, if you are tuned to channel 13 and
Even when moving to the 5th channel, R6=1 is detected and the channel is settled on the 1st channel. Tuning key 9 or remote control transmitter 10
If you press the down key - If you are tuned to channel 13 and move to channel 11, if channel 11 is R6-0, it will settle down to channel 11. That is,
If R,=0 changes to 1 in the middle of the channel, the channel with R11=O is searched and tuned. If the channel is specified using the 10 key and the amp key, R8-
It sequentially tunes to the channels two channels above channel 1 and settles on the channel with RI+=0. In the case of the down key, tune down the channels below by 2,000 yanfuls of the R, -1 channel to 12 I + [ and settle on the channel with RP = 0, and select the IO key and set the channel's RIl to 11. ．． At this time, whether to move F-1 or move downward is a matter of design of the control rosin 8L.

R8 has 4 types of W in A mode (if voice 4: F+N)
, There are two types in B mode, or 4 (, ", , Z is 2) types of RIl's AND is the output of the control code detection circuit 15, or their logical sum is the output of the control code detection circuit 15. This is a design matter. R8 in FIG. 4 is the control code detection circuit 1.
5 indicates logical product or logical sum L7.

In addition, using φ2 of the output of the control code detection circuit 15, if φ2 does not become in tune even after a certain period of time has passed after channel setting, the frequency division ratio of the frequency divider 4 is set to 2 channels up or down. It is also known to operate the control logic 8L to skip empty channels. Therefore, °“
BS-3", if broadcasting is only on 3 channels, if Re = 1 on 1 channel, the remaining 2
Needless to say, it is necessary to tune into one of the channels.

Although BS reception has been described below, broadcasting using C3 (communication satellite) is also planned. Since the frequencies and bands of BS and C5 do not completely match, the control
8L, the operator has to set it to determine whether it is BS or C3), and in the case of C3, the frequency division ratio is different from that of BS. Note that in C3, the channels are continuous (the polarization has a difference between H and V), so the above-mentioned operation needs to be performed for each channel. However, it can be realized with the same circuit configuration. If the control logic 8L is configured with a microprocessor, it can be handled by software processing.

The audio signal has been described above, but the above-mentioned consultation 1
In No. 7, the control signal b1□ shown in FIG. 2(C) is used to determine whether or not the video signal is scrambled.

Therefore, R3 as the output of the control code detection circuit]5,
The logical sum or logical product of b12 is applied to the pulse generating circuit 8 of FIG.
If you tell 3, you can choose unscrambled channels, including video.

Note that this invention can be commonly used for signal receivers that use BS television broadcast video and audio or only audio;
It is not limited to tuners. In addition, when audio 3 and audio 4 in A mode are used independently, R6 of the output of the control code detection circuit 15 that is transmitted to the pulse generation circuit 83 in FIG.
It is also possible to set R to be the AND or OR of R corresponding to audio 3 and audio 4, and to sequentially search for unscrambled audio 3 and audio 4 channels.

Effects of the Invention According to the present invention, when a viewer who does not own a pay broadcast receiver (pay decoder) can no longer view video or audio, this is detected and the tuning frequency is automatically changed. There is no need to manually select the channel again.
It also has the advantage that it cannot be mistaken for failure.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a channel selection device in an embodiment of the present invention, FIG. 2 is a configuration diagram of an audio signal for explaining the operation of FIG. 1, and FIG. 3 is a block diagram of the main part of FIG. 1. 4 are time charts for explaining the operation of FIG. 1. l...High frequency amplification, 2...Mixer, 3
...Local oscillator, 4... Frequency divider,
5...PLL circuit, 6...Crystal oscillator, 7...LPF, 8...Control logic, 9...Tuition selection key, 10...Remote control transmitter, 12...Intermediate frequency amplification circuit, 13...
...FM detection circuit, 14...audio demodulation circuit, 15...control code detection circuit. Name of agent: Patent attorney Akira Kogai et al. 28 No. 1
Figure/Z/Z
/3 Figure 3 wJ4 Figure

Claims (2)

[Claims] (1) It receives an ultra-high frequency signal as input and has a tuning function that tunes to an FM modulated television signal included in the signal,
When the audio signal in the FM-modulated television signal is transmitted in accordance with the satellite television broadcasting standard or a standard that includes an equivalent control signal, when the television signal is received, a specific control bit in the audio signal is transmitted. When it is "1" (or "0"), the tuning frequency is changed and the control bit becomes "1".
A channel selection device characterized in that it is configured to tune to an FM modulated television signal that is not (or "0"). (2) Any one or more of the plurality of specific control bits of the audio signal in the FM-modulated television signal is "1" (or "
0''), the tuning frequency is changed to tune to an FM-modulated television signal in which the control bits are all ``0'' (or ``1''). The channel selection device described in 1.