JPS59174079A - Receiver - Google Patents

Abstract

PURPOSE:To receive plural scramble broadcast radio waves with a simple operation by providing a switching circuit to a receiver to switch plural descrambler units and switching the switching circuit in response to the operation of a channel selecting device. CONSTITUTION:A direct broadcast satellite DBS broadcast such as a satellite TV broadcast, etc. is received by an outdoor unit 2 and converted into the 1st IF of the UFH band to be applied to a turner 11. The tuner 11 converts the IF into the 2nd IF in response to the channel selecting action of a channel selecting device 12. At the same time, the 2nd IF signal is processed by an indoor unit 10. The output of a video amplifier 15 is applied to descramblers 16A-16C as well as to a switching circuit 17 respectively. While the sound signal processed by a PSK demodulating circuit 22, a D/A converter 24, etc. is applied to descramblers 25A-25C as well as to a switching circuit 26 respectively. Then the output of the device 12 is applied to a switch signal producing circuit 35, and the circuits 17 and 26 are switched by the output of the circuit 35. Thus each scramble broadcast radio wave can be received in response to the channel selecting operation of the device 12.

Description

[Detailed Description of the Invention] Industrial Application Field This invention is applicable to, for example, satellite television broadcasting.
Direct broadcast (satellite) broadcast receiver.

BACKGROUND TECHNOLOGY AND PROBLEMS In CATV broadcasting, a broadcasting company and a receiver enter into a reception contract, and only the contracting party can view the broadcast programs of the broadcasting company, and no one other than the contracting party can view them. Therefore, the broadcast signal is scrambled. In this case, the subscriber is provided with a descrambler unit to restore the scrambled television signal to its original state, but in TV broadcasting to C, programs are usually sent from one broadcasting company. Since this descrambler unit is a single unit, it converts the television signal into a broadcast radio wave in the SJ/F band and transmits it using a geostationary satellite, and sends it to each home. Satellite television broadcasting, which will make it possible to receive TV broadcasts in Japan, is on the way to becoming a reality. In the case of BS broadcasting such as satellite broadcasting, it is possible to receive broadcast waves from multiple broadcasting companies, so the scrambling method to ensure that only subscribers can enjoy broadcast programs differs depending on the purpose of each broadcasting company. become. Therefore, in order to enjoy all the programs of various broadcasting companies, each home needs a plurality of descramblers corresponding to each scrambling method.

In this case, it is possible to enjoy all the programs of each broadcasting company by installing multiple receivers with built-in de-nuggling units for each broadcasting company, one for each broadcasting company. However, if a plurality of receivers are installed in this way, the financial burden on the subscriber will be increased.

Therefore, we installed only one receiver and used a de-scrambler.
A method of manually switching the unit for each broadcasting company is possible. However, this method requires the receiver to switch the descrambler unit at the same time as the channel selection operation, and the complexity is unbearable.

Purpose of the Invention The present invention enables receivers who receive DBS broadcasts to receive a plurality of different scrambled broadcast radio waves as described above without imposing an excessive financial burden on the receiver and with simple operations. It provides something that can be viewed.

Summary of the Invention This FJA has multiple descramblers in the receiver.
A switching circuit is provided to switch the unit, and this switching circuit is switched according to the tuning operation on the tuning device.
The scrambling system of each broadcasting company [corresponding descrambler unit is automatically selected].

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings.

FIG. 1 shows a receiving system for SHF satellite television broadcast waves.

Here, the transmitted SHF signal is as follows. In other words, the television audio signal is converted into a PCM signal,
After this PCM audio data is divided into blocks every predetermined time and an error correction code is formed and added, this PCM audio data is processed using 5.73 MHz as a subcarrier frequency.
The CM signal is subjected to four-phase phase modulation and becomes a signal that occupies the high frequency side of the analog video signal as shown in Fig. 5) (F'
The signal has been doubled.

This S I-IF' broadcast wave is received by the receiving parabolic antenna (1) of the receiving system shown in FIG. The SHF band signal received by this antenna (1) is sent to the outdoor unit (2) as @1 intermediate frequency signal, for example, IG.
The frequency is converted into UH and F band signals of approximately Hz.

This UHF band signal is then supplied to the tuner old 1 of the indoor unit (101) through the coaxial cable (3).

This tuner 1ll)K is supplied with a tuning signal according to the viewer's tuning operation from the tuning circuit (121), and the broadcast wave (UHF signal) of the selected station is sent from this tuner aυ. 2 intermediate frequency signals.

This second intermediate frequency signal is supplied to the second intermediate frequency amplifier (3). The output of this second intermediate frequency amplifier 031 is F
M demodulation circuit ai; utc and F'M demodulation r, its FM3
The output signal is supplied to the output amplifier +151, and a video signal is derived.

The output of the FM demodulation circuit is passed through a bandpass filter (2
1), the audio subcarrier component is taken out, and this is supplied to the four-phase phase modulation circuit (221, where the audio PCM signal is demodulated and supplied to the digital decoder (sub)). In this decoder (23), after correctable errors in the PCM signal are corrected using an error correction code, the PCM signal is returned to the original time series. 4 Ru.

In this invention, a switching circuit is provided for switching the descrambler unit, but in this example, it is assumed that not only the video signal but also the audio signal is scrambled. A switching circuit σn for a video signal descrambler unit and a switching circuit for an audio signal descrambler unit [261
4 is provided.

Then, the video signal from the video amplifier aL3 is supplied to the switching circuit (1η), and a plurality of terminals corresponding to the number of broadcasting companies performing scramble broadcasting, in this example, three broadcasting companies A, Assuming that B and C perform scramble broadcasting, video signals are supplied to three terminals (31A), (31B), and (31C).
(31B) (31C) To pair wo7', C-(" terminal (
32A), (32B), and (32C) are provided, and the signals obtained at these terminals (32A), (32B, and 32C) are supplied to the switching circuit η. And the terminal (31A)
Between and (328) are terminals (3] i3) and (
There is a terminal (3IC) of company B between the terminal (32B) and (32C
), there are 0 companies with descrambler units (16A) for each scrambling method for video signals.
), (16B), and (16C) are respectively connected by f'L. In this example, these descrambler units (16A), (16B), (16C)
between terminals (318) (32A), terminals (3iB) (32
B) and between the terminals (31C) (32C), respectively, is optional depending on the requirements of the receiver.

Similarly, regarding the analog audio signal from the Al1) converter (24), this audio signal is transferred to the 11 switching circuit (24).
6) and three iC terminals (33A) (
33B) (33C) are supplied to these terminals (33A
)<33B (33C) and the paired terminal (34A) (
34B) The signal obtained at (34C) is connected to the switching (B) path (
26; be supplied. And the terminals (33A) (34A
) between terminals (3313) and (34B) of company A, and between terminals (3313) and (34B)
De-scrambler unit (25A) (25B) (25
C) is made to connect at the request of the recipient.

The switching circuit (Iη and (fi +261) is switched n7 in response to the tuning operation in the tuning device (12). That is, in this example, the signal corresponding to the tuning operation from the tuning device (121) is the switching signal. A switching signal corresponding to the selected channel is obtained by being supplied to the forming circuit (351), and the switching circuit qη and (26) are switched by this circuit. For example, when the channel selection device 1121 is a so-called synthesizer one-type device. , a signal indicating the division ratio of the variable frequency divider for setting the local oscillation frequency is supplied to the switching signal forming circuit 135), from which a code corresponding to the broadcasting company of the selected channel is obtained as the switching signal. For example,
Assuming that the 1st and 3rd channels are from company A, the 4th and 5th channels are from company B, and the 8th channel is from company 0, each company's code is obtained as a switching signal according to the selection of each channel. .

Therefore, the switching circuits αη and 12E9 are connected to the channel selection device (
When the first channel or the third channel is selected at 121, the terminals (32A) and (34A) are connected, and when the fourth channel or the fifth channel is selected, the terminal (32A) is connected to the terminal (32A) and (34A).
When the 8th channel is selected on the B) and (34B) sides, it is automatically switched to the terminals (32C) and (34C), respectively, and the descrambler units (16A) (1fiB) are connected to the terminals (32C) and (34C), respectively. (16C) is connected as described above, and the scrambled video and audio signals of the broadcast channel selected by the channel selection device (121) are automatically descrambled and converted into regular signals. The video signal and the audio signal are returned to the switching circuit f17) and obtained from C61.

Channel selection device (When another channel that is not scrambled broadcasting is selected in 121, a code different from the above is obtained as a switching signal from switching signal type 1 circuit G51, thereby switching circuit σD and white) are switched to take out the video signal and audio signal from the video amplifier (15) and D/A converter (2), respectively.

In this way, the video signal and audio signal obtained from the switching circuits 071 and 126) are output from the output terminals f181 and (126), respectively.
At the same time, the AM modulation times vj (4
From this, a signal modulated into the television broadcast wave of the empty channel of VHF' television broadcasting is obtained, and this is derived from the output terminal (4υVc).

If the signal obtained at this output terminal r edge is supplied to the antenna terminal of a television receiver that is popular in ordinary homes,
You can watch satellite TV broadcasts on this receiver's open channels.

As described above, between terminals (31A) and (32A), (3
If the receiver connects a descrambler unit between 1B) (32B) and (31C) (32C) according to his/her request, the receiver can receive the scrambled broadcast signal by simply selecting the channel. Since the broadcasts are descrambled, the receiver can easily watch multiple scrambled broadcasts with a simple operation.

In this example, one SHF receiving system was prepared, and the receiver connected a descrambler unit to it upon request, but the terminals (31A) (32A)
~(31c)(32C) Wora trf 7) Ko,
! Z <, multiple descramblers in one receiver
- The unit may be incorporated into an SHF receiver.

In addition, in the case of the example shown in the figure, the switching signal forming circuit symbol is the terminal (3
1N) (32A) to (3] and C) (32C), the user may be able to preset the switching code signal corresponding to the broadcast channel by the broadcasting company's descrambler unit connected between each of the channels. It can also be done.

Effects of the Invention In this invention, a descrambler is provided in the receiver.
A switching circuit is provided to switch the unit, and this switching circuit is automatically switched in response to the channel selection operation on the channel selection device, and the switching circuit is automatically switched in response to the channel selection operation on the channel selection device.
Since the scrambler is automatically selected, the receiver can easily enjoy a plurality of scrambled broadcasts by simply selecting a channel. Moreover, only one receiver body is required.

[Brief explanation of the drawing]

FIG. 1 is a system diagram of an example of a receiver according to the present invention, and FIG. 2 is a diagram showing a frequency spectrum for explaining a broadcast wave signal of satellite television broadcasting. (2) is an outdoor unit, (1α is an indoor unit, (1η
and (261 is a switching circuit of a descrambler unit).

Claims (1)

[Claims] DBS scrambled differently depending on the broadcasting company
(Direct Broadcast Satellite) A device that can receive broadcast radio waves, and must be equipped with a switching circuit that selectively switches between selective de-scrambler units that are compatible with different null-clamp systems depending on the broadcasting company. A switching signal is generated in response to the channel selection operation on the device, and this switching signal causes a de-scrambler corresponding to the scrambling method of the broadcasting station to be activated at the same time as the above-mentioned channel selection operation.
Receiver made available for unit selection.