JPH0568251A - Satellite receiver - Google Patents

Abstract

PURPOSE:To make the writing-in of individual information smooth ands to reduce the burden of a user by allowing the user to input all contracting broadcast enterprisers in a receiver at the time of a contract of updating the contract and writing-in individual information of all the contract broadcasting channels. CONSTITUTION:This receiver is provided with a means with which the user inputs one or plural contract broadcasting stations, etc., at the time of contracting with the broadcasting enterpriser and a means automatically synchronizing next specified contracting broadcasting channels so as to allow the broadcasting enterpriser to writing-in individual information about receiving permission transmitted with a broadcasting electric wave and writing-in individual information about all the contracting broadcasting channels. A means 35 displaying that writing individual information is finished to all the contracting broadcasting channels is provided. Consequently, a microcomputer 33 can judge to synchronize a frequency with all the contracting channel. Thus, even when the number of satellite broadcasting enterprisers or subscribers are increased, the user can smoothly write-in individual information and the burden of the user can be reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a satellite broadcast receiver.

[0002]

2. Description of the Related Art Generally, a pay broadcasting system such as satellite broadcasting employs a scramble system in which a broadcast program signal is disturbed and transmitted in order to keep the broadcast program signal confidential.

[0003] In addition to the scrambled program signal, information necessary for descrambling, information on charge storage, and the like are transmitted from the broadcasting station side in the pay broadcasting system as related information. On the receiver side, a pay decoder (descrambler) is required to descramble, and the program signal is descrambled according to the contract conditions (individual information) of each subscriber based on the above related information. The subscriber pays a fee to the broadcasting station through a transfer to a financial institution, etc. However, if the contract is changed or abolished, the related information will not be changed or transmitted.

In the case of JSB (Japan Satellite Broadcasting), if a user contract (3, 6, 12 months) is applied, JS
B is a descramble that writes individual information (contract details of each user: programs that can be viewed, contract deadline) in RAM.
Deliver the decoder to the user. Therefore, the user only needs to turn the power on for viewing on the receiver.

By the way, when the contract period with the user is over and the contract is renewed, the broadcasting station does not have each user send the above-mentioned decoder and newly write the individual information, but this time, the individual information is broadcast radio wave. Multiplex and decoder R
We are rewriting to AM. The transmission cycle of the broadcast wave in which the individual information is multiplexed requires one hour for 400,000 subscribers, if simply considered.

[0006] In the case of CS (communication satellite), it is expected that the number of broadcasters for general household broadcasting will increase in the future, and all of these will be pay broadcasting systems using a scramble system. Moreover, since these receivers are sold by the receiver manufacturer in a format with a built-in decoder, the individual information is pre-registered with RA.
Writing to M is difficult. Therefore, the writing of individual information must rely on writing by broadcast waves.

[0007] Here, it is necessary to consider that the frequency varies from broadcaster to broadcaster, so that a user with a large number of contracts tunes to the frequencies of all the contracted broadcasters one by one to obtain individual information. It was very difficult for users to write because they had to wait for writing.

[0008]

As described above, it is very troublesome for a user with a large number of contracts to write the individual information in the RAM in the receiver, so it is desirable that this be automatically performed by the receiver. ..

[0009]

According to the present invention, a user inputs all contracted broadcasters to a receiver at the time of contract or contract renewal, and the microcomputer makes a judgment to tune the frequency to all contracted channels to obtain individual information. It is characterized in that it enables writing.

If the descramble enable / disable flag of the decoder in the receiver is enabled, it is determined that the individual information has been written, the process proceeds to the next contract channel, and it is determined that all contract channels have been completed, The feature is that the end display is performed.

[0011]

The satellite broadcast receiver according to the present invention is capable of automatically writing individual information of the user and displaying the end of writing.

[0012]

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

First, referring to FIG. 1, the scramble system for pay broadcasting will be described.
It is composed of a CM encoder 1 and a scrambler 2, and a user's receiving side is composed of a PCM decoder 1 ″ and a descrambler 2 ″.

More specifically, on the transmission side, the program signal S _B is scrambled by the encryptor 11 and the scramble key circuit 3 having a short update period. Furthermore, the signal of the scramble key circuit 3 and the related information signal of the related information circuit 4 are input to the encoder 5 and digitally multiplexed, and the related information signal is changed by the key signal of another work key circuit 6 having a long update period. Scrambled. Furthermore, the key signal of the work key circuit 6 having a long update period and the individual information signal of the individual information of the circuit 7 are input to the encryptor 8 and digitally multiplexed,
The individual information signal is scrambled by the key signal of the master key circuit 9 unique to the subscriber. The scrambled program signal S _B ′, the common information signal S _C ′ and the individual information signal S _P ′
Is multiplexed (2.048 Mbps bitstream),
You will be riding the broadcast wave.

On the other hand, the receiving side deciphers into a cipher by the reverse procedure of the transmitting side. Using the key signal unique to the subscriber of the master key circuit 9 ″, the decoder 5 ″ outputs the key signal of the work key circuit 6 ″ and the individual information of the individual information signal of the circuit 7 ″. The key signal of the work key circuit 6 ″ is used to output the key signal of the decoder 5 ″ radio wave scramble key circuit 3 ″ and the related information signal of the related information circuit 7 ″. The related information signal of the related information circuit 7 ″ is compared with the individual information signal of the individual information circuit 7 ″ previously written in the RAM in the comparison circuit 1.
0 "is compared, and if they match, the scramble key 3" and the decoder 11 "descramble the program signal S _B 'to output the original program signal S _B.

Next, an embodiment of the CS / PCM voice broadcasting receiver will be described with reference to the block circuit diagram of FIG. 2. The radio waves (12.5 to 12.75 GHz band) transmitted from the satellite are as follows.
The frequency is converted to 1 GHz band by the antenna converter 21 and input to the channel selector 22 to obtain 134.26 MHz.
Alternatively, the frequency is converted to an intermediate frequency of 402.78 MHz. The channel selector 22 converts only the frequency band of the satellite channel (transponder) selected by the operation switch (SW) 34 into an intermediate frequency (band: 27 MHz),
It is input to the MSK demodulator 23.

The above MSK (Minimum Shift)
Keying modulation is phase continuous FSK (Fre).
It has a frequency shift keying of 0.5 and a modulation index of 0.5, and therefore the error rate is less deteriorated by a non-linear amplifier such as a satellite transponder due to phase continuity. Since the side rope is small, there are advantages such as little inter-channel interference, and it is a method suitable for satellite transmission.

The MSK modulated signal S (t) is expressed by the following equation 1
As shown in

[0019]

## EQU1 ## S (t) = A _I cos (πt / 2T) cos2πfct + A _Q sin (πt / 2T) sin2πfct

However, fc is a carrier frequency, 1 / T is a bit rate, and A _I and A _{Q are} transmission side modulation signals.

Therefore, when the data is "1", fc + 1 /
When it is 4T and the data is "0", it becomes fc-1 / 4T.

The MSK demodulator 23 reproduces the digital data (12.288 Mbps on the I and Q axes) and the clock signal (12.288 MHz) on the transmission side by using the synchronous detection method having a good error rate characteristic. The Viterbi decoder 24 in the stage performs Viterbi decoding. It is convolutionally coded on the transmission side and is one of the decoding methods for this code.

The convolutional code / Viterbi decoding method is used in satellite communication as an error correction method having a high correction capability for random errors. Viterbi decoding accumulates a certain amount of a signal decoded on the receiving side and then receives it. The signal that is
Combination of that signal and accumulated signal (state transition)
More specifically, this is a decoding (maximum likelihood decoding) method that is performed by estimating the most likely state.

The data of 12.288 Mbps error-corrected by the Viterbi decoder 24 described above is output, and the demultiplexer 2 together with the clock signal (12.288 MHz).
Input to 5. In the demultiplexer 25, the microcomputer 33 judges by the operation switch 34, and one of the low-order channels (2.048 Mbps = 1 frame) 1 to 6 is selected, and the PCM demodulator 2
7 and the decoder (descrambler) 28.

The PCM demodulator 27 performs various signal processing on the 2.048 Mbps PCM signal selected by the demultiplexer 25, and removes an extra frequency spectrum generated by sampling by the digital filter 30 via the selector 29. , D / A converter 31 outputs a left (L) audio signal, and D / A converter 32 outputs a right (R) audio signal. The PCM demodulator 2
The difference between 7 and the decoder (descrambler) 28 is whether or not pay scramble broadcasting can be descrambled, and the basic demodulation is the same. By the way, the user inputs the channel with which the receiving contract is made at the time of contract or contract renewal. The procedure is as shown in Table 1 below.
Will be in order. By using the preset memory (in the receiver), work of ,,, can be done with one touch.

[0026]

[Table 1]

Incidentally, JCSAT is Japan Communication Satellite Co., Ltd., and SCC is Space Communication Co., Ltd. Currently, there are 6 licensed broadcasting stations (2 transponders, 3 channels in one frame are assigned to 1 company), and 18 programs (3 × 6 channels) are broadcast in B mode stereo. Therefore, it is necessary to write the individual information 18 times even in the CS / PCM music broadcast alone. There are 1 transponder and 1 broadcasting station for CS video broadcasting, and 6 broadcasting stations are currently approved.
Therefore, it is necessary to write the individual information 24 times in total for the CS / PCM music broadcast and the CS video broadcast.

The transponder selection and the frame selection correspond to the channel selector 22 and the demultiplexer 25 in the receiver block circuit diagram of FIG. 2, but the satellite selection is JCSAT.
Since the azimuth angle and elevation angle differ between SCC and SCC, antenna 2
The direction of 1 is changed mechanically by the operation switch 34,
In addition, the polarization plane of the broadcast radio wave may differ even within the same satellite, and the polarization plane of the antenna converter 21 is also switched by the operation switch 34.

Referring to FIG. 3, the satellite broadcast receiver of the present invention will be described with reference to the flow chart of the microcomputer. At the time of contract or renewal contract, the user inputs the channel with which the reception contract is concluded (1).

First, the microcomputer 33 detects whether or not the decoder 28 is connected to this system, and if it does not exist, this processing is not performed and the routine proceeds to the next routine to return to the normal operation (2).

After that, since the individual information can be written, the data is sent to the channel selector 22 and the demultiplexer 25 so as to synchronize with the broadcast channel of the contract broadcaster (3).

Next, the descrambling flag in the decoder 28 is checked (4), and if it is judged that the individual information has been written, the process proceeds to the next contract channel and the same processing is performed (5). ..

When it is determined that the individual information has been input for all the contracted broadcasters (broadcasting stations), the end display is displayed on the display device 35 (6) to inform the user.

[0034]

According to the present invention, even if the number of satellite broadcasters or subscribers increases in the future, individual information can be written smoothly and the burden on the user can be reduced.

[Brief description of drawings]

FIG. 1 is a block circuit diagram of a scramble system in pay broadcasting.

FIG. 2 is a block circuit diagram of a CS / PCM audio broadcast receiver according to an embodiment of the present invention.

FIG. 3 is a flowchart by a microcomputer of the satellite broadcast receiver of the present invention.

[Explanation of symbols]

 1 PCM Encoder on Transmission Side 1 ″ PCM Decoder on Reception Side 2 Scrambler on Transmission Side 2 ″ Scrambler on Reception Side 21 Antenna Converter 26 Viterbi Decoder / Demultiplexer IC 30 Digital Filter

Claims (2)

[Claims] [Claim 1] A means for a user to input one or more contracted broadcasting stations, etc. when making a contract with a broadcasting company, and automatic so that the broadcasting company can write individual information regarding reception permission transmitted by broadcast waves. A satellite broadcasting receiver characterized in that it has means for synchronizing the following designated contracted broadcasting channel and writing individual information for all contracted broadcasting channels. 2. The satellite broadcast receiver according to claim 1, further comprising means for displaying that the writing of the individual information has been completed for all the contracted broadcast channels.