KR19990036286U - Combined broadcasting receiver and transmitter of cable TV company - Google Patents

Abstract

The present invention relates to a broadcast signal reception and transmission apparatus provided on the cable television operator side, and more particularly, to provide a composite broadcast reception and transmission apparatus implemented to transmit a received digital satellite broadcast signal to a subscriber in a digital form. The composite broadcasting reception and transmission apparatus according to the present invention is a digital satellite broadcasting reception and decoding to decode the received digital satellite broadcasting signal by quadrature phase shifting (QPSK), and to output and convert the decoded data by quadrature amplitude modulation (QAM). It includes a transmitter as many as the number of repeaters, and comprises a mixer for mixing the provided analog cable television and terrestrial broadcast, and the digital broadcast signal output from each digital satellite broadcast receiver and transmitter for each frequency band and outputs the cable. Therefore, the public channel can be prevented from being wasted, and the CA can be accommodated.

Description

Combined broadcasting receiver and transmitter for cable TV company

The present invention relates to a composite broadcasting receiver and a transmission apparatus provided on the cable TV (hereinafter referred to as CATV) operator side, and in particular, CATV operators implemented to transmit digital satellite broadcast signals received from broadcasting stations to subscribers The present invention relates to a composite broadcast receiving and transmitting apparatus on the side.

The broadcast receiving and transmitting device provided in the CATV service provider was implemented to provide only subscribers with analog cable TV (hereinafter referred to as CATV) and terrestrial broadcasting. However, with the advent of digital satellite broadcasting in recent years, an analog / digital satellite broadcasting receiver has been provided in the existing broadcasting receiver and transmitter to provide subscribers with new media broadcasting combining CATV / terrestrial / satellite broadcasting.

FIG. 1 is a schematic block diagram of an apparatus for receiving and transmitting a composite broadcast provided by a cable TV provider in order to provide a subscriber with the above-mentioned new media broadcasting, wherein one analog / digital antenna per antenna 101, 102, and 103 is provided. Satellite broadcasting receivers 111, 112, and 113 are connected to receive a program transmitted through satellite broadcasting. At this time, the analog / digital satellite broadcasting receivers 111, 112, and 113 for each channel are fixedly operated to receive only one channel of satellite broadcasting. Each of the analog / digital satellite broadcast receivers 111, 112, and 113 modulates and decodes the received digital satellite broadcast signal to output a baseband video signal and an analog audio signal (A / V) signal. Here, the baseband video signal means a video signal before modulation. The A / V signals output from the analog / digital satellite broadcasting receivers 111, 112, and 113 are transmitted to the RF modulator 120.

When the A / V signal is transmitted from each analog / digital satellite broadcasting receiver (111, 112, 113), the RF modulator 120 performs up-converting to a channel designated by the operator and transmits the cable through a cable. Analog CATV broadcasting and terrestrial broadcasting are transmitted by cable as it is.

As can be seen in the structure shown in FIG. 1, the composite broadcasting reception and transmission apparatus provided in the existing CATV service provider has one satellite broadcasting receiver fixed to one channel for each channel when public hearing is performed. Channel waste is severe, and it is difficult to accommodate a conditional access system (hereinafter referred to as CAS) due to demodulation and transmission of a received digital satellite broadcasting signal into an analog signal. CAS is a service that adds the concept of subscribers to TV broadcasting so that only subscribers who pay a fair subscription fee can watch the program. In other words, it is a service that provides the program only to the subscriber who paid the fee determined for each program.

The present invention has been made to solve the above-mentioned shortcomings, and an object of the present invention is to provide a composite broadcast reception and transmission apparatus of a CATV service provider, which is implemented to encode a received digital satellite broadcast signal in a digital form and provide it to a subscriber. .

In order to achieve the above object, the composite broadcast reception and transmission apparatus according to the present invention is a composite broadcast reception and transmission apparatus provided on the operator side of a cable television capable of receiving a digital satellite broadcast signal transmitted through a repeater. Tuned digital satellite broadcasting signal, quadrature phase shift (QPSK) demodulation, channel decoding, quadrature amplitude modulation (QAM) of the signal output from the channel decoding unit, and upconverting to the channel designated by the operator for encoding A digital satellite broadcasting receiver and transmitter configured as a repeater; And a mixer for mixing a cable television broadcast signal and a terrestrial broadcast signal capable of transmission, and a digital broadcast signal output from each digital satellite broadcast receiver and transmitter for each frequency band and outputting the cable through a cable connected to the subscriber.

1 is a block diagram of an apparatus for receiving and transmitting a composite broadcast provided on a conventional cable TV provider side.

Figure 2 is a block diagram of a composite broadcast receiving and transmitting apparatus provided on the cable TV operator side according to the present invention.

<Description of the symbols for the main parts of the drawings>

200, 210, 220: First to N digital satellite broadcasting receivers and transmitters

201: control unit 202: tuner unit

203: Analog-to-digital converter (ADC) 204: QPSK demodulator

205: QAM modulator 206: Upconverter

230: Mixer

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a block diagram of a composite broadcast reception and transmission apparatus provided on the CATV operator side according to the present invention, and digital satellite broadcast reception and transmission unit 200, 210 for outputting QPSK demodulation and QAM modulation to be applied to the digital satellite broadcast signal. 220 is allocated to one repeater for each repeater, and the digital signals output from the first to N digital phase broadcast receiving and transmitting units 200, 210 and 220 and CATV broadcasting and terrestrial broadcasting provided in a conventional manner are provided. It is composed of a mixer 230 for outputting a cable to be mixed by band and transmitted to the subscriber side.

In particular, the digital satellite broadcasting receiving and transmitting unit 200, 210, and 220 are channels for satellite broadcasting programs received using the tuner unit 202, the analog / digital converter (ADC) 203, and the QPSK demodulator 204, respectively. Perform decoding and perform encoding on the decoded satellite broadcast program using the QAM modulator 206 and up-converter 207.

The composite broadcast reception and transmission apparatus of the CATV provider configured as described above is operated as follows.

First, when a digital satellite broadcast signal is received through an antenna, it is transmitted to the first to Nth digital satellite broadcast receivers and transmitters 200, 210, and 220, respectively.

Each satellite broadcast receiver and transmitter 200, 210, 220 tunes the applied satellite broadcast signal in the tuner unit 202. Tuning control of the tuner unit 202 is performed by the control unit 201. The tuned signal is digitally converted through the ADC 203 and transmitted to the QPSK demodulator 204. The QPSK demodulator 204 demodulates the applied digital signal into a signal having a frequency band of 24 MHz, and forwards the demodulated signal forward. Error correction is performed by the Forward Error Correction (FEC) method, and an additional bit is added and output.

When channel decoding for the received digital satellite broadcasting is performed as described above, it is transmitted to a Quadrature Amplitude Modulation (QAM) modulator 205 and modulated to a 6 MHz frequency band suitable for cable transmission. QAM is done in the same way as before. In other words, two carriers having the same frequency and 90 ° out of phase with each other are amplitude-modulated into two discrete signals each having a finite value, and then added by digital modulation. The QAM modulated satellite broadcast signal is transmitted to the up-converter 206.

The upconverter 206 upconverts the QAM modulated signal to the channel designated by the operator. For example, when the repeater channel of the received satellite broadcast signal is 2CH and the cable channel designated by the operator is 52CH, the satellite broadcast signal applied by QAM modulation is converted to 52CH and outputted. At this time, the additional bits added during QPSK demodulation are deleted, and the repeater channel information and the cable channel information are inserted into the additional bit region and transmitted. With this QAM modulation and up-conversion, an encoded signal for channel decoded satellite broadcasting is output. The output signal is sent to the mixer 230.

The mixer 230 is a signal obtained by mixing the digital broadcast signal and the existing CATV / terrestrial broadcast signal, which are output through channel decoding and encoding processes from the digital satellite broadcast receivers 200, 210, and 220, for each frequency band. Is transmitted to the subscriber through the existing cable.

As described above, the present invention implements the composite broadcast reception and transmission apparatus provided on the cable TV operator side to decode and transmit the received digital satellite broadcast signal into a digital signal having a frequency band suitable for cable transmission. By supplying all the channels to subscribers, channel waste can be prevented as before, and the advantages of digital broadcasting are transmitted to the subscribers as it is, thus facilitating the introduction of CAS.

Claims (1)

In the composite broadcast receiving and transmitting apparatus provided on the operator side of a cable television that can receive digital satellite broadcast signal transmitted through a repeater, Means for tuning the received digital satellite broadcast signal, performing quadrature phase shift (QPSK) demodulation, and performing channel decoding; quadrature amplitude modulation (QAM) of the signal output from the channel decoding means, and upconverting to a channel designated by the service provider. A digital satellite broadcasting receiver and transmitter configured as means for encoding by the repeater number; And a mixer for mixing a cable television broadcast signal and a terrestrial broadcast signal capable of transmission, and a digital broadcast signal output from each of the digital satellite broadcast receivers and transmitters for each frequency band and outputting the signal through a cable connected to a subscriber. Broadcast receiving and transmitting device.