KR100506733B1 - Analog/digital television tuner - Google Patents

Abstract

SUMMARY OF THE INVENTION An object of the present invention is to provide an analog / digital television tuner integrated with a single module to receive both analog television broadcasting (PAL) and digital television broadcasting (OFDM).

The analog / digital television tuner of the present invention,

An analog / digital television tuner for selectively receiving an analog television broadcast or a digital television broadcast from an antenna ANT, wherein a broadcast and a channel are selected from the RF signals from the antenna in accordance with analog / digital broadcast and channel selection; A tuner section 31 for making two signals inverted from each other from the IF signal generated by this selection and providing this balanced IF signal (+/- IF); An OFDM demodulator (32) which operates when digital broadcasting is selected and receives and demodulates one of the balanced IF signals (+ IF) from the tuner (31) by OFDM; And a PAL demodulator 33 which operates when an analog broadcast is selected and receives and PAL demodulates the other one of the balanced IF signals ± IF from the tuner unit 31. do.

According to the present invention, it is possible to receive both analog and digital broadcasts with one tuner, and does not require a separate signal splitter, thereby preventing loss of signals.

Description

Analog / digital TV tuner {ANALOG / DIGITAL TELEVISION TUNER}

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a television set and relates to a single conversion type analog / digital television tuner, in particular analog television broadcasting (PAL) and digital television broadcasting (OFDM). Method) by implementing a single module (single module) to be able to receive all, can receive both analog and digital broadcasts with a single tuner, and does not require a separate signal splitter signal loss The present invention relates to an analog / digital television tuner capable of preventing a problem.

In general, European terrestrial broadcasting is provided with analog television broadcasting of PAL (PAL) system and digital television broadcasting of Orthogonal Frequency Division Multiplexing (OFDM). Research and development of a receiver capable of receiving both of the two television broadcasts in one television broadcast receiver is in progress.

1 is a diagram illustrating the use of a conventional analog tuner and a digital tuner.

Referring to FIG. 1, when using a conventional digital tuner and an analog tuner at the same time, a digital tuner commonly called a set-top box is connected to an antenna ANT, and the analog tuner built into the television is connected to the digital tuner. Connect the tuner. In other words, it connects a set-top box with a digital tuner and a television set with an analog tuner.

In this connection, analog television and digital television broadcasts broadcast in Europe are received, and the digital set-top box receiving the digital signal re-modulates the demodulated signal back to an RF signal and provides the analog television set, or The AV signal can be output directly (e.g., scart).

However, since the use of two tuners to receive two broadcasts is a heavy burden on the seller or buyer side, the research and development of a technology for receiving two broadcasts on one tuner is in progress. In one of them, one television set includes both an analog tuner and a digital tuner, and a signal divider for distributing signals from one antenna to the analog tuner or the digital tuner, respectively. A scheme for receiving two broadcasts in a set has been proposed.

As such, there is an advantage in that one television set can receive both analog and digital broadcasts without a separate set-top box, but according to this method, both analog PAL broadcasts and digital OFDM broadcasts broadcast in Europe are received. In order to do so, it still requires two tuners, which leads to a problem that the TV takes up a lot of space and the price is quite high. Due to these problems, they are not actually manufactured.

The present invention has been proposed to solve the above problems, and the object thereof is to provide a single tuner by integrally implementing a single module to receive both analog television broadcasting (PAL) and digital television broadcasting (OFDM). The present invention provides an analog / digital television tuner capable of receiving both analog and digital broadcasts and preventing signal loss by eliminating the need for a separate signal splitter.

In order to achieve the above object of the present invention, the analog / digital television tuner of the present invention

In the analog / digital television tuner which selectively receives analog television broadcasting or digital television broadcasting from an antenna,

Among the RF signals from the antenna, a tuner for selecting a broadcast and a channel according to analog / digital broadcast and channel selection, and making two balanced signals out of phase from the IF signal generated by this selection to provide this balanced IF signal. part;

An OFDM demodulation unit configured to perform digital demodulation, and to perform OFDM demodulation upon receiving one signal (+ IF) among balanced IF signals from the tuner unit; And

PAL demodulation unit which operates when selecting analog broadcasting and receives PAL demodulation from the other of balanced IF signals from the tuner unit

Characterized in having a.

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

In the drawings referred to in the present invention, components having substantially the same configuration and function will use the same reference numerals.

2 is a block diagram of an analog / digital television tuner according to the present invention.

Referring to Fig. 2, an analog / digital television tuner according to the present invention is an analog / digital television tuner which is embedded in a television set and selectively receives an analog television broadcast or a digital television broadcast from an antenna ANT, which is the antenna. From the RF signals from, the broadcast and channel are selected according to the analog / digital broadcast and channel selection, and two balanced signals are phase-inverted from the IF signal generated by this selection to provide this balanced IF signal (± IF). An OFDM demodulation unit which is operated when a digital broadcast is selected and an OFDM demodulation unit which receives and demodulates one signal (+ IF or -IF) of the balanced IF signal (± IF) from the tuner unit 31. 32 and a PAL demodulator which is operated when an analog broadcast is selected and which receives PAL demodulation by receiving another signal (-IF or + IF) of the balanced IF signal (± IF) from the tuner unit 31 ( 33).

Meanwhile, the analog / digital television tuner of the present invention is commonly referred to as a network interface module (NIM), and the analog / digital television tuner of the present invention can be referred to as a hybrid OFDM module because it is manufactured as one module.

3 is a configuration diagram of the tuner unit of FIG. 2.

Referring to FIG. 3, the tuner unit 31 corresponds to a channel selected from an RF amplifier unit 31A for amplifying the RF signal from the antenna with a preset gain and an output signal of the RF amplifier unit 31A. RF filter unit 31B for passing a band, PLL unit 31C for controlling the generation of oscillation frequencies corresponding to broadcast and channel according to analog / digital broadcast selection and channel selection, and control of the PLL unit 31C An oscillator 31D for generating an oscillation frequency, a mixer 31E for mixing an RF signal from the RF filter unit 31B and an oscillation frequency from the oscillator 31D, and outputting an IF signal; Among the signals output from 31E, an IF filter section 31F for passing a preset IF band and an IF signal output from the IF filter section 31F are amplified with a preset gain, and the amplified IF signals By creating two signals that are phase inverted from each other And an IF amplifier 31G for outputting a balanced IF signal (+/- IF).

Hereinafter, the operation and effects of the present invention will be described in detail with reference to the accompanying drawings.

The analog / digital television tuner of the present invention receives an RF signal of 40 MHz-900 MHz from an antenna ANT to tune a selected broadcast channel, and performs OFDM demodulation or PAL demodulation according to the selected broadcast method. This will be described in detail below.

Referring to FIG. 2, the tuner unit 31 of the analog / digital television tuner according to the present invention is operated by an unillustrated control unit in an RF signal (frequency band of a television broadcast: 40 MHz to 900 MHz) from the antenna ANT. The broadcast and channel are selected according to the analog / digital broadcast and channel selection to provide a balanced IF signal having a preset frequency in the range of approximately 32 MHz to 40 MHz.

Here, the IF signal may be set to the same frequency within the range of 32MHz to 40MHz, respectively, analog television broadcasting and digital television broadcasting, or may be set differently for each broadcasting scheme, for example, analog television broadcasting and digital television Broadcast Mode The IF signal can be set to 36 MHz, or alternatively, the IF signal of analog television broadcast can be set to 40 MHz and the IF signal of digital television broadcast can be set to 36 MHz.

Then, when digital television broadcasting is selected, the OFDM demodulation section 32 of the present invention is operated by the first operation selection signal S01, so that one of the balanced IF signals (+/- IF) from the tuner section 31 is operated. OFDM signal is received and OFDM demodulated to provide an MPEG signal (SMPEG). On the other hand, when analog television broadcasting is selected, the PAL demodulation section 33 of the present invention operates by the second operation selection signal SO2, so that the other of the balanced IF signals (+/- IF) from the tuner section 31 is operated. One signal (-IF) is input to PAL demodulate to perform an AV signal (audio signal and video signal) SAV.

The tuner unit 31 will be described in detail with reference to FIG. 3.

First, according to analog / digital broadcasting and channel selection by a controller (not shown), the PLL unit 31C controls generation of an oscillation frequency corresponding to a broadcast and a channel, and accordingly, the oscillator 31D controls the generation of the oscillation frequency corresponding to the PLL unit 31C. Generate oscillation frequency under the control of.

For example, in an analog television broadcast, when the frequency of the IF signal is set to 40 MHz, and the center frequency of the selected channel is 85 MHz, the RF amplifier 31A of the tuner unit 31 according to the present invention is the tuner unit ( 31 amplifies the RF signal from the antenna to a predetermined gain and provides the same to the RF filter unit 31B, the RF filter unit 31B corresponding to a channel selected from the output signals of the RF amplifier unit 31A. The band (85MHz ± 4MHz) is passed through to the mixer 31E.

In addition, when the oscillation unit 31D generates an oscillation frequency of 125 MHz and provides the oscillation frequency to the mixer 31E, the mixer 31E is configured to generate the RF signal 85 MHz and the oscillation unit 31D from the RF filter unit 31B. The oscillation frequency (125MHz) is mixed and the 40MHz (125MHz-85MHz) IF signal is output to the IF filter unit 31F. Next, the IF filter unit 31F passes through a predetermined IF band (40 MHz ± 4 MHz) among the signals output from the mixer 31E and provides the IF amplifier unit 31G to the IF amplifier unit 31G. Amplifies the IF signal output from the IF filter part 31F with a preset gain, and generates two balanced signals out of phase from the amplified IF signal to output the balanced IF signal (± IF). The IF signal is PAL demodulated by the PAL demodulator 33 and then output as an AV signal (audio signal and video signal).

On the other hand, for digital television broadcasting, for example, when the frequency of the IF signal is set to 36MHz, and the center frequency of the selected channel is 300MHz, the RF amplifier 31A of the tuner unit 31 according to the present invention is the tuner. The unit 31 amplifies the RF signal from the antenna with a predetermined gain and provides the RF filter unit 31B to the RF filter unit 31B, and the RF filter unit 31B selects a channel selected from the output signals of the RF amplifier unit 31A. It passes through the corresponding band (300MHz ± 4MHz) to provide a mixer (31E).

In addition, when the oscillation unit 31D generates an oscillation frequency of 336 MHz and provides the oscillation frequency to the mixer 31E, the mixer 31E is configured to generate the RF signal 300MHz and the oscillation unit 31D from the RF filter unit 31B. The oscillation frequency (336MHz) is mixed and the 36MHz (336MHz-300MHz) IF signal is output to the IF filter part 31F. Next, the IF filter unit 31F passes through a predetermined IF band (36 MHz ± 4 MHz) among the signals output from the mixer 31E and provides the IF amplifier unit 31G to the IF amplifier unit 31G. Amplifies the IF signal output from the IF filter part 31F with a preset gain, and generates two balanced signals out of phase from the amplified IF signal to output the balanced IF signal (± IF). The IF signal is OFDM demodulated by the OFDM demodulator 32 and then output as an MPEG (Motion Picture Experts Group) signal.

According to the present invention as described above, for a television set (TV SET) receiving both the PAL method and the OFDM method, which are European terrestrial broadcasts, a hybrid OFDM module corresponding to the television tuner of the present invention is a digital OFDM module. It consists of a single conversion tuner, an analog demodulator and an OFDM demodulator that can be received, and the PAL / OFDM signal received by the single conversion tuner is output to each IF output. By connecting an analog demodulator and a digital demodulator, PAL broadcast signals are output as video and sound, and OFDM broadcast signals are output as MPEG signals.

According to the present invention as described above, by implementing a single module to receive both analog television broadcasting (PAL system) and digital television broadcasting (OFDM system), it is possible to receive both analog and digital broadcasting with one tuner In addition, since there is no need for a separate signal splitter, a signal loss can be prevented.

The above description is only a description of specific embodiments of the present invention, and the present invention is not limited to these specific embodiments, and various changes and modifications of the configuration are possible from the above-described specific embodiments of the present invention. It will be apparent to those skilled in the art to which the present invention pertains.

1 is a diagram illustrating the use of a conventional analog television tuner and a digital television tuner.

2 is a block diagram of an analog / digital television tuner according to the present invention.

3 is a configuration diagram of the tuner unit of FIG. 2.

Explanation of symbols on main parts of drawing

31 tuner section 32 OFDM demodulation section

33: PAL demodulator 31A: RF amplifier

31B: RF filter part 31C: PLL part

31D: Oscillator 31E: Mixer

31F: IF filter part 31G: IF amplification part

Claims (2)

In the analog / digital television tuner which selectively receives analog television broadcasting or digital television broadcasting from an antenna ANT, Among the RF signals from the antenna, a broadcast and a channel are selected according to the analog / digital broadcast and channel selection, and two balanced signals are phase-inverted from each other from the IF signal generated by this selection, so that this balanced IF signal (± IF) Tuner unit 31 to provide; An OFDM demodulator (32) which operates when digital broadcasting is selected and receives and demodulates one of the balanced IF signals (+ IF) from the tuner (31) by OFDM; And PAL demodulator 33 which operates when an analog broadcast is selected and receives PAL demodulation by receiving the other signal (-IF) among the balanced IF signals (± IF) from the tuner unit 31. And an analog / digital television tuner. The method of claim 1, wherein the tuner portion 31 An RF amplifier 31A for amplifying the RF signal from the antenna with a preset gain; An RF filter unit 31B which passes a band corresponding to a selected channel among the output signals of the RF amplifier unit 31A; A PLL unit 31C for controlling generation of an oscillation frequency corresponding to a broadcast and a channel according to analog / digital broadcast selection and channel selection; An oscillation unit 31D for generating an oscillation frequency under the control of the PLL unit 31C; A mixer (31E) for mixing an RF signal from the RF filter unit (31B) and an oscillation frequency from the oscillator (31D) to output an IF signal; An IF filter part 31F for passing a predetermined IF band among signals output from the mixer 31E; And An IF amplifying unit for amplifying the IF signal output from the IF filter unit 31F with a preset gain, and outputting this balanced IF signal (± IF) by making two signals inverted from each other from the amplified IF signal. (31G) And an analog / digital television tuner.