KR20070080906A - Satellite and terrestrial tuner - Google Patents

Abstract

A tuner for satellite broadcasting and terrestrial broadcasting is provided to simplify the constitution of a circuit, thereby downsizing the tuner and reducing the production cost of the tuner. A high frequency input terminal(30) receives high frequency signals for terrestrial broadcasting and satellite broadcasting. A low noise amplifier(31) amplifies the level intensities of the high frequency signals, and outputs the amplified signals. A tracking filter(32) separates, or doubly expands and separates the bands of the high frequency signals outputted from the low noise amplifier(31). An MOPLL(Mixer Oscillator Phase Locked Loop) IC(33) outputs a middle frequency obtained by mixing the high frequency signals outputted from the tracking filter(32) into a local oscillation frequency or a double local oscillation frequency. A middle frequency filter and amplifier(34) filters, amplifies, and outputs the middle frequency signal outputted from the MOPLL IC(33).

Description

Satellite and terrestrial tuner {SATELLITE AND TERRESTRIAL TUNER}

1 is a block diagram of a conventional satellite and terrestrial tuner

Figure 2 is a block diagram of a conventional satellite and terrestrial tuner

3 is a block diagram of a satellite and terrestrial tuner according to an embodiment of the present invention;

4 is a detailed view of a resonance circuit of a local oscillator according to an embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

30; High frequency input 31; Low noise amplifier

32; Tracking filter 33; MOPEL integrated circuit

34; Intermediate frequency filter and amplifier 35; Demodulator

UHF-MIX; UHF mixer VHF-MIX; VHF Mixer

       SC; Control signal 40; Resonant circuit

The present invention relates to a satellite and terrestrial tuner.

In general, satellite and terrestrial broadcasts use different frequency bands, that is, satellite waves use 950MHZ ~ 2150MHZ, terrestrial waves use VHF band using 90MHZ ~ 220MHZ, and UHF band using 474MHZ ~ 858MHZ. Terrestrial broadcast tuners will not be able to receive satellite broadcasts.

Until now, terrestrial broadcasting is more popular than satellite broadcasting, but when satellite broadcasting and terrestrial broadcasting coexist in the future, a receiver capable of receiving both phase wave broadcasting and terrestrial broadcasting is required.

As a part of this, a satellite and terrestrial tuner capable of receiving and watching both satellite and terrestrial broadcasts with a single receiver has been developed, and the satellite and terrestrial tuner is typically amplified and mixed with a first intermediate frequency signal. It uses a double conversion method that converts the signal to the intermediate medium frequency and detects the difference.

Satellite and terrestrial combined tuner using the double conversion method is, as shown in FIG. 1 registered and registered by the applicant (Application No. 10-2001-17594), the first antenna (ANT1), the second antenna (ANT2), AGC 101, first amplifier 102, first low pass filter 103, first mixer 104, first local oscillator 105, first PLL 106, and band pass filter 107 ), Second amplifier 108, second mixer 109, second local oscillator 110, second PLL 111, third mixer 112, third local oscillator 113, third A PLL 114, a first switch 115 and a second switch 116, and a second low pass filter 117 and a third low pass filter 118 are included.

The conventional satellite and terrestrial tuner configured as described above switches the first switch 115 and the second switch 116 to terrestrial reception in a demodulator (not shown) when the terrestrial broadcast is to be received. After converting the terrestrial signal introduced through ANT1 to the first switch 115 and the first mixer 104 and down-converting the second mixer 109, the second switch 116 and the second The low pass filter 117 outputs an intermediate frequency in the 10 MHz band.

On the other hand, when a satellite wave broadcast is to be received, the demodulator switches the first switch 115 and the second switch 116 to satellite wave reception, and converts the satellite wave broadcast signal introduced through the second antenna ANT2 into the third mixer 112. ), After down-converting through the first switch 115 and the second mixer 109, an intermediate frequency of 10 to 45 MHz band is output through the second switch 116 and the third low pass filter 118. .

In addition, as shown in FIG. 2, which the applicant has filed (Application No. 10-2002-31800), a terrestrial and satellite wave tuner includes a terrestrial antenna 21 and a satellite wave antenna 29, a tracking filter 22, and a reception filter. Terrestrial mixers 23a, 23b, 23c, satellite wave mixers 29a, terrestrial local oscillators 26a, 26b, 26c and satellite waves that mix desired high frequencies and predetermined oscillation frequencies to output desired intermediate frequencies The local oscillator 29c, low pass filters 24a, 24b, 24c, and 29b for acquiring only an audible frequency and received signals separated by frequencies by the tracking filter 22 for a specific frequency band. Terrestrial switches 25a, 25b and 25c for receiving and selecting a received signal, and a terrestrial image rejecting unit which is a terrestrial image rejecting unit 27 and a third filter 50a for removing an image frequency ( 50) and a terrestrial wave selector switch 28 selected by terrestrial or satellite waves. It consists of a satellite wave selection switch 51 and the demodulation Damn, 60.

The tuner configured as described above separates the high-frequency signals of terrestrial 44 MHz to 860 MHz received through the terrestrial antenna 21 into three units of 44 to 120 MHz, 120 to 360 MHz, and 360 to 860 MHz through the tracking filter 22. One of the mixers 23a, 23b, 23c, low pass filters 24a, 24b, 24c, and the terrestrial switches 25a, 25b, 25c may be used for the terrestrial image rejection unit 27, The demodulation IC 60 is output to the demodulation IC 60 through the terrestrial wave selector switch 28.

On the other hand, the high-frequency signal of the satellite wave 950 ~ 2150MHz received through the satellite wave antenna 29 is a satellite wave mixer 29a, satellite low pass filter 29b, satellite image rejection unit 50, satellite wave selection switch 51 Through the demodulation IC 60 is output.

As described above, the conventional satellite and terrestrial tuner both receive the terrestrial and satellite broadcast signals separately through the respective terrestrial and satellite antennas, and also select a desired broadcast signal for the received terrestrial and satellite broadcast signals. The mixer and local oscillator must be used to receive the signal and to separate it using at least two switches.

Therefore, the conventional satellite and terrestrial tuner has a somewhat complicated circuit configuration, and the complicated circuit configuration causes a problem of lowering the reliability of the tuner and increasing the production cost.

It is an object of the present invention to provide a satellite and terrestrial tuner capable of simply receiving a terrestrial broadcast as well as a satellite broadcast.

Another object of the present invention is to provide a satellite and terrestrial tuner that can simplify the circuit configuration and reduce the production cost.

In order to achieve the above object, the present invention includes a high frequency input terminal for receiving a high frequency signal of terrestrial and satellite wave broadcasting;

A low noise amplifier for amplifying and outputting the high frequency signal level of terrestrial and satellite wave signals received at the high frequency input terminal;

A tracking filter for separating or doubling the band of the high frequency signal outputted from the low noise amplifier;

An MOPEL integrated circuit configured to output an intermediate frequency by mixing a high frequency signal output from the tracking filter with a local oscillation frequency or a double local oscillation frequency;

And an intermediate frequency filter and an amplifier for filtering, amplifying and outputting an intermediate frequency signal output from the MOPEL integrated circuit.

Another invention for realizing the above object is a high frequency input stage for receiving a high frequency signal of terrestrial and satellite wave broadcasting;

A low noise amplifier for amplifying and outputting the high frequency signal level of terrestrial and satellite wave signals received at the high frequency input terminal;

A tracking filter for separating or doubling and dividing a band of the high frequency signal output from the low noise amplifier;

An MOPEL integrated circuit for mixing the high frequency signal output from the tracking filter with a local oscillation frequency or twice the local oscillation frequency to output an intermediate frequency;

An intermediate frequency filter and an amplifier for filtering, amplifying, and outputting an intermediate frequency signal output from the MOPEL integrated circuit; and a signal connected to the intermediate frequency filter and the amplifier and input from the intermediate frequency filter and the amplifier. And a demodulator for dividing the satellite wave or the terrestrial signal and outputting a control signal corresponding to the separated state to the tuner.

Therefore, according to the present invention, a tuner that tunes and demodulates a received high frequency signal and outputs a broadcast signal provides twice the tracking extension and oscillation frequency when receiving a satellite broadcast, thereby easily watching satellite and terrestrial broadcasts with a single tuner. It will be possible.

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

3 is a block diagram of a satellite and terrestrial tuner according to an embodiment of the present invention, Figure 4 is a detailed view of the resonant circuit of a local oscillator according to an embodiment of the present invention, a high frequency input terminal 30, a low noise amplifier ( 31), a tracking filter 32, an MOPEL integrated circuit 33, an intermediate frequency filter and an amplifier 34, and further includes a demodulator 35 in the intermediate frequency filter and the amplifier 34.

The high frequency input terminal 30 receives and inputs high frequency signals of satellite and terrestrial broadcasting from an antenna (not shown).

The low noise amplifier 31 is connected to the high frequency input terminal 30, the satellite wave signal of the 950MHZ ~ 2150MHZ band, the VHF high frequency signal of the 90MHZ ~ 220MHZ band, and the UHF high frequency signal of the 474HZ ~ 860MHZ band to the signal field strength As a result, the signal is amplified to a moderate level signal.

The tracking filter 32 is composed of a UHF tracking filter 321 and a VHF tracking filter 322, and the UHF tracking filter 321 is a high frequency signal amplified from the low noise amplifier 31 into a level signal of an appropriate size. The included noise is removed and only high frequency signals corresponding to the desired satellite and UHF frequency bands are separated.

In addition, the UHF tracking filter 321 constitutes a resonant circuit 40 that doubles the oscillation frequency to expand the high frequency tracking of the UHF band by the control signal SC.

As shown in FIG. 4, the resonant circuit 40 is connected in series to a coil L1 to which a varactor VARACTOR is connected by a capacitor C1, a coil L2, and a diode D1 resistor R1. The resonator 41 and the switching means 42 constituted by a transistor Q1 for switching and driving the resonator 41.

The VHF tracking filter 322 removes the noise included in the high frequency signal amplified from the low noise amplifier 31 into a level signal of an appropriate magnitude and separates only the high frequency signal corresponding to the desired VHF frequency band.

The MLP integrated circuit 33 is a module consisting of a mixer (MIX), oscillator (OSC), phase locked loop (PLL) as a single integrated circuit, the UHF MOPEL 331 and VHF MOPEL ( 332).

The UHF MOPEL 331 is a UHF mixer which converts and outputs a satellite wave signal of the 950MHZ ~ 2150MHZ band or UHF signal of the 474MHZ ~ 858MHZ band with a local oscillation frequency and converts the frequency into an intermediate frequency signal. UHF-MIX); An UHF local oscillator (OSC) for outputting a predetermined local oscillation frequency to the UHF mixer (UHF-MIX) according to a control voltage of a phase locked loop; It consists of a phase locked loop (PLL) for controlling the local oscillation frequency by comparing the local oscillation frequency of the UHF local oscillator (OSC) with an arbitrary reference frequency.

The UHF local oscillator OSC forms a resonant circuit 40 to double the local oscillation frequency of the UHF band by the control signal SC.

As shown in FIG. 4, the resonant circuit 40 includes a capacitor C1, a coil L2, and a diode D1 resistor R1 connected in series to a coil L1 to which a varactor VARACTOR is connected. The resonator 41 and the switching means 42 constituted by a transistor Q1 for switching and driving the resonator 41.

The VHF MOPEL 332 is a VHF mixer (VHF-MIX) for mixing the VHF signal of the 90MHZ ~ 220MHZ band selected by the VHF tracking filter 322 with the local oscillation frequency to convert the frequency into an intermediate frequency signal; A VHF local oscillator (OSC) for outputting a predetermined local oscillation frequency according to a control voltage of a phase locked loop to the VHF mixer (VHF-MIX); It consists of a phase locked loop (PLL) for controlling the local oscillation frequency by comparing the local oscillation frequency of the UHF local oscillator (OSC) with an arbitrary reference frequency.

An amplifier (AMP) for amplifying the intermediate frequency signal output from the UHF mixer (UHF-MIX) and the VHF mixer (VHF-MIX) and the UHF mixer (UHF-MIX) and the VHF mixer (VHF-MIX), respectively. Will be connected.

The intermediate frequency filter and the amplifier 34 may be composed of a surface elastic filter (SAW) and an intermediate frequency amplifier (IF AMP) to output an unnecessary frequency included in an intermediate frequency amplified by the MOPEL integrated circuit 33 and output. And compensatively amplifies the reduction in gain generated during the frequency removal.

The demodulator 35 is composed of demodulation integrated circuits of QPSK (Orthogonal Phase Shift Keying) and OFDM (Orthogonal Frequency Division Multiplexing) schemes, and transmits an intermediate frequency output from the intermediate frequency filter and the amplifier 34 to the original transmission. The signal is demodulated and output.

In addition, the demodulator 35 receives the address data signal SDA and the clock signal SCL from an external controller and transmits the control signal SC to the local oscillator OSC of the UHF tracking filter 321 and the UHF MOPEL 331. And an address data signal SDA and a clock signal SCL to the MOPEL integrated circuit 33.

The present invention configured as described above is a high frequency signal of the ground wave 90MHZ ~ 220MHZ VHF band, 474MHZ ~ 858MHZ UHF band, satellite wave 950MHZ ~ 2150MHZ band through the antenna (not shown) All of them are received and output to the low noise amplifier 31.

The low noise amplifier 31 amplifies the received satellite wave signals of the 950MHZ ~ 2150MHZ band, and VHF and UHF high frequency signals of the 90MHZ ~ 220MHZ, 474MHZ ~ 858MHZ band to a level signal of an appropriate magnitude and outputs them to the tracking filter 32. In this case, the tracking filter 32 inputs a corresponding high frequency signal by the UHF tracking filter 321 and the VHF tracking filter 322.

Therefore, the UHF tracking filter 321 inputs only 950MHZ ~ 2150MHZ band satellite wave and 474MHZ ~ 858MHZ band UHF high frequency signal, and the VHF tracking filter 322 inputs only 90MHZ ~ 220MHZ band VHF high frequency signal, In this case, the UHF tracking filter 321 and the VHF tracking filter 322 remove noise from the input high frequency signal and separate only each VHF, UHF, and satellite wave high frequency signal corresponding to a desired frequency band. Will print).

The MOPEL integrated circuit 33 inputs high frequency signals separated and output from the UHF tracking filter 321 and the VHF tracking filter 322 through the UHF MOPEL 331 and the VHF MOPEL 332. The input high frequency signals are UHF MOPEL 331 and VHF MOPEL 332 by the address data signal SDA, the clock signal SCL, and the control signal SC output from the demodulator 35. Will print).

At this time, the demodulator 35 scans the MLPEL integrated circuit 33 under the assumption that a satellite wave broadcast signal is input to the initially received high frequency signal.

Subsequently, the terrestrial signal and the satellite signal are separated from the high frequency signal received by the demodulator 35 to receive the terrestrial signal and the satellite signal while outputting the address data signal SDA, the clock signal SCL, and the control signal SC. .

Therefore, when receiving terrestrial broadcasting, the demodulator 35 controls the address data signal SDA, the clock signal SCL, and the control to the UHF MOPEL 331 and the VHF MOPEL 332 of the MOPEL integrated circuit 33. In addition to outputting the signal SC, the control signal SC is outputted to the UHF tracking filter 321 of the tracking filter 32. In this case, the control signal SC outputs a high signal and is shown in FIG. As described above, the UHF MOPEL 331 of the MOPEL integrated circuit 33 and the resonant circuit 40 provided in the UHF tracking filter 321 of the tracking filter 32 do not allow double resonance.

Therefore, in the UHF MOPEL 331 and the VHF MOPEL 332 of the MOPEL integrated circuit 33, 474 to 858 MHz of the UHF band separated from the UHF tracking filter 321 and the VHF tracking filter 322. A high frequency signal and a 90MHZ to 220MHZ high frequency signal of the VHF band are respectively input.

In the UHF MOPEL 331, the oscillation frequency is controlled by the control voltage received from 474 to 858 MHz of the UHF band input from the UHF tracking filter 321 through the UHF mixer (UHF-MIX) and the phase locked loop (PLL). The local oscillation frequency output from the generated UHF local oscillator (OSC) is mixed to output the desired intermediate frequency.

The intermediate frequency output from the UHF mixer (UHF-MIX) is amplified by an amplifier (AMP) and output to the intermediate frequency filter and the amplifier 34. The intermediate frequency filter and the amplifier 34 have the surface elastic filter ( SAW), removes unnecessary frequencies included in the intermediate frequency signal through the IF AMP, compensates for the reduction of the gain value generated during the frequency elimination, and amplifies the original transmission signal through the demodulator 35. By demodulating with, the desired UHF broadcast is watched.

In the VHF MOPEL 332, an oscillation frequency is generated by a control voltage received from 90 to 220 MHz of a VHF band input from the VHF tracking filter 321 through a VHF mixer (VHF-MIX) and a phase locked loop (PLL). By mixing the local oscillation frequency output from the VHF local oscillator (OSC) to generate a desired intermediate frequency.

The intermediate frequency output from the VHF mixer (VHF-MIX) is amplified by an amplifier (AMP) and output to the intermediate frequency filter and the amplifier 34. The intermediate frequency filter and the amplifier 34 have the surface elastic filter ( SAW), removes unnecessary frequencies included in the intermediate frequency signal through the IF AMP, compensates for the reduction of the gain value generated during the frequency elimination, and amplifies the original transmission signal through the demodulator 35. By demodulating with, the desired VHF broadcast is watched.

On the other hand, when receiving a satellite wave broadcast, the satellite wave high frequency signal receives 950MHZ ~ 1716MHZ, which is twice the terrestrial UHF high frequency signal 474MHZ ~ 858MHZ, it is impossible to receive by the terrestrial tuner, but the UHF tracking of the tracking filter 32 Since the resonant circuit 40 outputting the oscillation frequency twice in the local oscillator OSC of the filter 321 and the UHF MOPEL 331 is configured, the demodulator 35 includes the UHF tracking filter 321. And control signals SC to the local oscillator OSC of the UHF MOPEL 331, respectively.

Therefore, in the UHF tracking filter 321, the resonant circuit 40 is resonated twice by the control signal SC of the demodulator 35. That is, the switching of the resonant circuit 40 from the demodulator 35 is performed. The low signal is applied to the transistor Q1, which is means 42, and the transistor Q1 is turned off so that the driving voltage 5V is applied to the resonator 41. Thus, the resonator 41 generates a resonance frequency. This resonant frequency is combined with the resonant frequency of the varactor and coil L1 to generate twice the resonant frequency.

Therefore, the UHF tracking filter 321 secures the tracking band to 950MHZ to 1716MHZ, which doubles the tracking of the 474MHZ to 858MHZ UHF band, and filters the phase wave 950MHZ to 2150MHZ band input from the low noise amplifier 31. The filtered satellite wave signal is input to the UHF mixer (UHF-MIX) of the UHF MOPEL 331 of the MOPEL integrated circuit 33.

Therefore, the UHF mixer (UHF-MIX) of the UHF MOPEL 331 also generates a local oscillation frequency according to the control voltage of the phase locked loop (PLL) by the control signal (SC) received from the demodulator (35). The resonance circuit 40 as shown in FIG. 4 included in the OSC generates twice the resonance frequency while driving, that is, the switching means 42 of the resonance circuit 40 from the demodulator 35. Since a low signal is applied to the in transistor Q1 and the transistor Q1 is turned off, the driving voltage 5V is applied to the resonator 41 to generate a resonance frequency. The resonance frequency is a varactor and a coil ( Since it is synthesized with the resonance frequency by L1), the oscillation frequency is doubled.

Therefore, in the UHF mixer (UHF-MIX), the local oscillation frequency generated twice and the satellite wave high frequency signal input from the UHF tracking filter 321 are mixed to output a desired intermediate frequency, and the output intermediate frequency is an amplifier (AMP). After being amplified through), it is output to the intermediate frequency filter and the amplifier 34.

The intermediate frequency filter and the amplifier 34 are included in the intermediate frequency signal through the surface elastic filter (SAW) and the intermediate frequency amplifier (IF AMP) with respect to the intermediate frequency signal output from the MOPEL integrated circuit 33. By eliminating unnecessary frequencies and compensating amplification of the gain value generated during the frequency elimination, demodulating the original transmission signal through the demodulator 35, the desired satellite wave broadcasting can be viewed.

As described above, in the present invention, a tuner that tunes and demodulates a broadcast high frequency signal received by an antenna and outputs a broadcast signal to a tuner that receives a satellite wave band in order to receive a satellite wave signal when receiving satellite broadcasts. By providing the frequency, it is possible to simply receive the satellite wave broadcast, and the simple circuit configuration can reduce the production cost and provide the effect of miniaturization.

Claims (19)

A high frequency input terminal for receiving high frequency signals of terrestrial and satellite wave broadcasting; A low noise amplifier for amplifying and outputting the high frequency signal level of terrestrial and satellite wave signals received at the high frequency input terminal; A tracking filter for separating or doubling the band of the high frequency signal outputted from the low noise amplifier; An MOPEL integrated circuit configured to output an intermediate frequency by mixing a high frequency signal output from the tracking filter with a local oscillation frequency or a double local oscillation frequency; Combined satellite and terrestrial tuner including an intermediate frequency filter and an amplifier for filtering, amplifying and outputting the intermediate frequency signal output from the MOPEL integrated circuit. 2. The satellite and terrestrial tuner of claim 1, wherein the tracking filter comprises two filters separating the UHF band and the VHF band. 2. The satellite and terrestrial tuner of claim 1, wherein the tracking filter includes a resonant circuit that doubles the oscillation frequency of the UHF band. 4. The satellite and terrestrial tuner of claim 3, wherein the resonant circuit comprises a resonator in which a capacitor, a coil, a diode, and a resistor are connected in series to a coil to which the varactor is connected. 4. The satellite and terrestrial tuner of claim 3, wherein the resonant circuit further comprises switching means for switching and driving the resonator. 6. The satellite and terrestrial tuner as claimed in claim 5, wherein the switching means is composed of a transistor. 4. The satellite and terrestrial tuner as claimed in claim 3, wherein the resonant circuit is connected to a demodulator and resonantly driven by a control signal of the demodulator. 2. The satellite and terrestrial tuner of claim 1, wherein the MOPEL integrated circuit comprises a UHF band MOPEL and a VHF band MOPEL. 2. The satellite and terrestrial tuner of claim 1, wherein the MOPEL integrated circuit includes a resonant circuit that doubles the oscillation frequency of the UHF band MOPEL. 10. The satellite and terrestrial tuner of claim 9, wherein the resonant circuit comprises a resonator in which a capacitor, a coil, a diode, and a resistor are connected in series to a coil to which the varactor is connected. 10. The satellite and terrestrial tuner of claim 9, wherein the resonant circuit further comprises switching means. 12. The satellite and terrestrial tuner as set forth in claim 11, wherein said switching means comprises a transistor. 10. The satellite and terrestrial tuner of claim 9, wherein the resonant circuit is connected to the demodulator and resonates by a control signal of the demodulator. 2. The satellite and terrestrial tuner of claim 1, wherein the MOPEL integrated circuit further comprises an amplifier. A high frequency input terminal for receiving high frequency signals of terrestrial and satellite wave broadcasting; A low noise amplifier for amplifying and outputting the high frequency signal level of terrestrial and satellite wave signals received at the high frequency input terminal; A tracking filter for separating or doubling and dividing a band of the high frequency signal output from the low noise amplifier; An MOPEL integrated circuit for mixing the high frequency signal output from the tracking filter with a local oscillation frequency or twice the local oscillation frequency to output an intermediate frequency; And an intermediate frequency filter and an amplifier for filtering, amplifying and outputting an intermediate frequency signal output from the MOPEL integrated circuit, and receiving a signal input from the intermediate frequency filter and the amplifier connected to the intermediate frequency filter and the amplifier. And a demodulator for separating a satellite wave or terrestrial signal and outputting a control signal corresponding to the separated state to a tuner. 16. The satellite and terrestrial tuner of claim 15, wherein the demodulator distinguishes the satellite wave signal from the terrestrial wave signal while initially scanning the received intermediate frequency signal as a satellite wave signal. 16. The satellite and terrestrial tuner of claim 15, wherein the demodulator outputs a control signal which generates twice the oscillation frequency upon reception of the satellite wave broadcast. 16. The satellite and terrestrial tuner of claim 15, wherein the demodulator outputs a control signal to the tracking filter and MOPEL. 16. The satellite and terrestrial tuner of claim 15, wherein the demodulator outputs a control signal for generating a double oscillation frequency to the UHF tracking filter and the UHF MOPEL.

Images