KR20110035816A - Receiving apparatus, antenna switching circuit of receiving apparatus, and tuner module of receiving apparatus - Google Patents

Abstract

PURPOSE: An antenna changing circuit and a tuner module of a receiving apparatus are provided to simplify the structure of the antenna changing circuit. CONSTITUTION: A tuner module of a receiving apparatus comprises a first antenna(1) receiving a television broadcasting, a diode switch for outputting the receiving signal by selecting the broadcasting signals from the first antenna or a second antenna(2), a first power supplying unit(11) for supplying operating power to an LNA(3) of the second antenna, a second power supply unit(9) for supplying low direct voltage to the diode, and a frequency conversion unit(51) for converting a receiving signal into a specific frequency band.

Description

RECEIVING APPARATUS, ANTENNA SWITCHING CIRCUIT OF RECEIVING APPARATUS, AND TUNER MODULE OF RECEIVING APPARATUS}

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a receiving device, an antenna switching circuit of a receiving device, and a tuner module of a receiving device, and more particularly, to a receiving device with a simplified antenna switching unit, an antenna switching circuit of a receiving device, and a tuner module of a receiving device.

In PND (Personal Navigation Device) and Portable TV (Television), terrestrial digital broadcasts are often received while mounted in a car. Therefore, it is important not only to enlarge the reception area but also to have a good reception sensitivity. Background Art [0002] Some mobile devices such as cellular phones receive one-segment broadcast, which is a type of terrestrial digital broadcast, using a ceramic chip antenna embedded in the device or a rod antenna attached to the device. On the other hand, in the above-described PND and portable TV, for example, a film antenna (many formed by embedding a conductor such as copper in a flexible substrate) or a rod antenna attached to the apparatus, for example, an LNA attached to a vehicle body. (Low Noise Amplifier) It is often used to connect the built-in external antenna. By using an external antenna, the above-mentioned improvement of reception sensitivity can be expected significantly. On the other hand, an antenna switching circuit for switching the received signal supplied to the receiving circuit and its switching control are required.

Patent document 1 relates to an antenna switching circuit. When the reception state is a strong electric field state, the power supply to the antenna switching circuit is turned off, and signal output is obtained by isolating between boards. A technique for suppressing deterioration and distortion of the circuit and ensuring a good reception state is disclosed.

[Patent Document 1] Japanese Patent Application Laid-Open No. 2000-341185

In the reception circuit of the PND or portable TV, as described above, an antenna switching circuit for selecting which antenna the received signal is supplied to the reception circuit, and its switching control are necessary. For this reason, an IC (Integrated Circuit) for switching is mounted between the antenna and the tuner module at the head of the receiving circuit, and antenna switching is performed by a control signal from an MPU (Micro Processor Unit). In addition, the power of the LNA included in the external antenna is supplied from the receiver side.

However, the antenna for switching the antenna needs to incorporate a switch of a large MOSFET (Metal Oxide Semiconductor Field Effect Transistor), which has a problem that it is large and expensive. In addition, a control signal for switching control of this switch is sometimes required, which is undesirable for miniaturizing and simplifying the apparatus.

SUMMARY OF THE INVENTION An object of the present invention is to solve these problems and to provide a receiver that simplifies the antenna switch, an antenna switch circuit of the receiver, and a tuner module of the receiver.

In order to achieve the above object, the present invention is a tuner module of a television broadcast receiving apparatus which receives a broadcast signal transmitted by predetermined modulation and processes a received signal, and is supplied from a first antenna that receives the television broadcast. A diode switch for selecting any one of the received signal and a received signal supplied from a second antenna for receiving the television broadcast and amplifying the LNA incorporating the received signal, and outputting a received signal; A supply terminal of a first power supply for supplying a voltage to control ON / OFF operation and supplying operation power to an LNA built in the second antenna, and a lower than a DC voltage supplied by the first power supply to the diode switch. A supply terminal of a second power supply for supplying a DC voltage to the diode; and a cathode side of the diode switch And a demodulator for demodulating the modulation carried out at the time of transmission. have.

In addition, the present invention provides a television broadcast receiving apparatus which receives a broadcast signal which is data compressed based on an MPEG scheme, subjected to predetermined modulation, and processes a received signal, comprising: a first antenna for receiving the television broadcast; And an input terminal through which a received signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA containing a received signal is input, and a received signal supplied from the first antenna, supplied from the input terminal to an anode terminal. A diode having a received signal connected to a cathode terminal, a first power supply supplying a direct current voltage to the cathode terminal of the diode, and supplying operation power to an LNA built in the second antenna, and an anode terminal of the diode. A second power supply configured to supply a DC voltage lower than a DC voltage supplied by the first power supply to the cathode terminal; A control unit for turning on / off the first power supply, a reception signal displayed on the cathode side of the diode, a frequency conversion unit for frequency conversion of the first power supply to a predetermined frequency, and a reception signal converted in the frequency conversion unit is supplied. A demodulation section for demodulating the modulation carried out at the time of transmission, a received signal demodulated at the demodulation section, and an MPEG decoder for decompressing and decoding data compression based on the MPEG system at the time of transmission; A received signal decoded by the MPEG decoding unit, having an AV-IF unit for converting into an analog signal having a format suitable for displaying an image, and a monitor for displaying the received signal converted by the AV-IF unit. It features.

In addition, the present invention is an antenna switching circuit of a receiving apparatus for a television broadcast that receives a broadcast signal and processes the received signal, wherein the received signal supplied from the first antenna for receiving the television broadcast is connected to an anode terminal for the television broadcast. The received signal supplied from the second antenna, which is received and amplified by the LNA incorporating the received signal, is supplied to the diode connected to the cathode terminal, and the direct current voltage is supplied to the cathode terminal of the diode, and the LNA embedded in the second antenna is provided. A first power supply for supplying operating power, a second power supply supplying a direct current voltage lower than a direct current voltage supplied by the first power supply to the cathode terminal to an anode terminal of the diode, and the first power supply on / off control And a control unit configured to switch the received signal displayed on the cathode side of the diode to produce an output. And there.

In addition, the present invention is a tuner module of a television broadcast receiving apparatus that receives a broadcast signal transmitted by predetermined modulation and processes the received signal, wherein the received signal received by the first antenna receiving the television broadcast is A first input terminal to be input, a second input terminal to which a received signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal is input, and a received signal supplied from the first input terminal Supplies a direct current voltage to the anode terminal, a diode to which the received signal supplied from the second input terminal is connected to the cathode terminal, a direct current voltage to the cathode terminal of the diode, and supplies operating power to the LNA embedded in the second antenna. DC voltage supplied by the first power supply to the cathode terminal and the anode terminal of the diode A supply terminal of the second power supply for supplying a lower DC voltage, a reception signal shown on the cathode side of the diode is supplied, and a frequency conversion section for frequency converting it to a predetermined frequency; and a reception signal converted in the frequency conversion section. Is supplied, and has a demodulation section for demodulating the modulation carried out at the time of transmission.

In addition, the present invention provides a television broadcast receiving apparatus which receives a broadcast signal which is data compressed based on an MPEG scheme, subjected to predetermined modulation, and processes a received signal, comprising: a first antenna for receiving the television broadcast; A first diode to which a received signal received by a second antenna that receives the television broadcast and is amplified by an LNA incorporating the received signal is input, and a first diode to which a received signal supplied from the first antenna is connected to an anode terminal; Supplying a DC voltage to a second diode having a received signal supplied from the input terminal connected to an anode terminal, a cathode terminal connected to a cathode terminal of the first diode, and an anode terminal of the second diode; A first power supply for supplying operation power to an LNA embedded in the second antenna, and the first terminal at an anode terminal of the first diode; A second power supply for supplying a DC voltage lower than a DC voltage supplied by the power supply to the anode terminal of the second diode, a control unit for ON / OFF control of the first power supply, and a cathode side of the first and second diodes. A demodulation section for demodulating the modulation carried out at the time of transmission, supplied with a frequency converting section for supplying the received received signal and frequency converting it to a predetermined frequency, and receiving a signal converted in the frequency converting section; A MPEG decoder that is supplied with a demodulated signal at < RTI ID = 0.0 >, < / RTI > And an AV-IF unit for converting to an analog signal in a format, and a monitor for displaying an image of the received signal converted in the AV-IF unit.

Moreover, this invention is an antenna switching circuit of the receiver of the television broadcast which receives a broadcast signal and processes the received signal, The 1st diode in which the received signal supplied from the 1st antenna which receives the said television broadcast was connected to the anode terminal. A second diode connected to an anode terminal of a received signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal, and a cathode terminal of which is connected to a cathode terminal of the first diode; A first power supply for supplying a DC voltage to the anode terminal of the second diode and supplying operating power to an LNA embedded in the second antenna; and the first power supply to the anode terminal of the first diode; ON / OFF control of the 2nd power supply which supplies the DC voltage lower than the DC voltage supplied to the anode terminal of a diode, and the said 1st power supply. And a control unit configured to switch the received signal shown on the cathode side of the first and second diodes to produce an output.

In addition, the present invention is a tuner module of a television broadcast receiving apparatus that receives a broadcast signal transmitted by predetermined modulation and processes the received signal, wherein the received signal received by the first antenna receiving the television broadcast is A first input terminal to be input, a second input terminal to which a received signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal is input, and a received signal supplied from the first input terminal A first diode having a first diode connected to an anode terminal, a second diode connected with a receive signal supplied from the second input terminal, a cathode terminal connected to a cathode terminal of the first diode, and the second diode Supply terminal of the first power supply for supplying a DC voltage to the anode terminal of the supply, and supplying operating power to the LNA built in the second antenna And a supply terminal for a second power supply for supplying a direct current voltage lower than a direct current voltage supplied by the first power supply to the anode terminal of the second diode to the anode terminal of the first diode, and the first and second diodes. The reception signal shown on the cathode side is supplied, and a frequency conversion section for frequency converting it to a predetermined frequency and a reception signal converted at the frequency conversion section are supplied to demodulate the demodulation performed at the time of transmission. It features.

According to the present invention, it is possible to provide a receiving device which simplifies the antenna switching unit, an antenna switching circuit of the receiving device, and a tuner module of the receiving device, which can contribute to the miniaturization of the device and the improvement of its convenience. have.

1 is a block diagram of a broadcast receiver of a conventional receiver.
2 is a block diagram of a broadcast receiver of a receiver according to an embodiment of the present invention.
3 is another block diagram of a broadcast receiver of a receiver according to an embodiment of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described using drawing.

1 is a block diagram of a broadcast receiver of a conventional receiver, and FIG. 2 is a block diagram of a broadcast receiver of a receiver according to an embodiment of the present invention. First, after explaining an example of a prior art, this Example is demonstrated in detail.

In Fig. 1, reference numeral 1 denotes a film antenna embedded in a receiver or a rod antenna attached to a receiver, and reference numeral 2 denotes an external antenna of LNA built in a mobile body (such as a vehicle body of a vehicle) on which the receiver is mounted. . The external antenna 2 often protrudes out of the vehicle body. Reference numeral 1A denotes an input terminal of the received signal received by the antenna 1, and reference numeral 2A denotes an input terminal of the received signal received by the antenna 2. Since the antenna 2 is located away from the broadcast receiver as described above, the broadcast receiver has an input terminal 2A for connection thereto. On the other hand, since the antenna 1 is integrated with the broadcast receiving unit, the input terminal 1A does not have to be particularly conscious as a component.

The received signal received by the antenna 1 is supplied to the input terminal of the antenna switching IC 4 via the capacitor C1. The received signal received by the antenna 2 is amplified by the LNA 3 to a predetermined level suitable for signal processing in a later circuit, and then supplied to the other input terminal of the antenna switching IC 4 via the capacitor C2. do.

The LNA 3 requires an operating power supply, but the DC power generated by the first power supply 11 (which often includes an IC) is supplied to the LNA 3 through the coil L1 after being smoothed at the capacitor C4. It is becoming. In the drawing, the output line of the LNA 3 supplies the reception signal to the antenna switching IC 4 as described above, but the DC power supply is often supplied to the LNA 3 in such a manner as to overlap the signal line. In addition, the coil L1 and the capacitor C4 supply the above-described DC power, and also have an effect of setting the input impedance viewed from the LNA 3 side to a predetermined value.

The MPU (Micro Processor Unit) 12 is a control unit that controls at least the entire broadcast receiving unit of the receiving device. The MPU 12 sends an LNA power supply switching control signal for controlling whether to supply power to the first power source 11 to perform ON / OFF control of the first power source 11. The control terminal of the antenna switching IC 4 is also sent an antenna switching control signal for controlling which of the antennas 1 and 2 to select a reception signal to select the reception signal. When the antenna switching control signal selects the reception signal received by the external antenna 2, the LNA power supply switching signal controls the first power source 11 to be turned on. On the contrary, when the former selects the reception signal received by the antenna 1, the latter controls the first power source 11 to be turned off.

The received signal selected by the antenna switching IC 4 based on the antenna switching signal is supplied to the tuner module 5 via the capacitor C3, and signal processing as described later is performed. The coil L2 and the capacitor C5 in the input section of the tuner module 5 form a filter circuit and limit the band of the received signal input to the frequency converter 51.

The antenna switching IC 4 includes a large MOSFET with a small ON resistance. Since the size of the component is large, the occupied area on the substrate is large, so that it is easy to become expensive in terms of cost, and as described above, the antenna switching control There was a problem such as a need for a signal.

EMBODIMENT OF THE INVENTION The 1st Embodiment of this invention which solved these is demonstrated in detail based on FIG.

2 differs greatly from FIG. 1 in that the antenna switching IC 4 is not used, and instead, the diode D1 is provided. In addition, the antenna switching control signal generated by the MPU 12 is It is unnecessary.

In addition, since large components such as the antenna switching IC 4 and the capacitor C2 become unnecessary, the tuner module 5 includes peripheral components including the capacitor C3, C4, the coil L1 and the resistor R1 as well as the diode D1 as shown. It may be mounted on the. Of course, the capacitor C1 may also be mounted in the tuner module 5. As a result, the characteristics of the tuner module 5 alone can be similar to those of the tuner module 5 when mounted inside the receiving apparatus, thereby contributing to shortening the development process.

In addition, in the tuner module 5 as shown, unlike the case of FIG. 1, the input terminals 1A and 1B have a meaning as a component which becomes a cross section.

Next, the whole operation | movement is demonstrated based on the circuit block diagram of FIG. Here, the same reference numerals are given to those which may be the same as the components shown in FIG. 1. In addition, although the capacitance C1, C3, C4, C5, coil L1, L2 etc. attach | subject the same code | symbol to what has a corresponding function, this does not necessarily mean that a value corresponds. For example, in FIG. 1, a filter for limiting the band of the received signal input to the frequency converter 51 by the coil L2 and the capacitor C5 is formed. In FIG. 2, the coils L1 and L2, the capacitor C3, Since values corresponding to C4 and C5 are formed, each value itself is often different.

When the external antenna 2 is not connected to the apparatus as the reception antenna, and only the film antenna or the rod antenna 1 functions, the MPU 12 sends an LNA power supply switching control signal to the first power source 11, The first power source 11 is turned off. That is, no power is supplied to the LNA 3. On the other hand, the positive potential from the second power supply 9 is supplied to the anode side of the diode D1 via the resistor R2. For this reason, the diode D1 becomes forward bias, and the bias current which flows through the resistor R2, the diode D1, the coil L1, and the resistor R1 flows from the 2nd power supply 9. This means that the diode D1 is in the switched-on state, and the received signal received by the antenna 1 is supplied to the frequency converter 51 via the capacitor C1, the diode D1, the capacitors C3 and C5.

On the other hand, when the external antenna 2 is connected to the apparatus, the MPU 12 sends an LNA power supply switching control signal to the first power source 11 to turn on the first power source 11. That is, power is supplied to the LNA 3 via the coil L1 and the receiving signal line. As a result, the received signal received by the external antenna 2 and amplified to the predetermined level by the LNA 3 appears on the cathode side of the diode D1. If the power supply voltage of the first power supply 11 is set higher than the power supply voltage of the second power supply 9 (generally, this condition is satisfied because the former is about 3V and the latter is about 5 to 8V). D1 is turned OFF, and the received signal received by the external antenna 2 is supplied to the frequency converter 51 via the capacitors C3 and C5, while the received signal received by the antenna 1 is diode D1. Is stopped by

In other words, it can be seen that by using the diode D1, not only the miniaturization and simplification of the element for antenna switching but also the antenna switching control signal of FIG. 1 are unnecessary. This is because the magnitude relationship between the voltage values output by the first power source 11 and the second power source 9 also serves as the antenna switching control signal of FIG. 1. In particular, the second power source 9 relates to the supply of operating power to the LNA 3 and to this antenna switching operation.

When the external antenna 2 is connected, the received signal may be used by this. Naturally, the antenna 2 attached to the vehicle body has a better reception state than the antenna 1 attached to the receiver.

In contrast, when determining which antenna the received signal is to be used, it may be set manually. It is also possible to automatically detect whether or not the external antenna 2 is connected and to select it when connected. Several methods are conceivable for automatic detection. The switch component for a detection may exist in the circuit board of a receiver, and when the 1st power supply 11 is turned ON, it may detect whether the predetermined load current flows.

As described above, the received signal selected by the action of the diode D1 is supplied to the frequency converter 51. The frequency converter 51 converts the received high frequency received signal into a frequency band suitable for performing a demodulation operation by the next OFDM demodulator 52. Originally, heterodyne conversion for converting to an intermediate frequency band has been widely used, but in recent years, a direct conversion for converting directly to a baseband band has been increasingly used.

The received signal frequency-converted by the frequency converter 51 is supplied to the OFDM demodulator 52. In terrestrial digital broadcasting, orthogonal frequency division multiplex (OFDM) modulation is performed at the time of transmission from a broadcasting station. The modulation is demodulated by the OFDM demodulator 52, and the received data is demodulated. This data is subjected to MPEG (Moving Picture Experts Group) compression encoding for compressing the capacity of data to be transmitted and received. Therefore, the compressed data demodulated by the OFDM demodulator 52 is supplied to the MPEG decoder 6 to return the data before MPEG compression.

The data decoded by the MPEG decoder 6 is supplied to an AV-IF (Audio Video Interface) unit 7 to form an analog signal of a format suitable for displaying an image on the LCD monitor 8, and furthermore, the LCD ( Liquid Crystal Display) supplied to the monitor 8, and the image display unit displays the broadcasted image for the viewer. The display portion of the monitor 8 is not limited to the LCD, and may be anything, such as a plasma display panel (PDP), an electronic luminescence display (ELD), or a cathode ray tube.

The previous second power source 9 is generated by receiving a built-in battery or a power source 10 supplied from the outside and regulating it. This is also used as a power source for each component including the tuner module 5, the MPEG demodulator 6, and the AV-IF 7. In addition to generating the above LNA power supply switching control signal, the MPU 12 generates a tuner control signal for controlling a channel to be tuned to the tuner module 5, and furthermore, the MPEG decoder 6, AV- The operations of the IF 7, the LCD monitor 8, and the second power source 9 are controlled, that is, at least the entire broadcast receiver of the receiver is controlled.

The first power source 11 may also be generated by regulating the power source 10. In the tuner module 5, the first power source 11 and the second power source 9 are often external components. In this case, the illustrated input terminals 5A and 5B have the meaning of a component as a supply terminal for a power source.

As described above, according to the present embodiment, miniaturization and simplified components are applied to the antenna switch unit, thereby eliminating the antenna switching control signal and reducing the occupied area on the substrate of the component, thereby miniaturizing the device and reducing the cost. Can be achieved.

Next, an embodiment of the present invention will be described based on the circuit block diagram of FIG. 3. 3 is a block diagram different from that of FIG. 2 of the broadcast receiving unit of the receiving apparatus according to the embodiment of the present invention.

FIG. 3 compares the case where the diode D2 is provided between one end of the coil L1 and one end of the capacitor C3, and the diode D1 and the cathode side are connected in common, and the ON currents of the diodes D1 and D2 are passed. The point at which the resistance is set to R3 in FIG. 3 instead of R1 in FIG. 2 is different. Also in this case, similarly to FIG. 2, the first power source 11 is ON / OFF controlled in accordance with the LNA power supply switching control signal from the MPU 12.

When the first power source 11 is ON, the LNA 3 is supplied with operating power from the first power source 11, the diode D2 is turned ON, and the diode D1 is turned OFF, thereby receiving the signal received by the external antenna 2. The received signal is supplied to the frequency converter 51. On the contrary, when the first power source 11 is OFF, the operating power is not supplied to the LNA 3, and the diode D1 is turned on and the diode D2 is turned off, so that the received signal received by the antenna 1 is converted into a frequency converter ( 51).

In addition, in Fig. 3, when the diode D1 is turned on and the received signal received by the antenna 1 is supplied to the frequency converter 51, the circuit part after the cathode side is operated from the diode D2 in the OFF state. The impedance of the long circumferential portion between the outer side of the tuner module 5 and the LNA 3 is hard to be seen. For this reason, there exists a function which reduces the problem that the frequency characteristic at the time of using the antenna 1 changes by the influence of this circumference part. That is, even when the distance between the receiving device and the external antenna 2 is changed and the pattern winding on the circuit board is changed, there is an effect of not causing a large change in characteristics. In general, since the distance between the receiving device and the external antenna 2 and the state of the circumference of the cable vary greatly depending on the use situation and the difference in mounting, this is one of the characteristic effects of the present embodiment.

The above embodiment is an example to the last, and this invention is not limited to this. For example, many other examples can be considered for components incorporated into the tuner module 5. Moreover, although embodiment was described and described in the receiver of TV broadcast, there exist many components other than a mobile communication part other than this. In addition to this, many other embodiments are contemplated, but all are within the scope of the present invention.

1: antenna
2: external antenna
2A: input terminal
3: LNA
5: tuner module
6: MPEG decoder
7: AV-IF part
8: monitor
9: second power source
11: first power source

Claims (9)

A tuner module of a television broadcast receiving apparatus for receiving a broadcast signal transmitted by predetermined modulation and processing a received signal,
Selecting one of a reception signal supplied from a first antenna for receiving the television broadcast and a reception signal supplied from a second antenna for amplifying in the LNA receiving the television broadcast and embedding the reception signal to output a reception signal; Diode switch,
A supply terminal of a first power supply for supplying a predetermined DC voltage to the diode switch to control ON / OFF operation and supplying operation power to an LNA built in the second antenna;
A supply terminal of a second power supply for supplying the diode with a DC voltage lower than a DC voltage supplied by the first power supply to the diode switch;
A frequency converter which is supplied with the received signal shown on the cathode side of the diode switch and frequency-converts it to a predetermined frequency;
A demodulator for supplying a received signal converted by the frequency converter to demodulate the modulation carried out at the time of transmission
Tuner module of a receiving device, characterized in that it has a. A television broadcast receiving apparatus which receives a broadcast signal transmitted by data compression, predetermined modulation is performed on the basis of the MPEG system, and processes the received signal.
A first antenna for receiving the television broadcast,
An input terminal to which a received signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal is input;
A diode in which a received signal supplied from the first antenna is connected to an anode terminal, and a received signal supplied from the input terminal is connected to a cathode terminal;
A first power supply for supplying a DC voltage to the cathode terminal of the diode and supplying operating power to an LNA built in the second antenna;
A second power supply configured to supply a DC voltage lower than a DC voltage supplied by the first power supply to the cathode terminal to an anode terminal of the diode;
A control unit which controls ON / OFF of the first power source;
A frequency converter which is supplied with the received signal shown on the cathode side of the diode, and frequency-converts it to a predetermined frequency;
A demodulator for supplying a received signal converted by the frequency converter to demodulate the modulation carried out at the time of transmission;
An MPEG decoder which is supplied with a received signal demodulated by the demodulator and expands and decodes the data compression based on the MPEG system implemented at the time of transmission;
An AV-IF unit which is supplied with a received signal decoded by the MPEG decoder and converts it into an analog signal having a format suitable for displaying an image;
A monitor for displaying the received signal converted by the AV-IF unit
Receiving device having a. An antenna switching circuit of a television broadcast receiving apparatus that receives a broadcast signal and processes a received signal,
A reception signal supplied from a first antenna for receiving the television broadcast to an anode terminal, and a reception signal supplied from a second antenna for amplifying in the LNA that receives the television broadcast and embeds the reception signal, and a diode connected to the cathode terminal; ,
A first power supply for supplying a DC voltage to the cathode terminal of the diode and supplying operating power to an LNA built in the second antenna;
A second power supply configured to supply a DC voltage lower than a DC voltage supplied by the first power supply to the cathode terminal to an anode terminal of the diode;
Control unit for turning on / off the first power source
And an output signal by switching the received signal shown on the cathode side of the diode to an output. A tuner module of a television broadcast receiving apparatus for receiving a broadcast signal transmitted by predetermined modulation and processing a received signal,
A first input terminal to which a received signal received by a first antenna for receiving the television broadcast is input;
A second input terminal to which a received signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal is input;
A diode in which a received signal supplied from the first input terminal is connected to an anode terminal, and a received signal supplied from the second input terminal is connected to a cathode terminal;
A supply terminal of a first power supply for supplying a DC voltage to the cathode terminal of the diode and supplying operating power to an LNA built in the second antenna;
A supply terminal of a second power supply for supplying a direct current voltage lower than a direct current voltage supplied by the first power supply to the cathode terminal to an anode terminal of the diode;
A frequency converter which is supplied with the received signal shown on the cathode side of the diode, and frequency-converts it to a predetermined frequency;
A demodulator for supplying a received signal converted by the frequency converter to demodulate the modulation carried out at the time of transmission
Tuner module of a receiving device, characterized in that it has a. A television broadcast receiving apparatus which receives a broadcast signal transmitted by data compression, predetermined modulation is performed on the basis of the MPEG system, and processes the received signal.
A first antenna for receiving the television broadcast,
An input terminal to which a received signal received by a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal is input;
A first diode having a received signal supplied from the first antenna connected to an anode terminal;
A second diode having a received signal supplied from the input terminal connected to an anode terminal, and a cathode terminal connected to a cathode terminal of the first diode;
A first power supply for supplying a DC voltage to an anode terminal of the second diode and supplying operating power to an LNA built in the second antenna;
A second power supply configured to supply a DC voltage lower than a DC voltage supplied by the first power supply to the anode terminal of the second diode to an anode terminal of the first diode;
A control unit which controls ON / OFF of the first power source;
A frequency converter which is supplied with the received signal shown on the cathode side of the first and second diodes, and frequency-converts it to a predetermined frequency;
A demodulator for supplying a received signal converted by the frequency converter to demodulate the modulation carried out at the time of transmission;
An MPEG decoder which is supplied with a received signal demodulated by the demodulator and expands and decodes the data compression based on the MPEG system implemented at the time of transmission;
An AV-IF unit which is supplied with a received signal decoded by the MPEG decoder and converts it into an analog signal having a format suitable for displaying an image;
A monitor for displaying the received signal converted by the AV-IF unit
Receiving device having a. An antenna switching circuit of a television broadcast receiving apparatus that receives a broadcast signal and processes a received signal,
A first diode in which a received signal supplied from a first antenna for receiving the television broadcast is connected to an anode terminal;
A second diode connected to an anode terminal, a receive signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal, and a cathode terminal connected to a cathode terminal of the first diode;
A first power supply for supplying a DC voltage to an anode terminal of the second diode and supplying operating power to an LNA built in the second antenna;
A second power supply configured to supply a DC voltage lower than a DC voltage supplied by the first power supply to the anode terminal of the second diode to an anode terminal of the first diode;
Control unit for turning on / off the first power source
And an output signal by switching the received signals shown on the cathode side of the first and second diodes. A tuner module of a television broadcast receiving apparatus for receiving a broadcast signal transmitted by predetermined modulation and processing a received signal,
A first input terminal to which a received signal received by a first antenna for receiving the television broadcast is input;
A second input terminal to which a received signal supplied from a second antenna for receiving the television broadcast and amplified by an LNA incorporating the received signal is input;
A first diode having a received signal supplied from the first input terminal connected to an anode terminal;
A second diode having a received signal supplied from the second input terminal connected to an anode terminal, and a cathode terminal connected to a cathode terminal of the first diode;
A supply terminal of a first power supply supplying a DC voltage to an anode terminal of the second diode and supplying operation power to an LNA built in the second antenna;
A supply terminal of a second power supply for supplying a direct current voltage lower than a direct current voltage supplied by the first power supply to the anode terminal of the second diode to an anode terminal of the first diode;
A frequency converter which is supplied with the received signal shown on the cathode side of the first and second diodes, and frequency-converts it to a predetermined frequency;
A demodulator for supplying a received signal converted by the frequency converter to demodulate the modulation carried out at the time of transmission
Tuner module of a receiving device, characterized in that it has a. The reception device according to claim 2 or 5, wherein the demodulator demodulates modulation by an orthogonal frequency division multiplexing scheme. 8. The tuner module of claim 1, wherein the demodulator demodulates modulation by an orthogonal frequency division multiplexing scheme.

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