CN100553310C - Method for receiving and switching digital/analog signal and TV for realizing this function - Google Patents

Abstract

The invention provides a TV capable of receiving and switching digital/analog signals, comprising: a TV tuner for receiving and processing digital TV signals or analog TV signals; a switching unit for controlling the TV tuner to convert the processed The digital TV signal is transmitted to the digital receiving part, or the processed analog TV signal is transmitted to the analog receiving part; the digital receiving part is used to decode the signal transmitted by the TV tuner, and transmit the decoded audio and video signals For the analog receiving part to process; the analog receiving part is used to decode the signal transmitted by the TV tuner, and process the decoded audio and video signals transmitted by the digital receiving part for audio playback and video playback . A switching method is also provided correspondingly. The invention can realize the compatibility of the digital/analog systems and reduce the production cost of the TV.

Description

Method for receiving and switching digital/analog signal and TV for realizing this function

technical field

The invention relates to the technical field of television, in particular to a method for receiving and switching digital/analog signals and a television for realizing the function.

Background technique

For a TV installed with a TV tuner (or tuner) with functions of receiving digital TV signals and analog TV signals, not only analog TV signals but also digital TV signals can be received. Correspondingly, this type of TV also uses two processing circuits inside, one is used to process analog TV signals for display on the display screen and audio playback by speakers; the other is used to process digital TV signals, which are processed by the display screen Display and play audio from speakers.

The design of the two-way processing circuit is adopted because the analog TV signal processing part and the digital TV signal processing part respectively correspond to two sets of control systems. Although the two sets of control systems are both implemented with the structure of the I ² C bus, but because the two sets of control systems are not compatible, the control signals to the respective circuits are also different, so two sets of processing circuits have to be set up. This results in many components not being able to be shared. For example, the above-mentioned digital signal processing circuit part is used to process digital TV signals, and the analog signal processing circuit part is used to process analog TV signals. Components increase the production cost of TV.

Contents of the invention

In view of this, the present invention provides a switching method for digital/analog signal reception and a TV for realizing the function, so as to realize the maximum combination of digital/analog two systems and reduce the production cost of the TV.

The television provided by the present invention that can realize the switching function of digital/analog signal reception includes:

TV tuners for receiving and processing digital TV signals or analog TV signals;

A switching unit, used to control the TV tuner to transmit the processed digital TV signal to the digital receiving part, or transmit the processed analog TV signal to the analog receiving part;

The digital receiving part is used to decode the signal transmitted by the TV tuner, and pass the decoded audio and video signals to the analog receiving part for processing;

The analog receiving part is used to decode the signal transmitted by the TV tuner, and process the decoded audio and video signal transmitted by the digital receiving part for audio and video playback.

Wherein, the digital receiving part includes:

The digital signal demodulation unit is used to demultiplex the signal processed by the TV tuner and output the transport stream TS;

The digital video decoding unit is used to decode the TS stream signal delivered by the digital signal demodulation unit to output the digital video stream signal, and transmit it to the video processing unit of the analog receiving part for processing;

The digital audio decoding unit is used to decode the TS stream signal delivered by the digital signal demodulation unit to output the digital audio stream signal, and transmit it to the audio processing unit of the analog receiving part for processing;

The digital mode controller is used to realize the control of the digital signal demodulation unit, the digital video decoding unit, the digital audio decoding unit and the switching unit, and communicate with the analog mode controller.

Wherein, it further includes an I ² C bus, which is connected with the digital mode controller, digital signal demodulation unit, digital video decoding unit, digital audio decoding unit, switching unit and TV tuner.

Wherein, the analog receiving part includes:

The analog signal demodulation unit is used to demodulate the signal processed by the TV tuner and output the intermediate frequency signal;

The analog video decoding unit is used to decode the intermediate frequency signal demodulated by the analog signal demodulation unit to output the video stream signal, and transmit it to the video processing unit;

The analog audio decoding unit decodes the intermediate frequency signal demodulated by the analog signal demodulation unit to output the audio stream signal, and transmits it to the audio processing unit;

A video processing unit, which processes the transmitted video stream signal for video playback;

The audio processing unit processes the transmitted audio stream signal for audio playback;

The analog mode controller is used to control the analog signal demodulation unit, analog video decoding unit, analog audio decoding unit, video processing unit, audio processing unit and switching unit, and communicate with the digital mode controller.

Wherein, it further includes an I ² C bus, connecting the analog mode controller, analog signal demodulation unit, analog video decoding unit, analog audio decoding unit, video processing unit, audio processing unit, switching unit and TV tuner.

The present invention accordingly provides a method for receiving and switching digital/analog signals, including:

Receive an instruction to switch between digital/analog signal reception;

Control the current digital/analog viewing mode to switch to analog/digital viewing mode.

Wherein, in the current state of receiving digital TV signals, the step of receiving the signal switching instruction includes: receiving the switching instruction by the analog mode controller and transmitting it to the digital mode controller;

The step of controlling the switching from the current digital viewing mode to the analog viewing mode includes: the digital mode controller sends a switching instruction to the switching unit, and the switching unit controls the TV tuner to receive the analog TV signal and send it to the analog receiving part.

Wherein, in the current state of receiving analog TV signals, the step of receiving a signal switching instruction includes: receiving the switching instruction by an analog mode controller;

The step of controlling the switching from the current analog viewing mode to the digital viewing mode includes: the analog mode controller sends a switching instruction to the switching unit, and the switching unit controls the TV tuner to receive digital TV signals and send them to the digital receiving part.

Wherein, it further includes: the digital audio and video signals demodulated and decoded by the digital receiving part are sent to the analog receiving part for processing for playing and displaying.

As can be seen from the above, the present invention can realize the switching of digital TV signal or analog TV signal reception through the control of the switching unit to the TV tuner, and open and control the received signal to output to the digital receiving part or analog receiving part of the TV. In addition, the video stream and audio stream decoded by the digital receiving part of the present invention are sent to the analog receiving part for processing. After processing, they are displayed and played by the TV, and the digital receiving part does not need additional processing circuits, which simplifies the circuit and reduces the cost of the TV. Moreover, due to the existence of the switching unit, the respective systems of the digital receiving part and the analog receiving part maintain their respective functions, and the two systems communicate through the serial port between the CPUs, realizing the interaction of the signal commands of the two systems.

Description of drawings

Fig. 1 is a schematic diagram of the television circuit of the present invention;

Fig. 2 is a schematic diagram of a specific embodiment of the present invention.

Detailed ways

1 shows the schematic diagram of the circuit inside the TV of the present invention. As shown in the figure, the TV of the present invention includes a display screen, a speaker, a TV tuner 110, a switching unit 120, a digital receiving part 140 and an analog receiving part 130. in,

The TV tuner 110 is configured to receive and process digital TV signals and analog TV signals.

The switching unit 120 is used to control the processed analog signal output by the TV tuner 110, that is, the video and audio baseband signal, to the analog signal demodulation unit 131, or the processed digital signal, that is, the modulated multiplexed transport stream (TS) , to the digital signal demodulation unit 141.

Digital receiving section 140 includes:

A digital signal demodulation unit 141, configured to demultiplex the multiplexed TS stream signal output by the TV tuner 110, and output a TS stream (transport stream);

The digital video decoding unit 142 is used to decode the TS stream delivered by the digital signal demodulation unit 141, output the digital video stream signal, and send it to the video processing unit 134 of the analog receiving part 130 for processing;

The digital audio decoding unit 143 is used to decode the TS stream delivered by the digital signal demodulation unit 141, output the digital audio stream signal, and send it to the audio processing unit 135 of the analog receiving part 130 for processing;

The digital mode controller 144 is used for controlling the digital signal demodulation unit 141 , the digital video decoding unit 142 , the digital audio decoding unit 143 and the switching unit 120 . The transmission of control signals between the digital mode controller 144 and these units can be realized by using an I ² C bus.

The analog receiving part 130 includes:

An analog signal demodulation unit 131, configured to demodulate the analog signal transmitted by the TV tuner 110, and output an intermediate frequency signal, that is, an analog signal stream;

The analog video decoding unit 132 is used to decode the intermediate frequency signal demodulated by the analog signal demodulation unit 131, output the video stream signal, and send it to the video processing unit 134; wherein, the demodulation process includes decoding bright color separation, chroma resolution Operations such as tuning and encoding.

The analog audio decoding unit 133 decodes the intermediate frequency signal demodulated by the analog signal demodulation unit 131, outputs the audio stream signal, and sends it to the audio processing unit 135;

The video processing unit 134 processes the transmitted video stream signal to generate a signal capable of driving the display screen to play the video; the processing process includes image scaling, frame rate conversion, signal processing, etc.;

The audio processing unit 135 processes the transmitted audio stream signal to play the audio by the speaker, the processing process includes power amplifier, D/A conversion, etc.;

The analog mode controller 136 is used to control the analog signal demodulation unit 131, the analog video decoding unit 132, the analog audio decoding unit 133, the video processing unit 134, the audio processing unit 135 and the switching unit 120, and communicate with the digital mode controller 144 communicates, and transmits the command to the digital mode from the remote controller or keyboard keys to the digital mode controller 144. The control of these units by the analog mode controller 136 can be implemented in an I ² C manner.

The digital mode controller 144 can communicate with the analog mode controller 136 through a serial port. In the analog TV signal receiving mode, the analog mode controller 136 receives and recognizes an instruction from a remote controller or a keyboard, and when the instruction is to switch to a digital receiving mode, the analog mode controller 136 sends a switching instruction to the switching unit 120, and the switching unit 120 controls the TV tuner 110 to switch to receive the digital TV signal and transmit it to the digital receiving part 140 , and at this time the TV tuner 110 will receive the digital TV signal and input it to the digital signal demodulation unit 141 .

In the digital TV signal receiving mode, when the analog mode controller 136 receives an instruction from the remote controller or the TV keyboard, it is transmitted to the digital mode controller 144 through the serial port, and the digital mode controller 144 receives and performs corresponding operations To realize the control in digital mode. For example, when the remote control instruction is switching, the digital mode controller 144 sends a switching instruction to the switching unit 120 after receiving the instruction transmitted from the analog mode controller 136, and the switching unit 120 controls the TV tuner 110 to switch and receive the analog TV signal and Then the TV tuner 110 will receive the analog TV signal and input it to the analog signal demodulation unit 131 .

Fig. 2 shows a specific embodiment of the present invention,

As shown in the figure, for the digital receiving part, the function of the digital signal demodulation unit is realized by a multiplexing decoding chip, such as a chip of model TDA10046. The functions of digital audio decoding unit, digital video decoding unit and digital mode controller are realized by UPD6111X chip. Since the conversion of digital audio to analog audio is a relatively mature technology, the example in Figure 2 is equipped with a digital/analog conversion chip in the digital receiving part, such as the model HT82V731 chip, which is used to convert digital audio to analog audio signals and transmit Give the TPA8947 chip.

For the analog receiving part, the functions of the analog audio decoding unit, analog video decoding unit, audio processing unit and video processing unit are realized by the main control chip, such as the CX32 chip. Use a switching matrix chip, such as a CD4053 chip, to realize the function of the switching unit. Use intermediate frequency decoding chip, such as TDA9885/6 chip to realize the function of analog signal demodulation unit. The audio processing unit uses a power amplifier chip, such as the TPA8947 chip, to realize audio power amplifier and other functions.

As can be seen above, for the digital receiving part, the switching unit CD4053 chip controls the TV tuner to receive digital signals, and the digital signals are transmitted from the TV tuner to the TDA10046 chip for TS stream demultiplexing, and then the demodulated TS stream is sent to the UPD6111X chip for processing. Decoding of digital video and digital audio, the decoded digital video stream is transmitted to the CX32 chip for video processing to be displayed on the display screen, and the decoded digital audio is converted into an analog signal by the HT82V731 chip and transmitted to the AZ4558 chip for processing. The commands from the external infrared remote controller or keyboard are received and recognized by CX32, and sent to the UPD6111X chip.

For the analog receiving part, the switching unit controls the TV tuner to receive the analog signal and transmit it to the TDA9885/6 chip for demodulation. The demodulated signal is decoded and processed by the CX32 chip and then displayed on the display screen. The decoded audio After being passed to the AZ4558 chip for processing, it will be played by the speaker. The CX32 chip also receives and recognizes other commands from infrared remote controls and keyboards.

As can be seen from the above, the circuit of the present invention maintains the function of the analog receiving part, such as receiving and identifying instructions for remote controllers or keyboards is still implemented by the analog board, and video processing and audio processing are also still implemented by the analog receiving part. Part of the remote control or keyboard command recognition unit, video processing or audio processing unit is set separately. The circuit is simplified, and the production cost of the TV is reduced.

Moreover, when the control units of the two receiving parts communicate with each other, standard serial ports can be used for communication. It is only necessary to set the corresponding command interface, and there is no need to modify the respective control systems. The analog receiving part is still controlled by the analog control unit. , the digital receiving part is still controlled by the digital control unit.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the utility model. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection.

Claims (4)

1. A television capable of implementing digital/analog signal reception switching function, comprising:

a TV tuner (110) for receiving and processing a digital TV signal or an analog TV signal;

a switching unit (120) for controlling the TV tuner (110) to transmit the processed digital TV signal to the digital receiving part (140) or to transmit the processed analog TV signal to the analog receiving part (130);

a digital receiving part (140) for decoding the signal transmitted from the TV tuner (110) and transferring the decoded audio and video signals to an analog receiving part (130) for processing; and

an analog receiving part (130) for decoding the signal transmitted from the TV tuner and processing the decoded audio and video signals transmitted from the digital receiving part (140) for audio and video playback;

the digital receiving section (140) includes:

a digital signal demodulation unit (141) for demultiplexing the signal processed by the TV tuner (110) and outputting a transport stream TS;

a digital video decoding unit (142) for decoding the TS stream signal transmitted by the digital signal demodulation unit (141) and outputting a digital video stream signal, and transmitting the digital video stream signal to a video processing unit (134) of the analog receiving part (130) for processing;

a digital audio decoding unit (143) for decoding the TS stream signal transmitted by the digital signal demodulation unit (141) and outputting a digital audio stream signal, and transmitting the digital audio stream signal to an audio processing unit (135) of the analog receiving part (130) for processing; and

the digital mode controller (144) is used for realizing the control of the digital signal demodulation unit (141), the digital video decoding unit (142), the digital audio decoding unit (143) and the switching unit (120), and communicating with the analog mode controller (136);

the analog receiving section (130) includes:

an analog signal demodulation unit (131) for demodulating the signal processed by the TV tuner (110) and outputting an intermediate frequency signal;

an analog video decoding unit (132) for decoding the intermediate frequency signal demodulated by the analog signal demodulation unit (131) to output a video stream signal, and transmitting the video stream signal to the video processing unit (134);

an analog audio decoding unit (133) which decodes the intermediate frequency signal demodulated by the analog signal demodulation unit (131) to output an audio stream signal, and transmits the audio stream signal to the audio processing unit (135);

a video processing unit (134) for processing the transmitted video stream signal to play video;

an audio processing unit (135) for processing the transmitted audio stream signal to play audio; and

and the analog mode controller (136) is used for realizing the control of the analog signal demodulation unit (131), the analog video decoding unit (132), the analog audio decoding unit (133), the video processing unit (134), the audio processing unit (135) and the switching unit (120) and communicating with the digital mode controller (144).

2. The television of claim 1,

the switching unit (120) is a CD4053 chip;

the digital signal demodulation unit (141) is a TDA10046 chip and is connected with the TV tuner (110);

the digital video decoding unit (142), the digital audio decoding unit (143) and the digital mode controller (144) are realized by a UPD6111X chip, and are connected with a CD4053 chip and a TDA10046 chip;

the analog signal demodulation unit (131) is a TDA9885/6 chip and is connected with the TV tuner (110);

the analog video decoding unit (132), the analog audio decoding unit (133), the video processing unit (134), the audio processing unit (135) and the analog mode controller (136) are realized by a CX32 chip and are connected with a CD4053 chip, a TDA9885/6 chip and a UPD6111X chip.

3. The television of claim 1, further comprising I²A C bus connected to the digital mode controller (144), the digital signal demodulation unit (141), the digital video decoding unit (142), the digital audio decoding unit (143), the switching unit (120), and the TV tuner (110);

the analog mode controller (136), the analog signal demodulation unit (131), the analog video decoding unit (132), the analog audio decoding unit (133), the video processing unit (134) and the audio processing unit (135) are also connected.

4. A method of digital/analog signal reception switching, comprising:

under the current digital TV signal receiving state, the analog mode controller (136) receives a digital/analog signal receiving switching instruction and transmits the digital/analog signal receiving switching instruction to the digital mode controller (144);

the digital mode controller (144) sends a switching instruction to the switching unit (120), and the switching unit (120) controls the TV tuner (110) to receive the analog TV signal and sends the analog TV signal to the analog receiving part (130) for processing;

the analog receiving section (130) performs processing including: an analog signal demodulation unit (131) demodulates the received analog TV signal; then, the analog audio decoding unit (133) and the analog video decoding unit (132) respectively decode and output audio and video stream signals; then respectively transmitting the audio frequency processing unit (135) and the video frequency processing unit (134) to process so as to play and display the audio frequency and the video frequency;

in the current analog TV signal receiving state, an analog mode controller (136) receives a digital/analog signal receiving switching instruction;

the analog mode controller (136) sends a switching instruction to the switching unit (120), and the switching unit (120) controls the TV tuner (110) to receive the digital TV signal and sends the digital TV signal to the digital receiving part (140) for processing;

the digital receiving section (140) performs processing including: a digital signal demodulation unit (141) demodulates the received digital TV signal; then a digital audio decoding unit (143) and a digital video decoding unit (142) respectively decode and output digital audio and video stream signals; and then processed by an audio processing unit (135) and a video processing unit (134) of the analog receiving part (130) respectively to perform audio and video playback and display.

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