JPH04369189A - Television receiver - Google Patents

Abstract

PURPOSE:To obtain an video output and an audio output at all times by selecting the reception state of a TV broadcast signal by other broadcast system automatically when the reception state of a TV broadcast signal of one broadcast system is deteriorated and the reception is inadequate. CONSTITUTION:An antenna receives a TV signal comprising an analog signal and a digital signal from one and same broadcast station, a tuner 2 receives the TV broadcast signal comprising the analog signal, and a signal processing circuit 4 decodes the TV broadcast signal. Furthermore, a tuner 3 receives the TV broadcast signal comprising the digital signal, and a signal processing circuit 5 decodes the TV broadcast signal. In this case, a detection circuit 8 detects a frequency of errors in a data comprising the digital signal from the tuner 3 and when the reception state is excellent, a control circuit 9 allows a changeover circuit 6 to select the circuit 5 thereby giving the TV broadcast comprising the digital signal to an output device 7. When the reception state is deteriorated, the control circuit 9 allows the changeover circuit 6 to select the circuit 4 thereby giving the TV broadcast comprising the analog signal to the output device 7.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television receiver that can be applied to a simulcast broadcast system in which the same broadcast program is simultaneously broadcast using different television broadcast systems.

0002

2. Description of the Related Art In order to realize high-quality television broadcasting, there is a method of simultaneously broadcasting the same program content in a completely different manner with improved quality, which is called a simulcast method. On the other hand, with recent advances in digital technology, the feasibility of television broadcasting using digital transmission is increasing, and in the future, simulcast broadcasting systems that simultaneously transmit the current analog television broadcasting system and digital television broadcasting system will become a reality. It's promising.

[0003] In this broadcasting system, in the current broadcasting using analog signals, even if the reception condition deteriorates, the content of the broadcast can be generally understood only by deteriorating the decoded signal accordingly. On the other hand, digital transmission has a characteristic that due to the effect of the error correction code, the decoded signal does not deteriorate even if the reception condition worsens to a certain extent, but when the reception condition deteriorates beyond that level, the decoded signal deteriorates rapidly. Moreover, it is considered that the digital transmission level needs to be kept as low as possible in order to avoid interfering with adjacent channels, and there is a high possibility that the reception condition of digital transmission will deteriorate.

0004

[Problems to be Solved by the Invention] As mentioned above, the simulcast broadcasting system that simultaneously broadcasts television broadcasting systems using analog signals and digital signals is promising, but television broadcasting using digital signals is No consideration was given to the deterioration of the reception condition of digital transmission.

[0005]

[Means for Solving the Problems] The present invention was invented in order to solve the above-mentioned conventional problems.
A television receiver for receiving simulcast broadcasts simultaneously transmitted in a television broadcasting system, comprising a decoder device for each of the television broadcasts in the first and second television broadcasting systems, and the second television broadcasting system. reception state detection means for detecting the reception state of television broadcasting according to the system;
a selection means for automatically selecting one of the decoded signals of the television broadcast according to the first or second television broadcasting system from the detection result of the reception state of the television broadcast according to the television broadcasting system. This is to provide a John receiver.

Further, in the present invention, the first television broadcasting method is a television broadcasting using an analog signal, and the second television broadcasting method is a television broadcasting using a digital signal, and the reception state detecting means is a television broadcasting using a digital signal. The present invention also provides a television receiver that detects the frequency of errors in television broadcast data of the second television broadcast system.

[0007]

[Operation] Therefore, according to the present invention, the reception condition of television broadcasting of one broadcasting method in simulcast is detected, and if the reception condition is determined to be good, high-quality decoding of that broadcasting method is performed. If it is determined that the reception condition of the signal is poor, a decoded signal of another broadcasting system is selected and video and audio are output.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a block electrical circuit diagram showing an embodiment of a television receiver according to the present invention, in which 1 is an antenna, and 2 is an antenna in the current television broadcasting system (first television broadcasting system). a first tuner for receiving a transmitted analog television broadcast signal; 3;
is a second tuner that receives a digital television broadcast signal transmitted in another television broadcast system (second television broadcast system), and the broadcast signal is the analog signal television broadcast signal. This shows the same broadcast program transmitted from the same broadcast station as the signal. 4 is a first unit that converts the current analog television broadcast signal received by the first tuner 2 into a decoded signal, that is, a video signal and an audio signal, which can be output to a cathode ray tube and a speaker using a well-known method. The signal processing circuit constitutes a first decoder device together with the first tuner 2 described above.

5 inputs a digital television broadcast signal received by the second tuner 3;
A second processing unit performs processing such as error correction, decoding, and D/A conversion on the input signal and converts it into a decoded signal, that is, a video signal and an audio signal that can be output to a cathode ray tube and a speaker.
The signal processing circuit constitutes a second decoder device together with the second tuner 3.

Reference numeral 6 denotes a switching circuit which selects the decoded signals from the first and second signal processing circuits 4 and 5 and supplies them to the output device 7 at the next stage, and the switching operation is performed by a control circuit 9 to be described later. controlled by The output device 7 is a video output device such as a cathode ray tube and an audio output device such as a speaker.

Reference numeral 8 denotes a reception state detection circuit which outputs a signal indicating whether the reception state is good or bad by detecting the frequency of errors in the data of the digital signal output from the second tuner 3. The control circuit 9 controls the television broadcast using digital signals based on the signal indicating the quality of the reception state of the detection circuit 8, that is, when the reception state is good,
If the reception condition is poor, a control signal is output to the switching circuit 6 to select television broadcasting using analog signals.

[0012] Since the present invention is configured as described above, the antenna receives each analog and digital television broadcast signal transmitted from the same broadcasting station, and based on this receives the first television broadcast signal. The tuner 2 receives a television broadcast signal in the form of an analog signal, and the first signal processing circuit 4 decodes the television broadcast signal. Further, the second tuner 3 receives television broadcast signals in the form of digital signals, and the second signal processing circuit 5 decodes the digital television broadcast signals.

At this time, the reception state detection circuit 8 looks at the digital signal obtained from the second tuner 3, detects the error frequency of the data, and if the reception state is good as a result, the control circuit 9 switches the switching circuit. 6 selects the second signal processing circuit 5 to supply a digital television broadcast signal to the output device 7. If the reception condition is poor, the control circuit 9 causes the switching circuit 6 to select the first signal processing circuit 4 and supply the analog television broadcast signal to the output device 7.

[0014]

[Effects of the Invention] Since the present invention is configured as described above, when the reception condition of a television broadcast signal by one broadcasting method deteriorates and becomes inappropriate, it automatically switches to another broadcasting method. Because the system switches to receive television broadcast signals, video and audio are always output without loss of broadcast content.

[Brief explanation of drawings]

FIG. 1 is a block electrical circuit diagram showing an embodiment of a television receiver according to the present invention.

[Explanation of symbols]

1 Antenna 2 First tuner 3 Second tuner 4 First signal processing circuit 5 Second signal processing circuit 6 Switching circuit 7 Output device 8 Reception status detection circuit 9 Control circuit

Claims (2)

[Claims] Claim 1. A television receiver that receives simulcast broadcasting in which the same broadcast program as a first television broadcasting system is simultaneously transmitted in a second television broadcasting system, wherein the first and second television broadcasting a decoder device for each of the television broadcasting systems, a reception state detection means for detecting a reception state of the television broadcast according to the second television broadcasting method, and a reception state detection means for detecting the reception state of the television broadcasting according to the second television broadcasting method. a selection means for automatically selecting one of the decoded signals of the television broadcast of the first or second television broadcasting system based on the detection result of the reception state of the television broadcast by the television broadcasting system. John receiver. 2. The first television broadcasting method is a television broadcasting using an analog signal, and the second television broadcasting method is a television broadcasting using a digital signal, and the receiving state detecting means is a television broadcasting using a digital signal. 2. The television receiver according to claim 1, wherein the television receiver is for detecting error frequency of data of television broadcasting according to the television broadcasting system.