JP2006050379A - Television receiver and video system discrimination method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a television receiver capable of performing signal processing according to NTSC, SECAM, and PAL systems each without any discrimination circuits for discriminating the video system of a television from a received television signal. <P>SOLUTION: The television receiver mounted to a mobile unit comprises an NTSC demodulator 8 for performing signal processing corresponding to an NTSC-system video signal; a SECAM demodulator 9 for performing signal processing corresponding to a SECAM-system video signal; a PAL demodulator 10 for performing signal processing corresponding to a PAL-system video signal; a video system discrimination means for discriminating the video system adopted by an area in which the mobile unit exists, based on current position information obtained from a GPS receiver 16 for detecting the current position of the mobile unit; and a supply means for supplying the video signal to one of the demodulators based on the discrimination result. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

The present invention relates to a television receiver and a video format discrimination method, and more particularly to NTSC.
The present invention relates to a television receiver that can handle any of the system, the SECAM system, and the PAL system, and a video system discrimination method for realizing the television receiver.

There are NTSC system, SECAM system, and PAL system as television video systems, and different systems are adopted depending on the country. In Japan and North America, the NTSC method is adopted, while in Europe, the SECAM method and the PAL method are adopted. For example, in France, S
The ECAM method is adopted, and the PAL method is adopted in Germany. NTSC system, SEC
The AM method and the PAL method have different characteristics such as the number of scanning lines, the number of frames, the vertical / horizontal synchronization frequency, and the color difference signal carrying method, and how color information is transmitted especially when performing color broadcasting. The difference of each method appears in the point.

Therefore, in order to realize an appropriate video display, it is necessary to perform signal processing according to each method. For example, in Patent Document 1 below, when a PAL television signal is received,
A PAL system video signal is output to the video demodulation circuit, whereas when a SECAM system television signal is received, a video signal converted from the SECAM system to the PAL system is output to the video demodulation circuit. And a SECAM-compatible television receiver.

This PAL and SECAM compatible television receiver is equipped with a SECAM / PAL discriminating circuit for discriminating whether the received television signal is the PAL system or the SECAM system, and the discrimination result by the SECAM / PAL discrimination circuit Based on PAL, SE
Signal processing corresponding to each CAM system can be performed. Thus, in the conventional television receiver, a discrimination circuit for discriminating the video system of the television from the received television signal is necessary.

By the way, diversity control is required to realize comfortable TV broadcast reception while moving. In TV broadcasting, due to the waveform, radio waves that reach directly and radio waves reflected from buildings and the like overlap, and ghosts are likely to occur on the screen. In order to prevent this, a diversity reception method is effective in which a plurality of antennas are prepared, and the antenna having the best reception state is selected and received (that is, the reception antenna is switched to the optimum one).

However, switching of the receiving antenna is not necessarily performed at any timing, and if the switching of the receiving antenna is performed during an unfavorable period (for example, scanning time), the screen may be disturbed. Therefore, it is important to switch the receiving antenna at an appropriate timing. However, since this appropriate timing varies depending on the video system, if the receiving antenna is switched without considering the video system, the screen may be disturbed.

In addition, in order to realize comfortable TV broadcast reception while moving, it is necessary to maintain stable reception states not only in diversity control but also in various moving places. For this reason, television receivers automatically adjust the gain of the receiver according to the strength of the received radio waves, such as circuits for dealing with radio wave environments unique to moving objects such as strong electric fields, weak electric fields, sudden changes in electric fields, and interference waves. An AGC (Automatic Gain Control) circuit is provided which functions to automatically obtain a constant video detection output by controlling it automatically.

However, also in this gain control, as in the case of diversity control, the appropriate gain control method differs depending on the video system, so if gain control is performed without considering the video system, There is a risk that comfortable TV broadcast reception cannot be realized.
JP 2003-47025 A

Means for solving the problems and their effects

The present invention has been made in view of the above problems, and it is possible to provide an NTSC system, a SECAM system, a PA without using a discrimination circuit that discriminates a television video system from a received television signal.
A television receiver capable of performing signal processing according to each of the L systems and realizing a comfortable television broadcast reception while moving, and a video system discrimination for realizing the television receiver It aims to provide a method.

In order to achieve the above object, a television receiver (1) according to the present invention is an NT that performs signal processing according to an NTSC video signal in a television receiver mounted on a moving body.
SC processing means, SECAM processing means for performing signal processing according to a SECAM video signal, PAL processing means for performing signal processing according to a PAL video signal, and a current position of the mobile body Based on the current position information obtained from the current position detection means, a video system discrimination means for discriminating the video system employed in the area where the moving object is located, and a video based on the discrimination result by the video system discrimination means Supplying means for supplying a signal to any of these processing means is provided.

In other words, the television receiver (1) according to the present invention has different video transmission methods (characteristics) depending on each region (country), but the television receiver is configured to realize signal processing corresponding to each. It is a machine, has processing means corresponding to each method, and has a basic configuration of selecting these processing means according to the current position of the moving body.

According to the television receiver (1), the video system employed in the area where the moving body is located is determined, and based on the determination result, the video signal is converted into NTSC processing means, SEC.
It is supplied to either the AM processing means or the PAL processing means. That is, when the video system employed in the area where the moving object is located is the NTSC system, the video signal is NT
The video system that is supplied to the SC processing means and is employed in the area where the moving object is located is SE.
In the case of the CAM system, the video signal is supplied to the SECAM processing means, and when the video system adopted in the area where the moving body is located is the PAL system, the video signal is PAL.
Supplied to the processing means.

Accordingly, the NTSC video signal is supplied to the NTSC processing means, signal processing (for example, video demodulation processing) is performed in accordance with the NTSC video signal, and the SECAM video signal is supplied to the SECAM processing means. Since the signal processing according to the SECAM video signal is performed, the PAL video signal is supplied to the PAL processing means, and the signal processing according to the PAL video signal is performed. Signal processing according to each of the NTSC system, SECAM system, and PAL system can be performed without providing a discrimination circuit that discriminates the television video system from the received television signal.

In the television receiver (2) according to the present invention, in the television receiver (1), the video system discrimination means is a current position obtained from a current position detection means for detecting a current position of the moving body. Based on the position information, a country detection means for detecting the country in which the mobile body is located, a detection result by the country detection means, and a video format of the television adopted in the country Based on the associated data, it is configured to include a video system detection means for detecting a video system adopted in the country in which the mobile body is located.

According to the television receiver (2), the video system employed in the area where the mobile unit is located is determined by detecting the video system employed in the country where the mobile unit is located. The For example, when the moving body is located in Japan or the United States, the video system adopted in the area where the moving body is located is determined as the NTSC system, and when the moving body is located in France, the moving body is The video system employed in the area where the mobile body is located is determined to be the SECAM system, and when the moving body is located in Germany, the video system employed in the area where the mobile body is located is determined to be the PAL system. As a result, even if the video system adopted in the country changes, it is only necessary to change the data in which the country and the television video system adopted in the country are associated with each other. Can be.

Further, the television receiver (3) according to the present invention is a television receiver (1) or (2).
) Is provided with diversity control means for switching the receiving antenna at a timing suitable for the video signal system based on the discrimination result by the video system discrimination means.

According to the television receiver (3), diversity control is performed by switching the receiving antenna at a timing suitable for the video signal system. Therefore, it is possible to prevent the reception antenna from being switched during an unfavorable period (for example, scanning time), and it is possible to realize comfortable television broadcast reception while moving.

The television receiver (4) according to the present invention includes television receivers (1) to (3).
In any of the above, based on the determination result by the video system determination means, the video signal is detected at a timing suitable for the video signal system to determine the strength of the received radio wave, and the video detection output is based on the determination result AGC control means for performing gain control so as to keep the signal at a predetermined level is provided.

By the way, AGC control determines the strength of the input radio wave using the detected video signal,
Accordingly, it is necessary to control the gain of the tuner or the like, and in order to realize accurate AGC control, it is necessary to accurately determine the strength of the input radio wave. In other words, it is necessary to detect the video signal at an appropriate timing.

According to the television receiver (4), the video signal is detected at a timing suitable for the video signal system to determine the strength of the received radio wave, and the video detection output is maintained at a predetermined level based on the determination result. Thus, gain control is performed. Accordingly, since the strength of the input radio wave can be accurately performed, AGC control with high accuracy can be realized.

The video system discrimination method (1) according to the present invention is obtained from a current position detection means for detecting the current position of the mobile body in the video system discrimination method used for a television receiver mounted on the mobile body. Based on the current position information obtained, the step of detecting the country in which the mobile body is located, the result obtained by the detection, and the country and the television video system adopted in the country are associated with each other And a step of detecting a video system employed in the country in which the mobile body is located based on the data.

According to the video system discrimination method (1), the country in which the mobile body is located is detected, and the video system employed in the country in which the mobile body is located is detected, and the area where the mobile body is located. The video system adopted in is determined. For example, when the moving body is located in Japan or the United States, the video system adopted in the area where the moving body is located is determined as the NTSC system, and when the moving body is located in France, the moving body is The video system employed in the area where the mobile body is located is determined to be the SECAM system, and when the moving body is located in Germany, the video system employed in the area where the mobile body is located is determined to be the PAL system. As a result, it is possible to perform signal processing in accordance with the NTSC system, SECAM system, and PAL system without providing a discrimination circuit that discriminates the television video system from the received television signal, as in the prior art. become.

Embodiments of a television receiver and a video system discrimination method according to the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram schematically showing a main part of the television receiver according to the embodiment (1). In the figure, reference numerals 1a to 1d denote antennas for receiving TV broadcast waves, which are installed at predetermined locations on the vehicle M and directed in a predetermined direction.
d is connected to the antenna switching means 2 so that the antenna signal outputted to the TV tuner 3 can be switched by the antenna switching means 2.

The TV tuner 3 is configured to output an audio signal and a video signal corresponding to a predetermined channel from the received antenna signal. The audio signal output from the TV tuner 3 is output via the audio output unit 4. On the other hand, for the video signal output from the speaker 5 and output from the TV tuner 3, the selection switches 6 and 7 and the NTSC demodulator 8 are provided.
Then, it is output to the display 11 via any one of the SECAM demodulator 9 and the PAL demodulator 10 and displayed as an image, and further to the diversity controller 12 and the AGC controller 13.

The selection switch 6 converts the video signal from the TV tuner 3 into the NTSC demodulator 8 and SECAM.
Output to either the demodulator 9 or the PAL demodulator 10, and the selection switch 7
The video signal demodulated in any of the NTSC demodulator 8, SECAM demodulator 9 and PAL demodulator 10 is output to the display 11. The NTSC demodulator 8 is for demodulating an NTSC video signal, and the SECAM demodulator 9 is
This is for demodulating the SECAM video signal, and the PAL demodulator 10 is for demodulating the PAL video signal.

The microcomputer 14 has a GP for receiving GPS signals from the satellite via the antenna 15.
The S receiver 16 is connected to the memory 17 in which the area data indicating the area of each country and the video format data (see FIG. 2) indicating the video format of the television adopted in each country are stored. The microcomputer 14 can acquire the current position information of the vehicle M, and can determine the country where the vehicle M is located and the video system employed in the country where the vehicle M is located. Yes.

Further, the microcomputer 14 switches the selection switches 6 and 7 based on the discrimination result of the television video system, and the data indicating the discrimination result is transmitted to the diversity control means 12 and the AG.
The data is output to the C control means 13. For example, the microcomputer 14 has an NT video system.
When it is determined that the SC system is selected, the selection switch 6 is controlled so that the input terminal 6i and the output terminal 6n are connected, and the selection switch is connected so that the input terminal 7n and the output terminal 7o are connected. 7 is controlled.

The diversity control means 12 can acquire the video signal output from the TV tuner 3, and determines the reception strength of the antenna signal using this video signal, and if necessary, the TV
The antenna to be connected to the tuner 3 is sequentially switched so that the antenna having the best reception state can be selected. Further, the diversity control means 12 is input with data indicating the discrimination result of the television video system from the microcomputer 14 so that the diversity control means 12 can switch the antenna at a timing suitable for the video system. It has become.

The AGC control means 13 can acquire the video signal output from the TV tuner 3, determines the reception strength of the antenna signal using this video signal, and maintains the video detection output at a predetermined level. The gain of 3 is controlled. Further, the AGC control means 13 is inputted with data indicating the discrimination result of the television video system from the microcomputer 14, so that the AGC control means 13 can detect the video signal at a timing suitable for the video system. It has become. Therefore, even when a video signal of any video system is received, the strength of the input radio wave can be determined with high accuracy, so that accurate AGC control can be realized.

Next, a processing operation [1 performed by the microcomputer 14 of the television receiver according to the embodiment (1).
] Will be described based on the flowcharts shown in FIGS. This processing operation [1] is an operation performed when the power of the television receiver is turned on. First, G
The current position information of the vehicle M obtained from the PS receiver 16 is acquired (step S1), and based on the acquired current position information of the vehicle M and the area data indicating the area of each country stored in the memory 17. Then, the country where the vehicle M is located is detected (step S2), the result obtained by the detection, and the video system showing the video system of the television adopted in each country stored in the memory 17 Based on the data, the video system employed in the country where the vehicle M is located is detected (step S3).

Next, it is determined whether or not the video system employed in the country where the vehicle M is located is the NTSC system (step S4). If it is determined that the video system is the NTSC system, then the selection switch 6 is controlled. Thus, the input terminal 6i and the output terminal 6n are connected (step S5), and the input switch 7n and the output terminal 7o are connected by controlling the selection switch 7 (step S6), and the video system is the NTSC system. Diversity control means 1 is used to indicate that there is data.
2 and AGC control means 13 (step S7). Further, when the video system is the NTSC system adopted in Japan or North America, the video system is not switched while the vehicle M is traveling, so the video system change flag f indicating that is set to “0”. (Step S8).

On the other hand, in step S4, the video system adopted in the country where the vehicle M is located is NTS.
If it is determined that the system is not the C system, then the video system adopted in the country where the vehicle M is located is SE.
It is determined whether or not the CAM method is used (step S9). If it is determined that the CAM method is used, then the selection switch 6 is controlled to connect the input terminal 6i and the output terminal 6s (step S10). ), By controlling the selection switch 7, the input terminal 7s and the output terminal 7o are connected (step S11), and data indicating that the video system is the SECAM system is sent to the diversity control unit 12 and the AGC control unit 13. Output (step S
12). In addition, when the video system is the SECAM system adopted in France, the vehicle M
Since the video system may be switched across the border while traveling, the video system change flag f indicating this is set to “1” (step S13).

On the other hand, if it is determined that the video system employed in the country where the vehicle M is located is not the SECAM system (that is, the PAL system employed in Germany or the like), then the selection switch 6
By controlling the input terminal 6i and the output terminal 6p (step S14).
By controlling the selection switch 7, the input terminal 7p and the output terminal 7o are connected (
In step S15), data indicating that the video system is the PAL system is output to the diversity control means 12 and the AGC control means 13 (step S16). When the video system is the PAL system adopted in France or the like, the video system may be switched across the border while the vehicle M is traveling. 1 "(step S13).

Next, a processing operation [2 performed by the microcomputer 14 of the television receiver according to the embodiment (1).
] Will be described based on the flowchart shown in FIG. This processing operation [2] is an operation performed every predetermined time. First, it is determined whether or not the video system change flag f is “1” (step S21).

If it is determined that the video system change flag f is “1” (that is, the vehicle M is traveling in one of the European countries and the video system may be switched across the border while traveling), GP
The current position information of the vehicle M obtained from the S receiver 16 is acquired (step S22). Based on the acquired current position information of the vehicle M and the area data indicating the area of each country stored in the memory 17. Then, the country in which the vehicle M is located is detected (step S23), and based on the result obtained by the detection, it is determined whether the vehicle M has crossed the border (step S24).

If it is determined that the vehicle M has crossed the border (that is, there is a possibility that the video system is switched), the video system of the television adopted in each country stored in the memory 17 is shown next. Based on the video system data, the video system employed in the country where the vehicle M is located is detected (step S25), and whether the video system has been switched based on the result obtained by the detection. Is determined (step S26).

If it is determined that the video system has been switched, it is then determined whether or not the video system employed in the country where the vehicle M is located is the SECAM system (step S27), and the SECAM system is determined. Then, by controlling the selection switch 6, the input terminal 6i and the output terminal 6s are connected (step S28), and by controlling the selection switch 7,
The input terminal 7s and the output terminal 7o are connected (step S29), and data indicating that the video system is the SECAM system is output to the diversity control unit 12 and the AGC control unit 13 (step S30).

On the other hand, in step S27, the video system adopted in the country where the vehicle M is located is SE.
If it is determined that it is not the CAM system (that is, the PAL system adopted in Germany or the like), then the input terminal 6i and the output terminal 6p are connected by controlling the selection switch 6 (step S31). ), By controlling the selection switch 7, the input terminal 7p and the output terminal 7o are connected (step S32), and data indicating that the video system is the PAL system is sent to the diversity control means 12 and the AGC control means 13. Output (step S3
3).

In step S21, the video system change flag f is not “1” (that is, the vehicle M is traveling in Japan or North America that employs the NTSC system as the video system, and the video system is switched during traveling. If it is determined that the vehicle M has not crossed the border in step S24, or if it is determined in step S26 that the video system has not been switched, the processing operation after step S27 is performed. Since there is no need to perform this, the processing operation [2] is terminated as it is.

According to the television receiver according to the above embodiment (1), the video system employed in the country where the vehicle M is located is determined, and the video signal is converted to the NTSC demodulator 8 based on the determination result.
, SECAM demodulator 9 and PAL demodulator 10. That is, when the video system adopted in the country where the vehicle M is located is the NTSC system, the video signal is N
The video system supplied to the TSC demodulator 8 and adopted in the country where the vehicle M is located is SECAM.
In the case of the system, the video signal is supplied to the SECAM demodulator 9, and when the video system adopted in the country where the vehicle M is located is the PAL system, the video signal is supplied to the PAL demodulator 10.

Accordingly, the NTSC video signal is supplied to the NTSC demodulator 8 and subjected to video demodulation processing in accordance with the NTSC video signal. The SECAM video signal is sent to the SECAM demodulator 9.
And is subjected to video demodulation processing according to the SECAM video signal, and the PAL video signal is supplied to the PAL demodulator 10 and subjected to video demodulation processing according to the PAL video signal. Therefore, the signal processing according to the NTSC system, the SECAM system, and the PAL system can be performed without providing a discrimination circuit that discriminates the television video system from the received television signal as in the prior art.

Further, the diversity control means 12 receives data indicating the discrimination result of the television video system from the microcomputer 14, and the diversity control means 12 switches the receiving antenna at a timing suitable for the video signal system. Control is performed. Therefore, it is possible to prevent the reception antenna from being switched during an unfavorable period (for example, scanning time), and it is possible to realize comfortable television broadcast reception while moving.

In addition, since the data indicating the discrimination result of the television video system is input from the microcomputer 14 to the AGC control means 13, the AGC control means 13 is accurate regardless of which video signal is received. Good gain control is performed. Therefore, comfortable television broadcast reception while moving can be realized.

It is the block diagram which showed roughly the principal part of the television receiver which concerns on embodiment (1) of this invention. It is the figure which showed an example of the data memorize | stored in the memory in the television receiver which concerns on embodiment (1). It is the flowchart which showed the processing operation which the microcomputer in the television receiver concerning Embodiment (1) performs. It is the flowchart which showed the processing operation which the microcomputer in the television receiver concerning Embodiment (1) performs. It is the flowchart which showed the processing operation which the microcomputer in the television receiver concerning Embodiment (1) performs.

Explanation of symbols

2 Antenna switching means 3 TV tuners 6 and 7 Select switch 8 NTSC demodulator 9 SECAM demodulator 10 PAL demodulator 12 Diversity control means 13 AGC control means 14 Microcomputer 16 GPS receiver 17 Memory

Claims (5)

In a television receiver mounted on a moving object,
NTSC processing means for performing signal processing according to an NTSC (National Television System Committee) video signal;
SECAM processing means for performing signal processing according to an SECAM (Sequential couleur a Memoire) video signal;
PAL processing means for performing signal processing according to a PAL (Phase Alternation by Line color television) video signal;
Based on current position information obtained from current position detection means for detecting the current position of the mobile body, video system determination means for determining the video system employed in the area where the mobile body is located;
A television receiver comprising: supply means for supplying a video signal to one of these processing means based on a result of discrimination by the video format discrimination means. The video format discrimination means is
Based on current position information obtained from current position detection means for detecting the current position of the mobile object, a country detection means for detecting a country in which the mobile object is located;
The video system adopted in the country in which the moving object is located based on the detection result by the country detection means and the data in which the country and the video system of the television adopted in the country are associated with each other 2. The television receiver according to claim 1, further comprising a video system detecting means for detecting the video. 3. The television according to claim 1, further comprising diversity control means for switching a receiving antenna at a timing suitable for a video signal system based on a determination result by the video system determination means. Receiving machine. Based on the discrimination result by the video system discrimination means, the video signal is detected at a timing suitable for the video signal system to determine the strength of the received radio wave, and the video detection output is maintained at a predetermined level based on the determination result. The television receiver according to claim 1, further comprising AGC control means for performing gain control. In a video format discrimination method used for a television receiver mounted on a moving object,
Detecting a country in which the moving body is located based on current position information obtained from current position detecting means for detecting a current position of the moving body;
Based on the result obtained by the detection and the data in which the country and the video system of the television adopted in the country are associated with each other, the video system adopted in the country in which the moving body is located And a detecting step.

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