JPH02205196A - Transmission system for television signal - Google Patents

Abstract

PURPOSE:To obtain a picture close to an HDTV by eliminate necessity to simultaneously broadcast an existing signal and a wide aspect signal and presenting one channel, which is used for an existing broadcast, to improve resolution. CONSTITUTION:For the horizontal high definition signal of a wide TV reinforcing signal, high definition signals YH and CH are taken out of a time division component signal by a BPF 15 of a passing band 4.5-7.5MHz. By modulating a frequency fS by a modulator 16 according to this high definition signal, the frequency of the high definition signal is shifted to a direct current and signals YH' and CH' are obtained. On the other hand, a signal for successive scan conversion in a reception side is converted into a YIQ signal by an RGB/YIQ converter 8 after that, it is obtained by a scan conversion reinforcing signal generator 17. This signal is passed through a time division multiplexing circuit 7, defined as the time division component signal and passed through an LPF 18 of the passing band 3MHz and an LD signal is obtained. For the YH' and CH' signals and the LD signal, an RF1 is orthogonally modulated by a QM modulator 19 and thus, the wide TV reinforcing signal is obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wide aspect television transmission system that is compatible with current television.

[Conventional technology]

This is a compatible method for transmitting wide aspect television signals in one channel.

For example, in the three-dimensional frequency domain, there is a method of frequency multiplexing side panel information in areas that are not effectively used, horizontal
A method of multiplexing side panel information in a vertical overscan area or a synchronization period has been proposed.

When using 2 channels (or 1.5 channels), one channel broadcasts the current broadcast, and the other channel transmits side panel information to achieve wide aspect and information for high definition. There is a way. It was also submitted to the FCC TV Committee as a method with a different perspective.

The present invention relates to this method. [Problems to be solved]] In the above-mentioned conventional technology, complicated processing is performed in order to obtain a resolution higher than that of current broadcasting in one channel for wide aspect.

Using a 1125/2 to 1/60 HDTV signal as a source, the signal is first divided into high and low frequencies with 200 KHz as the boundary. The low range is transmitted digitally, and the high range is transmitted analog. Regarding high frequency signals, efforts have been made to transmit HDTV signals with a band of 30 MHz at 6 MHz.

An object of the present invention is to provide a television signal transmission system that achieves image quality close to HDTV through simple signal processing.

[Means to solve the problem]

In order to achieve the above purpose, the aim is to increase the resolution in two stages.

First, in the first stage, the current signal and the wide-spectrum signal are simultaneously broadcast, and the signal is divided into a wide-spectrum luminance signal and a color difference signal, and is time-division multiplexed and transmitted. Therefore, the brightness will be lower than that of current televisions due to the spread of the signal on both sides and the reduction in time occupied by the brightness signal due to time division multiplexing, but wide aspect TVs
As the first stage of implementation, we will accept a reduction in resolution.

In the second stage, when wide aspect TV becomes widespread, there will be no need for simultaneous broadcasting. Therefore, one channel that was currently used for broadcasting will be used to improve the resolution.

[Effect]

In the first stage of introducing wide aspect TV, since time-division component signals are used, it is not possible to obtain clear wide aspect images without crosstalk between luminance signals and color signals.

Additionally, the second stage of implementation will improve resolution.

You can watch videos close to KDTV studio standards.

Here, we have shown a two-stage installation method, but it is also possible to consider it as a wide aspect TV only in the first stage. It is also possible to realize high-resolution wide aspect TV using channels).

〔Example〕

First, a conceptual diagram of the present invention is shown in FIG. 1. (a) is an outline of the first stage of wide aspect TV.

The broadcast station simultaneously broadcasts the current TV broadcast and the wide TV broadcast (time-division analog component). Therefore, current TV receivers can receive conventional TV broadcasts. On the other hand, the wide TV receiver l receives the signal of CH2 and displays a wide aspect image.

(b) is a schematic diagram of the second stage. A wide TV broadcast and a wide TV reinforcement signal are transmitted from the broadcast station. Current receivers are not compatible and require a converter. Wide TV receiver! In this case, an image of the same quality as in (a) is obtained. In the wide TV receiver, CH
By receiving both the I and CH2 signals, it is possible to obtain (a) a higher definition wide 1゛v image.

First, we will show an example of the transmitter and wide TV receiver I shown in FIG. 1(a).
Now let's consider the time-sharing analog component shown in Figure 2.
Transmits wide aspect signals.

FIG. 3(a) shows an embodiment of the transmitter. The progressive scanning wide camera KGB output 1 is passed through a progressive scanning/interlaced scanning converter 2. Here, aliasing distortion caused by interlaced scanning is removed at the stage of the progressive scanning signal, rather than mere thinning. In the route to create the current N''r SC signal, the aspect ratio converter 3 extracts only the 4:3 area at the center of 16=9 as shown in Figure 3(b) and stretches it for one hour. Make it the same format as the camera's RGB output. Then, N T
The current NT SC signal is obtained through an SC signal encoder 4 and an LPF 5 with a cutoff frequency of 4.2 MHz.

- On the other hand, in order to obtain a wide 1゛V signal, the output of the scan converter 2 is first passed through the ROB/YIQ conversion circuit 6, and the YIQ
Obtaining the signal In order to convert this signal into the signal shown in Figure 2,
Time division multiplexing Each time is compressed and time division multiplexed. after that,
Filter with 4.5MHz LPF8. Since the sound signal is time-division multiplexed, it can be used up to 4.5 MHz. As a result, one time-division component signal is obtained. Both signals are transmitted by modulating the RF carrier in the same manner as in current broadcasting.

Here, the bandwidth of CH2 is 9MH for high definition.
If 2E can be used, the cutoff frequency of LPF8 is 7.5M.
Hz. In addition, although the progressive scanning signal is considered as the source here, the third
It is also possible to connect directly after the image scanning converter 2.

An embodiment of the receiver is shown in FIG. 4. First, the signal passes through a tuner 9 and is RF demodulated to obtain the signal shown in FIG. YI
A Q separation/time expansion circuit 10 extracts each YIQ signal and expands it by one hour. Thereafter, the interlaced scanning signal is converted into a progressive scanning signal in the scanning conversion circuit 11. This process is
It is the same as the motion adaptive scan conversion circuit of an HDTV receiver.

After converting to progressive scanning, the YIQ/RGB converter 12
GBm number and displayed on display 13.

Here, progressive scanning display is considered, but in the case of interlaced scanning display, the scan conversion circuit [1] in FIG. 4 is not necessary.

In this method, as mentioned above, the resolution is lower than that of NTSC. If necessary, the resolution can be increased by multiplexing in one frequency domain. For example, field offset sampling, two-frame offset sampling, or multiplexing in the color signal area in the time-vertical frequency domain or in a position conjugate to the color signal in the time-vertical frequency domain (Japanese Patent Application Laid-open No. 171387-1987).
can be used.

Alternatively, the MUSE method used for satellite broadcasting of HDTV signals can also be applied.

Next, the wide TV reinforcement signal of the second stage of wide aspect TV will be described. First, the required information is (a) horizontal high-frequency luminance signal, two-color difference signal, (b) signal for progressive scanning conversion (line signal not transmitted as an interlaced scanning signal, or on the receiver side, There are various transmission methods, such as frequency division multiplexing, RF orthogonal modulation multiplexing, and digital transmission.

Of course, it is also possible to send a signal from only one side. Here, an example will be shown in which the CHI bandwidth is 6 MHz and RF orthogonal modulation multiplexing is used.

The spectrum at this time is as shown in FIG. Both bandwidths are 3 MHz, obtained by orthogonal modulation of RF.

An embodiment of the transmitter at this time is shown in FIG. 6, and the route for obtaining the wide aspect TV broadcast signal is the same as that in FIG. 3. The horizontal high-definition signal of the wide TV reinforcement signal has become a time-division component signal, so it is in the transport band 4, 5-7.
, 5 M Hyt BPF15 allows high-definition signal Y
By modulating fs (for example, 4.5 MHz with the modulator 16) with this high-definition signal,
Frequency shift the high-definition signal to DC, Y H' g C
o' Get the signal. On the other hand, the signal for progressive scan modulation twisting on the receiving side is converted into a YIQ signal by the RGB/YIQ converter 6, and then obtained by the scan conversion reinforcement signal generator 17.

This signal is passed through one time division multiplexing circuit 7 and converted into a time division component signal, and is passed through an LPF 18 with one pass band of 3 MHz to obtain an LD signal. By orthogonally modulating the RFI of the YHCH1 signal and LD signal with the 0M modulator 19,
Obtain wide TV reinforcement signal.

On the other hand, an embodiment of the receiver is shown in FIG.

The demodulation method for CH2 wide TV broadcasting is the same as that shown in FIG. The CHI reinforcement signal is provided by the tuner 21.

By orthogonal demodulation, it is separated into YH', CH' signals and LD signals.
In the m unit 16, the frequency is shifted by Is to produce a single high-definition YH.

The CH multiplied signal is demodulated. After that, it passes through a 5-hour expander 1° and is added to the low-frequency YIQ signal obtained from CH2 by an adder 20.
each added. On the other hand, the LD signal is similarly separated into Y, I, and Q signals by the time expander 10.

time is stretched. It is then sent to a scan converter 21, where the interpolated scan line is used as a reinforcement signal.

The above is based on Y, I, and Q signals, but NTS
In parts other than the C signal, signals Y, RY, and BY can also be used. It is also conceivable to transmit only the Y signal as the wide TV reinforcement signal.

〔Effect of the invention〕

The present invention employs a time-division analog component method. Therefore, the MA of satellite broadcasting in Europe
For studio equipment, the Y, R-Y, and B-Y component sampling standards have been adopted in the CClR601 recommendation. Although it is not compatible with current NTSC studio equipment, there is no problem considering that converters can be easily made and studio equipment also tends to be componentized.

In the second stage of introducing WireAspect TV, converters will be required for Qit line television receivers. However, since this converter only needs to change the current aspect and perform component/composite conversion, it can be implemented at a low cost.

[Brief explanation of the drawing]

FIG. 1 is a conceptual diagram illustrating the present invention in detail. Second
6 is a format diagram of a time-division component signal. FIGS. 3 and 4 are block diagrams of a transmitter and a receiver of a first stage wide aspect TV in an embodiment of the present invention. FIG. 5 is a spectrum diagram of one method of wide l'' in the embodiment of the second stage F,'l of the present invention, and FIGS. 6 and 7 are wide aspect TV signals of the embodiment of FIG. FIG. 2 is a block diagram of a transmitter and a receiver. ■...Sequential scanning wide 1゛■Camera, 2...Scan conversion circuit, 3...Aspect ratio conversion circuit, 4...N
TSC encoder circuit, 5...L P F", 6.
...ROB/YIQ conversion circuit, 7...Time division multiplex circuit, 8...LPF, 9...Tuner, 10...Time expansion circuit, 11...Scan conversion circuit, 12...YIQ
/RGB conversion circuit, 13...Display, 14...
・VSB-AM circuit, 15... BPF, 1B... Multiplier, 17... Scan conversion reinforcement signal generation circuit, 18 ・
L P F, 19-QM open circuit 2°...adder, 2
1...Tuner with orthogonal demodulation function. 1st mouth (αtsu Wight ass public Tocho Q, J tool 2 Kr present ff receiver / Y FTV receiver T (b)'Fito Ryos public Kuto Dyo V 2nd I2F'W present r
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Claims (1)

[Claims] 1. In a wide aspect television signal transmission system that is compatible with current television signals, the current television broadcasting is left as is, and another channel is used to transmit wide aspect television signals. signal,
A television signal transmission method characterized by transmitting luminance signals and color difference signals by time division multiplexing. 2. In the transmission system according to claim 1, after the simultaneous broadcasting system becomes widespread, the current television broadcasting is stopped and that channel or a channel whose bandwidth is halved is used, A television signal transmission method characterized by transmitting signals that improve the definition of wide aspect television.