KR20000034734A - Method for classifying automatic channel for tv - Google Patents

Abstract

PURPOSE: A method for classifying automatic channel for TV is provided so that user's convenience become increased by classifying channels using a frequency table at the auto tuning system(ATS). CONSTITUTION: A method for classifying automatic channel for TV includes a step for obtaining the difference(I) between the first PLL data value and the last PLL data value (507S) by obtaining the PLL data value of a reference channel (m), jumping to the next channel, searching for a normal tuning point, and storing the PLL data at the normal tuning point. A step is to obtain the difference(I') between the first PLL data value and the last PLL data value (512S) by storing PLL data value of a reference channel (n), jumping to the next channel n of the same broadcasting signal, and tuning the corresponding channel.

Description

TV automatic channel classification method

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a TV system, and more particularly, to an automatic channel classification method of a TV that improves user convenience by performing channel classification using a frequency table in an ATS mode.

One of the functions generally used in TV systems is the Automatic Tuning System (ATS).

The ATS function is one of the basic functions used in a TV system. The ATS function automatically tunes a channel using an ATS code assigned to each broadcasting station.

Broadcasting stations that do not implement the ATS function have also registered the ATS code in the broadcasting associations of the region.

Hereinafter, a TV system according to the related art will be described with reference to the accompanying drawings.

1 is a schematic configuration diagram of a TV system of the prior art.

A schematic configuration of a TV system of the prior art is first composed of a TV system control unit 3 which controls the entire TV system and outputs a TV broadcast signal on the screen, and a TV body configured to receive a user's selection signal. The external input signal processor 4 for processing, the OSD unit 5 for outputting an OSD (On Screen Display) signal under the control of the TV system controller 3, and the tuning control signal of the TV system controller 3 A tuner unit 1 for selectively outputting a broadcast signal, a TV image processor 2 for receiving and outputting TV image data and OSD data of the tuner unit 1, and outputting the image data to the TV image processor 2 It is largely comprised of the external display part 6 which displays an output signal to the exterior.

The TV system configured as described above is controlled by the TV system control unit 3 which controls the whole of the TV system. When the user inputs a control signal such as TV o / off and channel selection, the user inputs a selection control signal using a remote controller. The external input signal processing unit 4 processes this, and the TV image data selected by the tuner unit 1 and the OSD data of the OSD unit 5 are processed by the TV image processing unit 2 according to the processed signal. Displayed in section 6.

In such a TV system, various services have been attempted using various information including broadcast information transmitted between program signals.

The reception block of such information data will be described below.

2 is a schematic configuration diagram of a TV system centered on a reception block of broadcast information data.

Broadcasting methods using broadcast information data may be classified into a VPS (Video Programmable System) and a PDC (Program Delivery Code).

The VPS transmits broadcast program information data on a 16th line existing on an equalized pulse section that does not appear on the screen among broadcast signals, and receives the VPS signal from a receiver (TV / VCR). It is possible to recognize the information of the broadcast signal being received.

In addition, the PDC is developed and used in Europe, such as Germany, the United Kingdom, Australia, and the difference from the VPS transmits the Teletext information data, and similarly, the teletext data information is loaded on the equalization pulse section. To give.

2 illustrates a block related to performance of an ATS mode using broadcast information data. The microcomputer 20 controls a TV function and data of a corresponding signal according to a preset mode of an input signal. PDC / VPS decoder 22 for storing the data in the microcomputer 20 or reading from the microcomputer 20, and receiving the tuning data from the microcomputer 20 and received through the antenna ANT. Tuner 21 for tuning to any one of the broadcast radio waves and applying the video signal formed at that time to the PDC / VPS decoder 22, and the tuning data of the program, and the microcomputer 20 when the program is changed. The memory unit 23 stores the data so that the data can be read.

The PDC / VPS data detection operation in the TV system configured as described above is as follows.

In an ATS (Auto Tuning System) operation using PDC / VPS data in a TV system, the microcomputer 20 applies the data to the tuner 21 while gradually increasing its value from the lowest value of the tuning data.

The tuner 21 receives data from the microcomputer 20 and tunes the corresponding frequency, and sends the video signal formed at this time to the PDC / VPS decoder 22 through a data transmission line. AFT data is output to the microcomputer 20.

The PDC / VPS decoder 22 detects PDC / VPS data from a video signal input from the tuner 21 and stores the PDC / VPS data in an internal register so that the PDC / VPS decoder 22 can read at any time from the microcomputer 20. Make

In addition, the microcomputer 20 has the H-syncnose and AFT data of the input video, controls the value of the tuning data, and finds the right tuning point of the received broadcast.

Such a TV system performs various functions by using information data transmitted between video signals.

The most representative of these is the ATS function.

Channel classification in such a TV system is as follows.

After ATS operation, the signal strength was divided into IF AGC (Auto Gain Control) or RF AGC when classifying the strong signal / weak signal and selecting the strong signal among the channels of the same code.

When looking at a field signal, only one channel is required, but since only one channel signal is scattered, only one strong signal should be selected at the time of channel classification. When using IF or RF AGC, the signal strength is as shown in FIGS. 3A and 3B.

3A and 3B are graphs showing AGC signal strengths according to channel classification of the prior art.

When the signal strength is determined using the IF / RF AGC of the corresponding channel among the ATSs input to the A / D converter of the microcomputer, the signal strength appears smoothly as shown in ① of FIG. 3A and ② of FIG. 3B.

This means that ATS classification is not fine.

Such a conventional TV system has the following problems.

In the conventional TV system, when signals of the same station name are detected during automatic channel selection, the signal having the best reception state is used for channel classification, or when the signal of the same station name is detected, IF / RF AGC of the corresponding channel is detected. It was not possible to distinguish the signal strength by discriminating it.

Therefore, it is inefficient and inconvenient to the user in terms of device operation because accurate channel classification is not performed.

The present invention has been made to solve the problems of the conventional TV system, and provides a TV automatic channel classification method for improving user convenience by performing channel classification using a frequency table in the ATS mode. There is a purpose.

1 is a schematic configuration diagram of a conventional TV system

2 is a schematic configuration diagram of a TV system centered on a reception block of broadcast information data;

3A and 3B are graphs showing AGC signal strengths according to channel classification according to the prior art.

4 is a graph illustrating a search operation in channel classification according to the present invention.

5 is a flowchart illustrating an automatic channel classification method according to the present invention.

The present invention obtains the PLL data value of the reference channel (m), jumps to the next channel to find the right tuning point, stores the PLL data_ 'in this state, and stores the PLL data value' and the final PLL data value ''. The difference (I) is calculated, the PLL data value is set to 점프, the jump is made to another CH n of the same broadcast signal, and the PLL data value is stored as ㉯ 'while the corresponding channel is tuned. It is characterized in that the channel classification is performed using the difference I 'of the PLL data value ㉯'.

Hereinafter, with reference to the accompanying drawings will be described in detail with respect to the automatic channel classification method of the TV according to the present invention.

4 is a graph illustrating a search operation during channel classification according to the present invention, and FIG. 5 is a flowchart illustrating an automatic channel classification method according to the present invention.

The present invention relates to a method of classifying a channel by using a distorted degree value of a frequency table rather than by a strong signal or a weak signal when classifying a channel.

First, the PLL data is jumped to the channel next to CH 3 in the same manner as in ㉮ (the PLL data value of the reference channel) in Fig. 4A. (501S)

Then, it is determined whether there is a sync on the corresponding channel (502S), and it is determined whether there is a window (503S).

Subsequently, if there is a sync and a window, it is determined whether it is a right tuning point (504S).

If it is not the forward tuning point, the tuner PLL value is increased / decreased to determine whether the sync and the window exist again to find the forward tuning point (505S).

At this time, the step size is set to 500KHz for sync detection and 100KHz for window detection. The tuning point is 62.25 KHz.

If the right tuning point is found, the PLL data_ 'is stored while tuning the channel to CH3 as shown in FIG. 4B (506S).

Then, the difference I between the first PLL data value 최종 and the last PLL data value 의 'of the reference channel is calculated (507S).

In this way, the PLL data is jumped to CH 25 through the ATS process of the intermediate channel (when there is no broadcast signal identical to CH 3 in the intermediate ATS process), as shown in FIG. 4C.

Then, it is determined whether there is a sync on the corresponding channel (509S), and whether there is a window (510S).

Subsequently, if there is a sync and a window, the PLL data value is stored as '' with CH 25 tuned (511S).

The difference (I ') between the first PLL data value 의 and the final PLL data value ㉯' of CH 25 is calculated (512S).

Subsequently, the channel is classified after the calculation of the distance from the frequency table value of the reference channel is completed for all the channels (513S).

After the channel classification, the ATS code of CH 3 is compared with the ATS code of CH 25 (514S).

In this case, if the two values are the same, the same channel is compared, and the magnitudes of the I value and the I 'value are compared.

If I 'is large, it is a different channel, so store each channel. If not, store CH 3 and delete CH 25 (516S).

As described above, the present invention classifies a channel by using a wrong value of a frequency table, not by a strong signal or a weak signal.

According to the automatic channel classification method of the TV according to the present invention, when signals of the same broadcasting station name are detected, the channels are classified by using the corrected values of the frequency table in order to use the signal having the best reception state among them for channel classification. The channel classification is performed to increase the efficiency in terms of device operation, which increases the user's convenience.

Claims (1)

In the method of performing the ATS mode of the TV system, Obtaining a PLL data value 의 of the reference channel m and jumping to a channel next to CH m to determine whether there is Sync and a window in the corresponding channel; Increasing / decreasing the tuner PLL value until there is a right tuning point if there is a sync and a window; If the right tuning point is found, storing the PLL data_ 'and calculating the difference (I) between the first PLL data-value and the last PLL data-value' 'with CH m tuned; Determining whether there is a sync and a window in the corresponding channel by jumping to CH n with the PLL data value as the Z through the ATS process of the intermediate channel; If there is a sync and a window, storing the PLL data value as' 'while tuning CH n and obtaining a difference I' between the first PLL data value and the last PLL data value ''; Performing channel classification and comparing the ATS code of CH m and the ATS code of CH n and comparing the magnitudes of I values and I ′ values when the two values are the same; If the value of I 'is a different channel, the channel is stored separately, and if not, the channel CH, characterized in that it comprises the step of storing the CH m and deleting the CH n.