KR0176630B1 - Signalless Channel Frequency Tuning Method - Google Patents

Abstract

[Technical field to which the invention described in the claims belong]

A method of tuning channel frequencies in a television's channel frequency tuning system.

[Technical Challenges to Invent]

This is to repeat the channel frequency tuning operation which is performed only once in the non-signal channel and ends.

[Summary of the solution of the invention]

According to the present invention, in the case where the channel frequency data corresponding to the establishment of the no-signal channel is not found among the signal frequencies of the multiple channels, the signal-free channel frequency tuning method is set subsequently after setting the no-signal channel flag and subsequently setting the channel. Subsequent channel frequency data corresponding to the channel are checked among the signal frequencies of multiple channels.

[Important Uses of the Invention]

When a no-signal channel is set, it can be removed to remove the wrong type of signal that appears on the screen of the television.After performing channel frequency tuning operation on the no-signal channel, even if another signal is inputted through the channel, the signal input can be removed. There is an advantage to see.

Description

Signalless Channel Frequency Tuning Method

1 is a block diagram of a general channel frequency tuning system.

2 is a flowchart of a conventional channel frequency tuning method.

3 is a flowchart of a channel frequency tuning method according to the present invention.

* Explanation of symbols for main parts of the drawings

110: Tuning control unit 120: Tuning control unit

130: tuner AT: antenna

The present invention relates to a method for tuning television channel frequencies, and more particularly, to a method for tuning a no signal channel frequency.

In general, televisions are applied with frequencies of various channels through an antenna. At this time, when the user selects a predetermined channel, the frequency corresponding to the selected channel is tuned and displayed on the screen of the television, and at the same time, audio is also output.

FIG. 1 shows a block configuration for the channel frequency tuning system of such a television.

Tuning operation unit 110 is composed of tuning operation button (0 ~ 9), power on / off button, volume control button and channel control button, etc., when a predetermined channel is selected by the user generates a corresponding key signal. The tuner 120 transmits channel frequency data (hereinafter referred to as PLL data) previously stored in response to the key signal generated from the tuner operator 110 to the tuner 130. The tuner 110, which is composed of a high frequency amplification circuit, a mixing circuit, and a local oscillation circuit, receives a plurality of channel frequencies through the antenna AT, and also receives PLL data transmitted from the international language controller 120. At this time, the tuner 110 checks the PLL data from the pre-international fish unit 120 and outputs the degree of distortion with respect to the actual channel frequency to the pre-international fish unit 120 as Automatic Frequency Control (FCC) voltage.

2 is a flowchart of a conventional channel frequency tuning method performed by the international language unit 120 of the channel frequency tuning system having the configuration as shown in FIG.

Referring to FIGS. 1 and 2, as the user presses a predetermined channel button on the channel selection unit 110, the international language unit 120 outputs PLL data corresponding to the channel selected by the user in step 200. . The tuner 130 analyzes the PLL data and outputs the degree of distortion as compared with the original channel frequency to the line controller 120 as the AFC voltage.

In step 210, the international fisherman 120 receives the AFC voltage and compares the received AFC voltage with a reference voltage (typically 2.65 volts) corresponding to the case where the received AFC voltage is tuned to the channel frequency in step 220. Determine the degree of distortion of the frequency. When the degree of distortion of the channel frequency is determined, in step 230, the international fisherman 120 calculates PLL data by one step. At this time, one-step operation of PLL data means adding or subtracting one-step frequency, for example, 62.5 kHz, to PLL data. If the AFC voltage is lower than the reference voltage, 62.5 ㎑ is added. If the AFC voltage is higher than the reference voltage, 62.5 ㎑ is subtracted.

In step 240, the international fisherman 120 checks whether the PLL data calculated in step 1 has reached the upper limit (channel frequency + 2 MHz) or the lower limit (channel frequency-MHz) of the channel frequency. By checking whether the PLL data calculated in step 1 has reached the upper or lower limit of the channel frequency, the user has pressed the signal channel in which the channel frequency of the television is set in the channel selection unit 110 or the channel frequency of the television is not set. You can check whether you have pressed an unsigned channel.

If the user presses the signal channel in which the channel frequency is set in the tuning operation unit 110, the process returns to step 200 to transmit the calculated PLL data to the tuner 130. Thereafter, the operations of steps 210, 220, and 230 as described above are repeatedly performed in the same manner. The repetitive operation is performed until the AFC voltage is confirmed to be equal to the reference voltage or the inversion of the AFC voltage with respect to the reference voltage is confirmed three times. Accordingly, the frequency of the signal channel selected by the user is tuned. Here, the reversal of the AFC voltage with respect to the reference voltage refers to a case where the AFC voltage level is larger than the reference voltage level. In this case, the pre-international fisherman 120 subtracts the PLL data by 62.5 ㎑ at step 230.

On the other hand, if the user presses the non-signal channel for which the channel frequency is not set in the tuning operation unit 110, the PLL data calculated in step 1 in step 240 reaches the upper or lower limit of the channel frequency. Will be confirmed. Next, the flow proceeds to step 250 to output the PLL data having reached the upper or lower limit of the channel frequency and terminates the channel frequency tuning operation.

As described above, in the non-signaled channel in which the channel frequency is not set, the channel frequency tuning operation is performed only once and ends. As a result, untuned PLL data output from the no-signal channel is maintained in the tuner, resulting in a distorted signal on a television screen.

In addition, after performing channel frequency tuning in the non-signal channel, even if another signal is input through the channel, the international language controller 120 cannot check the input of the signal.

Accordingly, an object of the present invention is to provide a method for tuning channel frequencies without distortion in the case where no signal channel is selected.

Another object of the present invention is to provide a method for tuning an unsigned channel frequency, in which it can be confirmed that the unsigned channel is selected again after the no-signal channel is selected.

It is still another object of the present invention to provide a method for tuning an unsigned channel frequency, in which a channel frequency tuning operation is repeatedly performed even when an unsignaled channel is selected.

According to the above objects, when the channel frequency data corresponding to the establishment of the no-signal channel is not confirmed among the signal frequencies of the multiple channels, the present invention is set subsequently after setting the no-signal channel flag and subsequently setting the channel. The present invention is directed to a signal-free channel frequency tuning method in which subsequent channel frequency data generated corresponding to channels are checked among signal frequencies of multiple channels.

In addition, the signal-free channel frequency tuning method according to the present invention, the channel frequency confirmation process for checking whether the channel frequency data is confirmed among the signal frequencies of the plurality of channels, and if the channel frequency data is not confirmed among the signal frequencies of the plurality of channels Proximity channel frequency range checking process to check whether the frequency data reaches the range of the signal frequency of the channel that is closest among the signal frequencies of the multiple channels, and when the channel frequency data reaches the range of the adjacent channel frequency, no signal channel flag Configure the flag setting process to set the.

DETAILED DESCRIPTION A detailed description of preferred embodiments of the present invention will now be described with reference to the accompanying drawings. Note that the following description corresponds to the case where a no-signal channel, for example channel 4, is set by the user.

3 shows a flow for a channel frequency tuning method according to the present invention.

Referring to FIGS. 1 and 3, when the user presses the channel button 4 on the channel selection unit 110, in step 300, the international language unit 120 confirms whether or not a signal-free channel flag is set (310). In step), the PLL data corresponding to channel 4 selected by the user is output. The tuner 130 analyzes the PLL data and outputs the degree of distortion as compared with the original channel frequency to the line controller 120 as the AFC voltage.

In step 320, the international fisherman 120 receives the AFC voltage, compares the received AFC voltage with a reference voltage corresponding to the case where the received AFC voltage is tuned with the channel frequency in step 330, and then determines the degree of distortion of the channel frequency. do. If the wrong degree of the channel frequency is determined, in step 340, the international fisherman 120 adds or subtracts 62.5 kHz, which is a frequency of one step, to the PLL data.

In step 350, the international fisherman 120 checks whether the PLL data calculated in step 1 has reached the upper or lower limit of the channel frequency. In this case, since the user presses the non-signaled channel 4 in which the channel frequency is not set in the channel selection unit 110, the PLL data calculated in step 1 in step 350 is the upper or lower limit of the channel frequency. You will see that you have reached. Next, the process proceeds to step 360 and ends after setting the no-signal channel flag.

Thereafter, when the user presses a predetermined channel button on the channel selection unit 110 again, the signalless channel flag is set in step 300, so the international language unit 120 performs steps 310, 320, and 330. The operations of steps 340 and 350 are repeatedly performed. This repetitive operation is performed until the AFC voltage is confirmed to be equal to the reference voltage or the inversion of the AFC voltage with respect to the reference voltage is confirmed three times. Accordingly, the frequency of the signal channel selected by the user is tuned.

As described above, when the no-signal channel is set, the operation of channel frequency tuning is repeatedly performed by setting the no-signal channel flag. As a result, the PLL data held in the tuner without being tuned in the no-signal channel can be removed to remove the erroneous signal shown on the television screen. In addition, after performing channel frequency tuning on the non-signal channel, there is an advantage that the input of the signal can be confirmed even if another signal is input through the channel.

Claims (6)

Operation means for channel setting, control means for outputting channel frequency data in response to a channel signal generated corresponding to the channel set by the operation means, receiving signal frequencies of a plurality of channels and the channel frequency data being received A tuning method of a channel frequency tuning system, comprising tuning means for outputting a control voltage indicating a degree of approaching signal frequencies of a plurality of channels to said control means, said channel frequency data responsive to a channel signal generated by said operating means. If is not confirmed among the signal frequencies of the plurality of channels, after setting the no-signal channel flag, the subsequent channel frequency data generated corresponding to the subsequently set channel is generated even if the channel is subsequently set by the operation means. Nothing characterized by checking in frequency No. channel frequency tuning method. Operation means for channel setting, control means for outputting channel frequency data in response to a channel signal generated corresponding to the channel set by the operation means, receiving signal frequencies of a plurality of channels and the channel frequency data being received A tuning method of a channel frequency tuning system comprising tuning means for outputting to said control means a control voltage indicative of proximity to signal frequencies of a plurality of channels, wherein the channel frequency data is identified among the signal frequencies of the plurality of channels. A channel frequency checking process for checking whether or not the channel frequency data reaches a range of signal frequencies of an optimally closest channel among the signal frequencies of the plurality of channels when the channel frequency data is not found among the signal frequencies of the plurality of channels. Proximity channel frequency range to determine whether And a flag setting process of setting a no-signal channel flag when the channel frequency data reaches the range of the adjacent channel frequency. The method according to claim 2, wherein after the non-signal channel flag is set, even if a channel is subsequently set by the operation means, subsequent channel frequency data generated corresponding to the subsequently set channel are present in the signal frequencies of the plurality of channels. And a non-signaling channel frequency tuning method for repeating the channel frequency checking process to confirm. 4. The method of claim 3, wherein the checking of the channel frequency comprises increasing stepwise the size of the channel frequency data to determine whether the channel frequency data or the subsequent channel frequency data exist within the signal frequencies of the plurality of channels received by the control means. Signal-free channel frequency tuning method characterized in that while checking. The method of claim 3, wherein the checking of the channel frequency comprises: a control voltage indicating a degree to which the channel frequency data or the subsequent channel frequency data is close to the received signal frequencies of the plurality of channels. Comparing the voltage with a reference voltage indicating whether frequency data exists at the signal frequencies of the received multiple channels; and stepping the magnitude of the channel frequency data or the subsequent channel frequency data when the control voltage and the reference voltage are different. No signal channel frequency tuning method, characterized in that consisting of the process of increasing the channel frequency data size to increase. The method of claim 3, wherein the determining of the proximity channel frequency range comprises: when the channel frequency data or the subsequent channel frequency data is not found among the signal frequencies of the plurality of channels, the channel frequency data or the subsequent channel frequency data is the majority. A signal-free channel frequency tuning method characterized by checking whether the upper or lower limit of the signal frequency of the channel closest to the optimal signal frequency of the channel is reached.