KR20000039386A - Method for tracking channel of digital satellite broadcast receiver - Google Patents

Abstract

PURPOSE: A method for tracking a channel of a satellite broadcast receiver is provided to reduce auto-scanning time and tracking time by quickly performing tracking on each channel of a digital satellite broadcast by using a previously stored offset. CONSTITUTION: In a method for tracking a channel of a satellite broadcast receiver, the first step is to read a previously stored offset corresponding to an input channel when a channel selection signal is inputted. When the tracking is performed by applying a predetermined sweep range, the offset on the center frequency is stored by each channel. The second step is to compensate a center frequency on the selected channel by using the offset and then perform tracking by using the compensated center frequency. When the tracking is not performed, the tracking is performed by applying the sweep range.

Description

Channel Tracking Method of Digital Satellite Broadcasting Receiver

The present invention relates to a channel tracking method of a digital satellite broadcasting receiver. In particular, the tracking of each channel of the digital satellite broadcasting can be performed quickly using a previously stored offset, so that the tracking time is shortened and the auto scan is required. The present invention relates to a channel tracking method of a digital satellite broadcast receiver with a reduced time.

In general, there are more than a few dozen satellites for digital satellite broadcasting, and each satellite signal transmitted from each satellite includes a plurality of transponders, each transponder having a frequency information, a transmission speed and a frequency band. Content such as symbol-rate including information about, code rate including information about coding scheme, polarization including information about signal type such as signal convenience, etc. It includes.

Each of the transponders includes a plurality of channels. In order to receive one channel in a specific transponder, tracking to the corresponding channel should be performed.

In the conventional tracking method, since the center frequency of a channel may be changed during the transmission process, the tracking is attempted at a center frequency for a specific channel first, and when the tracking is not performed normally, the center is set to a predetermined sweep range. The tracking is attempted again by compensating for the frequency fc, which will be described in more detail with reference to FIG. 2. First, attempting the tracking at the center frequency fc, and if no tracking is performed, the center frequency ( fc) is a frequency fc + fs that compensates for the positive compensation frequency (+ fs) of the sweep range, and then the frequency is attempted to fc-fs, fc + 2fs, fc-2fs, and so on.

However, such a conventional channel tracking method has a problem in that it takes a long time to perform the tracking because the channel is started from the center frequency for each channel to perform the tracking according to the above-described method.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems. Accordingly, an object of the present invention is to shorten the tracking time by quickly performing tracking for each channel of digital satellite broadcasting using a previously stored offset. At the same time, the present invention provides a channel tracking method of a digital satellite broadcasting receiver which reduces the time required for auto scanning.

1 is a block diagram of a digital satellite broadcast receiver for carrying out the present invention.

2 is a tracking frequency diagram for explaining a conventional channel tracking method.

3 is a flowchart for storing offset for each channel for channel tracking of the digital satellite broadcast receiver according to the present invention.

4 is a flowchart showing a channel tracking method of a digital satellite broadcasting receiver according to the present invention.

Explanation of symbols on the main parts of the drawings

10 control unit 11 channel section

12: demultiplexer 13: video / audio decoder

14: video encoder 15: audio D / A converter

As a technical means for achieving the above object of the present invention, the method of the present invention is a channel tracking method of a digital satellite broadcasting receiver, when the channel selection is input, reading the previously stored offset corresponding to the input channel; Stage 1; And a second step of performing tracking at the corrected frequency after correcting the center frequency of the selected channel with an offset.

Hereinafter, a digital satellite broadcast receiver for carrying out the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram of a digital satellite broadcast receiver for carrying out the present invention. Referring to FIG. 1, a digital satellite broadcast receiver for carrying out the present invention controls each unit according to a key input such as channel selection not shown. A control unit 10, a channel unit 11 for performing a tuning process, a demodulation process, an A / D conversion, and a channel decoding process under control of the control unit 10, and video and audio from the channel unit 11; A demultiplexer (12) for separating signals, a video / audio decoder (13) for decoding video and audio signals from the demultiplexer (12), and a video signal from the video / audio decoder (13). A video encoder 14 for converting into a signal and an audio D / A converting section 15 for converting a digital audio signal into an analog audio signal.

3 is a flowchart for storing channel offsets for channel tracking of a digital satellite broadcast receiver according to the present invention, and FIG. 4 is a flowchart showing a channel tracking method of the digital satellite broadcast receiver according to the present invention.

Operation according to the present invention configured as described above will be described in detail below based on the accompanying drawings.

Referring to FIG. 1, FIG. 3, and FIG. 4, first, in order to perform channel tracking in the digital satellite broadcasting receiver according to the present invention, as shown in FIG. In the following description, first, a satellite signal received through a satellite antenna (ANT) is received by the channel unit 11 to perform tracking for a channel set in a corresponding transponder under the control of the controller 10. As in steps 31 and 32 of FIG. 3, if the tracking is not performed in step 33 and the tracking is not performed in step 33, the center frequency fc is applied by applying a sweep range determined through steps 34 to 40. Compensate the center frequency with the up and down frequency by + fs, -fs, + 2fs, -2fs, etc., and perform the tracking by storing the offset in correspondence with the corresponding channel.

As described above, the channel tracking method of the digital satellite broadcasting receiver according to the present invention in the state where the corresponding offset for each channel is stored will be described with reference to FIG. 4. First, in the first steps 51 and 52, the channel selection is performed by the controller 10. When is input, the previously stored offset corresponding to the input channel is read.

In the second step 53, the center frequency fc of the selected channel is corrected to an offset and tracking is performed at the corrected frequency.

As described above, in the case of performing channel tracking by applying an offset, a quick channel tracking is performed by accurate tracking without the operation described in the offset storing process. If the degree tracking is not performed, the tracking is performed again by applying the sweep range as described above based on the center frequency corrected by the offset.

On the other hand, according to the present invention, in the channel tracking with the offset applied, by irradiating the symbleb of the transponder to perform the fasting from the low symblet to enable faster fasting.

According to the present invention as described above, by performing the tracking for each channel of the digital satellite broadcasting using a pre-stored offset, the special effect of shortening the tracking time and at the same time the auto scan time is reduced It is.

The above description is only a description of one embodiment of the present invention, the present invention is capable of various changes and modifications within the scope of the configuration.

Claims (3)

In the channel tracking method of a digital satellite broadcasting receiver, A first step of reading a previously stored offset corresponding to the input channel when the channel selection is input; And a second step of performing tracking at the corrected frequency after correcting the center frequency of the selected channel with an offset. 2. The method of claim 1, wherein the offset storing method referred to in the first step is performed when the tracking is performed by applying a predetermined sweep range to store the offset for the center frequency for each channel. Channel tracking method of digital satellite broadcasting receiver. The channel tracking of the digital satellite broadcasting receiver as claimed in claim 1, wherein the second step determines whether or not the tracking is performed, and when the tracking is not performed, the channel tracking is performed by applying a sweep range. Way.