KR100617830B1 - Apparatus for tuning channel automatic in television phone and method thereof - Google Patents

Abstract

The present invention relates to a channel automatic tuning apparatus for a television phone and a method for automatically tuning a local channel of a television. The channel automatic tuning device includes: a bandpass filter for filtering only a signal of a TV band among propagated signals; A TV unit connected to the bandpass filter and demodulating and outputting a video signal and an audio signal by selecting a broadcast channel corresponding to a channel tuning control signal, and detecting and outputting a video signal level or a noise level of the video signal of the selected channel; ; An MRFU for receiving and demodulating and receiving an incoming signal of a forward channel for forming a voice call channel among the received radio signals, and modulating and transmitting a signal of a reverse channel; The phone mode / TV mode is set in response to an input command, and the channel control signal is generated by the setting of the TV mode, and when the video signal level or the video signal noise level is lower than a preset reference level, A MSP for selecting one of the corresponding other regional channel selection signals to provide to the TV unit and disabling the TV unit when an incoming signal is output from the MRFU and processing a signal accessed from the MRFU; It is composed.

 TV phone, auto tuning, local channel information,

Description

Channel automatic tuning device for television phones and control method thereof {APPARATUS FOR TUNING CHANNEL AUTOMATIC IN TELEVISION PHONE AND METHOD THEREOF}             

1 is a block diagram of a television telephone according to an embodiment of the present invention;

Fig. 2 is a flow chart of channel automatic switching control of a television telephone according to an embodiment of the present invention.

3 shows a television channel information memory table according to an embodiment of the invention;

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a television mobile telephone (hereinafter referred to as a "TV phone"), and more particularly, to a channel automatic tuning device for a TV phone that automatically maintains the same broadcast channel even when a region is moved, and a control method thereof. will be.

With the rapid spread of portable telephones, various functions have been developed in addition to simple telephone functions according to the needs of consumers. For example, a calculator function, a biorhythm check function, and a TV, a video camera, and a function for transmitting and receiving images are being developed. Here, the term "TV phone" refers to a portable mobile radio telephone in which a TV broadcast program can be viewed using a display device of a cellular phone in addition to a mobile communication telephone function.

For the TV broadcast reception function as described above, at least two radio frequency units must be present in the mobile phone. The reason for this is that the frequency bands necessary for transmitting and receiving unique messages (voice and data) of the mobile phone and the frequency band of the TV broadcast are different from each other, and the operation mode is also largely in the phone mode, the waiting mode, and the above. The TV mode is divided into a standby mode and a video receiving mode.

In addition, since the TV phone must use a liquid crystal display (LCD) or a thin film transistor (TFT), a speaker, or an earphone, which is a display device of a mobile phone, to display the screen and sound of a television broadcast received in the TV mode, respectively. The method of notifying the user of the incoming call and the text message should be different from the general mobile phone. This is because there is no way to notify the user immediately when an incoming call or a text data message is received while the screen and the voice of the broadcast program selected by the display device and the speaker of the cellular phone are respectively output. Therefore, it can be seen that such a TV phone requires a new function for informing the user of the incoming call and the receipt of the text data more quickly and accurately in the TV mode.

For example, the TV phone having the above function is disclosed in Korean Patent Application No. 98-56487, which was developed by the applicant of the present application and patented on December 19, 1998. However, since a typical TV phone is carried by a user and moves around the area, the channel must be changed relatively frequently. This is because channel values of the same broadcasting station are set differently according to regions. Therefore, when the TV phone is moved out of the broadcast zone while watching a program of a specific broadcast station, inconveniences of manually tuning the TV channel to the channel of the broadcast zone occurs.

For example, moving to the Chungcheong area while watching a program of KBC broadcasting station using a TV phone in the Seoul area, the inconvenience of having to re-channel selection to the KBC broadcasting channel value of the Chungcheong area.

Accordingly, an object of the present invention is to provide a TV phone and a method of controlling the same so that the user can watch the same broadcast program by automatically switching to a channel of the corresponding broadcast area when leaving the broadcast area.

Another object of the present invention is to provide a TV phone and a control method for automatically searching for and switching a corresponding broadcast channel by detecting a noise level of a received video signal and / or electric field strength of a received signal.

The present invention for achieving the above object is a band pass filter for filtering only the signal of the TV band of the propagated signal; A TV unit connected to the band pass filter and demodulating and outputting a video signal and an audio signal by selecting a broadcast channel corresponding to a channel tuning control signal, and detecting and outputting a video signal level or a noise level of the video signal of the selected channel. Wow; A mobile station radio frequency unit (MRFU) for receiving demodulated and outputting an incoming signal of a forward channel for forming a voice call channel among the received radio signals, and modulating and transmitting a signal of a reverse channel; The phone mode / TV mode is set in response to an input command, and the channel control signal is generated by the setting of the TV mode, and when the video signal level or the video signal noise level is lower than a preset reference level, MSP (mobile station) which selects one of the corresponding local channel tuning signals to provide to the TV unit, and disables the TV unit when the incoming signal is output from the MRFU and processes the signal accessed from the MRFU. and a processor).

In accordance with an aspect of the present invention, a method for automatically switching channels of a television telephone includes: detecting a video signal level or a noise level of a video signal of a selected channel; Searching for the information area of the currently selected channel in response to the level being lower than the level; and increasing the address pointer of the searched information area to provide an international language signal of another region to the TV unit. It features.

Hereinafter, a channel automatic tuning apparatus and a control method for a television telephone according to a preferred embodiment of the present invention will be described with reference to the accompanying drawings. In the following description, detailed items for such a configuration provide a more thorough understanding of the present invention. It is explained in detail for that. However, it will be apparent to those skilled in the art that the present invention may be practiced without these specific details.

1 is a block diagram of a television telephone according to an embodiment of the present invention. Referring to FIG. 1, an output of a band pass filter (BPF) 14 that filters only signals of a TV band among radio signals received through an antenna 12 is connected to an input of a TV unit 16. The TV unit 16 demodulates and outputs a video signal and an audio signal by selecting only a signal of a corresponding broadcast channel among signals received through the band pass filter 14 in response to a channel tuning control signal input from the outside. And a level / noise detector 24 for detecting and outputting the video signal level or the noise level of the video signal. In addition, the MRFU 18 receives and demodulates and outputs an incoming signal of a forward channel for forming a voice call channel among radio signals received through the antenna 12, and modulates and transmits a signal of a reverse channel. The MSP 20 sets the phone mode / TV mode in response to a command input through the bus 30, and provides an international language signal to the TV unit 16 by setting the TV mode. When one of the video signal level or the video signal noise level output from 16) is lower than a preset reference level, one of the other channel channel selection signals corresponding to the current selection channel is selected and provided to the TV unit 16. When the incoming signal is output from the MRFU 18, the TV unit 16 is disabled and the signal accessed from the MRFU 18 is processed. In addition, the display unit 22 connected to the TV unit 16 and the MSP 20 displays an image signal output from the TV unit 16 or displays a text message outputted from the MSP 20 by OSD (on). screen display). According to the above configuration, while watching a TV program of a specific broadcasting station by setting the TV phone to a TV mode, even if the user moves out of a broadcasting area of a corresponding region to another region, the specific broadcasting program can be watched seamlessly in the moved other region. .

The MSP 20 used above has a microprocessor, video codec, and the like embedded therein, and an MSM chip series currently manufactured by Qualcomm may be used.

2 is a flowchart illustrating a channel automatic switching control of a television telephone according to an embodiment of the present invention. This control flow is program masked to a ROM located in the MSP 20 shown in FIG. 1, the detailed control process of which is described in detail below.

FIG. 3 is a diagram illustrating a television channel information memory table according to an embodiment of the present invention, wherein a memory area in the MSP 20 shown in FIG. 1, for example, a volatile area such as RAM or EEPRM Tableed and stored in the same nonvolatile area.

First, the channel information memory table will be described with reference to FIG. 3. The channel information memory table according to the present invention has a plurality of broadcast channel areas A1, A2 and A3 divided based on broadcast stations. For example, the KBC broadcasting station is set so as to correspond to the broadcasting channel area A1, the KBN broadcasting station corresponds to the broadcasting channel area A2, and the MBS broadcasting station corresponds to the broadcasting channel area A3. In the above description, each of the broadcast channel regions A1, A2, and A3 includes a plurality of local channel regions SPi (where i is a natural number such as 1, 2, 3 ,,, etc.), and each of the local channel regions SPi is internal. The local channel information of the broadcasting station is stored. That is, the channel selection information of the Seoul area is stored in the local channel area SP1 in the broadcasting channel area A1 of the KBC broadcasting channel, the channel selection information of the Daejeon area is stored in SP2, and the channel selection information of the Busan area is stored in SP3. Therefore, when a broadcasting station is out of a state in which a channel of any broadcasting station is tuned and a program of the broadcasting station is being watched, the channel being watched by sequentially accessing information in the local area SPi in the broadcasting channel area is performed automatically. We can watch program of regardless of area continuously. This will be understood in more detail by the following detailed description.

Now, the operation mode of the TV phone shown in FIG. 1 is set to the TV mode so that the TV unit 16 filters the band by the BPS 14. Assuming that a particular channel of TV broadcasting frequencies, for example, a demodulating signal of a Seoul area broadcast signal of a KBC broadcasting station, is received and outputted to a line 26 and a display unit 22, outputs an audio signal and a video signal. At this time, the TV unit 16 performs operations such as on / off and channel selection in accordance with the control signal CTLB provided from the MSP 20. Inside the TV unit 16 operated as described above, a detector 24 for measuring the level of the video signal of the tuned channel or the noise level included in the video signal or the received field strength of the tuned channel signal is provided. The output of the detector 24 is provided to the MSP 20.

In the state in which the TV phone shown in FIG. 1 is operated as described above, in the state of viewing the video signal displayed through the display unit 22 of the TV phone, the MSP 20 selects the channel of the TV in the sequence shown in FIG. To control. For example, when the user sets the TV mode to the mode of the TV phone using a key on a keypad (not shown), the international language signal for selecting a channel previously selected in step 32 is output as CTLB, In step 34, the signal input to the bus line 30 is read to search whether the channel CH signal is input.

If it is determined that the channel selection signal is input in step 34, the MSP 20 provides the TV unit 16 with an international language signal for tuning the channel in step 36 as the CTLB. At this time, the TV unit 16 performs a tuning operation in response to the pre-international language signal to select and demodulate a corresponding channel frequency among a plurality of channels.

However, if it is determined in step 34 that the channel selection signal is not the MSP 20, the MSP 20 outputs a signal indicating the video signal level or the video signal noise level or the received electric field strength output from the detector 24 in the TV unit 16 in step 38. Check it. In operation 40, the MSP 20 compares the input video signal level, the video signal noise level, or the received electric field strength with a reference value preset in the internal memory area.

For example, when the detection signal output from the detector 24 in the TV unit 16 is a video signal level or an electric field strength signal, the MSP 20 sets a reference video signal level or reference electric field strength preset in an internal memory area. If it is lower than the reference video signal level or the reference electric field strength compared to the signal, steps 42 and 44 to be described later are performed to automatically tune with local channel information of the previously selected broadcast station. If the noise level of the video signal is higher than the reference noise level preset in the internal memory area, if the reference noise level is higher than the reference noise level, steps 42 and 44 described below are performed automatically with the local channel information of the previously selected broadcasting station. The tuning operation is performed.

The MSP 20 performing the process 42 of FIG. 2 searches for a broadcast channel region corresponding to a broadcast station previously tuned in the channel information memory table shown in FIG. For example, when the channel information previously viewed is CH-INFO1, the broadcast channel area is found as "A1". This operation is easily performed by scanning the contents of the channel information memory table. Thereafter, the local channel area SPi in the broadcast channel area A1 is searched to find next information of previous channel information. For example, since the channel information previously viewed is CH-INFO1, the MSP 20 searches for channel information CH-INFO2 stored in the next area of CH-INFO1 and outputs the found information. In the process, the address pointer is increased to provide a channel tuning control signal for selecting the corresponding channel information to the TV unit 16 shown in FIG.

The TV unit 16 is a signal of a channel corresponding to the channel selection language signal among the signals of the TV band output from the band pass filter 14 in response to the input of the channel selection control signal output from the MSP 20. To demodulate and output the video signal of the local channel of the specific broadcasting station previously watched. At this time, the detector 24 in the TV unit 16 detects and outputs the level or noise level of the demodulated video signal or the received electric field strength as described above, and the MSP 20 repeats operation from step 34 of FIG. Do this.

Therefore, according to the embodiment described above, even when the video signal of a specific broadcasting station having a different channel frequency in each region is received in a certain region and moved to another region, the TV can be continuously watched by automatically switching to the channel of the region.

As described above, the present invention is more convenient for watching TV using a TV phone by automatically searching for a local channel of a specific broadcast station and automatically switching channels even though the user moves to another area while watching a program of a specific broadcast station on the TV phone. It can be done.

Claims (7)

A channel automatic tuning device for a television telephone, A band pass filter for filtering only a signal of a TV band among propagated signals; A TV unit connected to the bandpass filter and demodulating and outputting a video signal and an audio signal by selecting a broadcast channel corresponding to a channel tuning control signal, and detecting and outputting a decrease in reception sensitivity of the video signal of the selected channel; MRFU which receives and demodulates the incoming signal of the forward channel to form a voice call channel among the received radio signals, modulates the reverse channel signal, and transmits it; Set a phone mode / TV mode in response to an input command and generate the channel control signal by setting the TV mode, and when the video signal reception sensitivity is lower than a preset reference reception sensitivity, the other corresponding to the current selection channel. Selecting one of the local channel selection signal to provide to the TV unit, and comprises a mobile international controller for disabling the TV unit when processing the incoming signal from the MRFU and processing the signal accessed from the MRFU A channel automatic tuning device for a television telephone. The channel of claim 1, wherein the TV unit includes a detector for detecting a level of a video signal or a noise level of a video signal and an electric field strength of a received video signal and outputting the received signal as a reception sensitivity signal. Automatic tuning device. 3. The apparatus of claim 2, wherein the reference reception sensitivity preset in the mobile station controller is a reference video signal level or reference field strength. 3. The channel automatic tuning device for a television telephone according to claim 2, wherein the reference reception sensitivity preset in said mobile station controller is reference video signal noise for detecting an amount of noise of the video signal. The channel automatic tuning device for a television telephone according to any one of claims 1 to 4, further comprising a display unit for displaying a video signal output from the TV unit and a text message output from the mobile station controller. . In the channel automatic switching control method of a television telephone having local broadcasting channel information of each broadcasting station, Measuring a reception sensitivity of an image signal received through a selected channel; Searching for an information region of a currently selected channel in response to a deviation from a preset error range by comparing the measured sensitivity of the video signal with a preset reference sensitivity value; And increasing the address pointer of the searched information area to provide an international signal of another region of the currently selected channel to the TV unit. In the channel automatic switching control method of a television telephone, Detecting a video signal level or a noise level of the video signal received through the selected channel; Searching for the information area of the currently selected channel in response to the detected video signal level or the noise level of the video signal being lower than a preset reference level; And increasing the address pointer of the searched information area to provide an international signal of another region of the currently selected channel to the TV unit.

Images