KR20060014105A - Wireless video transmit apparatus - Google Patents

Abstract

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless video transmission apparatus that maintains an optimal transmission rate by changing a channel according to a communication state in transmission of video and audio signals between a transmitter and a receiver. Search for a channel having an optimal data rate, or wirelessly transmit input video / audio data to a set frequency channel, and apply video / audio data to one of the two WLAN cards to instruct transmission. A transmitter having an MCU which checks a data rate and outputs video / audio data to the WLAN when an optimal channel is set after instructing channel discovery to another WLAN card when the data rate is lowered below a reference value; And two WLAN cards respectively searching for a plurality of frequency channels in the WLAN frequency band and searching for a channel for an optimal transmission rate, or receiving wireless signals transmitted from the transmitter through a set frequency channel and restoring video / audio data. Instructs one of the WLAN cards to receive data and checks the data rate. When the data rate falls below the threshold, the other WLAN card is instructed to search for a channel. It consists of a receiver having an MCU for changing the reception.

Set Top Box, Wireless Video Transmission, WLAN Card, Channel, Baud Rate

Description

Wireless video transmit apparatus

1 is a block diagram showing a conventional wireless image transmission device.

2 is a block diagram showing a wireless image transmission device according to the present invention.

3 is a flowchart showing a control flow in the wireless video transmission device according to the present invention.

* Description of the symbols for the main parts of the drawings *

21: transmitter 22: receiver

211,212,221,222: WLAN Card

213, 223: MCU

The present invention relates to a wireless video transmission device capable of wirelessly transmitting audio / video signals between video consumer electronic devices. More particularly, the present invention relates to a wireless video transmission device that can always maintain an optimal transmission rate in transmission of video and audio signals between a transmitter and a receiver. It relates to a wireless video transmission device.

As the demand for digital television is rapidly increasing due to the recent development of digital technology, and as household appliances become more advanced, the user can find ways to solve various wires that are easy to install and complicated for various household appliances. There is a demand.

BACKGROUND ART In general, image playback-related home appliances include a digital TV (HDTV) and a set-top box for receiving broadcast programs different from terrestrial broadcasting (eg, satellite broadcasting and cable broadcasting). And a record for storing a video / audio signal for a predetermined broadcast program in a storage medium (for example, a DVD, a video cassette, etc.) or reading and playing a video / audio signal stored in the storage medium as a TV signal. Player, etc. These various video devices operate while exchanging video / audio signals with each other.

The video / audio signal exchange between these various video devices was first performed through a cable, but as described above, as the number of cables required increases, the cable may be damaged due to complicated cables during installation or connection. In order to solve the problem of the cable, a wireless video transmission device has been proposed to exchange video and audio signals through a wireless signal.

1 is a block diagram showing a configuration of a conventionally proposed wireless video transmission device, which is provided on the side (e.g., set-top box, digital television, etc.) for transmitting a video signal and provided from the device. / Transmission unit 11 for transmitting the data as a radio signal of the set band and a video signal receiving side (for example, digital television, DVD player, etc.) is installed to receive the radio signal transmitted from the transmission unit 11 And a receiver 12 for demodulating the original video / audio / data to a video device connected to the output side.

The transmitter 11 and the receiver 12 are each provided with WLAN cards 111 and 121 which transmit and receive video, audio and data through WLAN bands (1.4 GHz) as wireless transmission / reception means.

The WLAN card 111 provided in the transmitter 11 modulates and transmits video / audio data of a set-top box or a digital TV processed in the transmitter 11 into a radio signal of a frequency band set according to a communication standard. The WLAN card 121 provided in the receiver 12 receives a radio signal of a set frequency band and demodulates the received radio signal into video / audio data.

In this case, a plurality of frequency channels used for transmitting and receiving data between the WLAN card 111 of the transmitter 11 and the WLAN card 121 of the receiver 12 exist, and the pair of WLAN cards 111 and 121 exist. In the initial operation,) sets one channel for transmitting and receiving data to each other. When the frequency channel is set, data is exchanged only through the initially set frequency channel regardless of a change in the communication environment.

Accordingly, the conventional wireless video transmission device maintains the channel as it is even if the communication channel is deteriorated due to a change in the external environment, and thus the transmission state is deteriorated. This happens.

SUMMARY OF THE INVENTION The present invention has been proposed to solve the above-mentioned problems, and an object thereof is to wirelessly maintain an optimal transmission rate by changing a channel according to a communication state in transmission of video and audio signals between a transmitter and a receiver. Video transmission device

As a construction means for achieving the above object, the present invention

Two WLAN cards each searching for a channel having an optimal transmission rate by searching a plurality of frequency channels in the WLAN frequency band, or wirelessly transmitting input video / audio data to a set frequency channel. It is equipped with an MCU which instructs transmission by instructing voice data and checks the data transmission rate. When the transmission rate decreases below the reference value, the channel is searched by another WLAN card, and when the optimal channel is set, the MCU outputs video / audio data to the WLAN. A transmitter; And

Two WLAN cards each searching multiple frequency channels of the WLAN frequency band to search for an optimal data rate channel, or receiving wireless signals transmitted from the transmitter through a set frequency channel to restore video / audio data; Instructs one WLAN card to receive data and checks the data rate. When the data rate falls below the threshold, the other WLAN card is instructed to search for a channel. It consists of a receiver having an MCU to change.

Hereinafter, with reference to the accompanying drawings will be described in detail the configuration and operation of the wireless image transmission apparatus according to the present invention.

2 is a block diagram showing the basic configuration of a wireless video transmission device according to the present invention.

2, the wireless image transmission apparatus of the present invention receives video and audio data from a predetermined video home appliance (for example, a set-top box or a digital TV) and modulates it into a wireless signal of a predetermined frequency channel. A transmitting unit 21 for transmitting and a receiving unit 22 for receiving a radio signal of a frequency channel transmitted from the transmitting unit 21, demodulating the video and audio data, and providing the demodulated image and audio data to another video home appliance (such as a digital TV or a DVD player). Is made of.

In this case, the transmitter 21 searches for a plurality of frequency channels in the WLAN frequency band to search for a channel having an optimal data rate, or two WLAN cards 211 and 212 for wirelessly transmitting input video / audio data to a set frequency channel; One of the two WLAN cards 211 and 212 applies video / audio data to one of the WLAN cards to instruct transmission and checks the data rate. When the transmission rate decreases below a reference value, the channel is searched by another WLAN card and the optimal channel is set. And the MCU 213 for outputting video / audio data to the WLAN.

The receiver 22 searches for multiple frequency channels in the WLAN frequency band to search for a channel with an optimal data rate, or receives a radio signal transmitted from the transmitter 21 through a set frequency channel to receive video / audio data. Two WLAN cards 221 and 222 restoring the data, and one of the two WLAN cards 221 and 222 instructs the reception of data and checks the data transmission rate. The MCU 223 is configured to instruct the channel search to change data reception to the WLAN card when a channel having an optimal data rate is set.

FIG. 3 is a flowchart illustrating a control flow in the wireless image transmission device configured as shown in FIG. 2.

Hereinafter, the operation of the wireless image transmission apparatus according to the present invention will be described with reference to FIGS. 2 and 3. In the following description, in order to distinguish the WLAN cards 211, 212, 221, and 222 from each other, 211 is referred to as a first WAN card, 212 as a second WLAN card, 221 as a third WLAN card, and 222 as a fourth WLAN card.

The first and second WLAN cards 211 and 212 modulate and transmit the input video / audio data into a radio signal of a set frequency channel according to the control of the MCU 213, and the third and fourth WLAN cards 221 and 222 are MCU 223. Receives a radio signal of a set frequency channel under the control of and demodulates the video / audio data included in the signal. In this case, when the first to fourth WLAN cards 211, 212, 221, and 222 are instructed to transmit data from the MCUs 213 and 223, the first to fourth WLAN cards 211, 212, 221, and 222 may search for a transmission rate of each of a plurality of channels set within an allocated frequency range of the WLAN as an initial operation before starting data transmission. Search for the best channel.

In the present invention, the first and second WLAN cards 211 and 212 of the transmitter 21 alternately perform data transmission and channel search, and the third and fourth WLAN cards 221 and 222 of the receiver 22 alternately receive data and channel. By performing the search, degradation of the communication channel (communication channel) enables data transmission and reception through other channels without interruption of data transmission. This action can be achieved by the following operation procedure.

The MCU 213 first applies video and audio data to be transmitted to the first WLAN card 211 to instruct data transmission (301). Accordingly, the first WLAN card 211 directly converts the video and audio data provided from the MCU 213 into a wireless signal through a frequency channel searched by the frequency search before data transmission and transmits the converted wireless signal.

In this manner, while performing data transmission, the MCU 213 checks the transmission rate at the time of data transmission periodically or whenever necessary (302).

Then, it is determined whether the checked transmission rate of the current data is smaller than the predetermined minimum transmission rate (303). If the transmission rate is higher than the minimum transmission rate, the video / audio data is applied to the first WLAN card 211 and transmitted through the current communication channel.

On the contrary, when the check result shows that the actual data rate of the current data falls below a predetermined minimum data rate (303), the MCU 213 instructs the second WLAN card 212 that is not currently transmitting data to search for a channel. Therefore, the second WLAN card 212 checks the data rate by searching each channel over the entire frequency band of the WLAN (304).

In operation 305, the channel having the highest data rate is set as the communication channel.

As described above, when the channel setting of the second WLAN card 212 is completed, the MCU 213 stops the operation of the first WLAN card 211 and provides video and audio data to the second WLAN card 212. Instructs data transfer. Accordingly, the second WLAN card 212 transmits the input data to the receiver 22 through the channel previously set by the channel search.

The operation of the receiver 22 is made corresponding to the operation of the transmitter 21 described above.

According to the operation of the transmitting and receiving units 21 and 22, the wireless image transmitting apparatus can transmit data while changing a channel to an optimal channel without interrupting data.

As described above, in the present invention, when the channel state deteriorates due to a change in the external environment while transmitting data in the wireless image transmission apparatus, the channel can be changed to another channel whose transmission rate is higher than the reference value without interruption of data transmission. In delivering the video and audio of a program received from a set-top box or a digital TV in real time, it is possible to maintain a certain level of transmission at all times. As a result, it is possible to provide a certain level of image quality at a video appliance connected to the receiver. It works.

Claims (1)

Two WLAN cards each searching for a channel having an optimal transmission rate by searching a plurality of frequency channels in the WLAN frequency band, or wirelessly transmitting input video / audio data to a set frequency channel. It is equipped with an MCU which instructs transmission by instructing voice data and checks the data transmission rate. When the transmission rate decreases below the reference value, the channel is searched by another WLAN card, and when the optimal channel is set, the MCU outputs video / audio data to the WLAN. A transmitter; And Two WLAN cards each searching multiple frequency channels of the WLAN frequency band to search for an optimal data rate channel, or receiving wireless signals transmitted from the transmitter through a set frequency channel to restore video / audio data; Instructs one WLAN card to receive data and checks the data rate. When the data rate falls below the threshold, the other WLAN card is instructed to search for a channel. A receiver having an MCU to change; Wireless image transmission device comprising a.

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