KR20110070373A - Method and apparatus for transmitting media signal - Google Patents

Abstract

PURPOSE: A signal transmission method and apparatus are provided to control a scaling parameter according to a wireless network status. CONSTITUTION: A controller detects a wireless network status between a transmitter and a receiver(400). The controller controls a scaling parameter on the basis of the detected wireless network status(410). If the control of the scaling parameter is completed, a scaler performs the scaling of a video signal according to the controlled scaling parameter(420). An RF(Radio Frequency) transmitter transmits the scaled video signal to the receiver(430).

Description

Method and apparatus for transmitting a signal {Method and apparatus for transmitting media signal}

The present invention relates to a method and apparatus for transmitting and receiving a signal, and more particularly, to a method and apparatus for transmitting and receiving a media signal using wireless communication.

In general, a display device includes a broadcast receiving unit that receives and processes a media signal from an airwave, a cable, and other external devices (VCR, DVD, etc.) and outputs it, and a display unit that displays an image of the processed media signal on a screen. Can be.

On the other hand, the broadcast receiving unit and the display unit may be configured separately, each of which is a wireless (wireless) method of transmitting and displaying the media signal received recently using a separate receiving device to the display device using a wireless communication Display systems are provided.

An object of the present invention is to provide a signal transmission method and apparatus capable of efficiently transmitting and receiving media signals using wireless communication.

According to an aspect of the present invention, there is provided a signal transmission method comprising: transmitting a media signal to a receiving device connected through a wireless network, and receiving an image signal; Detecting a state of the wireless network; Adjusting a scaling parameter based on the detected wireless network condition; Scaling the video signal using the adjusted scaling parameter; And transmitting the scaled video signal to the receiving device.

According to an aspect of the present invention, there is provided a transmission apparatus comprising: an interface unit for transmitting a media signal to a reception apparatus connected through a wireless network, and receiving an image signal from an external device; A scaler for scaling the input video signal according to a scaling parameter; A controller for adjusting the scaling parameter based on the state of the wireless network; And a transmitter for transmitting the scaled video signal to the receiving device.

In addition, the signal transmission method may be implemented as a computer-readable recording medium recording a program for execution in a computer.

According to an embodiment of the present invention, by adjusting the scaling parameter according to the wireless network state, it is possible to transmit and receive a video signal without deterioration of image quality.

Hereinafter, a signal transmission method and apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.

1 is a block diagram illustrating an embodiment of a configuration of a signal transmission / reception system, and the signal transmission / reception system may include a transmission device 100 and a reception device 200.

Referring to FIG. 1, the transmission apparatus 100 receives a media signal including an image from an airwave, a cable, or an external device, and converts the received media signal into data in a wireless transmission format for wireless transmission. do.

The receiving device 200 receives and processes data wirelessly transmitted from the transmitting device 100, and for this purpose, at least one wireless communication standard for wirelessly transmitting and receiving data between the transmitting device 100 and the receiving device 200 is provided. It may be set in advance.

Meanwhile, the transmitting apparatus 100 may include an HDMI or a high-definition multimedia interface (HDMI) terminal, a universal serial bus (USB) terminal, a component terminal, an external input terminal, an RGB terminal, and an antenna to which an external device is connected. Various input terminals such as a cable terminal may be provided to receive a media signal using the input terminal.

The transmitting device 100 may be a set-top box (STB) for receiving a media signal through a wired or wireless network, converting the received media signal, and wirelessly transmitting the received media signal to the receiving device 200.

However, the transmitting apparatus 100 according to the present invention is not limited to the set top box STB, and may include any kind of apparatus capable of receiving a media signal transmitted from the outside and wirelessly transmitting it to the receiving apparatus 200. .

For example, the transmitting device 100 according to the present invention may be provided in a portable terminal such as a computer or a mobile phone.

In addition, the reception apparatus 200 may receive and process data transmitted wirelessly from the transmission apparatus 100 and then transmit the data to an external device that outputs an image or audio included in a media signal.

For example, the reception apparatus 200 may convert an image signal wirelessly transmitted from the transmission apparatus 100 into a form that can be displayed on a display apparatus (not shown) and then output the converted image signal. More specifically, when the video signal wirelessly transmitted from the transmitting device 100 is encoded by a coding scheme such as MPEG, the receiving device 200 decodes the received video signal. And output to a display device (not shown).

According to an embodiment of the present invention, the transmitting device 100 and the receiving device 200 may be connected to various wireless communication standards, for example, wireless HD (WiHD), wireless home digital interface (WHDi), or wireless LAN (WiFi). Media signals may be transmitted and received using communication standards.

The WiHD uses a frequency band of about 60 GHz and transmits and receives data at a transmission rate of about 4 Gbps, thereby enabling transmission without compressing HD image data of 1080p (1920 × 1080). However, since the WiHD uses a high frequency of 60 GHz band, the data transmission / reception distance is about 10 m, and the transmission / reception quality may be easily affected by peripheral obstacles in the installation space.

The WHDi may transmit and receive data at a transmission rate of about 1.8 Gbps using a frequency band of about 5 GHz. In addition, since the WHDi uses a relatively low frequency band of 5 GHz, the transmission / reception distance is about 30 m, and the transmission / reception quality may not be greatly influenced by peripheral obstacles in the installation space. On the other hand, according to a transmission rate of about 1.8 Gbps, when the HD video data of 1080p (1920 x 1080) is to be transmitted using the WHDi, the transmitter 100 needs to compress and transmit the HD video data.

In addition, the WiFi may transmit and receive data at a transmission rate of about 54 Mbp using a frequency band of 2.4 GHz. Since the WiFi uses a low frequency band of 2.4 GHz, the transmission and reception distance is about 50 to 200 m, and the transmission and reception quality may be almost unaffected by peripheral obstacles in the installation space. On the other hand, according to a low transmission rate of about 54Mbp, if you want to transmit 1080p (1920 × 1080) HD video data using the WiFi, the transmitting device 100 must compress and transmit the HD video data, accordingly An image quality deterioration may occur in an image signal received by the reception apparatus 200.

Meanwhile, in addition to the wireless communication standard described above, the transmitting device 100 and the receiving device 200 may use various short range wireless communication standards such as Bluetooth, ZigBee, or binary CDMA. It is possible to wirelessly transmit and receive data according to a media signal using communication standards such as).

According to an embodiment of the present invention, the transmitting device 100 and the receiving device 200 may transmit and receive video and audio data using any one of the various wireless communication standards as described above.

Meanwhile, the transmitter 100 and the receiver 200 may transmit and receive video and audio data using two or more of the above-described wireless communication standards. For example, the transmitter 100 and the receiver may be used. According to the performance, the installation environment, and the resolution of the image, any one of the two or more supported standards may be selected and used for data transmission and reception.

2 is a block diagram illustrating another embodiment of the configuration of the signal transmission and reception system, and the signal transmission and reception system may include a transmission apparatus 100 and a plurality of reception apparatuses 200, 210, and 220.

Referring to FIG. 2, the transmitting device 100 may be connected to the plurality of receiving devices 200, 210, and 220 through a wireless network. That is, the transmitting apparatus 100 may convert the media signal wirelessly transmitted data received from the outside and then wirelessly transmit the data to at least one of the plurality of receiving apparatuses 200, 210, and 220.

For example, the transmitting device 100 may select one or more receiving devices from among a plurality of receiving devices 200, 210, and 220 to receive a media signal, and select the media signal received from the outside by the user. Wireless transmission to the receiving device.

To this end, the transmitter 100 may include a plurality of wireless transmitters (not shown) corresponding to each of the plurality of receivers 200, 210, and 220, and a plurality of wireless transmitters (not shown). Each may wirelessly transmit video and audio data to a corresponding receiving device.

The wireless communication standard for data transmission and reception may be the same or different from each other in each of the plurality of receiving apparatuses 200, 210, and 220. For example, wireless communication standards for receiving data from each of the plurality of receiving devices 200, 210, and 220 are different from each other according to the performance or the installation location of each of the plurality of receiving devices 200, 210, and 220. May be set.

Meanwhile, the transmitting device 100 may include a number smaller than the number of the plurality of receiving devices 200, 210, and 220, for example, one wireless transmitter (not shown). In this case, the transmitting device 100 ) May wirelessly transmit data using multi-channel communication, that is, using a plurality of channels corresponding to each of the plurality of receiving apparatuses 200, 210, and 220.

3 is a block diagram illustrating another embodiment of the configuration of the signal transmission and reception system, and description of the same elements as those described with reference to FIGS. 1 and 2 in the signal transmission and reception system illustrated in FIG. 3 will be omitted below. .

Referring to FIG. 3, the display apparatus 300 according to an exemplary embodiment of the present invention may include the receiving apparatus 200 and the display module 310 as described above.

That is, the transmitting apparatus 100 receives a media signal from the outside and wirelessly transmits the media signal to the receiving apparatus 200, and the receiving apparatus 200 provided in the display apparatus 300 displays the wirelessly transmitted data. The signal may be processed and output to the display module 310.

The display module 310 may display an image using an image signal input from the receiving device 200, and for this, a liquid crystal display (LCD), a plasma display panel (PDP), an electro luminescent display (ELD), and a VFD It may include a display panel (not shown) of various display methods such as a (Vacuum Fluorescent Display).

4 is a block diagram illustrating a configuration of a transmitting apparatus according to an exemplary embodiment of the present invention. The transmitting apparatus 100 illustrated includes an interface unit 110, a scaler 120, a controller 130, and an RF transmitter 140. It may include.

Referring to FIG. 4, the interface unit 110 receives a media signal from an external device, and tunes and receives a signal corresponding to a broadcast channel selected by a user among data streams transmitted to the outside through an antenna or a cable. It may be connected to a tuner (not shown) or an external device and include input terminals such as HDMI, USB, component, and RGB for receiving a signal.

Meanwhile, the media signal received from the external device through the interface unit 110 may include an image signal having a specific resolution and frequency.

The scaler 120 scales and outputs an image signal received from the interface unit 110 according to a scaling parameter.

The scaling parameter may include a resolution, a frequency, and a color format of an image, and the scaler 120 may convert the resolution, frequency, and color format of an input image signal according to the scaling parameter. .

For example, the scaler 120 may convert the resolution of an image signal of 1080p resolution and 60 Hz frequency input from an external device into 720p or a frequency of 30 Hz and output the converted signal.

The scaler 120 may select and output a color format of an image signal from a YCbCr 444 or YCbCr 422 format.

The transmitter 140 wirelessly transmits an image signal output from the scaler 120 to the receiver 200.

The controller 130 controls the overall operation of the transmission apparatus 100, and more specifically, the scaler 120 and the video signal having a specific resolution, frequency, and color format may be wirelessly transmitted to the reception apparatus 200. The operation of the transmitter 140 may be controlled.

The data transmission / reception performance between the transmitter 100 and the receiver 200 that transmits and receives data wirelessly, that is, the signal reception sensitivity at which the signal transmitted from the transmitter 100 is received by the receiver 200 is a transmitter ( It may be influenced by the distance between the receiver 100 and the receiver 200, the presence of peripheral obstacles, or the directions of the antennas provided in the respective devices.

In particular, when data is transmitted and received between the transmitting apparatus 100 and the receiving apparatus 200 using WiHD having a high frequency band of several tens of GHz, for example, a frequency band of about 60 GHz, the data transmitting / receiving distance is short as about 10 m. In addition, due to the high linearity, the signal reception sensitivity may be affected by surrounding obstacles.

In addition, when the signal reception sensitivity is lowered as described above, data loss may occur between the transmitting device 100 and the receiving device 200, and accordingly, an image received and displayed through the receiving device 200 is displayed. Quality may be degraded.

According to an embodiment of the present invention, the controller 130 may adjust the scaling parameter based on a state of a wireless network between the transmitting device 100 and the receiving device 200, and the scaler 120 adjusts the adjusted scaling. The input video signal may be scaled according to the parameter.

For example, when the state of the wireless network is not good, the controller 130 may reduce the resolution or frequency of the video signal transmitted to the receiving device 200 by adjusting the scaling parameter.

According to an embodiment of the present invention, the state of the wireless network is a signal reception sensitivity measured at the transmitting device 100 or the receiving device 200, for example, received signal strength (RSSI) or packet error rate. (PER, Packet Error Rate) or the like.

5 is a block diagram illustrating a configuration of a receiving apparatus according to an exemplary embodiment of the present invention. The receiving apparatus 100 includes an RF transceiver 210, a reception sensitivity measuring unit 220, and a signal processing unit 230. It may include.

Referring to FIG. 5, the RF transceiver 210 may wirelessly receive an image signal from a transmission device 100 connected through a wireless network, for example, a network using a wireless communication standard such as WiHD, WHDi, or WiFi.

For example, the RF receiver 201 may receive a media signal including uncompressed AV data from the reception apparatus 100, and for this purpose, transmit the media signal from the transmission apparatus 100 using a WiHD wireless communication scheme. Can be received.

The reception sensitivity measuring unit 220 may measure a reception sensitivity of a signal received from the transmitter 100, for example, a received signal strength indicator (RSSI) or a packet error rate (PER). .

The signal reception sensitivity is measured by the reception device 200, more specifically, by the reception sensitivity measuring unit 220 provided in the reception device 200, and then transmitted to the transmission device 100 through the RF transceiver 210. Can be.

For that purpose, the RF transceiver 210 may include an antenna (not shown) and a converter (not shown), for example, an up converter and a down converter.

Meanwhile, the transmission device 100 may wirelessly transmit a test signal for measuring the signal reception sensitivity to the reception device 200. Unlike the above embodiment, the transmission device 100 further includes a separate module for measuring the reception signal sensitivity. You may.

The signal processor 230 may convert the signal received from the RF transceiver 211 into a form that can be output and output the converted signal. For example, when a signal received from the transmitting apparatus 100 is compressed according to a coding scheme such as MPEG, the signal processor 230 may include an A / V processor for decoding the received video and audio signals. Not shown).

Hereinafter, a signal transmission method according to an embodiment of the present invention will be described in detail with reference to FIG. 6.

6 is a flowchart illustrating a signal transmission method according to an exemplary embodiment of the present invention. The signal transmission method shown in FIG. 4 will be described with reference to a block diagram showing the configuration of the transmission apparatus 100 shown in FIG.

Referring to FIG. 6, first, a wireless network state between a transmitting device 100 and a receiving device 200 is detected (step 400).

For example, the state of the wireless network may be detected by a signal reception sensitivity measured by the transmitting device 100 or the receiving device 200, more specifically, by receiving signal strength (RSSI) or packet error rate (PER). .

The transmitting device 100 includes a separate module (not shown) for measuring the signal receiving sensitivity, or the signal receiving sensitivity measured by the receiving device 200, for example, received signal strength (RSSI) or packet error rate. Information regarding the PER may be received from the receiving device 200.

Thereafter, the controller 130 adjusts scaling parameters based on the detected wireless network state (step 410).

According to an embodiment of the present invention, the scaling parameter may include a resolution, a frequency, a color format, and the like of the image, and accordingly, the controller 130 controls the resolution, frequency, and A color format or the like can be set based on the detected wireless network state.

For example, when the measured received signal strength (RSSI) decreases, the controller 130 may determine that the wireless network is in a bad state and reduce the resolution of the image among the scaling parameters. When the (RSSI) increases, the resolution of the image may be increased.

In addition, when the measured received signal strength (RSSI) decreases, the controller 130 may determine that the wireless network is in a bad state and may reduce the frequency of the image among the scaling parameters. If) increases, the frequency of the image can be increased.

On the other hand, if the measured packet error rate (PER) increases, the controller 130 may determine that the wireless network is in a bad state and may reduce the resolution of the image among the scaling parameters. If it decreases, the resolution of the image may be increased.

In addition, when the measured packet error rate (PER) is increased, the controller 130 may determine that the wireless network is in a bad state and may reduce the frequency of the image among the scaling parameters. If it decreases, the frequency of the image may be increased.

According to an embodiment of the present invention, in step 410, the amount of data that can be transmitted can be calculated according to the detected wireless network state, and the resolution and frequency of the image can be adjusted according to the calculated amount of data.

That is, the amount of data that can be transmitted decreases when the state of the wireless network is poor, and the amount of data that can be transmitted may increase when the state of the wireless network is good.

The amount of data may be determined according to a modulation scheme. For example, the transmitting device 100 may include a modulator (not shown), and the modulator (not shown) may output modulation symbols by modulating an input signal according to a preset modulation scheme.

The modulation scheme may include Binary Phase Shift Keying (BPSK), Quadrature Phase Shift Keying (QPSK), Quadrature Amplitude Modulation (QAM), Pulse Amplitude Modulation (PAM), Phase Shift Keying (PSK), and the like.

For example, the data amount according to the modulation scheme is about 614.4 Kbps when the QPSK modulation scheme and 1/3 code rate are applied, and the data transmission when the QPSK modulation scheme and 2/3 code rate are applied. The characteristic is about 1228.8 Kbps, and the data transmission characteristic when 8PSK modulation method and 2/3 code rate is applied is about 1843.2 Kbps, and the data transmission characteristic when 16QAM modulation method and 2/3 code rate is applied is about 2457.6 Kbps day. Can be.

As described above, as the transmission apparatus 100 determines the modulation scheme, the amount of data that can be transmitted to the transmission apparatus 200 may be calculated, and the controller 130 may use the scaling parameter, that is, the calculated data amount. The resolution or frequency of the image can be adjusted.

When the adjustment of the scaling parameter is completed as described above, the scaler 120 scales the video signal according to the adjusted scaling parameter (step 420), and the RF transmitter 140 receives the scaled video signal by the receiving apparatus 200. In step 430.

That is, the scaler 120 may convert and output the resolution or frequency of the video signal input from the external device through the interface unit 110 according to the adjusted scaling parameter, and accordingly, through the RF transmitter 140. The data amount of the signal wirelessly transmitted to the receiving device 200 may be changed.

For example, assuming that the resolution and frequency of an image signal input from an external device are 1080i and 60 Hz, when the measured received signal strength (RSSI) decreases below a reference value, the controller 130 adjusts the scaling parameter. By converting the resolution of the video signal to 730p can be output.

In addition, when the measured received signal strength RSSI decreases below a reference value, the controller 130 may adjust the scaling parameter to convert the frequency of the image signal to 30 Hz and output the converted signal.

Meanwhile, when the measured received signal strength RSSI increases beyond the reference value, the controller 130 may adjust the scaling parameter to convert the resolution of the image signal to 1080p and output the same.

In addition, when the measured received signal strength RSSI increases beyond the reference value, the controller 130 may adjust the scaling parameter to convert the frequency of the image signal to 70 Hz and output the converted signal.

In addition, the above-described signal transmission method according to the present invention can be stored in a computer-readable recording medium that is produced as a program for execution in a computer, and examples of the computer-readable recording medium include ROM, RAM, CD- ROMs, magnetic tapes, floppy disks, optical data storage, and the like, and also include those implemented in the form of carrier waves (eg, transmission over the Internet).

The computer readable recording medium can be distributed over network coupled computer systems so that the computer readable code is stored and executed in a distributed fashion. In addition, functional programs, codes, and code segments for implementing the broadcast reception method may be easily inferred by programmers in the art to which the present invention belongs.

While the present invention has been particularly shown and described with reference to exemplary embodiments thereof, it is to be understood that the invention is not limited to the disclosed exemplary embodiments, but, on the contrary, It will be understood by those skilled in the art that various changes in form and details may be made therein without departing from the spirit and scope of the present invention.

1 and 3 are block diagrams illustrating embodiments of a signal transmission / reception system.

4 is a block diagram showing the configuration of a transmitting apparatus according to an embodiment of the present invention.

5 is a block diagram showing the configuration of a receiving apparatus according to an embodiment of the present invention.

6 is a flowchart illustrating a signal receiving method according to an embodiment of the present invention.

Claims (13)

A method for transmitting a media signal to a receiving device connected over a wireless network, the method comprising: Receiving an image signal; Detecting a state of the wireless network; Adjusting a scaling parameter based on the detected wireless network condition; Scaling the video signal using the adjusted scaling parameter; And And transmitting the scaled video signal to the receiving device. The method of claim 1, wherein the scaling parameter is A signal transmission method comprising at least one of a resolution, a frequency, and a color format of an image. The method of claim 1, wherein the detecting step A signal transmission method for measuring at least one of a received signal strength (RSSI, Received Signal Strength Indicator) and a packet error rate (PER, Packet Error Rate). The method of claim 3, wherein the detecting step And receiving information about at least one of a received signal strength (RSSI) and a packet error rate (PER) measured by the receiving device. The method of claim 2 and 3, wherein the adjusting step And reducing at least one of a resolution and a frequency of the image as the received signal strength (RSSI) decreases. The method of claim 2 and 3, wherein the adjusting step And at least one of a resolution and a frequency of the image decreases as the packet error rate (PER) increases. The method of claim 1, wherein said adjusting step Calculating an amount of data that can be transmitted according to the detected wireless network state; And Adjusting the scaling parameter using the calculated amount of data. The method of claim 8, And the data amount is determined according to a modulation scheme. The method of claim 1, wherein the transmitting step A signal transmission method for transmitting an image signal to the receiving device using a wireless communication method of any one of WiHD, WHDi and WiFi. A computer-readable recording medium having recorded thereon a program for executing the method according to any one of claims 1 to 9. An apparatus for transmitting a media signal to a receiving apparatus connected over a wireless network, the apparatus comprising: An interface unit for receiving an image signal from an external device; A scaler for scaling the input video signal according to a scaling parameter; A controller for adjusting the scaling parameter based on the state of the wireless network; And And a transmitter for transmitting the scaled video signal to the receiver. The method of claim 11, wherein the scaling parameter is Transmitting apparatus including at least one of the resolution, frequency and color format of the image. The method of claim 1, wherein the wireless network state is And at least one of a received signal strength (RSSI) and a packet error rate (PER).

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