KR100778477B1 - Wireless interface apparatus and method in hdmi - Google Patents

Abstract

An apparatus and a method for a wireless interface in an HDMI are provided to construct wireless HDMI interface environment without a limit of device mobility and inconvenience in the installation of a cable and transmit CEC(Consumer Electronics Control) information stably even under wireless HDMI environment, thereby realizing a virtual repeater with the same performance as the performance of a cable repeater without separate costs. A wireless interface device for HDMI(High Definition Multimedia Interface) includes a first device among n devices(11,12,13) and a first wireless communication unit among n wireless communication units connected to the first device. The first wireless communication unit communicates audio/video signals to a second wireless communication unit by wireless and performs wireless communication with remaining wireless communication units except the first wireless communication unit among the n wireless communication units to update information including the location and wireless address of remaining devices except the first device among the n devices at intervals when the audio/video signals are transceived. The N is a natural number.

Description

Wireless interface device and method of HMDM {WIRELESS INTERFACE APPARATUS AND METHOD IN HDMI}

1 is a diagram illustrating a connection between devices including repeaters in a wired HDMI environment.

2 is a diagram illustrating a problem when implementing wireless HDMI.

Figure 3a illustrates the connection and status of the CEC bus in wired HDMI.

Figure 3b illustrates the connection and status of the CEC bus in wireless HDMI.

4 illustrates an HDMI data stream and a control signal in wireless HDMI according to an embodiment of the present invention.

5 is a view showing a connection state between each device in the wireless HDMI according to an embodiment of the present invention.

6 is a diagram illustrating a concept of wirelessly transmitting stable user electronic control information in wireless HDMI according to an embodiment of the present invention.

7 illustrates a wireless HDMI interface device in accordance with an embodiment of the present invention.

11: DVD 12: D-VHS

13: STB (Set Top Box) 14: Repeater

15: TV 21,31,41,51: first to fourth devices

22,32,42,52: 1st ~ 4th CEC bus 23,33,43,53: 1st ~ 4th wireless communication means

The present invention relates to a high definition multimedia interface (HDMI), and more particularly, to implement a virtual repeater having a function substantially equivalent to that of a repeater connected by wire under a wireless interface environment (HDMI) of the HDMI, CEC The present invention relates to a wireless interface method and apparatus capable of stably transmitting signals wirelessly.

Recently, as multimedia contents are diversified, various multimedia devices for reproducing and transmitting various multimedia contents have been developed together, and interface technologies for simple and lossless signal connection between them have been developed.

The most representative multimedia interfaces are DVI and HDMI. DVI (Digital Visual Interface) is a transmission standard established by a consortium formed by leading companies in the computer industry called DIGITAL DISPLAY WORKING GROUP to digitally connect monitors and PCs. The DVI standard has been widely applied to not only PCs and monitors but also commercial plasma displays and peripherals. Recently, HDMI standards, which are more suitable for high-definition multimedia environments, have been developed and commercialized.

HDMI is a high-speed multimedia interface that integrates and transmits uncompressed full digital audio and video signals, and can transmit all ATSC and HDTV, and devices such as audio / video sources, set-top boxes and DVD players, monitors, and digital TVs. Provides an interface between

This HDMI is simple to process 5Gbps digital video and audio without compression, simple circuit, no quality deterioration, and copyright protection of content by HDCP (High-bandwidth Digital Content Protection). It has the advantage of being easy to use with a single cable connection. In addition, it is compatible with DVI, which is mainly used in the computer industry, and its application is a multimedia interface that is being developed.

Meanwhile, the HDMI standard defines a user electronic control (CEC) and a CEC bus that can easily control a plurality of networked multimedia devices. According to the CEC, control of multimedia devices connected via HDMI is individually controlled. Since it can be simply performed on one device without the user, the user can conveniently link the devices.

HDMI, which has the advantages described above, is also generally connected to each device by wire using a cable. However, the use of such a cable makes the connection between the devices cumbersome, and the mobility of each device is limited, thereby limiting its installation. Therefore, a lot of attention is focused on WIRELESS HDMI technology, which transmits HDMI audio / video data wirelessly.

However, in the case of the WIRELESS HDMI, due to the nature of the frequency used to connect multiple devices at the same time, and also in the use of the CEC bus in the wireless interface has a lot of difficulties, including collision problems.

An object of the present invention to solve the above problems is to provide a wireless interface device and method of the HDMI that implements a virtual repeater similar to the repeater of the wired HDMI in a directional wireless HDMI environment.

Another object of the present invention is to provide a wireless interface device and method of HDMI that provides a stable CEC bus even in a wireless HDMI environment.

In accordance with an aspect of the present invention, there is provided a wireless interface device including N devices and N wireless communication means connected to the N devices, respectively. A first one of the devices; And first wireless communication means of the N wireless communication means connected to the first device, wherein the first wireless communication means is the N wireless devices connected to a second device of the N devices. Between the second wireless communication means of the communication means and the wireless communication of the audio / video signal, and the wireless communication of the audio / video signal, the location and radio address of the remaining devices except the first one of the N devices In order to update the information including a, the wireless communication means other than the first wireless communication means of the N wireless communication means is made to perform wireless communication, wherein N is a natural number.

In addition, a wireless interface device according to an embodiment of the present invention for achieving the above object, a wireless interface device of HDMI having N CEC buses and N wireless communication means connected to the N CEC buses, respectively A first CEC bus of the N CEC buses; And a first wireless communication means of the N wireless communication means connected to the first CEC bus, wherein the first wireless communication means, when detecting a CEC signal, is the first of the N CEC buses; The first reservation signal for reserving the remaining CEC buses except for the CEC bus is transmitted to the remaining wireless communication means except for the first one of the N wireless communication means, and after the predetermined time, the CEC signal is transmitted to the corresponding CEC bus. And a second reservation signal corresponding to the length of the CEC signal to the first CEC bus of the N CEC buses and the remaining CEC buses except for the corresponding CEC bus, wherein N is a natural number. .

In addition, the air interface method according to an embodiment of the present invention for achieving the above object, the air interface method of the HDMI-based system consisting of N devices and N wireless communication means connected to the N devices, respectively A second radio of said N wireless communication means connected to a second device of said N devices, wherein a first wireless communication means of said N wireless communication means connected to a first one of said N devices; Between the communication means and the audio / video signal wirelessly, and updating the information including the location and the radio address of the remaining devices except the first one of the N devices between the wireless communication of the audio / video signal. For the remaining wireless communication means except for the first one of the N wireless communication means. It consists of performing a wireless communication, where N is a natural number.

In addition, the wireless interface method according to an embodiment of the present invention for achieving the above object, the wireless interface method of HDMI having N CEC buses and N wireless communication means connected to the N CEC buses, respectively The first CEC bus of the N CEC buses may detect the CEC signal of the first CEC bus of the N CEC buses, except for the first CEC bus of the N CEC buses. Transmitting a first reservation signal for reserving the data to other wireless communication means except for the first one of the N wireless communication means; And after a predetermined time, the first wireless communication means transmits the CEC signal to the corresponding wireless communication means, and the remaining wireless communication means except for the first wireless communication means and the corresponding wireless communication means among the N wireless communication means. And transmitting a second reservation signal corresponding to the length of the CEC signal, wherein N is a natural number.

Hereinafter, the most preferred embodiments of the present invention will be described with reference to the accompanying drawings so that those skilled in the art can easily implement the technical idea of the present invention.

1 is a diagram illustrating a connection state between devices in a HDMI environment in which various multimedia devices including a repeater (DVD, D-VHS, STB) are connected by a wire or the like. The repeater shown in FIG. 1 has four or more HDMI connectors, and all the lines such as three HDMI inputs and one HDMI output are connected. Here, since the repeater has at least one HDMI input and at least one HDMI output, the repeater may function as an HDMI SINK or an HDMI SOURCE.

According to the HDMI standard, the aforementioned repeater must implement at least one of the following functions.

1. Repeater function

One HDMI input, one HDMI output, cable extension purpose

2. Switch function

Multiple HDMI Inputs, Multiple HDMI Outputs, Multiple HDMI Source Selection

3. Distributor function

Single HDMI Input, Multiple HDMI Output (Only one output active)

4. Duplicator function

Single HDMI input, multiple HDMI outputs (More than one device active)

And the following functions must be implemented as mandatory.

1.E-EDID Handling (Enhanced Extended Display Identification Data Handling)

The ability to store E-EDID signals (Stored EDID) or forward E-EDID (Forwarding EDID)

2.Fully wired CEC connection

It is easy to implement a repeater having such a function in a wired HDMI environment, but it is difficult to implement a repeater having such a function when connecting HDMI-based multimedia devices wirelessly. The reason is shown in FIG.

2, in a wireless HDMI environment, multiple multimedia devices are not connected at the same time as a wired connection. In other words, broadcasting is impossible. This is because of the characteristics of radio waves used in wireless HDMI, because wireless HDMI (Wireless HDMI) uses a highly directional mmWave.

2 shows a wireless HDMI implementation using mmWave. Referring to this, it can be seen that several devices are not connected at the same time, but only one device and one device are connected. In other words, HDMI data streaming only happens at Peer To Peer at a moment.

Therefore, in order to implement wireless HDMI, it is necessary to continuously check and know the approximate location of each multimedia device and its wireless address. If the location of a multimedia device is different from the previous one or its wireless address is different from the previous one, if the location and the changed address are not known in advance, the device connection can be changed immediately according to the user's request. none.

And even in a wireless HDMI environment, additional signals such as user electronic control (CEC) must be able to be transmitted. In the wired HDMI method, the CEC information is transmitted through a dedicated CEC bus so that the CEC information can be obtained and the right to occupy the CEC bus can be prevented from causing a collision of CEC data. However, if a slow operating CEC is to be transmitted through a wireless interface using a single analog channel, the CEC information can be transmitted through packetization only after all the CECs are received, thereby receiving and transmitting the corresponding CEC information. If the CEC bus is occupied by another device within the delay time according to the process, the collision of CEC information occurs.

3A and 3B illustrate a state of a CEC bus in a wired environment and a wireless environment. Referring to FIG. 3A, a plurality of multimedia devices are connected through a single wired CEC bus so that all devices are connected in a wired environment. You can see that you are using a wired CEC bus. Therefore, in such a wired HDMI environment, signal arbitration to give a device a right to use the CEC bus to prevent collision between CEC signals was not so difficult.

However, referring to the wireless HDMI case shown in FIG. 3B, a plurality of devices are shown from the first device to the Nth device, and each device is connected to one side of the CEC buses, respectively.

The other end of the CEC buses is provided with a plurality of wireless interfaces (wireless interfaces 1 to N) for wireless transmission of additional information such as HDMI audio / video signals and CEC signals.

At this time, although all the devices are connected to the wireless network, since the directional wireless network can provide only one connection at the same time, the aforementioned collision problem is very high.

4 to 5 illustrate an embodiment of the present invention, which illustrates a virtual repeater implementation enabling multipoint connection equivalent to that of a wired repeater in a directional wireless HDMI interface.

First, referring to FIG. 4, since the actual data streaming (HDMI AUDIO / VIDEO STREAMING) occurs only at Peer to Peer at a moment due to the characteristic of the directional wireless HDMI interface, multimedia in the middle of HDMI data streaming in consideration of this point A control signal is transmitted to obtain coarse information about the devices.

This will be described in detail with reference to FIG. 5 as follows. First, when HDMI audio / video data streaming is being transmitted wirelessly between the TV and the DVD player, the TV side provides an overview of the devices (DVD, D-VHS, Set-Top Box (STB)) connected to the wireless HDMI (the location thereof). Control signal for continuously updating wireless information) or wireless communication between HDMI audio / video data streaming.

That is, the wireless communication means (not shown in FIG. 5) included in the TV transmits and receives HDMI data to and from the DVD player, and provides the approximate location of the remaining multimedia devices including the DVD player and its wireless address therebetween. Perform wireless communication to obtain.

In this case, the wireless communication performed to obtain the outline information (including the location and the wireless address) is broadcast because it is not directive, and the multimedia device side receiving the broadcasted radio wave receives its own location and wireless address. Send the included reply to the TV. On the TV side, each device receives a reply and updates its location and radio address except for itself. Such wireless communication is periodically performed between HDMI data streaming, so that the TV side can continuously maintain a wireless connection such as a virtual repeater.

That is, when the user wants to change the device currently connected through the CEC, the present invention knows the location and radio address of the changed devices in advance and can immediately respond to the user's request. In addition, the control signal shown in FIG. 5 is a signal including both the signal broadcast from the TV side and the reply of each device thereto.

In FIG. 4, when the control signal according to the present invention is wirelessly communicated between HDMI data streaming, the time for which the control signal is wirelessly communicated is extremely short compared to the HDMI data streaming. That is, since the HDMI data streaming is an uncompressed AV signal, the time required for transmitting the control signal of the present invention is extremely small compared to the HDMI data streaming.

According to the present invention, it is possible to continuously know the information about where the devices are located in the current HDMI cluster, what the radio address is, and whether the new device has been added or the existing device has been removed. As a result, a reliable wireless HDMI environment can be established.

6 and 7 illustrate a method and a device for transmitting CEC information according to an embodiment of the present invention, with reference to them, illustrating a method for transmitting CEC information according to the present invention.

In the existing wired HDMI environment, what kind of multimedia devices are connected (eg, DVD, D-VHS, STB) or control of each device is performed through the CEC bus.

Therefore, if the CEC bus having almost the same performance as that of the wired HDMI CEC bus can be realized wirelessly, stable control is possible even under the wireless HDMI environment. However, in the case of a wireless HDMI environment, the aforementioned solution is necessary because of the directivity of the radio waves used.

First, a CEC transmission method according to an embodiment of the present invention will be described with reference to FIG. 6 and will be described in more detail with reference to FIG. 7. A total of four devices are shown in FIG. 6, and a device to use the CEC bus is a TV.

When the TV side detects that the CEC signal is activated on the CEC bus, the TV sends a two-frame reservation message to the device 2, device 3 and device 4 to reserve the CEC bus for two CEC frame intervals.

Upon receiving the two frame reservation message, the second to fourth devices reserve the corresponding CEC bus for two CEC frame periods.

The first frame of the CEC information specifies the sender object and the receiving object (RECEIVER), and the second frame specifies the opcode. Using the first frame and the second frame, the total length of the CEC message can be known.

After determining the total length of the CEC message, the TV side transmits the CEC message to the target device as shown in FIG. 6, and the total length of the CEC message to devices other than the target device (here, N frames). A reservation message is sent to reserve a CEC bus corresponding to an N frame length corresponding to.

Using this method, it is possible to prevent a collision of CEC signals even under a wireless HDMI environment, and to transmit wireless CEC information almost equivalent to a wired CEC connection.

7 is a diagram illustrating a wireless HDMI interface device according to an embodiment of the present invention, with reference to this will be described in more detail the wireless CEC information transmission.

7 shows the first to fourth devices 21, 31, 41, and 51, the first to fourth CEC buses 22, 32, 42, and 52, and the first to fourth wireless communication means 23, 33, and 43. , 53).

Here, the first to fourth devices are multimedia devices such as TV, DVD, STB, Digtal-VHS, etc., and the first CEC bus 22 is a CEC connected between the first device 21 and the first wireless communication means 23. It is a bus.

The first wireless communication means 23 to the fourth wireless communication means 53 are connected via a wireless network.

Assuming that the first device 21 intends to transmit CEC information to the third device 41 in the wireless HDMI interface device configured as described above, it will be described below.

First, the first device 21 transmits a CEC signal to the first wireless communication means 23 via the first CEC bus 22. At this time, when the CEC signal is detected on the first CEC bus 22 on the first wireless communication means 23 side, the second to fourth wireless communication means 33, 43, 53 are provided on the second to fourth intervals by two frame sections. A first reservation signal is sent to reserve the CEC buses 32, 42, 52.

At this time, the configuration of the CEC signal is the start bit is located in the foremost, followed by the header or data block, OPCODE and OPPERAND corresponding to the OPCODE, if the start bit is loaded on the first CEC bus to the first reserved signal You can also use the method of transmission.

The first reservation signal is generated on the second to fourth CEC buses 32, 42, and 52 by generating a null frame having a length of two frames on the second to fourth wireless communication means 33, 43, and 53. It may be a signal to transmit, or may be a null frame having a length of two frames directly generated by the first wireless communication means 23 side.

In the former case, the time taken for reserving the second to fourth CEC buses is short, and the reason for reserving the second frame section is described above.

After reserving the two frames in this way, the length of the total CEC message and the destination are known, so that the first wireless communication means 23 transmits the CEC message to the third device 41 where the CEC message will arrive, and the second Alternatively, the fourth device 31 or 51 transmits a second reservation signal to reserve the second CEC bus and the fourth CEC bus by N frame lengths corresponding to the total length of the CEC message.

Here, the second reservation signal generates a N-frame length null frame at the second wireless communication means 33 and the fourth wireless communication means 53, so that the second CEC bus 32 and the fourth CEC bus 52 ) Is a signal to send each.

When a stable CEC bus without a collision of CEC information is implemented wirelessly, detailed information and user electronic control of each multimedia device connected to the HDMI cluster can be obtained through the actual CEC bus implemented wirelessly.

According to the present invention, it is possible to establish a wireless HDMI interface environment without restrictions on device mobility and hassle of cable installation, and it is possible to transmit stable CEC information even under a wireless HDMI environment, thereby providing the same performance as a wired repeater without additional costs. A virtual repeater can be implemented.

Claims (14)

In the HDMI-based system consisting of N devices and N wireless communication means connected to the N devices, respectively, A first device of the N devices; And A first wireless communication means of said N wireless communication means connected to said first device, Here, the first wireless communication means, Between the second wireless communication means of the N wireless communication means connected to the second one of the N devices and the audio / video signal, and the wireless communication of the audio / video signal. Perform wireless communication with the remaining wireless communication means except for the first one of the N wireless communication means to update the information including the location and the radio address of the remaining devices except the first one of the devices; , The N is a natural number, the wireless interface device of HDMI. The wireless interface device of claim 1, wherein the wireless communication of the HDMI audio / video signal uses directional mmWave. A wireless interface apparatus of HDMI having N CEC buses and N wireless communication means connected to the N CEC buses, respectively, A first CEC bus of the N CEC buses; And A first wireless communication means of said N wireless communication means connected to said first CEC bus, Here, the first wireless communication means, Upon detecting a CEC signal, a first reservation signal for reserving the remaining CEC buses other than the first CEC bus among the N CEC buses is transferred to the remaining wireless communication means except for the first wireless communication means of the N wireless communication means. A second time corresponding to the length of the CEC signal on the first CEC bus among the N CEC buses and the remaining CEC buses except for the CEC bus. Send a reservation signal, The N is a natural number, the wireless interface device of HDMI. The method of claim 3, And the first reservation signal is a signal for reserving the remaining CEC buses except for the first CEC bus of the N CEC buses for two CEC frames. The signal of claim 4, wherein the signal for reserving the remaining CEC buses except for the first CEC bus of the N CEC buses during the 2 CEC frames is: A null frame having a length of 2 CEC frames is generated on the other side of the N wireless communication means except for the first one of the N wireless communication means, so that the remaining CEC buses except the first CEC bus of the N CEC buses are generated. HDMI interface device, characterized in that the signal to transmit. The signal of claim 4, wherein the signal for reserving the remaining CEC bus except for the first CEC bus of the N CEC buses during the 2 CEC frames is: And a null frame signal having a length of 2 CEC frames generated by the first radio communication means. The method of claim 3, wherein the first wireless communication means, And after transmitting a CEC signal, a null frame is transmitted to the first CEC bus. In the air interface method of the HDMI-based system consisting of N devices and N wireless communication means connected to each of the N devices, A first wireless communication means of said N wireless communication means connected to a first one of said N devices is connected to a second wireless communication means of said N wireless communication means connected to a second device of said N devices; Between the wireless communication of the audio / video signal and the wireless communication of the audio / video signal, in order to update the information including the location and the radio address of the remaining devices except the first one of the N devices; And performing wireless communication with the remaining wireless communication means except for the first wireless communication means of the N wireless communication means, The N is a natural number, the wireless interface method of HDMI. The wireless interface method of claim 8, wherein the wireless communication of the audio / video signal uses directional mmWave. A wireless interface method of HDMI having N CEC buses and N wireless communication means connected to the N CEC buses, respectively, The first one of the N wireless communication means detects the CEC signal of the first CEC bus of the N CEC buses and reserves the remaining CEC buses except for the first CEC bus of the N CEC buses. Transmitting a first reservation signal to the remaining wireless communication means other than the first wireless communication means of the N wireless communication means; And After a predetermined time, the first wireless communication means transmits the CEC signal to the corresponding wireless communication means, and the first wireless communication means of the N wireless communication means and the remaining wireless communication means except for the corresponding wireless communication means. Transmitting a second reservation signal corresponding to the length of the CEC signal; The N is a natural number, the wireless interface method of HDMI. The method of claim 10, And the first reservation signal is a signal for reserving the remaining CEC buses except for the first CEC bus of the N CEC buses for two CEC frames. The signal of claim 11, wherein the signal for reserving the remaining CEC bus except for the first CEC bus of the N CEC buses during the 2 CEC frames is: A null frame having a length of 2 CEC frames is generated on the other side of the N wireless communication means except for the first one of the N wireless communication means, so that the remaining CEC buses except the first CEC bus of the N CEC buses are generated. HDMI wireless interface method characterized in that the signal to transmit. The signal of claim 11, wherein the signal for reserving the remaining CEC bus except for the first CEC bus of the N CEC buses during the 2 CEC frames is: And a null frame signal having a length of 2 CEC frames generated by the first radio communication means. The method of claim 10, And the first wireless communication means transmits a null frame to the first CEC bus after transmitting the second reservation signal.

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