KR20080021456A - Method of sending message for interface in communication system - Google Patents

Abstract

The present invention relates to a message transmission method for an interface between a wired network and a wireless network or devices. In the message transmission method according to the present invention, in a message transmission method for an interface between a wired network and a wireless network, each bit constituting a first message received from the wired network is broadcast on the wireless network in units of bits. And receiving an acknowledgment signal (ACK / NACK) for the entire first message from a specific device of the wireless network, and transmitting the acknowledgment signal to the wired network. Can be.

Description

Method of transmitting a message for interfacing networks or devices

1 illustrates an example of a configuration of a communication system in which a wired network and a wireless network are connected.

2 shows an example of the configuration of the WVAN.

3 is a view for explaining the frequency band of the HRP channel and LRP channels used in the WVAN.

4 is a system configuration diagram according to an embodiment of the present invention.

5A illustrates the data format of a CEC message used in an HDMI system.

5B shows the data format of the header block.

6 shows a pulse format of each bit constituting a CEC message.

7 shows the structure of a system according to a preferred embodiment of the present invention.

8 is a view for explaining a preferred embodiment according to the present invention.

FIG. 9 is a view for explaining a technical feature of an embodiment of the present invention described with reference to FIG. 8 more easily.

10 shows the structure of a system according to another preferred embodiment of the present invention.

The present invention relates to an interface between a network or a device, and more particularly, to a message transmission method for an interface between a wired network and a wireless network or devices.

Recently, due to the development of communication, computer and networking technology, many kinds of networks have been developed and implemented in real life. Networks exist in large networks that connect the world, such as wired or wireless Internet, while small wired or wireless networks exist that connect home appliances in confined spaces such as homes or workplaces. As the types of networks are diversified, interfacing technologies are also diversified to enable communication between networks and networks or by connecting devices and devices. In particular, it remains one of the technical challenges to effectively connect the wired network and the wireless network in any way to enable smooth communication.

1 illustrates an example of a configuration of a communication system in which a wired network and a wireless network are connected. In FIG. 1, a wired network 10, in which a plurality of devices are connected by wire, and a wireless network 20, in which a plurality of devices are connected via a wireless channel, are connected through an interface device 30 so that different wired or wireless devices are connected. Allow communication between devices in the network. The interface device 30 may be implemented as an independent device that is physically separate from other devices, and may be physically connected to other devices, for example, device D (DEV D) and / or device b (DEV b). It is also possible to implement in the form.

One problem to be solved in the technique of interfacing a wired network with a wireless network is how quickly and efficiently a message transmitted from a wired network to a wireless network can be transmitted. That is, a delay may occur in the process of transmitting a message from the wired network to the wireless network due to the difference in the transmission method according to the wired and wireless transmission as well as using different data formats between the wired network and the wireless network. In particular, when a message is transmitted by using an automatic retransmission (ARQ) technique or a hybrid automatic retransmission (HARQ) technique, a wired network is required because the receiving side must respond with an acknowledgment signal (ACK / NACK). In the process of transmitting a message to a wireless network, more delay may be caused, and the delay caused by this may cause a problem of smooth communication.

The present invention has been made to solve the problems of the prior art as described above, an object of the present invention is to provide a message transmission method for the interface of the wired network and wireless network.

Another object of the present invention is to provide a message transmission method for an interface of two devices.

In one aspect of the present invention, there is provided a message transmission method according to the present invention, wherein in the message transmission method for an interface between a wired network and a wireless network, each bit constituting the first message received from the wired network is expressed in bits. Broadcasting over a wireless network, receiving an acknowledgment signal (ACK / NACK) for the entire first message from a specific device of the wireless network, and transmitting the acknowledgment signal to the wired network. It can be configured to include.

In another aspect of the present invention, the message transmission method according to the present invention, in the message transmission method for the interface of the first device and the second device, each bit constituting the first message received from the first device bit Transmitting the acknowledgment signal (ACK / NACK) for the entire first message from the second device; transmitting the acknowledgment signal to the first device; It may comprise a step.

The construction, operation and other features of the present invention will be readily understood by the embodiments of the present invention described below with reference to the accompanying drawings. An embodiment to be described below is a method for transmitting a message for an interface of a high-definition multimedia interface (HDMI) wired network, which is a type of a wired network, and a wireless video area network (WVAN), which is a type of a wireless private network (WPAN). This is an example applied to. In particular, one embodiment of the present invention relates to a method for transmitting a CEC (Consumer Electronics Control) message from a particular device in an HDMI network to another device in a WVAN.

High-Definition Multimedia Interface (HDMI) is a multimedia interface capable of transmitting uncompressed full digital audio / video. HDMI is an interface between set-top boxes and any audio / video devices such as DVD players, monitors, and digital TVs. Provides a wired interface. HDMI supports multichannel digital audio over a single cable with enhanced high definition video. This means that it can transmit all ATSC HDTVs and 8 channel digital audio with sufficient bandwidth. For a detailed description of HDMI, refer to the HDMI standard document 'High-Definition Multimedia Interface Specification Version 1.2a, Dec. 14, 2005 ".

WVAN is a wireless network that can support uncompressed transmission of 1080p A / V streams by establishing a wireless network between digital devices in a limited space within 10 meters, such as a home, and having a throughput of 4.5 Gbps or more with a bandwidth of about 7 GHz. to be. Because HDMI is a wired network connecting digital devices, WVAN is a network technology that can be used in parallel with HDMI or replace HDMI in the long run.

2 shows an example of the configuration of the WVAN. The WVAN consists of two or more user devices 31 to 35, one of which acts as a coordinator 31. The coordinator 31 serves to provide basic timing of the WVAN, control quality of service (QoS) requirements, and the like. WVAN supports a high-rate physical layer (HRP) and a low-rate physical layer (LRP) as a physical layer. HRP is a physical layer capable of supporting a data rate of 1Gb / s or more, LRP is a physical layer supporting a data rate of several Mb / s. HRP is highly directional and is used for isochronous data streams, asynchronous data, MAC commands and A / V control data transmission over unicast connections. LRP supports either directional or omni-directional modes and is used for sending beacons, asynchronous data and MAC commands via unicast or broadcast.

3 is a view for explaining the frequency band of the HRP channel and LRP channels used in the WVAN. HRP uses four channels with 2.0 GHz bandwidth in the 57-66 GHz band, and LRP uses three channels with 92 MHz bandwidth. As shown in FIG. 3, the HRP channel and the LRP channel share a frequency band and are divided and used by a time divisional multiplexing (TDM) scheme.

4 is a system configuration diagram according to an embodiment of the present invention. 4 shows that the HDMI device 40 and the interface device 50 are connected by the connector 45. The interface device 50 receives the A / V data stream and control information transmitted from the HDMI device 40 and transmits the data to a specific device (not shown) of the WVAN via a wireless interface. It plays a role of connecting WVAN with.

Referring to FIG. 4, the HDMI device 40 includes a main processor 41, an HDMI transport chip 42, and a CEC signaling processor 43. The interface device 50 includes an HDMI receiving chip 51, a format conversion processor 52, a MAC / PHY entity 53, and an RF module 54. Audio and video data and its auxiliary data transmitted from the HDMI transport chip 42 of the HDMI device 40 are transmitted to the HDMI receiver chip 51 of the interface device through three TMDS channels. In FIG. 4, a video pixel clock is transmitted through a TMDS channel clock channel and used as a frequency reference for data recovery on the three TDMS data channels by the HDMI receiving chip 51. The HDMI receiving chip 51 transmits the A / V stream transmitted from the HDMI transmitting chip 42 to the MAC / PHY entity 53. The format conversion processor 52 converts the format of the control information transmitted from the HDMI device 40 and transmits it to the MAC / PHY entity 53. The MAC / PHY entity 53 processes the received data according to a protocol, and the RF module 54 performs radio signals such as radio modulation, up-converting, and signal amplification on the received data. The process is performed to transmit via an antenna (not shown).

5A illustrates the data format of a CEC message used in an HDMI system. The CEC protocol provides high-level control between all kinds of audiovisual devices in a user environment. The main functions of CEC are one touch play, system standby, one touch record and device menu control. For details, refer to the HDMI standard document ' High-Definition Multimedia Interface Specification Version 1.2a, Dec. 14, 2005 ".

Referring to FIG. 5A, an information bits field may include data, an operation code, or address information. The End of Message (EOM) bit is a bit indicating whether or not the corresponding bit is the end of the message, and the ACK (Acknowledge) bit is used to inform whether the message receiving side has received data or a header block. The ACK bit is set to '1' by the source device sending the CEC message, and upon receipt of the CEC message successfully, the destination device sends a '0' to the source device as a received acknowledgment signal (ACK).

5B shows the data format of the header block. The header block consists of an EOM bit, an ACK bit, an 'Initiator' field that identifies the source device that sent the CEC message, and a 'Destination' field that identifies the destination device that should receive the CEC message. The starting bit is located at the front of the header block. The header block can be used as a 'Ping' message to check whether other devices are in an active state. FIG. 6 illustrates a pulse format of each bit constituting the CEC message, wherein (a) is a pulse format of '0' bits, and (b) is a pulse format of '1' bits. The pulse representing one bit is 2.75 ms long.

7 shows the structure of a system according to a preferred embodiment of the present invention. In FIG. 7, the source device 70 and the destination device 100 are interfaced through the first interface device 80 and the second interface device 90. The first interface device 80 and the second interface device 100 may be physically integrated with the source device 70 and the destination device 100, respectively, and are physically separated from each other, such as a connector. It is also possible to connect via. The first interface device 80 and the second interface device 100 communicate with each other via an air interface according to the WVAN protocol. The first interface device 80 includes a CEC interface (I / F) module 81, a higher layer entity 82, and a MAC / PHY layer entity 83, and the second interface device 90 Includes a CEC interface module 92, a higher layer entity 93, and a MAC / PHY layer entity 94. The function of each component of FIG. 7 will be combined with the description of FIG. 8.

8 is a view for explaining a preferred embodiment according to the present invention. FIG. 8 is an embodiment to which the present invention is applied on the system shown in FIG. 7 and is an example of transmitting a ping message from a source device of an HDMI network to a destination device of a WVAN network. 7 and 8, the CEC I / F module 81 of the first interface device 80 converts a CEC message signal from the source device 70 into a binary bit string [S81]. That is, the CEC I / F module 81 converts the CEC message signal received from the source device 70 in the pulse form shown in FIG. 6 into binary data. The upper layer entity 82 of the first interface device 80 transfers each bit constituting the CEC message from the CEC I / F module 81 to the MAC / PHY layer entity 83 immediately after receiving each bit. [S83]. The MAC / PHY layer entity 83 of the first interface device 80 processes each bit received from the upper layer entity 82 according to a protocol of a MAC / PHY layer to broadcast over a wireless channel. [S83]. In this case, the term 'broadcast' means that all devices in the WVAN network should receive each of the broadcast bits. For example, in the MAC / PHY layer, a header is attached to each bit of the CEC message during data processing according to a protocol, and the ID of the transmitting device and the receiving device are transmitted to the header. Included. In this case, when the reception device ID is set to an ID representing all devices and transmitted, the respective bits may be broadcast.

Each bit of the CEC message broadcast from the first interface device 80 is received by the second interface device 90 and is higher layer through the MAC / PHY entity 94 of the first interface device 90. It is passed to entity 93 [S84, S85]. The upper layer entity 93 of the second interface device 90 transmits each bit of the CEC message received from the MAC / PHY entity 94 to the CEC I / F module 92 of the second interface device 90. The CEC I / F module 92 converts each bit of the CEC message into a pulse form and delivers the bits to the destination device 100. The destination device 100 does not transmit ACK / NACK for each bit of the CEC message, but transmits an ACK / NACK signal for the CEC message itself after receiving the EOM bit of the CEC message. The ACK / NACK signal is transmitted to the first interface device 80 through the CEC I / F module 92, the higher layer entity 93, and the PHY / MAC entity 94 of the second interface device 90. [S86]. The first interface device 80 transmits the ACK / NACK received from the second interface device 90 to the source device 70 [S87].

FIG. 9 is a view for explaining a technical feature of an embodiment of the present invention described with reference to FIG. 8 more easily. In FIG. 9, the first interface device 80 transmits the CEC message transmitted from the source device 70 in the form of a frame, compared to the case in which the CEC message is transmitted bit by bit in FIG. 8. . In FIG. 9, in order to transmit the CEC message in units of frames, the first interface device 80 waits until the EOM bit of the CEC message is received from the source device 70, and when the EOM bit is received, the CEC message. Broadcast the entire message in frame form. When the second interface device 90 receives the start bit of the CEC message, the first interface device 80 receives the EOM bit of the CEC message from the source device 70. Since the second interface device 90 transmits the ACK / NACK for the CEC message to the first interface device 80, the second interface device 90 may receive more information than the ACK / NACK transmission timing for the CEC message. It will be late so that the source device 70 cannot receive ACK / NACK.

In the embodiment of FIG. 8, the destination device 100 transmits the CEC to the second interface device 90 immediately after each bit arrives without waiting until the entire CEC message is received from the source device 70. As soon as the reception of the message is completed, the ACK / NACK is available for transmission.

In the embodiments described with reference to FIG. 8, the functional division of the protocol layer of the first interface device and the second interface device is exemplary, and in the application of the actual system, the function of the protocol layer may be changed or integrated. have.

10 shows the structure of a system according to another preferred embodiment of the present invention. The system according to the embodiment of FIG. 10 includes a source device 110, an interface device 120, and a destination device 130. The difference from FIG. 7 is that the second interface device (90 of FIG. 7) is implemented integrated with the destination device 130. That is, in the system of FIG. 7, the function of the CEC IF module 92 of the second interface device 90 is implemented in the processor 131 of the destination device 130, and the upper layer of the second interface device 90 is implemented. The functions of entity 93 and MAC / PHY entity 94 are integrated into and integrated into higher layer entity 132 and MAC / PHY entity 94 of destination device 13, respectively. A description of each component of the system illustrated in FIG. 10 may refer to embodiments described with reference to FIGS. 8 and 9.

Although the above embodiments have been described with reference to an example of interfacing the HDMI network and the WVAN network, the same application is also applicable to the case of interfacing the device connected by wire with the interface device.

Those skilled in the art to which the present invention described above belongs will understand that the present invention can be implemented in other specific forms without changing the technical spirit or essential features. Therefore, the above-described embodiments are to be understood as illustrative in all respects and not as restrictive. The scope of the present invention is shown by the following claims rather than the detailed description, and all changes or modifications derived from the meaning and scope of the claims and their equivalents should be construed as being included in the scope of the present invention. do.

According to the present invention, a delay in transmitting a message between a wired network and a wireless network or between two devices can be prevented, thereby enabling smooth communication.

Claims (5)

In the message transmission method for the interface between a wired network and a wireless network, Broadcasting each bit constituting the first message received from the wired network through the wireless network in units of bits; Receiving an acknowledgment signal (ACK / NACK) for the entire first message from a specific device in the wireless network; And Transmitting the acknowledgment signal to the wired network. The method of claim 2, And the acknowledgment signal for the first message is a reception acknowledgment signal (ACK). The method according to claim 1 or 2, The first message is a message, characterized in that the CEC (Consumer Electronics Control) message. The method of claim 3, The specific device is a destination device of the CEC message. In the message transmission method for the interface between the first device and the second device, Transmitting each bit constituting the first message received from the first device to the second device in units of bits; Receiving an acknowledgment signal (ACK / NACK) for the entire first message from the second device; And Transmitting the acknowledgment signal to the first device.

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