KR100481529B1 - Wireless communication apparatus capable of connectionless oriented broadcast and method thereof - Google Patents

Abstract

Disclosed are a wireless communication apparatus capable of connectionless oriented broadcast and a method thereof. The wireless communication apparatus includes a transceiver for transmitting and receiving data with an external device, a synchronization information generation unit for generating synchronization information for synchronization with an external device, a packet generation unit for generating a broadcast data packet including broadcast information, and And a controller for broadcasting the synchronization information through the transceiver to synchronize the channel with the external device and then transmitting the broadcast data packet to the external device through the transceiver. As a result, broadcast information can be quickly transmitted to an external device without wasting time passing through the connection setup procedure.

Description

Wireless communication apparatus capable of broadcast without connection and its method {wireless communication apparatus capable of connectionless oriented broadcast and method

The present invention relates to a wireless communication device capable of connectionless oriented broadcast and a method thereof, and more particularly, to a connectionless oriented broadcast that can transmit broadcast information before a connection establishment procedure in a Bluetooth system. The present invention relates to a wireless communication apparatus and a method thereof.

Bluetooth was originally developed to eliminate the cables that connect devices such as mobile phone handsets, headsets, and portable computers. It is a low-cost, low-power, short-range wireless technology. However, by enabling standardized wireless communication between Bluetooth devices, Bluetooth has created the concept of a personal area network (PAN), which is a kind of short-range wireless network.

Bluetooth operates using the 2.4GHz unlicensed Industrial, Scientific and Medical (ISM) band, and the Bluetooth device that initiates data exchange in the network that Bluetooth creates is called the master, and the Bluetooth device that responds to the master is called a slave. One master can connect with up to seven active slaves. Thus, a network formed by connecting one or more slaves to one master is called a piconet.

On the other hand, Bluetooth terminals that support the Bluetooth PAN profile (PAN User: PANU) needs to collect location information from Bluetooth network access devices (hereinafter referred to as "NAP"). In addition, as the number of Bluetooth terminals that one NAP is responsible for varies as the Bluetooth terminals move, the NAPs periodically transmit information of Open System Interconnection (OSI) Layer 2 (Data link layer) and Layer 3 (Network layer). It is necessary to broadcast. According to the Bluetooth standard document, Bluetooth is a connection-oriented method that takes a lot of time to set up a connection such as inquiry, inquiry scan, page, page scan, etc. before data transmission. connection oriented) system. Therefore, transmission of information through broadcast is also possible only after the connection setup is completed between Bluetooth devices constituting one piconet.

In addition, Bluetooth terminals use a lot of radio resources for the handover (handover) that occurs when moving from one piconet to another. For example, in voluntary handover, some NAPs must perform a calling procedure for handover to only one Bluetooth terminal. During this call process, NAPs must interrupt the service for a long time for Bluetooth devices that are connected and receiving services. This interruption of service makes it impossible to support real-time services. However, since most Bluetooth terminals are in an idle state, performing a handover every time the Bluetooth terminal moves is a waste of resources. This is because it is enough for NAP to know the approximate location of the Bluetooth terminal in the idle state.

The Bluetooth PAN Working Group or the Local Positioning Working Group addresses the need for much information to be exchanged and broadcast before the master and slave are determined. However, as described above, in order to broadcast information in a Bluetooth system, since a piconet consisting of a master and a slave is possible only under a determined situation, a method for supporting broadcast before a connection establishment procedure is required.

To this end, Philips has proposed a way to extend the ID packet to broadcast local position during the inquiry process. However, this method causes a problem when broadcast information is delivered in pieces. That is, the location information included in the extended ID packet (hereinafter referred to as 'EID packet') is 300 bytes, and the access point is periodically advertised by the IP layer handover protocol. However, there is a problem in how to efficiently arrange such broadcast messages.

The Philips proposal also has the problem of spending too much time because each slot packet must be repeated every 16 hopping frequencies. In addition, since receiving EID packet synchronizes with NAP and needs to receive information, even if only one packet is received incorrectly, the information contained in the packet is lost, compared to the case of receiving information after synchronization. Assembly is impossible.

To solve this problem, Widcomm proposed a method of adding a Bluetooth device address (hereinafter referred to as 'BD_ADDR') of the NAP to the extended ID packet. According to this, the Bluetooth terminal receiving the extended ID packet can synchronize with the corresponding NAP using the BD_ADDR and the clock information included in the extended ID packet, thereby supporting fast handover.

However, even in this method, since the Bluetooth terminal must perform a response to the ID packet received to establish a connection, there is a problem that it still takes a long time until the data transmission is possible.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and an object of the present invention is to provide a connectionless wireless communication apparatus and method capable of broadcasting information prior to a connection establishment procedure in a Bluetooth system. In providing.

In accordance with an aspect of the present invention, there is provided a wireless communication apparatus capable of connectionless connection, comprising: a transceiver for transmitting and receiving data with an external device, a synchronization information generation unit for generating synchronization information for synchronization with the external device, A packet generator for generating a broadcast data packet including broadcast information, and synchronizing the channel with the external device by broadcasting the synchronization information through the transceiver, and then transmitting the broadcast data packet through the transceiver. And a control unit for transmitting to an external device.

Here, it is preferable that the synchronization information and the broadcast data packet are transmitted through a beacon window and a broadcast window, respectively. The synchronization information is delivered by an Extended IDentifier (EID) packet, and the EIDE packet is preferably configured to include DIAC, Bluetooth device address, and clock information.

Preferably, the EIDE packet further includes the broadcast window setting information, and the broadcast window setting information includes at least one of an offset slot, a broadcast window size, and a broadcast repetition number. . In addition, the broadcast data packet is preferably configured to include a broadcast information layer, a packet size, and a payload.

The transceiver may transmit / receive data with the external device using a Bluetooth protocol.

On the other hand, in a wireless communication method capable of connectionless broadcast of the present invention, (a) generating a broadcast data packet including synchronization information for synchronization with the external device, and broadcast information, (b) the synchronization information Synchronizing a channel with the external device by broadcasting a message, and (c) transmitting the broadcast data packet to the external device.

Here, it is preferable that the synchronization information and the broadcast data packet are transmitted through a beacon window and a broadcast window, respectively. The synchronization information is delivered by an Extended IDentifier (EID) packet, and the EIDE packet is preferably configured to include a DIAC, a Bluetooth device address, and clock information.

Preferably, the EIDE packet further includes the broadcast window setting information, and the broadcast window setting information is configured to include at least one of an offset slot, a broadcast window size, and a broadcast repetition number. In addition, the broadcast data packet is preferably configured to include a broadcast information layer, a packet size, and a payload.

And, in the steps (a) and (b), it is possible to transmit and receive data with the external device using the Bluetooth protocol.

Hereinafter, with reference to the drawings will be described the present invention in more detail.

1 is a schematic block diagram of a wireless communication device according to the present invention.

The radio communication apparatus 1 includes a control unit 10, a broadcast data packet generation unit 20, a synchronization information generation unit 30, and a transmission / reception unit 40. The wireless communication device 1 having such a configuration communicates with the external device 50 using the Bluetooth protocol.

The synchronization information generation unit 30 in the wireless communication device 1 generates synchronization information for channel synchronization, and the broadcast data packet generation unit 20 generates a broadcast data packet including broadcast information. The transceiver 40 transmits and receives data to and from the external device 50 by the Bluetooth protocol. The control unit 10 broadcasts the synchronization information generated by the synchronization information generation unit 30 through the transmission and reception unit 40, and after transmitting the synchronization information, transmits the broadcast data packet through the transmission and reception unit 40 to an external device ( 50). The external device 50 is a device capable of communicating by a Bluetooth protocol, such as a Bluetooth terminal.

2 shows a hierarchical structure and time information of a broadcast channel.

The radio communication apparatus 1 according to the present invention uses a connectionless broadcast channel. As shown in Fig. 2, the broadcast channel is composed of a beacon window and a broadcast window. Here, the beacon window is used to synchronize channel synchronization between Bluetooth terminals as described in the existing Bluetooth standard document, and the broadcast window is used to deliver broadcast information. The Bluetooth terminal for receiving broadcast information only needs to be in an inquiry scan state. In the beacon window, a similar procedure to the inquiry is performed. Broadcast information transmitted during the broadcast window is transmitted through the same procedure as when broadcast in one piconet.

The synchronization process in the beacon window is performed using an Extended Identifier (EID) packet proposed by Philips. The EDI packet uses a newly defined dedicated inquiry access code (DIAC) as an access code to distinguish it from a general ID packet. The access code is used to detect the presence of a packet and deliver the packet to a specific device. A Bluetooth packet basically consists of an access code, a packet header, and a payload.

Table 1 below shows information included in an EID packet.

      field           Item   size          Remarks  service  Service type  4 bit Synchronization Packet and Random Access Request Packet (2-bit reserved)  synchronization  Clock BD_ADDR  28 bit 32 bit  Broadcast window settings  Offset Slot Broadcast Window Size Broadcast Repeats  12 bits 5 bits  3 bit Selective  Error check  CRC  8 bit FEC rate 2/3

In the items of Table 1, the service type, the clock, and the BD_ADDR are items included in the EID packet. However, the offset slot may be omitted if the broadcast window is continuous after the beacon window, and other parameters may be selectively used as necessary.

The broadcast data packet used in the broadcast window, which starts after the beacon window, has a class of broadcast information, a packet size, and a pay page, as shown in FIG. It consists of fields of payload. In the broadcast information layer field, information such as an LP service, a PAN service, a MANET notification, a reserved, and the like are stored, and the length of the transmitted packet is stored in bytes in the packet size. The payload is changed according to the information stored in the broadcast information layer field.

That is, the broadcast information delivered in the broadcast window may vary depending on the application used. For example, location information may be delivered through broadcast information, and an announcement message used by OSI layer 2 and layer 3 may be delivered. If there is no broadcast information to be delivered, it is also possible to omit the broadcast window.

Such broadcast data packets are divided into appropriate sizes in the Bluetooth Logical Link Control and Adaptation Protocol (L2CAP) layer, processed in the form of ACL data packets, and transmitted through the Bluetooth baseband layer. Here, L2CAP provides the convenience necessary for higher layer protocols to communicate over the Bluetooth link. The baseband performs functions such as channel encoding and decoding, low-level control of timing, and link management within a single data packet transmission area, and adds address fields and link control fields to pure payload data and detects errors. And correction functions.

In the broadcast data packet, the channel access code portion does not need to be newly defined because the received Bluetooth terminal can derive the LAP (Low Address Part) of the BD_ADDR included in the EID packet. .

3 is a flowchart illustrating an operation method of a wireless communication device d capable of connectionless oriented broadcasting according to the present invention.

Referring to the flowchart, the synchronization information generation unit 30 generates an EID packet including synchronization information for channel synchronization, and the broadcast data packet generation unit 20 generates a broadcast data packet (S100). The control unit 10 transmits the EID packet through the beacon window (S110). When the channel is synchronized with the Bluetooth terminal, which is the external device 50, by the transmission of the EID packet, the controller 10 again transmits the broadcast data packet including the broadcast information through the broadcast window (S120). During the beacon window and the broadcast window, the Bluetooth device, such as the external device 50, does not need to send a response to any received packet, and thus does not require the existing fluteus connection setup procedure. Therefore, the broadcast channel used by the wireless communication device according to the present invention has a connectionless characteristic.

4 is a flowchart illustrating a process of transmitting broadcast information between a NAP and a Bluetooth terminal using a wireless communication method according to the present invention.

Referring to the flowchart, the NAP behaves like an inquiry substate in a beacon window, using EID packet trains A and B similar to the inquiry procedure. The Bluetooth terminal in the inquiry scan mode holds one hopping frequency and determines that the beacon window is started when the EID packet is received (S200). If the general ID packet is received instead of the EID packet, the Bluetooth terminal recognizes the general inquiry procedure and performs the corresponding procedure (S250 and S260).

The Bluetooth terminal receiving the EID packet is synchronized with the BD_ADDR included in the received EID packet and clock information (S210). In addition, the Bluetooth terminal determines the start time and size of the broadcast window by using the offset slot and the broadcast window size included in the EID packet (S220).

Once the NID and the Bluetooth terminal are synchronized by the EID packet transmitted from the beacon window, the Bluetooth terminal operates as a slave in one piconet (S230). At this time, the master becomes NAP. The synchronized Bluetooth terminal receives the broadcast data packet transmitted through the broadcast window (S240). As a result, broadcast information is transmitted to the Bluetooth terminal. NAP and Bluetooth terminals that participated in the broadcast channel return to their original state when the broadcast window ends.

Synchronous NAP and Bluetooth terminals also match frequency hopping patterns, so Asynchronous Connectionless (ASL) data packets can be used to send broadcast information. In this case, one packet may be sent many times, and the Bluetooth terminal may receive and reassemble the divided ACL data packets. Furthermore, the Bluetooth terminal may discard broadcast information that cannot be understood. In addition, the broadcast channel may also support the SCO service if a lookup slot and a broadcast data slot are processed using a synchronous reverse slot (SCO) reverse slot.

In the above embodiment, since the Bluetooth terminal does not need to perform a separate connection setup procedure, the DIAC supporting the broadcast channel even in any of sniff mode, hold mode, park mode, and active mode. Received to synchronize with the corresponding NAP, and can then receive broadcast information. By using this feature, one Bluetooth terminal can receive information from several NAPs, and can quickly perform a handover procedure using the received information.

In addition, since the present invention uses DIAC newly defined in the EID packet, the general Bluetooth device does not affect the existing Bluetooth communication by discarding the packet without any response. In addition, if the wireless communication device according to the present invention receives a general inquiry message during the beacon window, the wireless communication device performs an operation corresponding to the existing Bluetooth protocol, and thus does not cause any problem in communication with the Bluetooth device that complies with the existing Bluetooth protocol.

As described above, according to the present invention, the broadcast channel including the beacon window and the broadcast window can be used to broadcast information without going through a connection establishment procedure. Accordingly, broadcast information can be quickly delivered without wasting time required for the connection establishment procedure.

In addition, although the preferred embodiment of the present invention has been shown and described above, the present invention is not limited to the specific embodiments described above, but the technical field to which the invention belongs without departing from the spirit of the invention claimed in the claims. Of course, various modifications can be made by those skilled in the art, and these modifications should not be individually understood from the technical spirit or the prospect of the present invention.

1 is a block diagram schematically showing a wireless communication device according to the present invention;

2 illustrates a hierarchical structure and time information of a broadcast channel;

3 is a flowchart provided to explain an operating method of a wireless communication device according to the present invention; and

4 is a flowchart provided to explain a process of transmitting brocast information between a NAP and a Bluetooth terminal using a wireless communication method according to the present invention.

Explanation of symbols on the main parts of the drawings

10: control unit 20: broadcast data packet generation unit

30: synchronization information generator 40: transceiver

50: external device

Claims (16)

Transmitting and receiving unit for transmitting and receiving data with an external device; A synchronization information generator for generating synchronization information for synchronization with the external device; A packet generation unit generating a broadcast data packet including broadcast information; And And a controller for broadcasting the synchronization information through the transceiver to synchronize a channel with the external device and then transmitting the broadcast data packet to the external device through the transceiver. A wireless communication device capable of broadcasting. The method of claim 1, And the synchronization information and the broadcast data packet are transmitted through a beacon window and a broadcast window, respectively. The method of claim 2, And the synchronization information is transmitted by an Extended IDentifier (EID) packet. The method of claim 3, The EIDE packet may include a dedicated inquiry access code (DIAC), a Bluetooth device address, and clock information. The method of claim 4, wherein And the EID packet further comprises the broadcast window setting information. The method of claim 5, The broadcast window setting information may include at least one of an offset slot, a broadcast window size, and a broadcast repetition number. The method of claim 2, And the broadcast data packet includes a broadcast information layer, a packet size, and a payload. The method of claim 1, The transmission and reception unit is a wireless communication device capable of connection-free broadcast, characterized in that for transmitting and receiving data with the external device using a Bluetooth protocol. (a) generating a broadcast data packet including synchronization information for synchronization with an external device and broadcast information; (b) synchronizing a channel with the external device by broadcasting the synchronization information; And (c) transmitting the broadcast data packet to the external device. The method of claim 9, And the synchronization information and the broadcast data packet are transmitted through a beacon window and a broadcast window, respectively. The method of claim 10, The synchronization information is wireless communication method capable of a connectionless-oriented broadcast, characterized in that it is delivered by an Extended IDentifier (EID) packet. The method of claim 11, The EIDE packet may include a dedicated inquiry access code (DIAC), a Bluetooth device address, and clock information. The method of claim 12, And the EID packet further includes the broadcast window setting information. The method of claim 13, The broadcast window setting information may include at least one of an offset slot, a broadcast window size, and a broadcast repetition number. The method of claim 10, And the broadcast data packet comprises a broadcast information layer, a packet size, and a payload. The method of claim 15, Step (a) and (b), the wireless communication method capable of connection-free broadcast, characterized in that for transmitting and receiving data with the external device using a Bluetooth protocol.