JP2005341148A - Wireless communication method and apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a technology capable of establishing time synchronization without the need for using a particular wireless communication apparatus for a reference in an autonomous distribution adhoc network. <P>SOLUTION: All wireless communication apparatuses take synchronization with their neighboring wireless communication apparatuses in an autonomous and distributing way without adopting a system wherein a particular wireless communication apparatus is used for a master on a network and all the wireless communication apparatuses take synchronization with synchronizing signals of the master. As the processing of taking synchronization with the neighboring wireless communication apparatuses, when correction for a prescribed period is required in addition to temporary time correction for example, a time including a correction amount is periodically set to correct the time. Moreover, each wireless communication apparatus uses a synchronization correction period over a prescribed temporal period to make correction with the neighboring wireless communication apparatuses. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a wireless communication method, a wireless communication apparatus, and an apparatus for performing communication processing in a wireless communication system, which are suitable for application to a wireless local area network (LAN) system that performs data communication, for example. The present invention relates to a computer-readable program implemented, and particularly to a technique applied to an ad hoc network that is an autonomous distributed network in which no base station device is arranged.

  Conventionally, as time synchronization processing for synchronizing the timing of transmission / reception in each wireless communication device constituting a wireless network, for example, a synchronization signal is issued at a predetermined cycle from a specific access point or base station device, and each wireless communication The terminal is provided with a time correction means and a time correction mechanism for correcting or fine-tuning the time managed by the terminal by receiving the synchronization signal and analyzing the reception time. Synchronizing with the station apparatus, all wireless communication terminals are provided with the time correction means and the time correction mechanism, so that the synchronization within the network is achieved.

  In addition, even in an autonomous distributed network where a specific access point or base station device is not arranged in the network, a method is assumed in which a specific wireless communication device called a master is determined and synchronized with the master in a centralized manner. It had been.

  In other words, as a general time synchronization process in a conventional wireless network, the time that all wireless communication devices manage themselves at this timing by notification of the timing from a specific device existing in the network or outside the network. A common method is to synchronize the network.

  Moreover, in the time synchronization processing of the wireless network described in Patent Document 1, in the autonomous distributed network, each node does not receive a reference time from the outside, and further, processing that can establish time synchronization without requiring a network topology. It is disclosed.

Furthermore, recently, processing is also considered in which an autonomous distributed ad hoc network is operated by synchronizing all wireless communication devices existing in the vicinity.
Japanese Patent Laid-Open No. 2003-274349

  As described above, conventionally, a specific wireless communication device is required to perform time synchronization in the network, and a user can freely construct an autonomous decentralized ad hoc network with nearby wireless communication devices. It was a hindrance.

  In addition, in the time synchronization processing of the wireless network described in Patent Document 1, synchronization is performed in order with the master wireless node, and finally synchronization with the wireless master as the entire master is necessary. There was a problem of becoming.

  Furthermore, in the process of simply synchronizing with all the wireless communication devices that exist in the vicinity, synchronization cannot be achieved unless the behavior change in the surrounding wireless communication devices is always grasped. There has been a problem that low power consumption operation for reducing the frequency is difficult.

  In particular, when ad hoc networks that exist asynchronously exist in the same space, there is a problem that each wireless communication device cannot determine which existing ad hoc network should be synchronized.

  In addition, in the conventional process of designating a specific wireless communication device as a master, there is a problem that it takes time to designate a specific communication device as a master unless a communication device as a master is determined from the beginning. .

  Furthermore, when changing the master communication device during the operation of the wireless network, there has been a problem that complicated processing must be performed to reset the master communication device.

  An object of the present invention is to enable time synchronization to be established without using a specific wireless communication device as a reference in an autonomous distributed ad hoc network.

  Another object of the present invention is to satisfactorily establish time synchronization without always monitoring the presence of surrounding wireless communication devices.

  In the present invention, a specific wireless communication device is used as a master on a network, and not all wireless communication devices are synchronized with the synchronization signal, but all wireless communication devices are autonomously distributed among neighboring wireless communication devices. Synchronized.

  As a process to synchronize with neighboring wireless communication devices, when correction is required in a predetermined cycle in addition to temporary time correction, the time that takes the correction amount into account is set periodically to correct the time To do.

  In addition, correction is performed using a synchronization correction period over a predetermined time period with neighboring wireless communication devices.

  By doing in this way, the information which the surrounding radio | wireless communication apparatus transmitted with the predetermined period can be collected in light of own time, and self-synchronization time can be correct | amended from the collected time information.

  According to the present invention, the information transmitted by neighboring wireless communication devices in a predetermined cycle is collected in light of its own time, and the synchronization time is corrected from the collected time information, so that in the ad hoc network Can get time synchronization. Thus, synchronization can be obtained with peripheral communication devices in an autonomous and distributed manner without arranging a control station device or a specific device that controls time synchronization in the network.

  In addition, by performing one time correction of the own synchronization time in a predetermined cycle unit, it is possible to stably achieve time synchronization with peripheral communication devices.

  That is, it is only necessary to perform time correction at a predetermined period without performing time correction every superframe period, so that it is possible to obtain network synchronization that enables low power consumption operation.

  Furthermore, the process of correcting its own clock error each time can be simplified by periodically correcting the synchronization time of itself with a predetermined period.

  Thus, for example, when the self-frame period is constantly short, even if time correction is required every time, the self-clock error is corrected by performing time correction periodically at a predetermined period. The effect is that the number of times can be reduced.

  Hereinafter, an embodiment of the present invention will be described with reference to the accompanying drawings.

  When a communication propagation path assumed in this embodiment is wireless, and a network is constructed between a plurality of devices using a single transmission medium (when a link is not separated by a frequency channel) It is as. However, the same can be said even when a plurality of frequency channels exist as transmission media. Further, the communication assumed in this embodiment is a storage and exchange type traffic, and information is transferred in units of packets. In addition, the network in the present embodiment is an ad hoc network, and there is no control station that manages and manages each communication station in the network.

  FIG. 1 is an arrangement example of radio communication apparatuses (communication stations) constituting the radio communication system according to the present embodiment. Here, seven wireless communication devices 1, 2,... 7 are distributed in the same space.

In FIG. 1, communication ranges 1a, 2a,... 7a capable of wireless communication with each communication device 1, 2,... 7 are indicated by broken lines, and communication with other communication devices within the range is possible. In addition, it is defined as a range in which a signal transmitted by itself interferes. That is, in the example of FIG.
The communication device 1 is in a range where it can communicate with nearby communication devices 2, 3, 4.
The communication device 2 is in a range where communication with the communication devices 1 and 4 in the vicinity is possible.
The communication device 3 is in a range where communication with the communication devices 1, 6, 7 in the vicinity is possible.
The communication device 4 is in a range where it can communicate with nearby communication devices 1, 2, and 5.
The communication device 5 is in a range where communication with the communication device 4 in the vicinity is possible.
The communication device 6 is in a range where communication with the communication device 3 in the vicinity is possible.
The communication device 7 is in a range where communication with the communication device 3 in the vicinity is possible.
In the case of this example, it is assumed that direct wireless communication is not possible between other communication apparatuses. In the specific communication process of this example described later, the process in the case of the network configuration in the wireless communication state shown in FIG. 1 is shown.

  In this embodiment, each communication device performs access control processing using one wireless transmission path in a time-sharing manner with other communication devices in the vicinity in consideration of the influence of each other. In order to perform access control of the wireless communication, each communication device performs time synchronization correction processing.

  FIG. 2 is a block diagram showing a configuration example of a wireless communication apparatus constituting a communication station applied to the system of this example. This wireless communication apparatus includes an interface 24 for exchanging various types of information with a device (not shown) connected to the wireless communication device, and is sent to the interface 24 from the connected device. A data buffer 23 is provided for temporarily storing data and data received via the wireless transmission path.

  The configuration for performing communication with other wireless communication apparatuses existing in the vicinity will be described. The wireless communication apparatus of this example operates in synchronization with the wireless communication apparatuses existing in the vicinity in an autonomous and distributed manner. As a means for wireless communication, an antenna 11 that receives a signal from a peripheral communication device on a transmission medium and transmits a transmission signal of the self-communication device is connected to the wireless reception unit 12 and the wireless transmission unit 22. . The wireless transmission unit 22 performs modulation processing as, for example, an ultra-wideband signal (Ultra Wideband signal: UWB signal), and the wireless reception unit 12 performs demodulation processing of the ultra-wideband signal, for example. Supply to the circuit. As for the antenna 11, separate antennas may be prepared for transmission and reception, or so-called diversity reception may be performed by providing a plurality of antennas.

  The wireless reception unit 12 receives a signal from another communication device at a specified time and performs a decoding process as a predetermined signal format. A signal received by the wireless reception unit 12 is supplied to the reception data analysis unit 13, and a data information portion constructed in a predetermined format is extracted from the received signal. In addition, the signal received by the wireless reception unit 12 is supplied to the beacon analysis unit 14, the beacon signals are collected from the received signals, and the description information is extracted and analyzed.

  In addition, a reference time generation unit 15 that generates a clock signal serving as a reference for the operation time of the wireless communication device at a predetermined interval, and time information collection that collects reception times of beacons transmitted by nearby wireless communication devices as time information Unit 16 and a correction amount calculation unit 17 that calculates its own synchronization time correction amount from time information collected at predetermined intervals. The correction amount data calculated by the correction amount calculation unit 17 is supplied to the central control unit 18 that performs centralized control of the wireless communication devices constituting the autonomous distributed ad hoc network. The central control unit 18 is connected to an information storage unit 25 configured by a memory or the like, and the operation procedure of the communication device is stored in the information storage unit 25 in an execution command form, and scan cycle information, Presence information of the peripheral communication device, beacon transmission time information of the peripheral communication device, correction information of the synchronization time, and the like are stored.

  Further, based on the correction amount calculated by the correction amount calculation unit 17 and the data stored in the information storage unit 25, a process for periodically setting the correction amount of the synchronization time and maintaining the synchronization of the ad hoc network is performed. Synchronization time correction unit 19, timing control unit 20 that performs time adjustment for maintaining synchronization from reference time information and correction time information, and beacon signal that transmits its presence to peripheral communication devices at a certain period And a beacon generator 21 for generating

  The wireless transmission unit 22 modulates the beacon information generated by the beacon generation unit 21 and the application data information supplied from the data buffer 23 into a predetermined signal format.

  Note that the wireless communication apparatus of this example is not required by adding blocks having other functions as necessary in addition to the blocks shown in FIG. 2 or by integrating functions among the blocks described here. A configuration may be adopted in which the resulting blocks are integrated as appropriate.

  Although the UWB system has been described as an example of the wireless communication system here, other various communication systems suitable for relatively short-distance communication that can be applied to, for example, a wireless LAN can also be applied. Specifically, as a method other than the UWB method, an OFDM (Orthogonal Frequency Division Multiplex) method, a CDMA (Code Division Multiple Access) method, or the like is applicable.

  Next, a super frame configuration defined in the ad hoc network of this example will be described with reference to FIG. The super frame configuration of this example is defined by transmitting periodic beacon signals at predetermined time intervals. FIG. 3 shows the transmission state of beacon B in seven communication apparatuses 1 to 7 and the reception state of beacons transmitted from other stations (positions indicated by diagonal lines N1 to N7: the numbers are the communication apparatuses 1 to 1. 7 corresponds to the number 7) individually for each vehicle.

  The superframe of this example is set so that each of the wireless communication devices 1 to 7 sets the superframe configuration independently, and the superframe configuration of the wireless communication devices existing in the vicinity does not overlap with the start timing.

  Specifically, for example, as shown in FIG. 3A, the wireless communication device 1 receives beacon signals (N2, N3, N4) of communication devices 2, 3, and 4 in the vicinity, and those beacon signals. The own beacon signal (B1) is transmitted at a timing that does not overlap with the other, and the period until the next beacon signal transmission timing (B1 ′) is set as its own superframe cycle.

  Further, as shown in FIG. 3B, the communication device 2 can receive the beacon signals (N1, N4) of the communication devices 1 and 4 in the vicinity. As shown in FIG. 3C, the communication device 3 can receive the beacon signals (N1, N6, N7) of the communication devices 1, 6, and 7 in the vicinity thereof. As shown in FIG. 3D, the communication device 4 can receive the beacon signals (N1, N2, and N5) of the communication devices 1, 2, and 5 in the vicinity thereof. As shown in FIG. 3E, the communication device 5 can receive the beacon signal (N4) of the communication device 4 in the vicinity thereof. As shown in FIG. 3F, the communication device 6 can receive the beacon signal (N3) of the communication device 3 in the vicinity thereof. As shown in FIG. 3G, the communication device 7 can receive the beacon signal (N3) of the communication device 3 in the vicinity thereof.

  The beacon signal transmitted from each communication device is configured as shown in FIG. 4, for example. A beacon frame generated as a beacon signal in this example is transmitted from each wireless communication device at a predetermined cycle, and the surrounding communication devices receive the beacon signal to grasp the presence of the communication device.

  As shown in FIG. 4, the beacon frame of this example describes the broadcast address as the designation of the destination communication device, the address indicating the transmission source communication device, the identifier indicating that it is a beacon frame, the attribute information of this communication device, Consists of presence information of other wireless communication devices existing in the vicinity, presence information of preferential use areas, group identifiers, error detection codes, and the like.

  In addition, if necessary information is added to the information shown in FIG. 4, a beacon frame may be added as appropriate and a beacon frame may be deleted if unnecessary information is configured. Also good.

  Next, a description will be given of a time slot configured in a super frame set at the transmission timing of the beacon signal configured as described above. FIG. 5 is a time slot configuration example in an ad hoc network.

  In this time slot configuration, a super frame period defined from its own beacon transmission position is used as a reference, and the super frame divided into, for example, 64 is defined as one time slot.

  The time slot obtained by dividing the superframe into 64 is set for each wireless communication device constituting the ad hoc network from its own beacon transmission position, and the time slot start position with the wireless communication device existing in the vicinity. By synchronizing, it is configured to synchronize the ad hoc network.

  FIG. 5 shows an example of the wireless communication device 1, where its own beacon transmission position exists in the 0th time slot, beacon reception from the communication device 2 is performed in the 16th time slot, and the communication device 3. A configuration is shown in which beacon reception from is performed in the 32nd time slot and beacon reception from the communication device 4 is performed in the 48th time slot.

  In this way, each wireless communication apparatus is configured to manage the presence of a beacon signal of a communication apparatus existing in the vicinity of the wireless communication apparatus by applying it to a time slot based on its own superframe period.

  FIG. 6 is a configuration example of a scan cycle in an ad hoc network. The configuration of this scan cycle is a configuration in which beacon signals of all neighboring communication devices existing around the device are received by performing a reception operation over a superframe cycle once in a predetermined cycle.

  Here, for example, a configuration is shown in which one scan cycle is set for every 100 superframe cycles, and a beacon signal of a neighboring communication device is received each time.

  In other words, the reception operation over the superframe period is performed in the superframe (SF # 0), and the presence of the communication device existing around itself and the clock deviation are determined from the collected beacons.

  Furthermore, in the subsequent superframes (SF # 1 to SF # 99), these existing beacon signals may be received, but the synchronization time correction operation is not performed.

  Then, after the superframe (SF # 99), the superframe period (SF # 0) for performing the beacon scan arrives, and the reception operation over the superframe period is performed again. It is configured to determine the presence of a communication device existing in the network and a clock shift.

  Next, an example of a communication operation in the wireless communication device in the network of this example will be described with reference to the flowchart of FIG. First, after the power is turned on, the wireless communication apparatus of this example sets a superframe period (step S11), and performs a scanning process for neighboring beacons over the period (step S12).

  And the beacon information of the communication apparatus which exists in the neighborhood which was able to be received is collected (step S13), and the position which does not prevent the beacon transmission and reception of the surrounding communication apparatus is set to its own beacon transmission time (timing) (step) Along with S14), a beacon scan cycle is set (step S15).

  Furthermore, when the beacon transmission time (timing) has arrived (step S16), the correction time amount of the superframe period is acquired (step S17), and if there is a correction additional time (step S18), the correction time has elapsed. After waiting (step S19), a beacon frame is transmitted after waiting for the start of its own superframe cycle (step S20). If there is no additional correction time in step S18, the process proceeds directly to step S20 to transmit a beacon frame.

  When the scan frame set in the scan cycle arrives (step S21), the beacon scan processing in the super frame cycle is started (step S22), and the received beacon reception time from the known communication device is collected (step S22). S23).

  Here, if there is a beacon that is delayed or arrived earlier than the predetermined time (step S24), it is determined whether the correction time needs to be set (step S25), and if necessary, the delay amount (or early arrival amount). To the correction time is set (step S26). If there is no delayed beacon or early beacon in step S24, or if it is determined in step S25 that setting of the correction time is unnecessary, the correction time is not set.

  When a beacon is received from a new communication device (step S27), the communication device is registered as a new communication device (step S28), and if no beacon is received from the existing communication device (step S29). ), The registration of the communication device is deleted (step S30). Note that these registration processes are not started unless a new beacon is received and an existing beacon disappears.

  When the transmission data from the application is received by the interface 24 (see FIG. 2) (step S31), the data is stored in the buffer 23 (step S32), and the time (timing) at which transmission to the destination is possible. Is received (step S33), the data is transmitted (step S34).

  Further, when the own reception time (timing) has arrived (step S35), the reception operation is started, and when the self-addressed data is received (step S36), the data is stored in the buffer (step S37). The data is output from the interface to the application (step S38). Note that this processing is not performed when data other than the self-addressed data is received.

  After completion of each series of operations, the process proceeds to step S16. When the beacon transmission time comes again, the process is repeated.

Next, an example in which the synchronization time correction operation is performed in this way will be described.
FIG. 8 shows an example of occurrence of a synchronization time shift in an ad hoc network. Here, an example of a synchronization time correction process in the communication apparatus 1 is shown. FIG. 8A shows the beacon transmission timing from the wireless communication device 1 in time slot # 0.

  FIG. 8B shows the beacon reception operation of the neighboring communication device 2 in the time slot # 16. Here, the beacon signal is received at a time delayed by 3 clocks from the time managed by the communication device 1. It has been shown.

  FIG. 8C shows the beacon reception operation of the neighboring communication device 3 in the time slot # 32. Here, the beacon signal is received at a time two clocks earlier than the time managed by the communication device 1. It is shown that.

  FIG. 8D shows the beacon reception operation of the neighboring communication device 4 in the time slot # 48. Here, the beacon signal is received at a time delayed by two clocks from the time managed by the communication device 1. It has been shown.

  FIG. 9 is a diagram illustrating a processing example of the synchronization time correction in the wireless communication device when detected in this way. This is because the operation clock of the communication device 1 is corrected based on the collection result of the synchronization time lag information in the wireless communication device 1 shown in FIG. The work is done together.

  Here, from the collection result of the synchronization time lag information in FIG. 8, for example, 3 clocks are corrected per superframe in accordance with the time of the delayed neighboring communication device 2 shown in FIG. The amount of time is added for synchronization. That is, the wireless communication apparatus 1 represents a configuration in which the time slot # 0 is started by adding an additional time correction of 3 clocks after the elapse of its own time slot # 63.

  FIG. 10 shows a processing example of time correction based on the beacon period. In this example, the superframe cycle is adjusted only once in the scan cycle, and a beacon scan is performed in the superframe cycle of SF # 0, where the additional time correction amount is calculated from the beacon transmission time of the neighboring wireless communication device. It shows the process of calculating and correcting the synchronization time between SF # 1 and SF # 2 of the subsequent superframe.

  In this correction operation, a beacon scan is also performed in the superframe period of SF # 0 in the next scan period, and the synchronization time is corrected between SF # 1 and SF # 2 in the subsequent superframes. It will be.

  FIG. 11 shows an example of time correction processing in the superframe period. This is a process of adjusting the time every superframe period, and after performing a beacon scan in the superframe period of SF # 0, if correction is required every superframe period, the subsequent superframe The synchronization time is corrected every time.

  In this correction operation, a beacon scan is also performed in the superframe cycle of SF # 0 in the next scan cycle, and the synchronization time is corrected at intervals of the subsequent superframe as necessary.

  As shown in FIG. 11, the correction time correction may not be performed every superframe period, but may be performed once every predetermined superframe period. For example, if a total of 25 clock corrections are required in 100 superframe periods, the correction may be performed once every 4 superframe periods, one clock at a time.

  Further, in the examples shown in FIGS. 9 to 11, the processing example in the case where the time difference is the most delayed timing as shown in FIG. 8B has been described. However, for example, as shown in FIG. 8C, when it is the timing of early arrival, the correction time amount may be subtracted to achieve synchronization.

  12 to 15 are diagrams showing an example of processing in this case. As a result of collecting the synchronization time lag information, the state shown in FIG. 12 is obtained, and the operation clock of its own communication device is corrected, and synchronization work is performed autonomously and distributedly with surrounding wireless communication devices. Is. Here, from the collection result of the synchronization time lag information in FIG. 12, for example, in accordance with the time of the nearest neighbor communication device 3, for example, a correction time amount of 2 clocks is subtracted per superframe to achieve synchronization. It is a processing example.

  That is, the wireless communication device 1 represents a configuration in which time slot # 0 is started by performing time subtraction correction of 2 clocks in its own time slot # 63.

  FIG. 13 shows a processing example of time subtraction correction based on the beacon period. Here, it is a process to adjust the superframe cycle only once in the scan cycle, and a beacon scan is performed in the superframe cycle of SF # 0, and the subtraction time correction amount is calculated from the beacon transmission time of the neighboring wireless communication device. The process of correcting the synchronization time between SF # 1 and SF # 2 of the subsequent superframe is shown.

  In this correction operation, a beacon scan is also performed in the superframe period of SF # 0 in the next scan period, and the synchronization time is corrected between SF # 1 and SF # 2 in the subsequent superframes. It will be.

  FIG. 14 shows a processing example of time subtraction correction in the superframe period. This is a process of adjusting the time every superframe period, and after performing a beacon scan at the superframe period of SF # 0, if correction is required every superframe period, the super The synchronization time is corrected every frame period.

  This correction operation may be configured such that a beacon scan is also performed in the super frame period of SF # 0 in the next scan period, and the synchronization time is corrected at intervals of subsequent super frames as necessary. .

  FIG. 15 shows an example of time correction processing once in a plurality of superframe periods. Here, an example of processing for adjusting the time once every two frames is shown, but when correction of one clock is required for several superframes, synchronization is performed every predetermined superframe period. Time correction will be performed.

  This correction operation may be configured such that a beacon scan is also performed in the super frame period of SF # 0 in the next scan period, and the synchronization time is corrected at intervals of subsequent super frames as necessary. .

  In the above-described embodiment, the example in which the wireless communication device is configured as the dedicated communication device that performs transmission and reception shown in FIG. 2 has been described. However, for example, the present invention is applied to a personal computer device that performs various data processing. Software that executes the communication control process by causing the computer device side to execute the communication control process after mounting a board or a card that performs the communication process corresponding to the transmission unit or the reception unit in the example ( A computer-readable program) may be implemented on a personal computer device. The program installed in the data processing device such as the personal computer device may be distributed via various recording (storage) media such as an optical disk and a memory card, or distributed via communication means such as the Internet. Also good.

It is explanatory drawing which shows an example of the wireless network structure by one embodiment of this invention. It is a block diagram which shows the structural example of the radio | wireless communication apparatus by one embodiment of this invention. It is a timing diagram which shows the example of a transmission super-frame structure by one embodiment of this invention. It is a block diagram which shows the example of the beacon frame by one embodiment of this invention. It is a timing diagram which shows the example of a time slot structure by one embodiment of this invention. It is a timing diagram which shows the example of the scanning period by one embodiment of this invention. It is a flowchart which shows the example of a radio | wireless communication process by one embodiment of this invention. It is a timing diagram which shows the example of generation | occurrence | production of the synchronous time shift by one embodiment of this invention. It is a timing diagram which shows the example of a synchronous time correction | amendment process by one embodiment of this invention. It is a timing diagram which shows the example of time correction by the beacon period by one embodiment of this invention. It is a timing diagram which shows the example of time correction by the super-frame period by one embodiment of this invention. It is a timing diagram which shows the other example of a synchronous time correction process by one embodiment of this invention. It is a timing diagram which shows the other example of time correction by the beacon period by one embodiment of this invention. It is a timing diagram which shows the other example of time correction by the super-frame period by one embodiment of this invention. FIG. 6 is a timing diagram illustrating an example of time correction using a plurality of superframe periods according to an embodiment of the present invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1-7 ... Wireless communication apparatus (communication station), 1a-7a ... Communication area of wireless communication apparatus, 11 ... Antenna, 12 ... Radio reception part, 13 ... Reception data analysis part, 14 ... Beacon analysis part, 15 ... Standard Time generation unit, 16 ... time information collection unit, 17 ... correction amount calculation unit, 18 ... central control unit, 19 ... synchronization time correction unit, 20 ... timing control unit, 21 ... beacon generation unit, 22 ... wireless transmission unit, 23 ... data buffer, 24 ... interface

Claims (9)

In a wireless communication method for performing wireless communication on an ad hoc network,
Receiving information transmitted from neighboring wireless communication devices at a predetermined period;
Collecting the reception time of the information received in the step against the own time;
Calculating a correction amount of the own synchronization time from the collected time information;
A wireless communication method comprising a step of correcting its own synchronization time based on the correction amount. The wireless communication method according to claim 1,
A wireless communication method having a time correction step of correcting the synchronization time once in a predetermined cycle unit as the step of correcting the synchronization time. The wireless communication method according to claim 1,
A wireless communication method further comprising a time correction step for correcting the synchronization time of the device periodically at a predetermined cycle. In a wireless communication device that performs wireless communication with other wireless communication devices constituting an ad hoc network,
Neighboring communication device information receiving means for receiving information transmitted from other wireless communication devices at a predetermined cycle;
Time information collecting means for collecting the reception time of the information received by the receiving means in light of its own time;
Correction calculating means for calculating a correction amount of the own synchronization time from the time information collected by the collecting means;
A wireless communication apparatus comprising: a time correction unit that corrects its own time based on the correction amount calculated by the correction calculation unit. The wireless communication device according to claim 4, wherein
The time correction means is a wireless communication apparatus that corrects its own synchronization time once in a predetermined cycle. The wireless communication device according to claim 4, wherein
The said time correction means is a radio | wireless communication apparatus which carries out the time correction | amendment of the own synchronous time periodically with a predetermined period. In a computer readable program for executing wireless communication processing in a wireless communication system that performs wireless communication in an ad hoc network,
Receive neighboring communication device information to receive information transmitted from other wireless communication devices in a predetermined cycle,
Collect time information collected by comparing the reception time of the received information with its own time,
Calculating a correction amount of the own synchronization time from the collected time information;
A computer-readable program for executing a process of correcting its own time based on the correction amount. The computer-readable program according to claim 7,
The correction is a computer-readable program that performs one time correction of the self-synchronization time in a predetermined cycle unit. The computer-readable program according to claim 7,
The correction is a computer readable program that performs time correction of its own synchronization time periodically in a predetermined cycle.

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