JP2009130530A - Radio communication apparatus, radio communication method, program, and radio communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a radio communication apparatus, a radio communication method, a program, and a radio communication system. <P>SOLUTION: The radio communication apparatus 10 for cyclically repeating a prescribed frequency hopping pattern and transmitting radio signals in a prescribed transmission time zone is provided with: a reception part for receiving the radio signals transmitted utilizing the frequency hopping pattern from the surrounding radio communication apparatus; a detection part for detecting the start timing of the frequency hopping pattern of the radio signals transmitted from the surrounding radio communication apparatus from the radio signals received by the reception part; and a setting part for setting the start timing of the frequency hopping pattern of the radio signals transmitted in the transmission time zone to the timing with a difference from the start timing detected by the detection part. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a wireless communication device, a wireless communication method, a program, and a wireless communication system.

  According to the WiMedia Distributed MAC layer standard, a technique is described in which a plurality of wireless communication devices form a wireless network by transmitting and receiving wireless signals by sequentially switching a frequency band to be used among a plurality of frequency bands. ing. The frequency band switching pattern may be referred to as a TFC code or a frequency hopping pattern.

  In addition, as a technique for managing communication by each wireless communication device, there is a DRP (Distributed Reservation Protocol) reservation method, a PCA method (Primorized Contention Access) similar to a carrier detection multiple access / collision avoidance method (CAMA / CA method), and the like. Proposed.

  In the DRP reservation method, for example, as described in Patent Document 1, a wireless communication device notifies a slot that can be used with a surrounding wireless communication device, and an available slot (that is, a surrounding wireless communication device does not use it). This is a method for transmitting and receiving a radio signal in a slot selected from among (slots). The PCA method is a method for transmitting and receiving a radio signal from a radio communication device having a high priority in a slot that is not used in the vicinity.

  As described above, conventionally, the DRP reservation method and the PCA method are used to prevent the transmission of a plurality of wireless signals in the same time zone, thereby suppressing the case where interference occurs and trying to realize normal wireless communication. .

JP 2007-243749 A

  However, according to the conventional DRP reservation method and PCA method, as described above, transmission of a plurality of radio signals in the same time zone is prevented, so that there is a problem that throughput is limited.

  Therefore, the present invention has been made in view of the above problems, and an object of the present invention is to provide a novel technique capable of improving throughput by realizing transmission of radio signals in the same time zone. Another object of the present invention is to provide an improved wireless communication apparatus, wireless communication method, program, and wireless communication system.

  In order to solve the above-described problem, according to an aspect of the present invention, a wireless communication apparatus that periodically repeats a predetermined frequency hopping pattern and transmits a wireless signal in a predetermined transmission time zone, the wireless communication apparatus for surrounding wireless communication A reception unit that receives a radio signal transmitted from the device using the frequency hopping pattern; and the frequency hopping pattern of a radio signal transmitted from the surrounding wireless communication device from the radio signal received by the reception unit A detection unit that detects a start timing of the radio signal, and a setting unit that sets a start timing of the frequency hopping pattern of the radio signal transmitted in the transmission time period to a timing having a difference from the start timing detected by the detection unit; Are provided.

  In such a configuration, the wireless communication device transmits a wireless signal using a timing having a difference from the start timing of the wireless signal transmitted from the surrounding wireless communication device as the start timing of the frequency hopping pattern. Therefore, the case where the frequency band of the radio signal transmitted by the radio communication device and the radio signal transmitted from the surrounding radio communication device overlaps in the same time zone can be suppressed. As a result, even when the wireless communication device and the surrounding wireless communication devices transmit wireless signals in the same time zone, the case where both wireless signals interfere with each other is suppressed. That is, the wireless communication device can improve throughput by transmitting wireless signals in the same time zone as the surrounding wireless communication devices while maintaining normal wireless communication.

In addition, the wireless communication device includes a reservation information acquisition unit that acquires reservation information of a transmission time zone of a radio signal by the surrounding wireless communication device, and a transmission time zone of the surrounding wireless communication device is a transmission of the wireless communication device. In the case of overlapping with the time zone, the wireless communication device may further include a reception control unit that causes the reception unit to perform the reception process of the radio signal in a period before the transmission time zone.
In such a configuration, based on the control by the reception control unit, the reception unit receives the radio signal transmitted from the surrounding radio communication device during the first half of the transmission time period in which the radio signal is transmitted by the radio communication device. Therefore, the detection unit detects the accurate start timing of the frequency hopping pattern from the radio signal transmitted from the surrounding radio communication device immediately before the transmission time zone by the radio signal transmitted from the surrounding radio communication device in the transmission time zone. Can be detected.

  Each wireless communication device configuring the same wireless network as the wireless communication device shares a beacon period that arrives at a predetermined period and transmits and receives a beacon during the beacon period, and the reception control unit includes the receiving unit during the beacon period. When the beacon transmitted from the wireless communication device of another wireless network is received by the receiving unit during the beacon period, the setting unit transmits a beacon transmitted from the own device during the beacon period. The start timing of the frequency hopping pattern may be changed. In such a configuration, the wireless communication apparatus can suppress interference of both wireless signals and change the coexistence of both wireless networks without changing the beacon period.

  The reception control unit, when a radio signal transmitted from a wireless communication device of another wireless network is received by the reception unit during the beacon period, causes the reception unit to perform reception processing while avoiding the transmission time period. May be.

  The wireless communication apparatus may further include a beacon period adjustment unit that advances an arrival timing of the beacon period in the same wireless network when a beacon of another wireless network is received by the reception unit during the beacon period. Good. Specifically, the beacon period adjustment unit is configured to perform wireless communication that configures the same wireless network before the transmission start timing based on a beacon transmission start timing of the other wireless network received by the reception unit. The arrival timing of the beacon period may be advanced so that beacon transmission from the apparatus is started.

  Here, when a beacon is transmitted from a plurality of wireless communication devices at the same time, the receiving unit may perform reception processing of the beacon that has reached the receiving unit early. Therefore, as described above, the beacon period adjustment unit arrives at the beacon period so that the beacon transmission from the wireless communication devices configuring the same wireless network is started before the beacon transmission start timing of another wireless network. By advancing the timing, it is possible to normally transmit and receive beacons to and from wireless communication devices constituting the same wireless network.

  In order to solve the above-described problem, according to another aspect of the present invention, wireless communication executed in a wireless communication device that periodically repeats a predetermined frequency hopping pattern and transmits a wireless signal in a predetermined transmission time zone. A communication method comprising: a reception step of receiving a radio signal transmitted from a surrounding wireless communication device using the frequency hopping pattern; and a wireless signal received in the reception step, from the surrounding wireless communication device A detection step of detecting a start timing of the frequency hopping pattern of the radio signal to be transmitted; and a start timing of the frequency hopping pattern of the radio signal transmitted in the transmission time zone, the start timing detected in the detection step A wireless communication method comprising: setting to a timing having a difference It is.

  In such a configuration, the wireless communication device transmits a wireless signal using a timing having a difference from the start timing of the wireless signal transmitted from the surrounding wireless communication device as the start timing of the frequency hopping pattern. Therefore, the case where the frequency band of the radio signal transmitted by the radio communication device and the radio signal transmitted from the surrounding radio communication device overlaps in the same time zone can be suppressed. As a result, even when the wireless communication device and the surrounding wireless communication devices transmit wireless signals in the same time zone, the case where both wireless signals interfere with each other is suppressed. That is, since the wireless communication device transmits a wireless signal transmitted by a surrounding wireless communication device and a wireless signal in which the degree of interference is suppressed, normal wireless communication can be realized while improving throughput. .

  In order to solve the above problem, according to another aspect of the present invention, there is provided a wireless communication apparatus that transmits a wireless signal in a predetermined transmission time period by periodically repeating a predetermined frequency hopping pattern. And detecting the start timing of the frequency hopping pattern of the radio signal transmitted from the surrounding radio communication device from the radio signal transmitted using the frequency hopping pattern received from the surrounding radio communication device. And a setting unit that sets a start timing of the frequency hopping pattern of the radio signal transmitted in the transmission time zone to a timing having a difference from the start timing detected by the detection unit. A program for functioning is provided.

  Such a program can cause the hardware resources of a computer including, for example, a CPU, a ROM, or a RAM to execute the functions of the detection unit and the setting unit as described above. That is, a computer using the program can function as the above-described wireless communication device.

  In order to solve the above problem, according to another aspect of the present invention, wireless communication including a plurality of wireless communication devices that periodically repeat a predetermined frequency hopping pattern and transmit a wireless signal in a predetermined transmission time zone Each of the wireless communication devices is a receiving unit that receives a wireless signal transmitted from the surrounding wireless communication device using the frequency hopping pattern, and a wireless signal received by the receiving unit, A detection unit that detects a start timing of the frequency hopping pattern of a radio signal transmitted from the surrounding wireless communication device; and a detection unit that detects a start timing of the frequency hopping pattern of a radio signal transmitted in the transmission time period. And a setting unit configured to set to a timing having a difference from the start timing detected by the wireless communication system That.

  In such a configuration, each wireless communication device transmits a wireless signal using a timing having a difference from the start timing of the wireless signal transmitted from the surrounding wireless communication device as the start timing of the frequency hopping pattern. Therefore, the case where the frequency band of the radio signal transmitted by each radio communication device and the radio signal transmitted from the surrounding radio communication device overlaps in the same time zone can be suppressed. As a result, even if each wireless communication device and surrounding wireless communication devices transmit wireless signals in the same time zone, the case where both wireless signals interfere with each other is suppressed.

  As described above, according to the wireless communication device, the wireless communication method, the program, and the wireless communication system according to the present invention, the throughput can be improved by realizing the transmission of the wireless signal in the same time zone.

  Exemplary embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In addition, in this specification and drawing, about the component which has the substantially same function structure, duplication description is abbreviate | omitted by attaching | subjecting the same code | symbol.

Further, the “best mode for carrying out the invention” will be described according to the following item order.
[1] Overview of wireless communication system according to the present embodiment [1-1] Configuration example of wireless communication system [1-2] About time division control [1-3] About beacon [1-4] About TFC code [2] ] Background to the present embodiment [3] Detailed description of the present embodiment [3-1] Configuration of the wireless communication apparatus according to the present embodiment [3-2] First operation of the wireless communication system according to the present embodiment Example [3-3] Second operation example of the wireless communication system according to the present embodiment [3-4] Third operation example of the wireless communication system according to the present embodiment [3-5] Wireless operation according to the present embodiment Example of communication device operation [4] Summary

[1] Overview of Radio Communication System According to this Embodiment [1-1] Configuration Example of Radio Communication System First, a configuration example of the radio communication system 1 according to this embodiment will be described with reference to FIG.

  FIG. 1 is an explanatory diagram showing a configuration example of a wireless communication system 1 according to the present embodiment. The circles in FIG. 1 indicate the wireless communication devices 10A to 10G that perform wireless communication using the same TFC code, and the area indicated by the dotted line indicates the radio wave reachable range in which the wireless communication devices 10A to 10G can perform communication. 12A-12G are shown.

  Specifically, the wireless communication device 10A can communicate with the wireless communication device 10B included in the radio wave reachable range 12A. The wireless communication device 10B can communicate between the wireless communication device 10A and the wireless communication device 10C included in the radio wave reachable range 12B. Similarly, the wireless communication device 10C can communicate with the wireless communication device 10B, the wireless communication device 10D, the wireless communication device 10F, and the wireless communication device 10G. Further, the wireless communication device 10D can communicate with the wireless communication device 10C, the wireless communication device 10E, and the wireless communication device 10F. The wireless communication device 10E can communicate with the wireless communication device 10D.

  The wireless communication device 10F can communicate with the wireless communication device 10C, the wireless communication device 10D, and the wireless communication device 10G included in the radio wave reachable range 12F. Similarly, the wireless communication device 10G can communicate with the wireless communication device 10C and the wireless communication device 10F.

  Each of such wireless communication devices 10A to 10G transmits and receives beacons as an example of communication management information at a predetermined period to form an autonomously distributed wireless network (ad hoc network). Details of the beacon will be described later with reference to FIGS. 3 and 4. And each radio | wireless communication apparatus 10A-10G which comprises a radio | wireless network can transmit / receive various data. Various types of data include music data such as music, lectures, and radio programs, video data such as movies, television programs, video programs, photos, documents, pictures and charts, and arbitrary data such as games and software. It is done.

  In the following description, the radio communication devices 10A to 10G are simply indicated as the radio wave reachable range 12 when it is not necessary to distinguish between the radio communication devices 10A to 10G, and the radio wave reachable ranges 12A to 12G are simply indicated as the radio wave reachable range 12. Further, FIG. 1 shows the wireless communication system 1, and simultaneously shows a wireless network. Therefore, it can be considered that the wireless communication system 1 and the wireless network can be used almost synonymously. However, since the term “network” generally refers to a structure including a link in addition to a node (wireless communication apparatus), the wireless network is considered to be different from the wireless communication system 1 in that it includes a link in addition to the wireless communication apparatuses 10A to 10G. You can also

  The wireless communication device 10 includes a PC (Personal Computer), a home video processing device (DVD recorder, VCR, etc.), a mobile phone, a PHS (Personal Handyphone System), a portable music playback device, a portable video processing device, It may be an information processing apparatus such as a PDA (Personal Digital Assistant), a home game machine, a portable game machine, or a home appliance.

[1-2] Time-sharing control The configuration example of the autonomous distributed wireless communication system 1 has been described above. Next, a superframe for time division control in the wireless communication system 1 will be described with reference to FIG.

  FIG. 2 is an explanatory diagram showing a configuration example of a superframe. The super frame period is defined by a predetermined time (for example, 65 ms), and is subdivided into 256 media access slots (MAS). The wireless communication devices 10 constituting one wireless network share the super frame period as a frame of a predetermined period, and transfer of messages is performed in units of the subdivided MAS.

  Furthermore, at the head of the super frame, there is a beacon period (BP) as a management area for transmitting and receiving management information by a beacon (beacon signal), and a beacon slot (BS) is arranged at a predetermined interval. Yes. In addition, a unique beacon slot is set for each wireless communication device 10, and parameters for network management and access control are exchanged with surrounding wireless communication devices 10. FIG. 2 shows an example in which nine beacon slots BS0 to BS8 are set as the beacon period. The period that is not set as the beacon period is normally used as a data transmission area.

[1-3] Beacon FIG. 3 shows the beacon slot position of the own device set by each wireless communication device 10 when the wireless communication devices 10A to 10G form one wireless communication system. It is a conceptual diagram. Here, each wireless communication device 10 constituting one wireless communication system 1 notifies a beacon slot that is not used in the beacon period, thereby selecting a beacon slot used by the device itself. .

  In the example illustrated in FIG. 3, the wireless communication device 10A transmits its own beacon at BS3, and the wireless communication device 10B transmits its own beacon at BS5. Similarly, the wireless communication device 10C transmits its beacon at BS2, and the wireless communication device 10D transmits its beacon at BS3. The wireless communication device 10E transmits its beacon at BS5. The wireless communication device 10F transmits its beacon at BS4, and the wireless communication device 10G transmits its beacon at BS6.

  In the example illustrated in FIG. 3, the wireless communication device 10A and the wireless communication device 10D use a common BS3, and the wireless communication device 10B and the wireless communication device 10E use a common BS5. However, since the wireless communication device 10A and the wireless communication device 10D are separated by 3 hops or more, and the wireless communication device 10B and the wireless communication device 10E are separated by 3 hops or more, a plurality of wireless communication devices use a common BS. However, there will be no practical hindrance.

  In addition, BS0, BS1, BS7, and BS8 are secured as necessary for a wireless communication apparatus that newly enters the wireless communication system 1. Usually, a predetermined number of empty beacon slots are provided behind the beacon slot of the own device. These empty beacon slots are prepared for new entry of new wireless communication devices.

  In the state illustrated in FIG. 1, when the power of the wireless communication device 10 </ b> C (shown in black in FIG. 1) is turned off and the wireless communication device 10 </ b> C no longer exists in the wireless communication system 1, the wireless communication system 1 has a plurality of wireless communication devices. Split into a network (wireless communication system). That is, the wireless communication devices 10A and 10B (indicated by colored circles in FIG. 1) form a first wireless network, and the wireless communication devices 10D to 10G (indicated by colorless circles in FIG. 1) are second. Form a wireless network.

  Further, the wireless communication devices 10A, 10B, and 10D to 10G change the BS to be used as necessary. For example, as illustrated in FIG. 3, the wireless communication device 10B uses the front BS2, and the wireless communication device 10G uses the front BS. If the power of the wireless communication device 10C is turned on with the BS changed in this way, the wireless communication device 10C uses the same BS2 by the plurality of wireless communication devices 10B and 10G, so that the wireless network It is difficult to accurately grasp the current state of

  FIG. 4 is an explanatory diagram showing a configuration example of a beacon frame. As shown in FIG. 4, the beacon frame includes a preamble 60, a PHY header 62, a MAC header 70, an HCS 71, a payload 72, and an FCS 73.

  The preamble 60 is attached to acquire synchronization when the wireless communication apparatus 10 receives a wireless signal such as a beacon, and has a unique fixed pattern for each TFC code. The PHY header 62 describes information related to the physical layer of the beacon, and includes information indicating the TFC code of the beacon, for example.

  The MAC header 70 includes frame control information 701 indicating the format of the frame, a destination address 702 of the frame, a source address 703 of the frame, sequence control information 704 such as a sequence number of the frame, an access method, and the like. The access control information 705 shown is included.

  An HCS (Header Check Sequence) 71 is added to determine whether or not there is an error in the header information described up to the MAC header 70.

  The payload 72 includes a beacon parameter 721, a beacon slot use information element 722, an arbitrary information element (part 1) 723, and an arbitrary information element (part N) 724. Further, the beacon parameter 721 includes a device identifier 771, a beacon slot number 772, and device control information 773. The beacon frame may include a DRP reservation information element (DRPIE) for realizing the DRP reservation method as an information element.

  Each wireless communication device 10 can form an autonomously distributed wireless network by transmitting and receiving beacons having such a frame configuration during the beacon period.

[1-4] TFC Code Next, a TFC (Time Frequency Code) code will be described with reference to FIGS. 5 and 6.

FIG. 5 is an explanatory diagram showing the configuration of the frequency channel of the multiband OFDM system. As shown in FIG. 5, Wimedia Alliance Multi
The Band OFDM PHY specification defines that a total of 14 subbands having a bandwidth of 528 KHz are arranged between 3.1 GHz and 10.6 GHz.

  In addition, the subbands are divided into three in order from the lowest frequency, and band group 1, band group 2, band group 3, and band group 4 are configured, and band group 5 is configured by the remaining two subbands. The

  A plurality of TFC codes 1 to 7 shown in FIG. 5 are configured by changing the frequency hopping pattern for each band group.

  FIG. 6 is an explanatory diagram showing an example of a frequency hopping pattern of the TFC code. 6A shows a frequency hopping pattern of TFC code 1, FIG. 6B shows a frequency hopping pattern of TFC code 2, FIG. 6C shows a frequency hopping pattern of TFC code 3, and FIG. 6D shows TFC code 4 6E shows the frequency hopping pattern of the TFC code 5, FIG. 6F shows the frequency hopping pattern of the TFC code 6, and FIG. 6G shows the frequency hopping pattern of the TFC code 7.

  The frequency hopping pattern is defined by a channel code called TFC. For example, when the channel is TFC code 1, as shown in FIG. 6A, the subbands used according to the rules of subband 1, subband 2, subband 3, subband 1, subband 2, and subband 3 are used. The band changes. Of the sub-bands constituting a certain band group, the sub-band having the lowest frequency band is sub-band 1, the sub-band having the highest frequency is sub-band 3, and is intermediate between sub-band 1 and sub-band 3. The subband may be subband 2.

  As shown in FIG. 6B, when the channel is TFC code 2, it is used according to the rules of subband 1, subband 3, subband 2, subband 1, subband 3, and subband 2. Subband changes.

  Also, as shown in FIG. 6C, when the channel is TFC code 3, it is used in accordance with the rules of subband 1, subband 1, subband 2, subband 2, subband 3, and subband 3. Subband changes. Similarly, as shown in FIG. 6D, when the channel is TFC code 4, it is used according to the rules of subband 1, subband 1, subband 3, subband 3, subband 2, and subband 2. Subbands to be changed.

  Further, in the multiband OFDM system, patterns for performing frequency hopping between two subbands, such as TFC codes 5 to 7, are also prepared.

  Specifically, as shown in FIG. 6E, the TFC code 5 uses only subband 1 and subband 2 alternately. Further, as shown in FIG. 6F, the TFC code 6 uses only subband 1 and subband 3 alternately. Similarly, as shown in FIG. 6G, the TFC code 7 uses only subbands 2 and 3 alternately. Thus, the frequency hopping pattern to be used is determined according to the TFC code to be set.

  In addition, a predetermined preamble sequence corresponding to each TFC code is prepared for the TFC code to be used. The preamble is a synchronization signal added to a signal to be transmitted / received. Each data indicated by a square frame in FIG. 6 group may be one OFDM symbol, or may be data transmitted in a time of 312.5 ns.

[2] Background to the Present Embodiment The outline of the present embodiment has been described above with reference to FIGS. Subsequently, the background to the present embodiment will be described with reference to FIG.

  The conventional simple time division multiplexing method using the carrier detection multiple access / collision avoidance method (CSMA / CA method) has a problem that different communication cannot be performed in the same space at the same time. That is, there is a problem that throughput is reduced because wireless communication devices existing around the wireless communication device that is transmitting cannot use the transmission path.

  Furthermore, in the ultra wide band wireless communication system, since communication is performed using extremely weak radio waves, there is a problem that access control using the conventional carrier detection multiple access / collision avoidance method (CSMA / CA method) cannot be performed. there were. In transmission control by PCA similar to the carrier detection multiple access / collision avoidance method (CSMA / CA method), the wireless communication device transmits a wireless signal when it does not detect a wireless signal from a surrounding wireless communication device. Yes. However, if a false detection occurs when there is essentially no signal, there is a problem that the wireless communication device loses a transmission opportunity.

  In addition, in the method using simply time division multiplexing, while the time is occupied by a specific wireless communication device, other wireless communication devices cannot communicate, so the number of wireless communication devices that use all the bandwidth There was a problem that the throughput was obtained only in the bandwidth of the time divided by the number corresponding to the minutes.

  As another conventional problem, in the case of a radio communication system based on the multiband OFDM method, if radio signals from a plurality of radio communication apparatuses are received almost simultaneously, a desired signal cannot be decoded. This is because, as shown in FIG. 7, even if the wireless communication device uses a different TFC code, the wireless communication device receives it in synchronization with the wireless signal with the earlier reception timing.

  FIG. 7 is an explanatory diagram showing the relationship between radio signal collisions and decoding results. More specifically, in FIG. 7, the wireless communication device 11C is present at a position where it can receive the wireless signals transmitted from the wireless communication devices 11B and 11D, and the reception processing is performed in the MAS set in advance. Shows the case.

  As shown in FIG. 7, when wireless signals are transmitted from the wireless communication devices 11B and 11D almost simultaneously, the wireless communication device 11C starts decoding the preamble 60 added to the wireless signal. When the wireless communication device 11C has a general reception function, synchronization is obtained using the correlator of the preamble 60, and information bits such as the PHY header 62 and the MAC header 70 thereafter are used using a predetermined Viterbi decoding device or the like. Thus, a process of decoding into a plausible signal is performed.

  Therefore, when wireless signals are transmitted almost simultaneously from wireless communication devices 11B and 11D, wireless communication device 11C is assumed to decode only the wireless signal that first detected preamble 60 with high probability. In FIG. 7, the signal transmission from the wireless communication device 11B is earlier than the signal transmission from the wireless communication device 11D, and only the wireless signal transmitted from the wireless communication device 11B is decoded.

  For this reason, even when performing DRP reservation and performing wireless communication, if the same slot is reserved, the wireless communication apparatus originally receives the interference partner's wireless signal at subtle timing. The problem that the signal which should be received cannot be received arises. This problem also occurs when a plurality of wireless networks having overlapping beacon periods are close to each other.

  Note that the proximity of a plurality of wireless networks with overlapping beacon periods is, for example, as described with reference to FIG. 3, because one wireless network does not exist in the wireless network and one wireless network becomes two wireless networks. Occurs when the wireless communication device attempts to join a wireless network.

  Accordingly, the wireless communication device 10 according to the present embodiment has been created with the above circumstances taken into consideration. According to the wireless communication apparatus 10 according to the present embodiment, it is possible to improve throughput by realizing transmission of wireless signals in the same time zone. In addition, the wireless communication device 10 can improve the success rate of beacon transmission and reception when wireless networks with overlapping beacon periods are close to each other. Hereinafter, such a wireless communication device 10 will be described in detail.

[3] Detailed Description of the Present Embodiment [3-1] Configuration of Radio Communication Device According to the Present Embodiment FIG. 8 is a functional block diagram showing the configuration of the radio communication device 10 according to the present embodiment. As shown in FIG. 8, the wireless communication device 10 includes an antenna 101, a high frequency reception processing unit 102, a reception signal decoding processing unit 103, a reception data buffer 104, a beacon processing unit 105, a transmission / reception control unit 106, TFC synchronization detection unit 107, TFC offset interval setting unit 108, BPST (Beacon Period Start Time) synchronization setting unit 109, TFC setting unit 110, interface 111, transmission data buffer 112, DRP reservation analysis unit 113, , A DRP reservation management unit 114, a beacon generation unit 115, a transmission signal code processing unit 116, and a high frequency transmission processing unit 117.

  The antenna 101 is an interface with surrounding wireless communication devices, functions as a reception unit that receives a radio signal in cooperation with the high frequency reception processing unit 102, and wirelessly operates in cooperation with the high frequency transmission processing unit 117. It functions as a transmission unit that transmits signals.

  The radio frequency reception processing unit 102 performs radio signal reception processing in synchronization with the preamble added to the radio signal (high frequency ultra-wide band signal) received by the antenna 101. For example, the high frequency reception processing unit 102 down-converts the baseband signal received by the antenna 101 and converts it into a bit string.

  The reception signal decoding processing unit 103 extracts specific data from the bit string obtained by the high frequency reception processing unit 102, and the reception data buffer 104 holds the data extracted by the reception signal decoding processing unit 103.

  The beacon processing unit 105 analyzes the beacon frame and outputs DRP reservation information to the DRP reservation analysis unit 113. The DRP reservation analysis unit 113 identifies empty slots by analyzing the DRP reservation information. When there is transmission data, the DRP reservation management unit 114 reserves one of the empty slots specified by the DRP reservation analysis unit 113.

  The transmission / reception control unit 106 causes the high frequency reception processing unit 102 to perform reception processing or causes the high frequency transmission processing unit 117 to perform transmission processing in the slot for which the reservation is set by the DRP reservation management unit 114. That is, the transmission / reception control unit 106 includes a function as a transmission control unit and a function as a reception control unit. The transmission / reception control unit 106 may cause the high-frequency reception processing unit 102 to perform reception processing in addition to the slot for which the reservation is set by the DRP reservation management unit 114. For details, see FIG. 10 and FIG. Will be described later.

  For example, the TFC setting unit 110 sets a TFC code used by the wireless communication apparatus 10 when transmitting and receiving a wireless signal in any of the TFC codes 1 to 7 shown in FIG. The interface 111 transfers the reception data held in the reception data buffer 104 to the application device, and receives transmission data to be held in the transmission data buffer 112 from the application device. The transmission data buffer 112 holds transmission data obtained from the application device via the interface 111.

  For example, as illustrated in FIG. 4, the beacon generation unit 115 generates a beacon frame including information elements describing the status of surrounding wireless communication devices and the setting status of slot reservation of the own device. The transmission signal code processing unit 116 encodes information bits of data obtained from the beacon generation unit 115 or the transmission data buffer 112 into a transmission signal by signal processing. The high-frequency transmission processing unit 117 modulates the transmission signal encoded by the transmission signal code processing unit 116 into a high-frequency ultra-wideband signal, and transmits it from the antenna 101 as a radio signal.

  The TFC synchronization detection unit 107 has a function as a detection unit that detects the start timing of the TFC code of the wireless signal transmitted from the surrounding wireless communication device based on the synchronization of the preamble acquired by the high frequency reception processing unit 102. . Here, the start timing of the TFC code means the start timing of each subband that appears every time one period of frequency hopping is performed. For example, when the wireless communication device 10 receives a wireless signal transmitted with the TFC code 1 illustrated in FIG. 6A, the TFC synchronization detection unit 107 detects the reception start timing of the data transmitted with the subband 1. Good.

  As shown in FIG. 9, the TFC offset interval setting unit 108 sets the start timing of the TFC code of the radio signal transmitted from the radio communication device 10 to the timing having the timing detected by the TFC synchronization detecting unit 107 and the offset. Function as a setting unit. For example, the TFC offset interval setting unit 108 sets the TFC code start timing by setting the offset interval with the timing detected by the TFC synchronization detection unit 107.

  FIG. 9 is an explanatory diagram showing a state of frequency hopping of a plurality of radio signals. More specifically, FIG. 9 shows that when the first wireless network (NW1) is transmitting a wireless signal with the TFC code 1, the wireless communication device 10 belonging to the second wireless network (NW2) transmits the wireless signal. The state of transmission is shown.

  When the radio signal of the first radio network as shown in FIG. 9 is received, the TFC synchronization detection unit 107 determines the timing at which subband 1 appears as the start timing of the TFC code of the radio signal of the first radio network. Detect as. Then, the TFC offset interval setting unit 108 sets the TFC code start timing and the offset interval of the timing detected by the TFC synchronization detection unit 107, for example, so as not to overlap with the frequency band used by the radio signal of the first radio network. Set to time for ~ 2 OFDM symbols.

  As a result, as illustrated in FIG. 9, the wireless communication device 10 can transmit the wireless signal while avoiding the frequency band (subband) of the wireless signal of the first wireless network at the same time point. Note that the offset interval set by the TFC offset interval setting unit 108 may be determined in advance for each TFC code.

  The BPST synchronization setting unit 109 is a beacon period adjustment unit that advances the arrival timing of the beacon period when a beacon transmitted from the first wireless network is received during the beacon period of the second wireless network to which the wireless communication device 10 belongs. It has the function of.

  The BPST synchronization setting unit 109 has a configuration provided to solve the problem described with reference to FIG. The fact that the beacon transmitted from the first wireless network is received during the beacon period of the second wireless network to which the wireless communication device 10 belongs is, as shown in FIG. 7, the beacon of the first wireless network. May have been transmitted earlier than a beacon with a second wireless network. Therefore, the BPST synchronization setting unit 109 may transmit a beacon having the second wireless network earlier than a beacon of the first wireless network by advancing the arrival timing of the second beacon period. As a result, the wireless communication device 10 can normally receive a beacon having the second wireless network.

  When the wireless communication device 10 uses the earliest BS in the second wireless network, the wireless communication device 10 advances the beacon transmission timing by, for example, 1 to 2 OFDM symbols, thereby causing the beacon period arrival timing. Can be expedited. Further, in order to advance the arrival timing of the beacon period, the period of a certain super frame may be temporarily shortened. Further, advancing the arrival timing of the beacon period is equivalent to advancing the switching timing of the superframe. Therefore, the wireless communication device 10 may advance the arrival timing of the beacon period of the second wireless network by transmitting a beacon including information for transition of the superframe period to the surroundings.

[3-2] First Operation Example of Radio Communication System According to this Embodiment Next, a first operation example of the radio communication system according to this embodiment will be described with reference to FIG.

  FIG. 10 is a sequence diagram showing a first operation example of the wireless communication system according to the present embodiment. Specifically, FIG. 10 shows an operation example when the radio communication apparatus 10C reserves transmission of a radio signal in a slot by DRP reservation. In this case, the transmission / reception control unit 106 of the wireless communication device 10C causes the high-frequency reception processing unit 102 to perform reception processing in a period before the slot reserved for transmission of the wireless signal.

  Therefore, as shown in FIG. 10, when a radio signal is transmitted from the radio communication device 10B belonging to the first network using the TFC code 1, the radio communication device 10C belonging to the second network is transmitted from the radio communication device 10B. The detected radio signal is detected (S210). That is, the TFC synchronization detection unit 107 detects the start timing of the TFC code of the radio signal transmitted from the radio communication device 10B.

  Thereafter, the TFC offset interval setting unit 108 of the wireless communication apparatus 10C sets the offset interval between the start timing of the TFC code and the timing detected by the TFC synchronization detection unit 107, for example, to a time corresponding to 1-2 OFDM symbols (S220). . As a result, the radio communication device 10C can transmit a radio signal with a timing different from the start timing of the TFC code of the radio signal transmitted from the radio communication device 10B (S230).

  Note that when the TFC code is the TFC code 3 shown in FIG. 6C or the TFC code 4 shown in FIG. 6D, the offset interval set by the TFC offset interval setting unit 108 is 2-4 OFDM as shown in FIG. It may be a symbol.

  FIG. 11 is another explanatory diagram showing a state of frequency hopping of a plurality of radio signals. As shown in FIG. 11, when the first radio network and the second radio network use the TFC code 3, the TFC offset interval setting unit 108 may set an offset interval of 2 to 4 OFDM symbols. With this configuration, as shown in FIG. 11, the radio signal of the first radio network and the radio signal of the second radio network can coexist in the same time zone.

[3-3] Second Operation Example of Radio Communication System According to the Present Embodiment Next, a second operation example of the radio communication system according to the present embodiment will be described with reference to FIG. In the first operation example, the TFC offset interval setting unit 108 of the wireless communication device 10C sets the offset interval of the TFC code of the wireless signal transmitted from the wireless communication device 10B when transmitting the wireless signal from the wireless communication device 10C. did. On the other hand, the second operation example is different from the first operation example in that the offset interval of the TFC code of the radio signal transmitted from the radio communication device 10B is set in advance.

  FIG. 12 is a sequence diagram showing the flow of the second operation example of the wireless communication system according to the present embodiment. First, the wireless communication device 10C belonging to the second network receives a beacon from the wireless communication device 10D during the beacon period (S240), and transmits a beacon to the surroundings (S244). Subsequently, when the wireless signal transmitted from the first wireless network is received during the beacon period (S248), the transmission / reception control unit 106 of the wireless communication apparatus 10C receives a high frequency during a period other than the slot reserved by the own apparatus. The reception processing unit 102 is caused to perform reception processing (scanning) (S252).

  Then, while the high-frequency reception processing unit 102 performs scanning based on the control by the transmission / reception control unit 106 (S256), the beacon period of the first wireless network arrives, and the beacon is transmitted / received in the first wireless network. (S260, S264). The TFC synchronization detection unit 107 detects the start timing of the TFC code of the beacon from the beacon received by the high frequency reception processing unit 102 of the wireless communication device 10C, and the TFC offset interval setting unit 108 determines the offset interval based on the start timing. Setting is made (S268). Thereafter, the wireless communication device 10C transmits a wireless signal according to the offset interval set in S268 (S272).

[3-4] Third Operation Example of Radio Communication System According to this Embodiment Next, a third operation example of the radio communication system according to this embodiment will be described with reference to FIG.

  FIG. 13 is an explanatory diagram showing a third operation example of the wireless communication system according to the present embodiment. As shown in FIG. 13, after the wireless communication device 10C belonging to the second wireless network transmits a beacon in the beacon period of the second wireless network (S302), the wireless communication device 10D transmits the beacon (S304). .

  Further, it is assumed that the beacon transmitted from the wireless communication device 10B belonging to the first wireless network arrives at the wireless communication device 10C earlier than S304 due to the overlap of the beacon periods of the second wireless network and the first wireless network ( S306). In this case, the high-frequency reception processing unit 102 of the wireless communication device 10C receives a beacon transmitted from the wireless communication device 10B instead of a beacon transmitted from the wireless communication device 10D, thereby detecting overlapping beacon periods. Is done. Thereafter, the wireless communication device 10A transmits a beacon (S308).

  The BPST synchronization setting unit 109 of the wireless communication device 10C adjusts the superframe period and advances the arrival timing of the beacon period when the overlap of beacon periods and beacon slot contention are detected (S310). Specifically, the BPST synchronization setting unit 109 may decrease the period of one superframe by, for example, an offset interval of 1 to 2 OFDM symbols.

  Then, the wireless communication device 10C and the wireless communication device 10D transmit beacons in their own beacon slots in the beacon period whose arrival timing is advanced (S312 and S314). As a result, since the beacon is transmitted from the wireless communication device 10B after the wireless communication device 10D (S316), the wireless communication device 10C can normally receive the beacon transmitted from the wireless communication device 10D. Become.

  In FIG. 13, the case where the wireless communication device 10 </ b> C detects a beacon collision in a beacon slot behind the beacon slot of the own device is illustrated, but a case where a beacon collision is detected in front of the beacon slot of the own device. Is also envisaged. In this case, the wireless communication device 10 </ b> C may adjust the next beacon period by adjusting the transmission timing of the beacon slot of the device itself in the superframe in which the beacon collision is detected.

  FIG. 13 shows an example in which the beacon period of the next superframe arrives earlier for convenience. Actually, the own apparatus finely adjusts the timing to advance the beacon transmission timing. The beacon of the wireless communication device 10D that should be received is received.

[3-5] Example of Operation of Wireless Communication Device According to Present Embodiment Next, a wireless communication method executed in the wireless communication device 10 according to the present embodiment will be described with reference to FIGS. 14 and 15.

  14 and 15 are flowcharts showing the flow of the wireless communication method executed in the wireless communication apparatus 10 according to the present embodiment. In the description of FIGS. 14 and 15, it is assumed that a specific TFC code is already set in the wireless communication device 10 and a wireless network is formed with surrounding wireless communication devices.

  As shown in FIG. 14, the wireless communication device 10 according to the present embodiment is a beacon period (S401) in the superframe period (S401), and corresponds to the beacon transmission slot of the own device (S402). If an offset interval is set (S403), a beacon is transmitted (S405) so that the start timing of the TFC code comes at a timing according to the set offset interval (S404). Note that the wireless communication device 10 transmits a beacon at the start timing of a normal TFC code unless an offset interval is set.

  On the other hand, if it is not the beacon transmission slot of the own device during the beacon period, the transmission / reception control unit 106 causes the high frequency reception processing unit 102 to perform reception processing (S406), and when a beacon is received (S407), the beacon processing unit 105 Collects the beacon information described in the beacon (S408).

  Here, if the received beacon is a beacon transmitted from a new (another) wireless communication device in a beacon slot that has already been used around its own device (S409), the BPST synchronization setting unit 109 Once fine adjustment is made to set the superframe interval slightly short (S410).

  Further, the DRP reservation analysis unit 113 analyzes the DRP reservation information included in the beacon, and if a reservation request addressed to the own device is included (S411), the beacon generation unit 115 adds the DRP reservation information for reservation response to the beacon. (S412), and setting for reception in the slot (MAS) reserved by the transmission / reception control unit 106 (S413).

  On the other hand, if the DRP reservation information includes a reservation response addressed to the own device (S414), the transmission / reception control unit 106 sets transmission in the reserved slot (MAS) (S415). If the DRP reservation information addressed to the other device has a setting in which the reservation conflicts with the slot (MAS) in which the reservation of the own device is set (S416), the transmission / reception control unit 106 sets other information before the transmission slot of the own device. In order to avoid competition with communication, reception is set (S417).

  If the received frame is not a beacon from an unregistered wireless communication device (S418), the transmission / reception control unit 106 sets a scan operation during a period in which the transmission / reception control unit 106 is not operating as a transmission / reception slot of the own device in the superframe. (S419). Then, the TFC offset interval setting unit 108 sets a TFC offset interval corresponding to, for example, 1 to 2 OFDM symbols or 2 to 3 OFDM symbols (S420).

  When the wireless communication device 10 receives the transmission data via the interface 111 (S421), the DRP reservation management unit 114 acquires the beacon information of the reception destination device (S422), and determines the free slot (MAS) status and the own state. The slot (MAS) to be used is specified in consideration of the empty slot (MAS) status of the device. Subsequently, the beacon generation unit 115 adds a DRP reservation information for reserving the specified slot and constructs a beacon frame (S423).

  If a preset reception slot (MAS) has arrived (S424), the transmission / reception control unit 106 causes the high-frequency reception processing unit 102 to perform reception processing (S425). When the header information whose destination is addressed to the own apparatus is received (S426), the high frequency reception processing unit 102 further performs reception processing of the data payload portion (S427). Thereafter, the wireless communication device 10 outputs the collected data via the interface (S428).

  On the other hand, if header information whose destination is addressed to another device is received in the reception slot and the wireless signal including the header information is a beacon from an unregistered wireless communication device (S429), the DRP reservation described in the beacon If the information competes with the transmission slot of the own device (S430), the transmission / reception control unit 106 performs reception setting for avoiding competition with other communications (S431).

  Thereafter, the transmission / reception control unit 106 causes the high-frequency reception processing unit 102 to suspend the reception processing (S432), and returns to S424 again to perform reception processing of the signal addressed to the own device, thereby awaiting data that the own device should originally receive. .

  On the other hand, when the time obtained by subtracting the predetermined time from the preset transmission slot (MAS) has arrived (S433), the transmission / reception control unit 106 causes the high-frequency reception processing unit 102 to start reception processing (S434). When header information whose destination is another apparatus is received (S435), the TFC offset interval setting unit 108 sets an offset interval corresponding to, for example, 1 to 2 OFDM symbols or 2 to 3 OFDM symbols ( S436).

  If header information whose destination is the own device is received, the process may return to S427 to receive data addressed to the own device. Alternatively, since the transmission is not intended for the slot to be originally received, the data following the header information may be discarded.

  If the transmission timing has arrived (S437) and the offset interval has been set in S420 or S436 (S438), the wireless communication apparatus 10 uses the timing obtained by adding the offset interval as the start timing of the TFC code (S439). ) The data of its own device is transmitted (S440).

  Next, in order to clearly show the points of the present embodiment, the offset interval setting operation will be described mainly with reference to FIG.

  As shown in FIG. 15, the transmission / reception control unit 106 of the wireless communication apparatus 10 causes the high frequency reception processing unit 102 to start reception processing (S501). Then, when the synchronization of the preamble is started by the high-frequency reception processing unit 102 and the preamble is synchronized (S502), the reception signal decoding processing unit 103 decodes the radio signal following the preamble (S503).

  Subsequently, the transmission / reception control unit 106 refers to the source address described in the MAC header portion of the information decoded by the received signal decoding processing unit 103 (S504). The transmission / reception control unit 106 compares the source address with the managed address (S505). Here, the address managed by the transmission / reception control unit 106 may be an address of a wireless communication device recognized as a wireless communication device constituting the same wireless network. If the result of S506 is that the source address is the address of an unregistered wireless communication device (S506), the transmission / reception control unit 106 sets the transmission start timing of its own device managed by the DRP reservation management unit 114. Reference is made (S507).

  When the wireless signal transmitted from the unregistered wireless communication device collides with the transmission timing of the own device (S508), the TFC offset interval setting unit 108 sets the TFC cycle of the unregistered wireless communication device. From (Start Timing), an offset interval for delaying the start timing of the TFC code by 1 to 2 OFDM symbols or 2 to 3 OFDM symbols is set (S509).

  Further, the high-frequency transmission processing unit 117 performs a wireless signal transmission process using the timing obtained by adding the offset interval to the start timing of the TFC code of the unregistered wireless communication apparatus as the start timing of the TFC code (S510).

[4] Summary As described above, the wireless communication apparatus 10 according to the present embodiment uses a timing having a difference from the start timing of the wireless signal transmitted from the surrounding wireless communication apparatus as a start timing of the TFC code. Send. Therefore, the case where the frequency band of the radio signal transmitted from the radio communication device 10 and the radio signal transmitted from the surrounding radio communication device overlap in the same time zone can be suppressed. As a result, even when the wireless communication device 10 and surrounding wireless communication devices transmit wireless signals in the same time zone, the case where both wireless signals interfere with each other is suppressed. That is, the wireless communication device 10 can improve throughput by transmitting wireless signals in the same time zone as the surrounding wireless communication devices while maintaining normal wireless communication.

That is, even when the wireless communication device 10 is included in the radio wave reach of other wireless communication devices belonging to different wireless networks, it is only necessary to finely adjust the start timing of the TFC code while maintaining the synchronization of both wireless networks. Both wireless networks can coexist.

  Further, when the wireless communication device 10 detects a wireless signal transmitted from another wireless communication device, if there is a data transmission schedule within the superframe, the wireless communication device 10 performs a scanning operation prior to transmission of the own device. Then, when the TFC offset interval setting unit 108 sets the offset interval based on the scan result, the wireless communication device 10 competes with other wireless communication devices for transmission time zones when the transmission schedule of the own device arrives. However, it is possible to transmit radio signals while avoiding interference.

  In addition, the BPST synchronization setting unit 109 finely adjusts the superframe interval of the own device when a beacon from a new wireless communication device is detected in the existing beacon slot of the own device. Specifically, the BPST synchronization setting unit 109 may set the superframe interval of its own device to be shorter by, for example, 1 to 2 OFDM symbols. As a result, in a later superframe, a beacon can be received at a timing earlier than a beacon transmitted from a new wireless communication device.

  Further, when a beacon from a new wireless communication device is detected, the TFC offset interval setting unit 108 sets an offset interval in the beacon transmission slot of the own device. As a result, when beacon slots of a plurality of wireless communication devices including a new wireless communication device collide, interference of a plurality of beacons in surrounding wireless communication devices can be suppressed.

  In addition, when the same slot reservation as that of the own device is set in the DRP reservation information that other wireless communication devices set to use, the TFC offset interval setting unit 108 sets the offset interval in advance. And the radio | wireless communication apparatus 10 obtains the method of coexisting communication, without changing a reservation by performing communication according to this offset space | interval in a corresponding slot.

  Thus, compared to the conventional carrier detection multiple access control method in which only one communication is recognized in the same space, the present embodiment can coexist with a plurality of communications, so that throughput is reduced. It can be improved dramatically.

  In addition, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to the example which concerns. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Understood.

  For example, each step in the processing of the wireless communication device 10 of the present specification does not necessarily have to be processed in time series in the order described as a flowchart or a sequence diagram. For example, each step in the processing of the wireless communication device 10 may include processing executed in parallel or individually (for example, parallel processing or object processing).

  Further, it is possible to create a computer program for causing hardware such as a CPU, a ROM, and a RAM built in the wireless communication device 10 to perform the same functions as the components of the wireless communication device 10 described above. A storage medium storing the computer program is also provided. Also, a series of processing can be realized by hardware by configuring each functional block shown in the functional block diagram of FIG. 8 with hardware.

It is explanatory drawing which showed the structural example of the radio | wireless communications system concerning this embodiment. It is explanatory drawing which showed the structural example of the super frame. It is the conceptual diagram which showed the beacon slot position. It is explanatory drawing which showed the structural example of the beacon frame. It is explanatory drawing which showed the structure of the frequency channel of a multiband OFDM system. It is explanatory drawing which showed the frequency hopping pattern of TFC code 1. It is explanatory drawing which showed the frequency hopping pattern of TFC code 2. 6 is an explanatory diagram showing a frequency hopping pattern of TFC code 3. FIG. 4 is an explanatory diagram showing a frequency hopping pattern of a TFC code 4. FIG. 6 is an explanatory diagram showing a frequency hopping pattern of a TFC code 5. FIG. 6 is an explanatory diagram showing a frequency hopping pattern of a TFC code 6. FIG. It is explanatory drawing which showed the frequency hopping pattern of the TFC code. It is explanatory drawing which showed the relationship between the collision of a radio signal, and a decoding result. It is the functional block diagram which showed the structure of the radio | wireless communication apparatus concerning this embodiment. It is explanatory drawing which showed the mode of the frequency hopping of several radio | wireless signals. It is the sequence diagram which showed the 1st operation example of the radio | wireless communications system concerning this embodiment. It is another explanatory view showing a state of frequency hopping of a plurality of radio signals. It is the sequence diagram which showed the flow of the 2nd operation example of the radio | wireless communications system concerning this embodiment. It is explanatory drawing which showed the 3rd operation example of the radio | wireless communications system concerning this embodiment. It is the flowchart which showed the flow of the radio | wireless communication method performed in the radio | wireless communication apparatus concerning this embodiment. It is the flowchart which showed the flow of the radio | wireless communication method performed in the radio | wireless communication apparatus concerning this embodiment.

Explanation of symbols

Reference Signs List 101 antenna 102 high frequency reception processing unit 106 transmission / reception control unit 107 TFC synchronization detection unit 108 TFC offset interval setting unit 109 BPST synchronization setting unit 117 high frequency transmission processing unit

Claims (9)

A wireless communication device that periodically repeats a predetermined frequency hopping pattern to transmit a wireless signal in a predetermined transmission time zone:
A receiving unit that receives a radio signal transmitted from the surrounding radio communication device using the frequency hopping pattern;
A detection unit that detects a start timing of the frequency hopping pattern of a radio signal transmitted from the surrounding radio communication device from a radio signal received by the reception unit;
A setting unit that sets a start timing of the frequency hopping pattern of the radio signal transmitted in the transmission time period to a timing having a difference from the start timing detected by the detection unit;
A wireless communication device comprising: A reservation information acquisition unit for acquiring reservation information of a wireless signal transmission time period by the surrounding wireless communication devices;
When the transmission time zone of the surrounding wireless communication device overlaps with the transmission time zone of the wireless communication device, the wireless signal reception processing is performed in the reception unit in the period before the transmission time zone of the wireless communication device. A reception control unit for performing
The wireless communication apparatus according to claim 1, further comprising: Each wireless communication device constituting the same wireless network as the wireless communication device transmits and receives beacons during the beacon period by sharing a beacon period that arrives at a predetermined period,
The reception control unit causes the reception unit to perform reception processing during the beacon period,
When the beacon transmitted from the wireless communication device of another wireless network is received by the receiving unit during the beacon period, the setting unit determines the start timing of the frequency hopping pattern of the beacon transmitted from the own device during the beacon period. The wireless communication apparatus according to claim 2, wherein the wireless communication apparatus is changed.   The reception control unit causes the reception unit to perform reception processing while avoiding the transmission time period when a radio signal transmitted from a wireless communication device of another wireless network is received by the reception unit during the beacon period. The wireless communication apparatus according to claim 3, wherein:   The apparatus according to claim 3, further comprising a beacon period adjustment unit that accelerates arrival timing of the beacon period in the same wireless network when a beacon of another wireless network is received by the receiving unit during the beacon period. The wireless communication device described.   The beacon period adjusting unit is configured to transmit beacons from wireless communication devices constituting the same wireless network before the transmission start timing based on the beacon transmission start timing of the other wireless network received by the receiving unit. The wireless communication apparatus according to claim 5, wherein the arrival timing of the beacon period is advanced so that the communication is started. A wireless communication method executed in a wireless communication device that periodically repeats a predetermined frequency hopping pattern and transmits a wireless signal in a predetermined transmission time zone:
A receiving step of receiving a radio signal transmitted from a surrounding radio communication device using the frequency hopping pattern;
A detection step of detecting a start timing of the frequency hopping pattern of the radio signal transmitted from the surrounding radio communication device from the radio signal received in the reception step;
Setting the start timing of the frequency hopping pattern of the radio signal transmitted in the transmission time zone to a timing having a difference from the start timing detected in the detection step;
A wireless communication method comprising: Computer
A wireless communication device that periodically repeats a predetermined frequency hopping pattern to transmit a wireless signal in a predetermined transmission time zone:
A detection unit for detecting a start timing of the frequency hopping pattern of a radio signal transmitted from the surrounding radio communication device from a radio signal transmitted using the frequency hopping pattern received from the surrounding radio communication device; ;
A setting unit that sets a start timing of the frequency hopping pattern of the radio signal transmitted in the transmission time period to a timing having a difference from the start timing detected by the detection unit;
A program for causing a wireless communication apparatus to function. A wireless communication system including a plurality of wireless communication devices that periodically repeat a predetermined frequency hopping pattern and transmit a wireless signal in a predetermined transmission time zone:
Each of the wireless communication devices
A receiving unit that receives a radio signal transmitted from the surrounding radio communication device using the frequency hopping pattern;
A detection unit that detects a start timing of the frequency hopping pattern of a radio signal transmitted from the surrounding radio communication device from a radio signal received by the reception unit;
A setting unit that sets a start timing of the frequency hopping pattern of the radio signal transmitted in the transmission time period to a timing having a difference from the start timing detected by the detection unit;
A wireless communication system comprising:

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