JP2013098729A - Device, system and method for radio communication, integrated circuit and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress an influence of a radio wave for use for radio communication upon a measurement device.SOLUTION: A radio control station device includes: a receiver unit for receiving a signal from the measurement device; and a controller for performing, by setting a radio wave radiation permission period on the basis of the received signal, communication control to notify a plurality of radio communication devices of communication destinations of transmission permission to permit transmission within the radio wave radiation permission period.

Description

  The present invention relates to wireless communication technology.

  A sensor network (Wireless Sensor Networks, WSN) is a wireless network in which a plurality of wireless terminals with sensors are scattered in a space, and the environment and physical state can be collected in cooperation with each other.

  In recent years, sensor networks have been widely used and introduced into various situations (see Non-Patent Document 1 below). As the sensor network spreads, there is a problem that the communication band from the sensor node to the sink node collecting data becomes insufficient.

  In order to solve this problem, multi-user MIMO technology has been developed and introduced (see Non-Patent Document 2 below).

  In recent years, various uses are considered, and introduction into the medical-related field is also progressing (see Non-Patent Document 3 below).

Ken Sakamura: Ubiquitous Computing, Operations Research, pp. 203-209, April 2004 issue Ishihara et al., Signal Detection Method for Uplink Multi-User MIMO-OFDM Transmission -Research and Development of Spatial Axis Frequency Effective Utilization Technology-, IEICE Society Conference Proceedings 2007_Communications (1), 193, 2007-08 -29 ETSI TR 102 732 V0.4.1 (2011-03)

  However, in the medical-related field, it is necessary to measure minute bioelectricity in a measuring device such as an electrocardiogram measuring device, and if radio waves used for wireless communication are emitted in the immediate vicinity of the measuring device, the measurement itself is greatly affected. There is a high possibility of effect.

  Further, although a technique for controlling the transmission activity of the sensor has been proposed (Non-Patent Document 3), there is a problem that communication congestion is likely to occur as the number of sensors and the number of measuring devices increase.

  It is an object of the present invention to suppress the influence of radio waves used for wireless communication on a measuring device.

  According to an aspect of the present invention, a reception unit that receives a signal from a measurement device, a radio wave emission permission period is set based on the received signal, and the radio wave is transmitted to a plurality of wireless communication devices that are communication destinations. There is provided a radio control station apparatus comprising: a control unit that performs communication control for notifying a transmission permission signal for permitting transmission within a firing permission period.

  Thereby, the influence with respect to the measuring apparatus of the electromagnetic wave used for radio | wireless communication can be suppressed.

  When the communication area in which the wireless communication device communicates is divided into a plurality of areas, the control unit is configured such that the plurality of wireless communication devices to which the transmission permission signal is simultaneously notified are the divided plurality of areas. It is preferable to perform control so as to be limited to a specific area.

  By configuring a cluster of wireless communication devices only with wireless communication devices in the same area, it is possible to minimize the influence on the measurement device in that area when wireless communication within the cluster is performed simultaneously. Is possible.

  The control unit receives the notification regarding the radio wave emission permission period from a measuring device arranged in the specific area including a plurality of wireless communication devices to which the transmission permission signal is simultaneously notified, and transmits the transmission permission signal. It is preferable to notify.

  For measurement devices belonging to the same area, the transmission permission signal is notified when the notification of the radio wave emission permission period is received from the measurement device, thereby instructing transmission permission only when the measurement device is operating. It is possible to avoid unnecessary processing when it is not operating.

  If the above-described communication area is divided into a plurality of areas by a sector antenna, the configuration may be simplified. Alternatively, the communication area may be divided into a plurality of areas by beam forming. In addition, the communication area may be divided into a plurality of areas based on the positioning result of the communication device and the measurement device as the communication destination. That is, depending on the positional relationship between the sector antenna and the measurement device based on the positioning result, one measurement device may be detected in a plurality of sectors. In this case, when examining the trigger signal of each sector for the first time, a method of processing that the measuring device is arranged in the sector having the strongest reception strength, or a plurality of detected sectors are combined into one sector. By using a method such as a handling method, it is possible to perform processing substantially equivalent to the above processing.

  The present invention may be a measuring device characterized by notifying any one of the radio control station devices described above of information relating to radio wave emission permission. Alternatively, even a wireless communication apparatus that performs communication with the radio control station apparatus according to any one of the above, and transmits to the radio control station apparatus after receiving a notification of transmission permission. good.

  According to another aspect of the present invention, there is provided a communication method in a radio control station apparatus, the step of receiving a signal from a measurement apparatus, a radio wave emission permission period is set based on the received signal, and a communication destination There is provided a communication method comprising: performing communication control for notifying a plurality of wireless communication devices of a transmission permission signal for permitting transmission within the radio wave emission permission period.

  The present invention may be a program for causing a computer to execute the communication method described above, or a computer-readable recording medium for recording the program.

  In addition, the present invention sets a radio wave emission permission period based on the reception circuit that receives a signal from the measurement device and the received signal, and the radio wave emission permission period for a plurality of wireless communication devices as communication destinations And an integrated circuit for wireless communication control, characterized by having a control circuit for performing communication control for notifying a transmission permission signal for permitting transmission.

  ADVANTAGE OF THE INVENTION According to this invention, the influence with respect to the measuring apparatus of the electromagnetic wave used for wireless communication can be suppressed.

It is a figure which shows the example of 1 structure of the radio | wireless communications system by the 1st Embodiment of this invention. In an electrocardiogram measuring apparatus, it is a figure which shows the radio wave emission permission period which can suppress the influence regarding a measurement which the sensor node may emit an electromagnetic wave from the data which self measures. It is a flowchart figure which shows the example of a communication procedure in the sink node 102 after cluster configuration. It is a functional block diagram which shows one structural example of a sink node. It is a functional block diagram which shows one structural example of a sensor node. It is a figure which shows the example of 1 structure of the radio | wireless communications system by the 2nd Embodiment of this invention. It is a figure which shows the outline | summary of the area control using a sector antenna. It is a flowchart figure which shows the flow of the trigger process of a measuring device. It is a flowchart figure which shows the procedure of clustering a sensor node, before making a sink node transmit data from a sensor no. It is a figure which shows an example of a cluster list. It is a figure which shows the procedure in which a sink node receives measurement data from each sensor node after clustering is complete | finished. It is a figure shown about operation | movement of a sensor node. It is a figure which shows the structural example of a sink node.

Hereinafter, a wireless communication technique according to an embodiment of the present invention will be described with reference to the drawings.
(First embodiment)
The wireless communication system according to the first embodiment of the present invention is a system comprising a measuring device 101, a sink node 102 for collecting data, and a plurality (many) of sensor node groups 103 as shown in FIG. is there. The sink node 102 is a node that controls the entire system, and may be referred to as a control station apparatus in this specification.

  As shown in FIG. 1, the measurement device 101 is preferably a device that is not affected by radio waves from other nodes while performing an operation such as measurement. For example, a minute bioelectricity such as an electrocardiogram measurement device is used. It is a measuring device which measures. In other words, it is suitable for the case of measuring a biological signal that is less than or equal to the influence of radio waves coming from other nodes. T1 is an object to be measured by the measuring apparatus 101.

The sink node 102 is a node that receives various data transmitted from the sensor node group 103. The sensor node 103 is a node that wirelessly transmits values such as a blood oxygen concentration (SpO ₂ ) sensor, a respiration sensor, and a blood pressure sensor. The sensor node 103 may be a device that wirelessly transmits certain information to various devices.

  In order to suppress the influence of the transmission signal of the sensor node 103 during the measurement of the measuring apparatus 101, the measuring apparatus notifies the sink node of a period during which the sensor node 103 may or may not transmit. The sink node instructs the sensor node group to transmit data. Hereinafter, the present embodiment will be described in detail with reference to the drawings, taking as an example the case where the measuring apparatus 101 is an electrocardiogram measuring apparatus.

  The electrocardiogram measuring apparatus 101 determines a period during which the sensor node 103 can emit radio waves, that is, a period during which the influence on measurement can be suppressed, from the data measured by itself. Here, this period is referred to as a radio wave emission permission period. As the radio wave emission permission period, for example, as shown in FIG. 2, a period (t1 to t2, for example, 50 ms) near the middle of two waveforms of heartbeats (waveforms at t0 and t3) can be used. Here, FIG. 2A is a heartbeat waveform, and FIG. 2B is a radio wave emission permission signal represented by a level 1 signal in the radio wave emission permission period (period from t1 to t2). The radio wave emission permission signal is a state where radio wave emission is not permitted when the level is 0, and is a state where radio wave emission is permitted when the level is 1. In this embodiment, transmission is permitted for 50 ms between heartbeats.

  In other devices that measure bioelectric current, such as an electroencephalogram measuring device and an electromyogram measuring device, it is necessary to continuously observe the waveform. In such a case, in order to provide the radio wave emission permission period, for example, it is possible to use a method in which a period in which measurement is not performed for 100 ms every minute is determined and the period is allocated.

  A radio wave emission permission signal is input to the sink node 102, and transmission of the sensor node 103 is permitted in units of clusters in which a plurality of sensor nodes 103 are combined. It is assumed that numbers are assigned to the clusters, for example, 0 to N in ascending order. The upper limit number of sensor nodes 103 included in the cluster is the number that can be demodulated simultaneously by the sink node 102, for example, four. In the present embodiment, the cluster configuration is set in advance before the start of communication, but may be set later using another communication procedure. In addition, the sensor node 103 included in the cluster is assigned an intra-cluster ID, and uses a preamble corresponding to the intra-cluster ID at the time of transmission.

  FIG. 3 is a flowchart showing an example of a communication procedure in the sink node 102 after the cluster configuration.

  As shown in FIG. 3, in step S101, a counter for managing the transmission cluster number is initialized (cleared to 0). Next, in step S102, the process waits until the radio wave emission permission signal becomes 1, and when it becomes 1, the process proceeds to step S103. In step S103, a transmission permission signal is transmitted to the sensor node included in the cluster indicated by the current transmission cluster number counter. Thereafter, in step S104, signals simultaneously transmitted from the sensor nodes are received and demodulated, and data is collected. Subsequently, in step S105, it is determined whether there is an untransmitted cluster, that is, whether the transmission cluster number is less than N. If a transmission permission signal is transmitted to all clusters and there is no untransmitted cluster (cluster number) = N), (N) return to step S101 to initialize the cluster number counter. If there is an untransmitted cluster (when cluster number <N), the process proceeds to (Y) step S106. In step S106, the current transmission cluster number counter is incremented by 1, and the process returns to step S102 to perform processing for the next cluster.

  By performing the processing as described above, it is possible to transmit simultaneously from a plurality of sensor nodes during the radio wave emission permission period determined by the measuring device, and efficiently suppress the influence on the measuring device while minimizing the influence on the measuring device. Data packet collection from can be performed.

  4 and 5 are functional block diagrams showing an example of the configuration of a sink node and a sensor node for realizing the procedure of FIG.

  FIG. 4 is a functional block diagram illustrating a configuration example of the sensor node. The sensor node extracts the necessary band from the RF signal received by the antenna unit 501, the antenna unit 501, the switching unit 502 that switches the connection destination of the antenna unit 501 to the RF receiving unit 503 or the RF transmitting unit 512, and the antenna unit 501, RF receiving section 503 for converting to a baseband signal, propagation path estimating section 504 for estimating received signal timing and propagation path information from the preamble included in the received signal, received signal timing and propagation estimated by propagation path estimating section 504 Demodulator 505 that demodulates data from received signal using path information, CRC detector that calculates CRC of demodulated data and detects whether the value is equal to the value included in the demodulated data 506, a control unit 507 for controlling each unit and managing communication data to be transmitted and received, and calculating CRC of transmission data And a CRC adding unit 508 to be added, a preamble selecting unit 509 for selecting a preamble in a format instructed by the control unit 507, and a preamble for adding the preamble selected by the preamble selecting unit 509 to a signal output from the CRC adding unit 508. Modulating section 511 that modulates the output of adding section 510 and preamble adding section 510 and converts it to a baseband signal, converts the baseband signal output from modulating section 511 to an RF frequency for transmission from antenna section 501, and power An RF transmission unit 512 that performs amplification is included. It is possible to replace some components with other components, or to realize a plurality of functions with one circuit.

  The control unit 507 switches the switching unit 502 to the RF receiving unit 503 side except when transmitting data, and receives a signal transmitted from the sink node. Further, the control unit 507 prepares data to be transmitted at the next transmission opportunity from communication data including measurement data. The control unit 507 has a cluster ID set in advance or by some method and a preamble set uniquely in the cluster. Then, a preamble set uniquely within the cluster is set in the preamble setting unit 509.

  When the data sent from the sink node includes a transmission permission signal for the cluster including itself, the control unit 507 outputs the prepared transmission data to the CRC adding unit 508, and The switching unit 502 is switched to the RF transmission unit 512. The transmission data is modulated after the CRC and preamble are added, converted to an RF frequency, and then transmitted from the antenna 501 unit. The control unit 507 waits for all transmission data to be transmitted, and switches the switching unit 502 to the RF receiving unit 503 side.

  By repeating the above operation, communication data including measurement data can be transmitted to the sink node when a transmission permission signal is transmitted from the sink node.

  Next, the configuration of the sink node will be described with reference to FIG. Reference numerals 601 to 604 denote the antenna 1 to the antenna 4 for receiving the RF signal, and reference numerals 605 to 608 denote the RF receiver 1 to the RF receiver 4 for converting the received RF signal into a baseband signal. Reference numeral 609 denotes a preamble detected from a baseband signal output from the RF receiver (1) 605 to the RF receiver (4) 608 using a correlator, and a packet transmitted from the sensor node. A propagation path estimation unit that measures timing and measures propagation path characteristics (transfer function) between the sensor node and the sink node. Reference numeral 610 denotes a packet timing measured by the propagation path estimation unit 609 and propagation path information. Reference numeral 611 denotes an instruction from the control unit 612 and a parameter measured by the propagation path estimation unit 609. The CRC detection unit calculates the CRC of the demodulated output of the demodulator 610 using the timing of the transmission signal. Reference numeral 612 indicates reception signal selection, demodulation method selection, and reception using the output of the propagation path estimation unit during reception. CRC control of a packet to be transmitted, an operation of outputting received data to the outside, and a control unit that controls each unit to configure a transmission bucket at the time of transmission. Reference numeral 613 denotes a transmission packet configured by the control unit 612 A CRC adding unit for adding a CRC to the transmission packet. Reference numeral 615 denotes a preamble adding unit for adding a preamble set by the control unit 612 to a transmission packet to which a CRC is added by the CRC adding unit 613. Reference numeral 616 denotes an addition of the preamble. Is a modulation unit that modulates the transmitted packet and converts it into a baseband signal. Reference numeral 617 transmits a baseband signal. Convert the required frequency band, RF transmission section for amplifying the electric power is predetermined, 618 is a transmitting antenna for transmitting an output signal of the RF transmission unit 617 as a radio wave.

  The control unit 612 has a transmission permission signal input 619 for inputting a transmission permission signal output from the measuring apparatus, and performs an operation according to the input transmission permission signal. Since the overall operation is as shown in FIG. 3, the following describes how each block operates during transmission and reception.

  When transmitting a signal, the control unit 612 generates transmission data, outputs the transmission data to the CRC adding unit 613, and operates the RF transmission unit 617. The transmission data is CRC-added by a CRC adding unit 613, a preamble is added by a preamble adding unit 615, converted to a baseband signal by a modulating unit 616, converted to a frequency necessary for transmission by an RF transmitting unit, and amplified. It is transmitted from the transmission antenna 618 later. The control unit 612 stops the operation of the RF transmission unit 617 at the timing when transmission of transmission data ends.

When receiving a signal, it is necessary to demodulate the signals transmitted simultaneously by the sensor nodes in the cluster. Although there are various methods as described above, in this embodiment, the demodulation by the zero forcing method will be described.
The control unit 612 transmits the preamble used by the nodes included in the received cluster to the propagation path estimation unit 609 and the demodulation unit 610. The propagation path estimation unit 609 detects the preamble transmitted from the sensor node group included in the signal received from each receiving antenna, and measures the signal reception timing and the transfer function between each sensor node and each receiving antenna.

  The demodulator 610 demodulates the signal thus separated, calculates the CRC of the signal input by the CRC detector input to the CRC detector 611, and inputs it to the controller 612 together with the signal input to the CRC detector 611. Is done. If the CRC included in the demodulated data is equal to the calculated CRC, the received data is output assuming that the data packet has been normally received.

  The flow shown in FIG. 4 is realized by the operation of each block as described above, and uplink communications from a plurality of sensor nodes to the sink node are simultaneously multiplexed and transmitted during the radio wave emission permission period determined by the measurement device. By doing so, it is possible to efficiently collect data packets from the sensor node while minimizing the influence on the measuring apparatus.

(Second Embodiment)
Next, a second embodiment of the present invention will be described. In the present embodiment, as shown in FIG. 6, there are a plurality of measuring devices 202 and 204 around the sink node 201, and each measuring device wirelessly notifies the sink node 201 of the radio wave emission permission period. Will be described. As in the first embodiment, various sensor nodes are also arranged, the first sensor node group 203,... Around the measuring device 202, and the second sensor node group 205 around the measuring device 204. ... shall be arranged. T2 is a measurement object of the measurement device 202, and T3 is a measurement object of the measurement device 204.

  Since the radio wave emission permission periods of the measurement device 202 and the measurement device 204 are not necessarily synchronized, the method described in the first embodiment cannot be applied as it is.

  However, the electric field and magnetic field radiated from the transmitting antenna are large in the vicinity of the antenna and may affect the measuring apparatus, but both the electric field and the magnetic field rapidly decrease as the distance from the antenna increases. Therefore, although depending on the transmission power, the radio wave emission permission is controlled in area units in this embodiment by utilizing the fact that the electric field and magnetic field are reduced to such an extent that they do not affect when they are separated by a certain distance.

  Various methods can be used as the area control method, but in this embodiment, area control using a sector antenna is performed. An outline of area control using a sector antenna will be described with reference to FIG.

  FIG. 7 shows an example in which the number of sectors is 3, and two measurement apparatuses are used. The number of sectors is not limited to 3, and may be 2 or may be divided into more sectors. 701 is a sink node, 702 is a sink node omnidirectional antenna for multi-user reception, 703 is a sector antenna composed of a plurality of directional antennas, 704, 705 and 706 are areas divided by the sector antenna, 707, Reference numeral 708 denotes a measuring device, and reference numerals 709 and 710 denote various sensor node groups. It is assumed that the measuring devices 707 and 708 are arranged at separate positions and are included in another sector. As a result, the area 704 includes the measuring device 707 and the sensor node group 709, and the area 705 includes the measuring device 708 and the sensor node group 710. The sensor node group 709 performs clustering therein, and the sensor node group 710 also performs clustering therein. Further, the number of measuring devices in the area is 1 or less.

  As described above, configuring the cluster of sensor nodes only with sensor nodes in the same area minimizes the effect on sensor devices in other areas when sensor nodes in the cluster transmit at the same time. It becomes possible to suppress. When the transmission permission signal is notified to the sensor nodes in the cluster, the trigger signal of the measuring device in the same area is referred to.

  Hereinafter, a procedure for configuring a cluster from the state of the arranged measuring apparatus and sensor node and collecting data from the sensor node will be described in detail with reference to the drawings.

  First, it is assumed that a measuring device and a sensor node constituting a network are registered in advance in a sink node, and a unique ID is attached at that time. Wired connection technology such as USB connection can be used for registration.

  The measuring devices 707 and 708 measure the measurement object, determine the radio wave emission permission period during which the sensor nodes 709 and 710 are allowed to emit radio waves from the measured data, and at the same time when the radio wave emission permission period is reached. A trigger signal is transmitted to the sink node 701. FIG. 8 shows the flow of such processing.

  As shown in FIG. 8, in the trigger process of the measuring apparatus, first, the measurement target is measured in step S201, and the radio wave emission permission period is determined in step S202. Thereafter, in step S203, the start of the radio wave emission permission period is waited. When the start time is reached, in step S204, it is checked whether another node or measurement device is transmitting. If another node or measurement device is transmitting (Y), the process returns to step S201. If another node or measurement device is not transmitting (N), the process proceeds to step S205, and the length of the radio wave emission permission period and the trigger signal including the ID assigned to itself are transmitted to the sink node. To do. Then, it returns to step S201 and performs the same process.

  The measuring devices 707 and 708 periodically transmit a trigger signal to the sink node 701 by performing the operation of the flow shown in FIG. Each of the two measuring devices 707 and 708 performs the processing shown in FIG. 8 and transmits a trigger signal when other measuring devices 708 and 707 and other sensor nodes 710 and 709 are transmitting. By stopping, it is possible to prevent the transmission periods of sensor nodes in different areas from overlapping when the radio wave emission periods overlap.

  Next, a procedure for clustering the sensor nodes 709 and 710 before the sink node 701 transmits data from the sensor nodes 709 and 710 will be described with reference to FIG.

  First, it is assumed that a trigger signal is transmitted from the measuring devices 707 and 708. Then, first, in step S301, it is checked whether or not the measuring apparatus that receives the sector 1 for a predetermined time and transmits the trigger signal is in the sector. Next, in step S302, for sector 2 as well, it is checked whether or not the measuring device that is transmitting the trigger signal is in the sector. Subsequently, in step S303, similarly for sector 3, it is checked whether or not the measuring apparatus transmitting the trigger signal is in the sector.

  In step S304, a sector counter indicating the processing sector is initialized (sector counter = sector 1). Next, in step S305, it is checked whether there is a measuring device in the sector indicated by the sector counter. If there is no measuring device, the process proceeds to step S309, and if there is a measuring device, the process proceeds to step S306.

  In step S306, the process waits for a trigger signal to be transmitted from the target measurement device, confirms that the trigger signal has been transmitted from the target measurement device, and proceeds to step S307. In step S307, an inquiry command is transmitted to the target sector. The inquiry command is a command for requesting transmission of an inquiry response to all sensor nodes in the sector. By receiving an inquiry response transmitted by each node in the sector in step S308, the inquiry command is received in the sector. It is possible to know which sensor node is arranged. Subsequently, in step S309, the sector counter is incremented by one, and in step S310, an inquiry command is transmitted to all sectors, that is, whether the sector counter indicates sector 4 is checked. Return to. If it is sector 4, it is assumed that the inquiry command has been transmitted to all sectors, and the process proceeds to step S311.

  In step S311, a cluster is configured in each sector. The cluster is configured not to exceed the number of nodes that the sink node can receive at one time, for example, four.

  Subsequently, in order to transmit a cluster list to each sector, a sector counter is initialized in step S312. In step S313, it is checked whether there is a measurement device in the target sector. If there is no measurement device, the process proceeds to step S316, and if there is a measurement device, the process proceeds to step S314. In step S314, the process waits until a trigger signal is transmitted from the measuring device, confirms that the trigger signal has been transmitted, and proceeds to step S315. In step S315, the cluster list is transmitted to the target sector. The cluster list is a list describing which node belongs to which cluster, and also shows the intra-cluster ID.

  An example of the cluster list is shown in FIG. This intra-cluster ID represents which preamble is used when the sensor nodes in the cluster broadcast. After the transmission of the cluster list, the process proceeds to step S316. In step S316, the sector counter is incremented by 1. In step S317, it is determined whether or not the transmission of the cluster list has been completed for all the measuring apparatuses (sector counter = sector 4). If YES in step S313, the process returns to step S313, and if completed, clustering of the sink node ends.

  Next, a procedure in which the sink node receives measurement data from each sensor node after clustering is completed will be described with reference to FIG. First, in step S401, it is monitored whether a trigger signal is transmitted in all sectors, and it is determined whether a trigger signal is received in step S402. If not received, the process returns to step S401, and if received, the process proceeds to step S403. In step S403, a transmission permission signal is transmitted to the cluster included in the sector from which the trigger signal is received. When there are a plurality of clusters included in the sector from which the trigger signal is received, a transmission permission signal is sequentially transmitted to one cluster in one trigger signal. After transmitting the transmission permission signal, the signal transmitted from the cluster is received in step S404, and the process returns to step S401. By repeating the above procedure, the sink node receives measurement data from each sensor node.

  Next, the operation of the sensor node will be described with reference to FIG. First, in step S501, the transmission from the sink node is awaited. If a signal is received, the process proceeds to step S502. In step S502, it is determined whether the received signal is an inquiry command. If the received signal is an inquiry command, the process proceeds to step S503. If the received signal is not an inquiry command, the process proceeds to step S506. If it is an inquiry command, it is checked in step S503 whether another node is transmitting. If it is transmitting, the process proceeds to step S504. If not, the process proceeds to step S505. In step S504, a random time is waited, and the process returns to step S503. In step S505, an inquiry response including its own ID is transmitted to the sink node, and the process returns to step S501.

  In step S506, it is determined whether the received signal is a cluster list. If the received signal is a cluster list, the process proceeds to step S507. If not, the process proceeds to step S508. In step S507, the cluster list in the own node is replaced with the received cluster list, and the cluster ID to which the node belongs and the intra-cluster ID are confirmed. Thereafter, the process returns to step S501.

  In step S508, it is determined whether or not the received signal is a transmission permission signal. If it is a transmission permission signal, the process proceeds to step S509. If it is not a transmission permission signal, the process returns to step S501. In step S509, it is determined whether or not the received transmission permission signal is addressed to the cluster ID to which it belongs. If it is addressed to the cluster ID to which it belongs, the process proceeds to step S510, and if it is not addressed to the cluster ID to which it belongs. The process returns to step S501. In step S510, the measurement data is transmitted to the sink node using the preamble corresponding to the intra-cluster ID assigned to itself, and then the process returns to step S501.

  By repeating the above operation, the sensor node transmits measurement data to the sink node.

  In addition, since the sink node and the sensor node perform the above-described operations, the trigger signal and the corresponding transmission permission signal are handled in units of areas, so that when a trigger signal is transmitted in one area, the sensor in another area The node does not transmit and does not affect the measuring device in another area. In addition, since transmission is performed simultaneously from multiple sensor nodes in the area, measurement data can be collected efficiently, and the frequency of transmission can be reduced by simultaneous transmission. It becomes possible.

  Next, a configuration example of an apparatus for performing the operation described above will be described with reference to the drawings. First, regarding the sensor node, the same configuration as that of the first embodiment, that is, the configuration shown in FIG. 5 can be used. The control unit 507 operates each block according to the flow shown in FIG.

  Next, a configuration example of the sink node will be described with reference to FIG. The configuration example of FIG. 13 is a configuration in which the configuration example of the first embodiment, that is, the configuration example of FIG. 5 is slightly changed. Blocks whose configurations and operations are the same as those in FIG. 5 are given the same reference numerals as in FIG. Reference numeral 1301 indicates reception signal selection using the output of the propagation path estimation unit at the time of reception, selection of a demodulation method, CRC determination of a received packet, and operation of outputting reception data to the outside. Reference numeral 1302 denotes an antenna switching unit (1) for switching which antenna is a connection destination of a transmission signal, and reference numeral 1303 is an RF transmission unit 617 for connection of a sector antenna. An antenna switching unit (2) for switching between the RF receiving unit (4) 608 and a reference numeral 1304 switches between an omnidirectional receiving antenna (4) 604 and a sector antenna 1305 as an antenna connected to the RF receiving unit 4. Reference numeral 1305 denotes an antenna switching unit (3), which is a sector antenna that can select a communication range using a plurality of directional antennas.

  When the processing shown in the flow of FIG. 9 is performed, the control unit 1301 first sets the antenna switching unit (2) 1303 and the antenna switching unit (3) 1304 when checking the presence / absence of a trigger signal in each sector, and performs RF reception. The sector antenna 1305 is connected to the unit (4). Next, the antenna switching unit (1) is set, the sector to be checked for the presence or absence of the trigger signal is selected, and the presence or absence of the trigger signal is checked using the RF receiver (4) 608.

  After checking the presence or absence of the trigger signal, the antenna switching unit (3) 1304 is set so that the omnidirectional receiving antenna (4) 604 is connected to the RF receiving unit (4) 608. Also, the antenna switching unit (2) 1303 is set so that the sector antenna is connected to the RF transmission unit 617. Thereafter, the control unit 1301 sets the antenna switching units 1 and 1302 to switch the transmission destination sector, and executes the flow of FIG.

  When the flow of FIG. 11 is performed, the antenna switching unit (3) 1304 is set so that the non-directional receiving antenna (4) 604 is connected to the RF receiving unit (4) 608. Also, the antenna switching unit (2) 1303 is set so that the sector antenna is connected to the RF transmission unit 617. The reception of the trigger signal uses an omnidirectional antenna, but the sector signal transmitted from which sector signal is compared by comparing the trigger signal data checked when performing the flow of FIG. 9 with the ID included in the received trigger signal. Can be distinguished.

  For other blocks, the same operation as in FIG. 6 is performed. As a result, the flow of FIG. 9 and the flow of FIG. 11 can be performed.

  In the present embodiment, it is assumed that one measuring device is detected in one sector. However, depending on the positional relationship based on the positioning result between the sector antenna and the measuring device, one measuring device may include a plurality of sectors. May be detected. In this case, in the flow of FIG. 9, when examining the trigger signal of each sector for the first time, a method of processing that the measuring device is arranged in the sector with the strongest reception strength, or a plurality of detected sectors. By using a method such as a method of handling them as a single sector, it is possible to perform processing substantially equivalent to the above processing.

  In addition, when the number of sectors is large, there is a possibility that sensor nodes around the measuring apparatus cannot fit in one sector. In such a case, when configuring a cluster, it is possible to include sensor nodes arranged in adjacent sectors in the same cluster, thereby enabling processing substantially equivalent to the processing described. In addition, there may be a case where there is no measurement device in the sector including the sensor node and the adjacent sector. In such a case, the sector including the sensor node may be controlled independently, or may be treated as one sector together with any sector including the measurement device.

  In the above-described embodiment, the configuration and the like illustrated in the accompanying drawings are not limited to these, and can be changed as appropriate within the scope of the effects of the present invention. In addition, various modifications can be made without departing from the scope of the object of the present invention.

  In this embodiment, sector antennas are used for area control, but the same may be performed using a beam forming technique using a plurality of antennas. In addition, the position of the measuring device that sends the trigger signal using the positioning technology such as TDOA (Time Difference Of Arrival) technology, as well as the position of the sensor node is directly measured, and the sensor nodes near the measuring device are clustered. The flow shown in FIG. 11 may be applied.

  In the present embodiment, the measurement device is distinguished from the sensor node. However, a configuration that serves as both the measurement device and the sensor node is also possible. In this case, the ID of the measuring device is included in the cluster map, and the other operations may be performed in the same manner. Alternatively, a method of including measurement data in the trigger signal is also possible.

  In the present embodiment, one or less measuring devices are arranged in one area. However, when the measuring devices can be synchronized, a plurality of measuring devices may be arranged in one area. . At this time, a plurality of synchronized measuring devices can be regarded as one measuring device.

  In addition, a program for realizing the functions described in the present embodiment is recorded on a computer-readable recording medium, and the program recorded on the recording medium is read into a computer system and executed to execute processing of each unit. May be performed. The “computer system” here includes an OS and hardware such as peripheral devices.

  Further, the “computer system” includes a homepage providing environment (or display environment) if a WWW system is used.

  The “computer-readable recording medium” refers to a storage device such as a flexible medium, a magneto-optical disk, a portable medium such as a ROM and a CD-ROM, and a hard disk incorporated in a computer system. Furthermore, the “computer-readable recording medium” dynamically holds a program for a short time like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line. In this case, a volatile memory in a computer system serving as a server or a client in that case, and a program that holds a program for a certain period of time are also included. The program may be a program for realizing a part of the above-described functions, or may be a program that can realize the above-described functions in combination with a program already recorded in a computer system.

  Further, a part or all of the devices in the above-described embodiments may be realized as an integrated circuit such as an LSI (Large Scale Integration). Each functional block of the apparatus may be individually made into a processor, or a part or all of them may be integrated into a processor. Further, the method of circuit integration is not limited to LSI, and may be realized by a dedicated circuit or a general-purpose processor. Further, in the case where an integrated circuit technology that replaces LSI appears due to progress in semiconductor technology, an integrated circuit based on the technology may be used.

  The present invention is applicable to a wireless communication device.

DESCRIPTION OF SYMBOLS 101 ... Measuring apparatus, 102 ... Sink node, 103 ... Sensor node group 103, 501 ... Antenna part, 503, 512 ... RF receiving part, 502 ... Switching part, 504 ... Propagation path estimation part, 505 ... Demodulation part, 506 ... CRC Detection unit, 507 ... control unit, 508 ... CRC addition unit, 509 ... preamble selection unit, 510 ... preamble addition unit, 511 ... modulation unit, 512 ... RF transmission unit 512, 601 to 604 ... antenna, 605 to 608 ... RF reception 609... Propagation path estimation unit, 610... Demodulation unit, 611... CRC detection unit, 612... Control unit, 613... CRC addition unit, 615 ... Preamble addition unit, 616 ... Modulation unit, 617 ... RF transmission unit, 618: Transmitting antenna.

Claims (11)

A receiver for receiving a signal from the measuring device;
Communication control for setting a radio wave emission permission period based on the received signal and notifying a plurality of communication destination wireless communication devices of a transmission permission signal for permitting transmission within the radio wave emission permission period. And a control unit that performs the control. The controller is
When the communication area in which the wireless communication device communicates is divided into a plurality of areas,
2. The radio control station according to claim 1, wherein a plurality of radio communication apparatuses to which the transmission permission signal is simultaneously notified are controlled to be limited to a specific area of the plurality of divided areas. apparatus. The controller is
Receiving the notification regarding the radio wave emission permission period from the measurement device arranged in the specific area including the plurality of wireless communication devices to which the transmission permission signal is simultaneously notified, and notifying the transmission permission signal. The radio control station apparatus according to claim 2.   The radio control station apparatus according to claim 2 or 3, wherein the communication area is divided into a plurality of areas by a sector antenna.   The radio control station apparatus according to claim 2 or 3, wherein the communication area is divided into a plurality of areas by beam forming.   The radio control station apparatus according to claim 2 or 3, wherein the communication area is divided into a plurality of areas based on a communication result of a communication destination and a measurement apparatus.   A measurement apparatus that notifies the radio control station apparatus according to any one of claims 1 to 6 of information related to radio wave emission permission.   A radio communication apparatus that performs communication with the radio control station apparatus according to any one of claims 1 to 6 and performs transmission to the radio control station apparatus after receiving a notification of transmission permission. . A communication method in a radio control station apparatus,
Receiving a signal from the measuring device;
Communication control for setting a radio wave emission permission period based on the received signal and notifying a plurality of communication destination wireless communication devices of a transmission permission signal for permitting transmission within the radio wave emission permission period. A communication method comprising the steps of:   A program for causing a computer to execute the communication method according to claim 9. A receiving circuit for receiving a signal from the measuring device;
Communication control for setting a radio wave emission permission period based on the received signal and notifying a plurality of communication destination wireless communication devices of a transmission permission signal for permitting transmission within the radio wave emission permission period. An integrated circuit for controlling wireless communication, comprising: a control circuit for performing control.

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