JP5808209B2 - Adaptive modulation coding method and apparatus - Google Patents

Description

  The present invention relates to a wireless communication system and a wireless communication apparatus, and more particularly to a communication control technique using adaptive modulation and coding.

  In recent years, there has been an increasing demand for remotely monitoring and maintaining facilities such as boilers and thermal turbines, or monitoring energy consumption on the premises remotely from the center side away from the site. At this time, if a communication cable is connected to each terminal monitoring sensor, the cost increases and the monitoring target may move. Therefore, the sensor data is temporarily collected in the base station apparatus by wireless communication. The configuration is drawing attention.

  On the other hand, generally, wireless communication has a larger variation in propagation path quality than wired communication. In contrast, an adaptive modulation and coding scheme that increases the amount of transmission data while maintaining the packet arrival rate by adaptively selecting a modulation and coding scheme (MCS) according to the channel quality. (AMC: Adaptive Modulation and Coding) is known. Also in the remote monitoring system, the communication speed per sensor can be improved and the communication time can be shortened by applying AMC.

  In order to further enhance the effect of AMC, various methods have been proposed for the selection of MCS. For example, Patent Document 1 and Patent Document 2 increase the total number of MCS candidates by measuring the average channel quality of the terminal and selecting a set of MCS candidates for AMC centering on the MCS corresponding to the quality. A technique for enhancing the effect of AMC without doing so is disclosed. Patent Document 2 discloses a technique for switching an average time of received signal quality (SINR: Signal to Interference and Noise Ratio) used for MCS determination according to a moving speed of a terminal measured by a base station apparatus. . Patent Document 3 discloses a technique for reducing the influence of short-term channel fluctuation (fading) by applying an offset according to the current packet error rate to the threshold value of the correspondence table between SINR and MCS. It is disclosed. Further, Patent Document 4 discloses a technique for reducing the influence on the AMC of the hidden terminal problem in CSMA (Carrier Sense Multiple Access) by exchanging information of a communication destination node between nodes. Further, Patent Document 5 discloses a technique for reducing the processing load of blind decoding by performing blind decoding in order from a higher-order modulation scheme and terminating at a successful time.

JP 2010-081594 A JP 2011-049829 A JP-A-2005-204276 JP 2009-177481 A JP 2004-519178 A

  In AMC in which the transmission side selects one of a plurality of MCS candidates, in order for reception processing such as demodulation and decoding to succeed, the reception side needs to perform reception processing using the MCS selected by the transmission side. This can be realized, for example, when the transmitting side notifies the receiving side of MCS information separately from the data. In this case, the reception side load is low because it is sufficient to perform the reception process with the notified MCS, but the amount of transmission data increases by the amount of MCS information, and the transmission side load increases by the amount of the transmission processing and transmission time. Become. On the other hand, the transmission side may not notify the MCS information, and the reception side may try reception processing for all candidate MCSs (blind decoding). In this case, the load on the transmission side is equivalent to the case where AMC is not performed, but the reception processing is repeated until success, so the processing load on the reception side increases. As described above, it is a problem of AMC that the load on either the transmission side or the reception side becomes high in order to match the MCS.

  Patent Documents 1-4 all increase the effect of AMC, and cannot reduce the processing load. Further, in Patent Document 5, when the transmission side uses a low-order modulation scheme, almost all MCSs are received and when it is mistakenly received that a higher-order MCS is received, the lower-order MCS is received. Therefore, there is a problem that the AMC is canceled without being received.

  In order to solve the above problems, an object of the present invention is to provide an adaptive modulation and coding method and apparatus in which both processing loads on the transmission side and the reception side are low.

In order to achieve the above object, according to the present invention, there is provided an adaptive modulation and coding method in a system in which wireless communication is performed on a transmission side and a reception side, and a common propagation path that can be measured independently on a transmission side and a reception side. Based on the quality information measured independently on each of the transmission side and the reception side, and on the basis of the shared transition condition, the transmission side and the reception side each modulate and encode. The receiving side selects a part of the candidate modulation and coding schemes as the target of reception processing, and temporarily determines the number of modulation and coding schemes to be subject to reception processing during operation according to the judgment of the receiving side. The condition for increasing the number of modulation and coding schemes to be received and increasing the number of modulation and coding schemes to be received is the period from when the modulation and coding scheme is switched until a predetermined number of packets are received in advance. Modulation coding method Subjected to.

In order to achieve the above object, according to the present invention, an aggregation station apparatus that performs radio communication with a measurement terminal apparatus, and includes a radio transmission / reception unit and a processing unit that use a modulation and coding scheme, Transition conditions of modulation and coding schemes using the quality information of a common channel that can be measured independently by the aggregation station device and the measurement terminal device shared with the terminal device, and the quality measured independently by the aggregation station device Based on the information, the modulation and coding schemes are switched, and a part of the candidate modulation and coding schemes are targeted for reception processing . A condition in which the condition for temporarily increasing the number and increasing the number of modulation and coding systems to be received is a period from when the modulation and coding system is switched until a predetermined number of packets are received in advance Provide central station equipment .

Furthermore, in order to achieve the above object, in the present invention, a measurement terminal apparatus that performs radio communication with an aggregation station apparatus, comprising a radio transmission / reception unit and a processing unit that use a modulation and coding scheme, Transition conditions of modulation and coding schemes using as an index the quality information of a common channel that is received from a station apparatus and shared with the aggregation station apparatus and can be measured independently by the measurement terminal apparatus and the aggregation station apparatus, and the measurement It switches the modulation and coding scheme based on the quality information measured independently by the terminal device, the processing unit, during operation, temporarily increasing the number of modulation and coding scheme to be subjected to reception processing, target reception processing The measurement terminal apparatus is configured such that the condition for increasing the number of modulation and coding schemes is a period from switching of the modulation and coding schemes to receiving a predetermined number of packets in advance .

  According to the present invention, it is possible to match the MCS used for transmission processing and reception processing in an autonomous distributed manner, and the reception side can limit the MCS that performs reception processing even if the transmission side does not notify the MCS information. Thereby, it is possible to provide an adaptive modulation and coding scheme in which the processing load on both the transmission side and the reception side is low.

1 is an overall configuration diagram of a remote monitoring system in each embodiment. It is a figure which shows the operation | movement sequence of AMC of the form which a transmission side notifies MCS information. It is a figure which shows the operation | movement sequence of AMC of the form which a receiving side designates MCS. It is a figure which shows the operation | movement sequence of AMC of the form which does not exchange MCS information. It is a figure which shows the operation | movement sequence of the remote monitoring system of a 1st Example. It is a figure which shows an example of the MCS transition condition table shared in each Example. It is a figure which shows the operation | movement flowchart of the measurement terminal in a 1st Example. It is a figure which shows the operation | movement flowchart of the measurement information collection station in a 1st Example. It is a figure which shows the operation | movement flowchart of the measurement terminal in a 2nd Example. It is a figure which shows the operation | movement flowchart of the measurement information aggregation station in a 2nd Example. It is a figure which shows the operation | movement sequence of the dynamic / remote monitoring system of a 3rd Example. It is a figure which shows the operation | movement flowchart of the measurement terminal in a 3rd Example. It is a figure which shows the operation | movement flowchart of the measurement information aggregation station in a 3rd Example. It is a figure which shows the operation | movement sequence of the remote monitoring system of a 4th Example. It is a figure which shows the operation | movement flowchart of the measurement information aggregation station in a 4th Example. It is a figure which shows the operation | movement flowchart of the measurement information collection station in a 5th Example. It is a figure which shows an example of the functional block of the measurement terminal in each Example. It is a figure which shows an example of the apparatus structure of the measurement terminal in each Example. It is a figure which shows an example of the functional block of the measurement information aggregation station in each Example. It is a figure which shows an example of the apparatus structure of the measurement information aggregation station in each Example.

  Hereinafter, various embodiments of the present invention will be described with reference to the drawings. In the drawings, the same reference numerals indicate the same operation, and therefore description thereof is omitted. In this specification, a transmission path evaluation index is referred to as transmission path quality information or simply quality information. The various embodiments described below will be described by exemplifying a remote monitoring system that monitors measurement information such as sensors at a monitoring center. However, the present invention is used for other communication devices that use wireless communication. Is possible.

  FIG. 1 shows an overall configuration diagram of a remote monitoring system in each embodiment. The remote monitoring system in each embodiment includes a measurement information aggregation station 101 and a measurement terminal 102 connected via a wireless network 105, a network 104 and a monitoring center 103 connected to the measurement information aggregation station 101 via the network 104. . The network 104 may be a local network or a wide area network. The measurement information aggregation station 101 is, for example, a base station device of a wireless network, and the measurement terminal 102 is, for example, a sensor terminal device of a wireless network.

  The measurement information aggregation station 101 has a communication function with the monitoring center 103 via the network 104 and a communication function with one or a plurality of measurement terminals 102 via the wireless network 105. The measurement information aggregation station 101 has a function of aggregating sensor measurement information notified from one or a plurality of measurement terminals 102 via the wireless network 105 and notifying the monitoring center 103 via the network 104. In addition, the measurement information aggregation station 101 may have a function of changing the operation of the measurement terminal 102 through the wireless network 105 in accordance with control from the monitoring center 103 through the network 104.

  The measurement terminal 102 has a sensor function and a wireless communication function. The measurement terminal 102 performs measurement using the sensor function, and notifies the measurement information aggregation station 101 via the wireless network 105 of sensor measurement information obtained as a result of the measurement. Here, the sensor function is a sensor that can operate independently, such as a temperature sensor, a humidity sensor, and an acceleration sensor, or a sensor that uses an external signal input such as a position sensor using GPS, or a voice or still image. , Any of the monitoring devices that acquire moving images, or a combination. In addition, the measurement terminal 102 may have a function of changing the operation of either or both of the sensor function and the wireless communication function in accordance with the control from the measurement information aggregation station 101. The function changed here is, for example, the type of sensor used for measurement in the sensor function, the frequency of measurement in the sensor function, or the frequency of communication in the wireless communication function.

  The monitoring center 103 has a network communication function, and receives sensor measurement information collected by the measurement information collection station 101 through the network 104. The monitoring center 103 may have one or more of a storage device that stores the received sensor measurement information, an analysis device that analyzes the sensor measurement information, and a display device that displays the sensor measurement information. The monitoring center 103 may have a function of controlling the operation of one or both of the measurement information aggregation station 101 and the communication terminal 102. The monitoring center 103 having such a configuration and function has a normal network communication function, and can be configured by a computer having a CPU (Central Processing Unit) as a processing unit, a memory as a storage unit, and a display as a display unit. In addition, the functions and control functions as the analysis device described above can be realized by program processing by the CPU.

  The network 104 is, for example, a LAN using IEEE802.11 or IEEE802.3 for a physical layer, or a MAN (Metropolitan Area Network) using IEEE802.16 for a physical layer, or a cellular network, or It is a wireless or wired network consisting of a combination.

  The wireless network 105 is, for example, a PAN (Personal Area Network) using IEEE 802.15.4 or a specific low power wireless system for the physical layer, or a LAN (Local Area Network) using IEEE 802.11 for the physical layer, for example. Or a cellular network, or a combination thereof.

  Hereinafter, the description will be made on the premise that IEEE802.15.4 is used for the physical layer of the wireless network 105 and IEEE802.3 LAN is used for the physical layer of the network 104. Each embodiment can be applied to other combinations than the above. Further, as described above, the configuration of collecting data from the sensor terminals via the wireless network 105 in the remote monitoring system is mainly targeted, and the transmitting side is the measuring terminal 102 and the receiving side is the measurement information collecting station 101. The measurement information aggregation station 101 has a coordinator function in IEEE 802.15.4. Unless otherwise specified, when the MCS is updated, the error count is initialized.

  Various operation modes of the AMC method will be described with reference to FIGS. For simplification of description, only one processing flow is described in the following operation sequence, but a plurality of processing flows may be executed in a pipeline manner.

  FIG. 2 shows an operation sequence of the AMC method in which the transmission side notifies the MCS information. When the power-on process 201 is performed, the measurement terminal 102 first notifies the measurement information aggregation station 101 of a subscription request 202 for PAN. The measurement information aggregating station 101 determines whether the measurement terminal 102 can be added to the PAN managed by the measurement information aggregation station 101 (203), and notifies the subscription permission 204 if possible. The subscription request 202 and the subscription permission 204 correspond to an Association Request and an Association Response in IEEE 802.15.4, respectively. As described above, the measurement terminal 102 is added to the PAN managed by the measurement information aggregation station 101. Thereafter, the measurement terminal 102 is data that is sensor measurement information in accordance with the CSMA (Carrier Sense Multiple Access) method defined by IEEE 802.15.4. 205 is transmitted to the measurement information aggregation station 101.

  The measurement information aggregating station 101 performs reception processing 207 based on the MCS information 206 notified together with the data 205, and notifies the measurement terminal 102 of success or failure of reception as ACK / NACK information 208. In response to this, the measurement terminal 102 performs transmission path quality information update processing 209 in AMC, and performs MCS update processing 210 based on the updated transmission path quality information. Here, for example, a packet error rate is used as the transmission path quality information.

  FIG. 3 shows an operation sequence of the AMC method in which the receiving side specifies MCS information. 2 differs from FIG. 2 in that the measurement information aggregation station 101 notifies the MCS information 301 in advance, and the measurement terminal 102 transmits data 205 according to the MCS information 301. The measurement information aggregating station 101 performs the reception process 302 of the data 205 based on the MCS information 301 specified by itself, notifies the measurement terminal 102 of the success or failure of reception as ACK / NACK information 208, and updates the quality information in the AMC. 303, and MCS update processing 304 is performed based on the updated quality information. Here, for example, a packet error rate or SINR based on reception success or failure is used as the quality information.

  FIG. 4 shows an operation sequence of the AMC method in which MCS information is not exchanged. 2 is different from FIG. 2 in that the notification of the MCS information 206 in FIG. 2 disappears and the measurement information aggregation station 101 performs the reception process 401 for all the MCS information instead.

  FIG. 5 shows an operation sequence at the time of collecting measurement information of the remote monitoring system of the first embodiment. In this embodiment, a packet error rate is used as an example of common transmission path quality information that can be measured by the measurement information aggregation station 101 and the measurement terminal 102. After the measurement terminal 102 is added to the PAN by the subscription request 202 to the permission notification 204, the measurement information aggregation station 101 notifies the measurement terminal 102 of the initial setting 501 and the MCS transition condition 502 before transmitting the data 205. When the measurement terminal 102 succeeds in receiving these pieces of information and MCS transition becomes possible, the measurement terminal 102 notifies the measurement information aggregation station 101 of an acknowledgment notification 503. The initial setting 501 defines an initial state of control such as quality information used for transition of MCS, for example, an initial value of MCS and an initialization request for quality information.

  FIG. 6 shows an example of the MCS transition condition 502. For each candidate MCS, a threshold for quality information for increasing or decreasing the MCS is defined. In general, the lower the modulation order and the lower coding rate, the higher the packet arrival rate even in an environment with poor propagation path quality, while the ratio of information in transmission data, that is, the resource efficiency decreases, so the number is low. It is desirable to set the MCS so that the modulation scheme and coding rate become higher in order. For example, in the case of communication using MCS # 3 in this embodiment, when the packet error rate exceeds the first threshold value 601, the packet error rate is updated to MCS # 2 that is one step lower and falls below the second threshold value 602. In this case, it is updated to MCS # 4 which is one step higher. For simplification of explanation, in this embodiment, the total number of candidate MCSs is set to 4 and the transition is performed one step at a time. Migration may be possible.

  In the notification of the ACK / NACK information 208 from the transmission of the data 205, there is no notification of the MCS information 206, and the measurement information aggregating station 101 performs the reception process 504 based on the specific MCS updated based on the MCS transition condition 502 and the quality information. I do. Thereby, since the notification of the MCS information 206 is not required, the processing load of the measurement terminal 102 is low, and the number of MCSs that try the reception process is reduced, so that the processing load of the measurement information aggregation station 101 is reduced.

  The measurement information aggregating station 101 determines the error rate update processes 505 and 507 and the MCS update processes 506 and 508 based on the contents of the ACK / NACK information 208 based on the result of the reception process 504 by a specific MCS. I do. Since the MCS transition condition 502 is shared, the measurement information aggregation station 101 can follow the MCS transition of the measurement terminal 102.

  In general, since the MCS used for control information such as the ACK / NACK information 208 has an arrival rate equal to or higher than the MCS with the highest packet arrival rate for data communication, the MCSs of the measurement terminal 102 and the measurement information collection station 101 are The error rate of the ACK / NACK information 208 does not increase to the extent that it deviates. Further, the reception error of the ACK / NACK information 208 can be solved by the fourth or fifth embodiment.

  In addition, a situation (disappearance) in which the measurement information aggregation station 101 cannot recognize the transmission of the data 205 may occur due to a packet collision or a header reception error in CSMA. Is counted by the measurement information aggregating station 101, that is, it is limited to that in which the reception processing 504 is performed and the ACK / NACK information 208 is notified. Since the measurement terminal 102 can recognize the loss of the data 205 when there is no notification of the ACK / NACK information 208, the data 205 is lost by retransmitting the data 205 if there is no notification of the ACK / NACK information 208 for a certain period of time after transmission of the data 205. You may deal with.

  FIG. 7 shows an operation flowchart of the measurement terminal 102 in the first embodiment. In this embodiment, a retransmission process for the loss of the data 205 is included. The measurement terminal 102 starts a timer for determining the disappearance of the data at the same time as the data transmission 701 (702), performs a time-out determination 703 at regular time intervals, and executes the data transmission 701 again at time-out. At this time, the comparison operation 704 between the number of retransmissions and the upper limit value avoids infinite retransmissions. The execution period of the timeout determination 703 may be set to, for example, a time required to transmit one information symbol in wireless communication, for example, 25 ms in IEEE 802.15.4 40-bit / s BPSK.

  If it is not determined to be lost, the measurement terminal 102 performs reception determination 705 for ACK / NACK information. If it is determined to be reception, the measurement terminal 102 performs error rate update processing 706 and MCS update processing. Specifically, the updated error rate is compared with the first threshold 601 (707), and if it exceeds, the MCS is decreased (708). If it is lower, the error rate is further compared with the second threshold 602 (709), and if it is lower, MCS is increased (710). The error rate can be updated, for example, by calculating the ratio of the number of reception failures (NACK) to the number of transmission packets within a certain period from the current time, or by the forgetting average using the current error rate and ACK / NACK information. As long as the measurement terminal 102 and the measurement information collection station 101 are the same, the error rate may be updated by any method.

  FIG. 8 shows an operation flowchart of the measurement information aggregation station 101 in the first embodiment. When data reception is detected (801), reception processing is performed based on the MCS updated based on the MCS transition condition 502 and quality information (802), and the result is notified to the measurement terminal 102 as ACK / NACK information. (803). Data detection 801 can be realized, for example, by taking a correlation between a predetermined preamble sequence for synchronization and a received signal. Thereafter, an error rate update process 804 and an MCS update process are performed based on the result of the reception process 802. Specifically, the updated error rate is compared with the first threshold 601 (805), and if it exceeds, the MCS is decreased (806). If it is lower, the error rate is further compared with the second threshold 602 (807), and if it is lower, MCS is increased (808).

  The operation of the remote monitoring system according to the second embodiment will be described with reference to FIGS. In the second embodiment, in addition to the configuration of the first embodiment, the number of continuous errors in the packet is used as the transmission path quality information, and the MCS is reduced even when an error occurs continuously, thereby reducing the propagation path. Improve packet arrival rate when quality deteriorates sharply.

FIG. 9 shows an operation flowchart of the measurement terminal 102 in the second embodiment.
When the reception determination 705 of the ACK / NACK information is determined as reception, the error rate update processing 706 and the continuous error number update processing 901 are performed, and the updated continuous error number is compared with a third threshold (902) ) Is different from FIG. 7 in that the MCS is decreased when it exceeds. The third threshold may be notified of a value for each MCS, for example, in the MCS transition condition 502. FIG. 10 shows an operation flowchart of the measurement information aggregating station 101 in the second embodiment. Based on the result of the reception process 802, the error rate update process 804 and the continuous error number update process 1001 are performed, and the updated number of continuous errors is compared with a third threshold (1002). The difference is different from FIG. The third threshold may be generated by the measurement information collection station 101 or set from the monitoring center 103.

  The operation of the remote monitoring system according to the third embodiment will be described with reference to FIGS. In the third embodiment, in addition to the configuration of the first embodiment, the ability to follow the AMC with respect to fluctuations in the propagation path quality is improved by allowing the MCS to transition in a plurality of stages.

  FIG. 11 shows an operation sequence of the third embodiment. The measurement information aggregation station 101 notifies the measurement terminal 102 of the MCS change amount setting 1101 together with the initial setting 501 and the MCS transition condition 502. The MCS change amount setting 1101 includes, for example, whether the MCS change amount is fixed and information on the maximum change amount of the MCS. When the amount of change is fixed, the maximum amount of change indicates a single MCS change amount itself. Hereinafter, a case where the MCS change amount is variable will be described.

  The measurement information aggregating station 101 records quality information such as SINR in the reception process 504, collects reception success / failure and quality information, and notifies the measurement terminal 102 as extended ACK / NACK information 1102. The quality information to be notified may be, for example, the quantized SINR itself. For example, in the reception process, the current MCS has a SINR that is largely insufficient and fails, or “1” when the SINR is excessively good. In other cases, it may be set to “0”. Thereafter, the measurement information aggregation station 101 and the measurement terminal 102 determine the MCS fluctuation range from the results of the quality information update processes 1103 and 1104 in the MCS update processes 506 and 508. Specifically, when the quality information indicates that the SINR is large and insufficient, the decrease width of the MCS is increased, and conversely, when the SINR indicates that the SINR is excessively good, the increase width of the MCS is increased. In addition, the measurement information aggregation station 101 may update the maximum change amount of MCS based on, for example, quality information (1105), and notify the measurement terminal 102 of the update result 1106. The case where the amount of change in MCS is variable has been described above. However, if the amount of change is fixed, a series of processes for determining the fluctuation range according to the quality information may not be performed.

FIG. 12 shows an operation flowchart of the measurement terminal 102 in the third embodiment.
Extended ACK / NACK information is received (1201), and quality information is updated according to the contents (1202). As described above, when the SINR is large or good or “1” is notified when the SINR is large or bad, the quality information is, for example, “+1” for ACK and “−1” for NACK. Just do it. Thereby, the quality information indicates a difference (a value of −1 to +1, where 0 is not excessive or insufficient) with respect to the SINR targeted by the MCS. Thereafter, when the MCS is increased or decreased, the fluctuation range of the MCS is determined from the quality information. Specifically, when reducing the MCS, if the quality information is below a certain level, the MCS reduction width is increased according to the absolute value (1203), and when increasing the MCS, the quality information is If it is above a certain level, the increase width of MCS is increased according to the absolute value (1204). Further, the maximum value of the MCS change amount may be updated (1205). For example, the maximum width is increased or decreased according to the absolute value of the quality information.

FIG. 13 shows an operation flowchart of the measurement information aggregation station 101 in the third embodiment. Quality information is set based on the reception quality (for example, SINR) in the reception process 802 (1301), and is notified to the measurement terminal 102 as extended ACK / NACK information together with the success or failure of reception (1302). At the same time, the quality information is updated (1303), and the fluctuation range when increasing or decreasing the MCS is determined according to the value. Specifically, when reducing the MCS, if the quality information is below a certain level, the MCS reduction range is increased according to the absolute value (1304), and when increasing the MCS, the quality information is If it is above a certain level, the increase width of MCS is increased according to the absolute value (1305). The quality information is set and updated in the same manner as the measurement terminal 102. Also, the maximum value of MCS change amount is updated (13
06). For example, the maximum width is increased or decreased according to the absolute value of the quality information.

  The operation of the fourth embodiment will be described with reference to FIGS. In the fourth embodiment, in addition to the configuration of the first embodiment, an ACK / NACK reception error is obtained by temporarily increasing the number of MCSs to be subjected to reception processing according to the determination of the measurement information aggregation station 101. Thus, even if the error rate is deviated between the measurement terminal 102 and the measurement information aggregating station 101, the reception process is successful, and the error rate is periodically notified to eliminate the deviation.

  FIG. 14 shows an operation sequence of the fourth embodiment. The reception process 504 is the same as in the first embodiment in the sense that a part of the MCS is selected from all candidates and the reception process is performed, and the measurement information aggregation station 101 sends the measurement terminal 102 to the measurement terminal 102 at an arbitrary timing. The difference is that the error rate is notified (1401), and the measurement terminal 102 is updated to the value notified of the error rate (1402).

  FIG. 15 shows an operation flowchart of the measurement information aggregating station 101 in the fourth embodiment. When the reception of data is detected, the measurement information aggregating station 101 first determines the MCS that performs the reception process 802 (1501). In a normal state, if only the MCS updated based on the MCS transition condition 502 and the transmission path quality information is used, the operation is the same as that of the first embodiment. On the other hand, when an MCS shift may occur with the measurement terminal 102, for example, immediately after the MCS is changed, for example, the MCS shift may be performed by setting both the pre-change MCS and the post-change MCS as reception processing targets. You can receive even if there is. After that, for example, when a certain time has passed since the change of MCS, when the error rate due to the MCS after the change becomes constant, or the error rate due to the MCS after the change is more constant than the error rate due to the MCS before the change In the case where the above is improved, the MCS for performing the reception process may be reduced. In this case, the ACK / NACK information 1502 for the measurement terminal 102 is notified of successful reception if successfully received by any MCS. However, the error rate used for determining the change of MCS is the error rate of MCS after change. As a result, if any one of the measurement terminal 102 and the measurement information aggregation station 101 increases the MCS and a deviation occurs, the error rate increases, and the original MCS is easily returned. Even if a deviation occurs due to the decrease in MCS, the system does not become unstable because it finally matches with the lowest MCS. In combination with the second embodiment, the error rate and MCS may be notified when the number of consecutive errors is a certain value or more.

  The operation of the fifth embodiment will be described with reference to FIG. In the fifth embodiment, in addition to the configuration of the first embodiment, an ACK / NACK reception error is obtained by temporarily increasing the number of MCSs to be subjected to reception processing based on the determination of the measurement information aggregation station 101. As a result, the success rate of the reception process in a situation where the error rate is shifted between the measurement terminal 102 and the measurement information aggregation station 101 is improved.

  FIG. 16 shows an operation flowchart of the measurement information aggregating station 101 in the fifth embodiment. It is determined whether or not the result of the reception processing 802 is an error (1601). If the result is an error, the reception processing is performed for the MCS that is further increased or decreased by one step from the MCS subjected to the reception processing (1602). It is determined whether or not the reception is successful at any MCS (1603). If the reception is successful, it is determined that the measurement terminal 102 is using a different MCS by one step, and the MCS used for the reception process is determined as a successful MCS. (1604). Thereby, even if there is a difference in MCS used by the measurement terminal 102 and the measurement information aggregation station 101, it can be resolved within one stage. In combination with the second embodiment, the error determination process 1601 may be a process of comparing the number of consecutive errors with a threshold value. As a result, it is possible to reduce reception processing with a plurality of MCSs for a random error in a situation where the MCSs match.

An example of functional configurations and apparatus configurations of the measurement terminal and the measurement information aggregation station in each of the above-described embodiments will be described with reference to FIGS.
FIG. 17 shows an example of a functional block diagram of the measurement information aggregation station 101 in each embodiment. The measurement information aggregating station 101 includes an antenna 1701, a wireless transmission / reception unit 1702, a control unit 1703, a baseband demodulation unit 1704, a decoding unit 1705, a network interface unit 1706, an encoding unit 1707, and a baseband modulation unit 1708.

  The wireless transmission / reception unit 1702 includes a duplexer, a power amplifier, a low noise amplifier, an up converter, a down converter, an analog / digital converter, a digital / analog converter, an automatic frequency adjuster, and an automatic gain adjuster. A radio frequency signal input from the antenna 1701 is converted into a baseband signal through the wireless transmission / reception unit 1702 and input to the baseband demodulation unit 1704. The baseband demodulator 1704 demodulates the input signal based on the MCS information given from the controller 1703 and inputs the result to the decoder 1705. The demodulation result is either a hard decision result (bit sequence) or a soft decision result (likelihood information) depending on the code used in the decoding unit 1705. The decoding unit 1705 performs error correction processing based on the MCS information given from the control unit 1703, and outputs the decoded data to the network interface unit 1706 and the control information and the decoding result to the control unit 1703. The network interface unit 1706 outputs the output of the decoding unit 1705 to the monitoring center 103 via the network 104, and when receiving control information from the monitoring center 103, inputs the information to the encoding unit 1707.

  Transmission data to the measurement terminal 102 input from the network interface unit 1706 or generated inside the measurement information aggregation station 101 is first input to the encoding unit 1707. The encoding unit 1707 encodes an input based on the MCS information given from the control unit 1703 and inputs the input to the baseband modulation unit 1708. A baseband signal modulated by baseband modulation section 1708 based on MCS information given from control section 1703 is input to radio transmission / reception section 1702, converted to a radio frequency signal, and output from antenna 1701.

  The control unit 1703 is a main component of the operation of the measurement information aggregation station 101 in each embodiment. The MCS transition condition table shown in FIG. 6, the current MCS value, and the error rate in the current MCS are managed, and the error rate is updated based on the decoding result information given from the decoding unit 1705, and further updated. The MCS is updated based on the error rate. In the data reception process, the baseband demodulation section 1704 and the decoding section 1705 are notified of MCS information. In addition, as a coordinator in IEEE 802.15.4, it manages the information of the measurement terminal 102 belonging to the PAN managed by itself, and the MCS transition condition table 502 for the measurement terminal 102 newly participating in the PAN. It has a function of sending initial setting information 501. In the second embodiment, the continuous error count is further managed, the continuous error count is updated based on the decoding result information provided from the decoding unit 1705, and the MCS is further updated based on the result. In the third embodiment, the propagation path quality information is also managed, the quality information given from the decoding unit 1705 is averaged, and the fluctuation range of the MCS is determined based on the result. In the fourth embodiment, a plurality of MCSs that perform reception processing are input to the baseband demodulation unit 1704 and the decoding unit 1705 according to the transition state of the MCS. Also, error rate information is input to the encoding unit 1707 at an arbitrary timing. In the fifth embodiment, an MCS that performs reception processing is additionally input to the baseband demodulation unit 1704 and the decoding unit 1705 based on the decoding result information provided from the decoding unit 1705.

  FIG. 18 shows an example of the apparatus configuration of the measurement information aggregation station 101 in each embodiment. The measurement information aggregation station 101 includes a processor 1801, a data buffer 1802, and a memory 1803, which are connected by an internal bus 1804. Further, a wireless transmission / reception unit 1702 and a network interface unit 1706 are provided as interfaces to the external node. Further, the measurement information aggregation station 101 includes a storage device 1805 that stores programs and tables.

  The processor 1801 executes a program stored in the storage device 1805. That is, the processor 1801 is a processing unit that executes a program, executes processing corresponding to the control unit 1703, etc., refers to a table, and controls wireless communication.

  The data buffer 1802 temporarily transmits an uplink signal received from the measurement terminal 102 or a downlink signal received from the monitoring center 103 or generated by the measurement information aggregation station 101 to the monitoring center 103 or the measurement terminal 102. Store. In the memory 1803, a program processed by the processor 1801 is expanded and data necessary for processing is held.

  The wireless transmission / reception unit 1702 and the network interface unit 1706 are interfaces that perform transmission / reception of wireless signals to / from the measurement terminal 102 and transmission / reception of signals to / from the monitoring center 103, as in FIG.

  The storage device 1805 stores a communication control program 1806, an MCS update program 1807, an MCS transition condition table 1808, a parameter management table 1809, and a PAN management table 1810. Note that programs and information corresponding to processing in the measurement information aggregating station 101 disclosed in this specification are also stored that are not shown.

  The communication control program 1806 and the MCS update program 1807 correspond to the control unit 1703 in FIG. The communication control program 1806 outputs the MCS information to the baseband demodulation unit 1704 and the decoding unit 1705 based on the function of updating the PAN management table in response to the PAN subscription request from the measurement terminal 102 and the parameter management table 1809. It has a function. In the fourth embodiment, the number of MCS information output to the baseband demodulation unit 1704 and the decoding unit 1705 is controlled based on the output of the MCS update program 1807. In the fifth embodiment, MCS information is additionally output to the baseband demodulation unit 1704 and the decoding unit 1705 based on the decoding result given from the decoding unit 1705.

  In the first embodiment, the MCS update program 1807 is based on the MCS information and error rate information stored in the parameter management table 1809, the decoding result given from the decoding unit 1705, and the MCS transition condition table 1808. Update error rate and MCS information. When the communication control program 1806 updates the PAN management table, the MCS transition condition table 1808 and initial setting information are notified to the newly participating measurement terminal 102, and at the same time, the parameters for the terminal are set in the parameter management table 1809. Generate. When the MCS transition condition table 1808 is given from the monitoring center 103, the setting operation and the update operation of the MCS transition condition table 1808 are included. In the second embodiment, the number of consecutive errors stored in the parameter management table 1809 is further updated based on the decoding result given from the decoding unit 1705, and the MCS is updated based on the result. In the third embodiment, the average quality information stored in the parameter management table is further updated based on the quality information given from the decoding unit 1705, and the fluctuation range in updating the MCS is determined based on the updated quality information. In the fourth embodiment, the error rate information stored in the parameter management table 1809 is output to the encoding unit 1707 at an arbitrary timing.

  The MCS transition condition table 1808 manages a list of MCS that can be selected in AMC and a threshold value of transmission path quality information for increasing or decreasing MCS when performing communication using each MCS. As the transmission path quality information, an error rate is used in the first embodiment, and a continuous error count is further used in the second embodiment.

  The parameter management table 1809 manages the currently used MCS and its error rate for each of the measurement terminals 102 participating in the PAN. In the second embodiment, the number of continuous errors is further managed, and in the third embodiment, quality information is further managed.

  The PAN management table 1810 manages information such as the physical ID of each measurement terminal 102 participating in the PAN.

  FIG. 19 shows an example of a functional block diagram of the measurement terminal 102 in each embodiment. The measurement terminal 102 includes an antenna 1901, a wireless transmission / reception unit 1902, a control unit 1903, a baseband demodulation unit 1904, a decoding unit 1905, an application interface unit 1906, an encoding unit 1907, and a baseband modulation unit 1908.

  The wireless transmission / reception unit 1902 includes a duplexer, a power amplifier, a low noise amplifier, an up converter, a down converter, an analog / digital converter, a digital / analog converter, an automatic frequency adjuster, and an automatic gain adjuster. A radio frequency signal input from the antenna 1901 is converted into a baseband signal through the wireless transmission / reception unit 1902 and input to the baseband demodulation unit 1904. Baseband demodulation section 1904 demodulates the input signal based on MCS information given from control section 1903 and inputs the result to decoding section 1905. The demodulation result is either a hard decision result (bit sequence) or a soft decision result (likelihood information) depending on the code used in the decoding unit 1905. The decoding unit 1905 performs error correction processing based on the MCS information given from the control unit 1903, and outputs the decoded data to the application interface unit 1906 and the control information and the decoding result to the control unit 1903. The application interface unit 1906 outputs the received data to the application, and outputs sensor measurement information input from the application to the encoding unit 1907.

  The sensor measurement information input from the application interface unit 1906 is first input to the encoding unit 1907. The encoding unit 1907 encodes the input based on the MCS information given from the control unit 1903 and inputs the input to the baseband modulation unit 1908. The baseband signal modulated by the baseband modulation unit 1908 based on the MCS information given from the control unit 1903 is input to the radio transmission / reception unit 1902, converted into a radio frequency signal, and output from the antenna 1901.

  The control unit 1903 is a main component of the operation of the measurement terminal 102 in each embodiment. The MCS transition condition table shown in FIG. 6, the current MCS value, and the error rate in the current MCS are managed, and the error rate is updated based on control information (ACK / NACK information 208) given from the decoding unit 1905. Then, the MCS is updated based on the updated error rate. In addition, MCS information is notified to encoding section 1907 and baseband modulation section 1908 during data transmission processing. Further, the MCS transition condition table 502 and the initial setting information notified from the measurement information aggregation station at the time of the subscription are notified to the measurement information aggregation station 101 as a router or endpoint in IEEE 802.15.4. 501 is stored inside. In the second embodiment, the continuous error count is further managed, the continuous error count is updated based on the control information (ACK / NACK information 208) given from the decoding unit 1905, and the MCS is further updated based on the result. To do. In the third embodiment, the propagation path quality information is also managed, the quality information included in the control information (extended ACK / NACK information 1102) given from the decoding unit 1705 is averaged, and the MCS fluctuation is based on the result. Determine the width.

  FIG. 20 shows an example of the device configuration of the measurement terminal 102 in the first embodiment. The measurement terminal 102 includes a processor 2001, a data buffer 2002, and a memory 2003, and each is connected via an internal bus 2004. Further, a wireless transmission / reception unit 1902 is provided as an interface to the external node. The measurement terminal 102 includes a storage device 2005 that stores programs and tables.

  The processor 2001 executes a program stored in the storage device 2005. That is, the processor 2001 is a processing unit that executes a program, executes processing corresponding to the control unit 1903, etc., refers to a table, and controls wireless communication.

  The data buffer 2002 temporarily stores the downlink signal received from the measurement information aggregation station 101 or the uplink signal input from the application for transmission to the application or measurement information aggregation station 101. In the memory 2003, a program processed by the processor 2001 is expanded and data necessary for the processing is held.

  The wireless transmission / reception unit 1902 is an interface that performs transmission / reception of wireless signals to / from the measurement information aggregation station 101, as in FIG.

  The storage device 2005 stores a communication control program 2006, an MCS update program 2007, an MCS transition condition table 2008, and a parameter management table 2009. Note that programs and information corresponding to processing in the measurement terminal 102 disclosed in the present specification are also stored that are not shown.

  The communication control program 2006 and the MCS update program 2007 correspond to the control unit 1903 in FIG. The communication control program 2006 notifies the encoding unit 1907 and the baseband modulation unit 1908 of MCS information based on the parameter management table 2009.

  In the first embodiment, the MCS update program 2007 is based on MCS information and error rate information stored in the parameter management table, and control information (ACK / NACK information 208) given from the decoding unit 1905. The MCS is updated based on the MCS transition condition table 2008. Further, when newly joining the PAN, the MCS transition condition table 2008 notified from the measurement information aggregation station 101 is stored, and the initial value and error count of the MCS are set based on the initial setting information notified simultaneously. In the second embodiment, the number of consecutive errors stored in the parameter management table 2009 is updated based on the control information (ACK / NACK information 208) given from the decoding unit 1905, and the MCS is updated based on the updated control information. Update. In the third embodiment, the average quality information stored in the parameter management table is further updated based on the quality information included in the control information (extended ACK / NACK information 1102) given from the decoding unit 1705, Based on the above, the fluctuation range in MCS update is determined.

  The MCS transition condition table 2008 manages a list of MCS that can be selected in AMC and a threshold value of transmission path quality information for increasing or decreasing MCS when performing communication using each MCS. As the transmission path quality information, an error rate is used in the first embodiment, and a continuous error count is further used in the second embodiment.

  The parameter management table 2009 manages the MCS currently used by the measurement terminal 102 and its error rate. In the second embodiment, the number of continuous errors is further managed, and in the third embodiment, quality information is further managed.

  Note that the separation of the functions shown in the above embodiments is merely an example, and other configurations may be used as long as the same functions can be realized as the overall embodiments of the remote monitoring system, the measurement information aggregation station, and the router. . Further, the second to fourth embodiments can be used in combination because the changes from the first embodiment are independent of each other.

  That is, the present invention is not limited to the above-described embodiments, and includes various modifications. For example, the above-described embodiments have been described in detail in order to explain the present invention in an easy-to-understand manner, and are not necessarily limited to those having all the configurations described. Further, a part of the configuration of one embodiment can be replaced with the configuration of another embodiment, and the configuration of another embodiment can be added to the configuration of one embodiment. Further, it is possible to add, delete, and replace other configurations for a part of the configuration of each embodiment.

  Each of the above-described configurations, functions, processing units, processing means, and the like may be realized by hardware by designing a part or all of them with, for example, an integrated circuit. In addition, each of the above-described configurations, functions, and the like has been mainly described in the case where they are realized by software by executing programs that realize the respective functions. However, information such as programs, tables, and files that realize the respective functions is stored in the memory. In addition, it can be stored in a recording device such as a hard disk or SSD (Solid State Drive), or a recording medium such as an IC card, SD card, or DVD, and can be downloaded and installed via a network as necessary. It is also possible to do.

  The present invention is applicable to a remote monitoring system that monitors measurement information of sensors and the like at a monitoring center and a communication device that uses wireless communication.

101 Measurement Information Aggregation Station 102 Measurement Terminal 103 Monitoring Center 104 Network 105 Wireless Network 501 Initial Setting Information 502 MCS Transition Condition 503 Acknowledgment Notification 504 Uplink Data Reception Processing Based on Specified MCS 505, 507 Quality Information Update Processing 506, 508 MCS MCS update process based on transition condition and quality information 601 First threshold value for error rate for decreasing MCS 602 Second threshold value for error rate for increasing MCS 701 Data transmission process 702 Loss determination timer start process 703 Loss determination processing 704 Retransmission count determination processing 705 ACK / NACK information reception determination processing 706 Error rate update processing 707 Comparison processing between error rate and first threshold 708 MCS reduction processing 709 Comparison between error rate and second threshold Processing 710 MCS increase processing 801 Data reception determination processing 802 Data reception processing 803 ACK / NACK information transmission processing 804 Error rate update processing 805 Comparison processing between error rate and first threshold 806 MCS reduction processing 807 Error rate and second threshold 808 MCS increase processing 901 Continuous error number update processing 902 Comparison operation between continuous error number and third threshold 1001 Continuous error number update processing 1002 Comparison operation between continuous error number and third threshold 1101 Change in MCS Setting information about amount 1102 Composite information of ACK / NACK information and quality information 1103 Quality information update processing 1104 Quality information update processing 1105 Maximum MCS change amount update processing 1106 Maximum MCS change amount information 1201 ACK / NACK information and quality information reception determination processing 1202 quality Information update processing 1203 MCS decrease amount determination processing 1204 MCS increase amount determination processing 1205 Maximum MCS change amount update processing 1301 Quality information setting processing 1302 ACK / NACK information and quality information transmission processing 1303 Quality information update processing 1304 MCS decrease amount Decision processing 1305 MCS increase amount decision processing 1306 maximum MCS change amount update processing 1401 error rate information 1402 error rate update processing 1501 MCS decision processing 1501 that performs reception processing 1502 ACK / NACK decision and transmission processing 1601 error judgment of reception processing Processing 1602 One-step different MCS reception determination processing 1603 Successful reception determination processing 1604 MCS update processing 1701 Antenna 1702 Wireless transmission / reception unit 1703 Control unit 1704 Baseband demodulation unit 1705 Decoding unit 1706 Network interface unit 1707 encoding unit 1708 baseband modulation unit 1801 processor 1802 data buffer 1803 memory 1804 internal bus 1805 storage device 1806 communication control program 1807 MCS update program 1808 MCS transition condition table 1809 parameter management table 1810 PAN management table 1901 antenna 1902 Wireless transceiver 1903 Control unit 1904 Baseband demodulation unit 1905 Decoding unit 1906 Application interface unit 1907 Encoding unit 1908 Baseband modulation unit 2001 Processor 2002 Data buffer 2003 Memory 2004 Internal bus 2005 Storage device 2006 Communication control program 2007 MCS update program 2008 MCS Transition condition Table 2009 Parameter management table.

Claims (14)

An adaptive modulation and coding method in a system that performs wireless communication on a transmission side and a reception side,
Sharing the transition condition of the modulation and coding scheme using the quality information of the common channel that can be measured independently on the transmitting side and the receiving side as an index,
Based on the quality information measured independently on each of the transmission side and the reception side, and the shared transition condition, the transmission side and the reception side each switch the modulation and coding scheme,
The receiving side targets a part of the candidate modulation and coding schemes for reception processing,
During operation by the determination of the receiving side, temporarily increase the number of the modulation and coding schemes that are the target of the reception processing,
The condition for increasing the number of modulation and coding schemes to be subjected to the reception process is a period from when the modulation and coding scheme is switched until a predetermined number of packets are received in advance.
And an adaptive modulation and coding method. An adaptive modulation and coding method in a system that performs wireless communication on a transmission side and a reception side,
Sharing the transition condition of the modulation and coding scheme using the quality information of the common channel that can be measured independently on the transmitting side and the receiving side as an index,
Based on the quality information measured independently on each of the transmission side and the reception side, and the shared transition condition, the transmission side and the reception side each switch the modulation and coding scheme,
The receiving side targets a part of the candidate modulation and coding schemes for reception processing,
During operation by the determination of the receiving side, temporarily increase the number of the modulation and coding schemes that are the target of the reception processing,
The condition for increasing the number of modulation and coding schemes to be subjected to the reception process is a packet error when performing the reception process using the modulation and coding scheme after switching from switching the modulation and coding scheme The period until the rate falls below a predetermined threshold, or the period until the packet error rate falls below a predetermined value more than the packet error rate when performing the reception process using the modulation and coding scheme before switching. Is,
And an adaptive modulation and coding method. The adaptive modulation and coding method according to claim 1 or 2,
The quality information is a packet error rate of wireless communication or the number of continuous packet errors of wireless communication.
And an adaptive modulation and coding method. The adaptive modulation and coding method according to claim 1 or 2,
The transmission side and the reception side can share the current quality information using the shared transition condition.
And an adaptive modulation and coding method. The adaptive modulation and coding method according to claim 1 or 2,
In switching between the modulation and coding schemes on the transmission side and the reception side, the variation amount of the modulation and coding scheme is variable.
And an adaptive modulation and coding method. The adaptive modulation and coding method according to claim 1 or 2,
In switching between the modulation and coding schemes on the transmission side and the reception side, the amount of fluctuation of the modulation and coding scheme is changed to the quality information used for switching the modulation and coding scheme or other quality information other than that. Take multiple values determined based on,
And an adaptive modulation and coding method. An aggregation station device that performs wireless communication with a measurement terminal device,
A wireless transmission / reception unit using a modulation and coding system and a processing unit;
The processor is
Transition conditions of the modulation and coding scheme that are shared with the measurement terminal device and using the quality information of a common channel that can be measured independently by the aggregation station device and the measurement terminal device as an index, and independent by the aggregation station device Based on the quality information measured, the modulation and coding scheme is switched,
A part of the modulation and coding schemes that are candidates for reception processing,
The processor is
During operation, temporarily increase the number of modulation and coding schemes to be subjected to the reception process,
The condition for increasing the number of modulation and coding schemes to be subjected to the reception process is a period from when the modulation and coding scheme is switched until a predetermined number of packets are received in advance.
An aggregation station apparatus characterized by that. An aggregation station device that performs wireless communication with a measurement terminal device,
A wireless transmission / reception unit using a modulation and coding system and a processing unit;
The processor is
Transition conditions of the modulation and coding scheme that are shared with the measurement terminal device and using the quality information of a common channel that can be measured independently by the aggregation station device and the measurement terminal device as an index, and independent by the aggregation station device Based on the quality information measured, the modulation and coding scheme is switched,
A part of the modulation and coding schemes that are candidates for reception processing,
The processor is
During operation, temporarily increase the number of modulation and coding schemes to be subjected to the reception process,
The condition for increasing the number of modulation and coding schemes to be subjected to the reception process is a packet error when performing the reception process using the modulation and coding scheme after switching from switching the modulation and coding scheme The period until the rate falls below a predetermined threshold, or the period until the packet error rate falls below a predetermined value more than the packet error rate when performing the reception process using the modulation and coding scheme before switching. Is,
An aggregation station apparatus characterized by that. The aggregation station device according to claim 7 or 8,
The quality information is a packet error rate of wireless communication or the number of continuous packet errors of wireless communication.
An aggregation station apparatus characterized by that. The aggregation station device according to claim 7 or 8,
The processor is
Using the shared transition condition, the current quality information can be shared.
An aggregation station apparatus characterized by that. The aggregation station device according to claim 7 or 8,
The processor is
In switching between the modulation and coding schemes on the transmission side and the reception side, the variation amount of the modulation and coding scheme is variable.
An aggregation station apparatus characterized by that. The aggregation station device according to claim 7 or 8,
The processor is
In the switching of the modulation and coding scheme, a plurality of values in which the variation amount of the modulation and coding scheme is determined based on the quality information used for switching the modulation and coding scheme or the other quality information other than that Take
An aggregation station apparatus characterized by that. A measurement terminal device that performs wireless communication with an aggregation station device,
A wireless transmission / reception unit using a modulation and coding system and a processing unit;
The processor is
Transition of the modulation and coding scheme using, as an index, quality information of a common channel that is received from the aggregation station apparatus and shared with the aggregation station apparatus and can be measured independently by the measurement terminal apparatus and the aggregation station apparatus Under the terms and the quality information measured independently in the measuring terminal apparatus, it switches the modulation and coding scheme,
A part of the modulation and coding schemes that are candidates for reception processing,
During operation, temporarily increase the number of modulation and coding schemes to be subjected to the reception process,
The condition for increasing the number of modulation and coding schemes to be subjected to the reception process is a period from when the modulation and coding scheme is switched until a predetermined number of packets are received in advance.
A measuring terminal device. A measurement terminal device that performs wireless communication with an aggregation station device,
A wireless transmission / reception unit using a modulation and coding system and a processing unit;
The processor is
Transition of the modulation and coding scheme using, as an index, quality information of a common channel that is received from the aggregation station apparatus and shared with the aggregation station apparatus and can be measured independently by the measurement terminal apparatus and the aggregation station apparatus Under the terms and the quality information measured independently in the measuring terminal apparatus, it switches the modulation and coding scheme,
A part of the modulation and coding schemes that are candidates for reception processing,
During operation, temporarily increase the number of modulation and coding schemes to be subjected to the reception process,
The condition for increasing the number of modulation and coding schemes to be subjected to the reception process is a packet error when performing the reception process using the modulation and coding scheme after switching from switching the modulation and coding scheme The period until the rate falls below a predetermined threshold, or the period until the packet error rate falls below a predetermined value more than the packet error rate when performing the reception process using the modulation and coding scheme before switching. Is,
A measuring terminal device.

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