JP6566490B2 - Wireless slave unit, wireless slave unit control method and control program - Google Patents

Description

  The present invention relates to a wireless slave device, a wireless slave device control method, and a control program.

  In recent years, research and development for speeding up and increasing the capacity of mobile radio communication has been underway. Patent Document 1 includes a plurality of antennas and a plurality of systems of wireless circuits, and in a wireless terminal whose shape changes, when the shape of the wireless terminal is detected and the shape is a shape with good antenna characteristics, A technique is disclosed in which power is supplied to a plurality of wireless circuits to perform MIMO (multiple input / output) communication. In Patent Document 2, in a wireless communication system including a plurality of wireless stations and a central server, in an environment in which a change in radio field intensity occurs, a propagation path is estimated according to the change, and the wireless parameters of the wireless station are A technique for automatically reconfiguring a wireless communication path by automatically adjusting according to an estimation result and realizing a desired communication environment is disclosed. Patent Document 3 discloses a base station that includes a plurality of antennas and communicates with a plurality of terminal devices at the same time. In order to improve reception quality with each terminal device, channel state information between the terminal devices is described. A technique for acquiring, spreading and multiplexing a plurality of signals addressed to each terminal apparatus using a spreading code in the spatial direction of each terminal apparatus, and precoding the spread and multiplexed signal based on channel state information is disclosed. .

JP 2010-004243 A JP 2010-147519 A International Publication No. 2015/0887716

  In recent years, since many wireless terminals (wireless slaves) having a plurality of antennas have been released, there are innumerable combinations of antenna orientations of wireless terminals and wireless routers (wireless masters). For this reason, the direction of the antenna connected to the wireless terminal may not be the direction with the highest communication speed (for example, the direction with the highest S / N ratio). In such a case, there is a problem that the communication speed inherent to the wireless terminal cannot be exhibited in communication with the wireless router. On the other hand, Patent Documents 1 to 3 described above do not describe any means for optimizing the orientation of the antenna of the wireless terminal in order to exhibit the original communication speed of the wireless terminal in communication with the wireless router.

  The present invention has been made in view of the above background, and provides a wireless slave device capable of optimizing an antenna direction and substantially maximizing a communication speed in communication with a wireless master device. Objective.

  The present invention is configured so that the orientation can be changed, and an antenna that communicates with a radio base unit, a movable portion that rotates the antenna, and the orientation of the antenna is adjusted by controlling the movable portion. And a measurement unit that measures RSSI and noise in communication with the wireless master device, wherein the measurement unit changes an antenna angle that defines the direction of the antenna in predetermined rotation angle increments, and The RSSI and noise are measured at each antenna angle in increments of rotation angles, the S / N ratio is calculated from the RSSI and noise measurement results at each antenna angle, and the direction of the antenna is calculated from the S / N calculated from the measurement results. Adjustment is made so that the antenna angle corresponding to the highest ratio is obtained.

  Further, the present invention is a method for controlling a wireless slave device comprising an antenna configured to be capable of changing a direction and performing communication with a wireless master device, and a movable part that rotates the antenna. The step of measuring the RSSI and noise at each antenna angle in the predetermined rotation angle increments by changing the antenna angle that defines the direction of the antenna at a predetermined rotation angle increment, and the measurement results of RSSI and noise at each antenna angle Calculating an S / N ratio, and adjusting the antenna direction so that the antenna angle corresponds to the highest one of the S / N ratios calculated from the measurement results.

  Furthermore, the present invention is a control program for controlling a wireless slave device including an antenna configured to change the orientation and performing communication with the wireless master device, and a movable unit that rotates the antenna. , A process of changing the antenna angle defining the direction of the antenna at predetermined rotation angle increments, and measuring RSSI and noise at each antenna angle of the predetermined rotation angle increment, and measuring RSSI and noise at each antenna angle Calculating an S / N ratio from the result, and causing the computer to execute processing for adjusting the antenna direction so that the antenna angle corresponding to the highest S / N ratio calculated from the measurement result is obtained. Is.

  According to the present invention, it is possible to optimize the antenna direction and to substantially maximize the communication speed in communication with the wireless master device.

It is a figure explaining the outline | summary of this invention. 1 is a block diagram illustrating a schematic configuration of a wireless slave device according to a first embodiment; 4 is a flowchart showing a flow of processing for clarifying a maximum movable range of an antenna in the wireless slave device according to the first exemplary embodiment; 6 is a flowchart showing a flow of processing for determining the direction of an antenna in which the S / N ratio is relatively high in the measurement unit of the wireless slave device according to the first exemplary embodiment; It is a table | surface which shows an example of the measurement result of RSSI, noise, and power consumption with respect to the antenna angle n memorize | stored in the storage medium after the processing flow of FIG. 6 is a flowchart showing a flow of processing for adjusting the antenna direction to a direction in which the S / N ratio is substantially maximized in the measurement unit of the wireless slave device according to the first exemplary embodiment; It is a table | surface which shows the measurement result of RSSI, noise, and power consumption with respect to the antenna angle n measured by the processing flow of FIG. 6, and memorize | stored in the storage medium. FIG. 7 is a flowchart showing a flow of processing for determining an optimum antenna angle V by comparing throughputs when a measurement result obtained by the processing flow of FIG. 6 includes RSSI> −30 dBm. FIG. 7 is a flowchart showing a flow of processing for determining an optimum antenna angle V by comparing throughputs when a measurement result obtained by the processing flow of FIG. 6 includes RSSI> −30 dBm. It is a table | surface which shows an example of the result of having extracted the thing with the highest S / N ratio, and the RSSI larger than -30dBm from the table | surface shown in FIG. 9 is a flowchart showing a flow of processing for controlling transmission power after optimizing an antenna direction in a measurement unit of a wireless slave device according to a second exemplary embodiment; 9 is a flowchart showing a flow of processing for controlling transmission power after optimizing an antenna direction in a measurement unit of a wireless slave device according to a second exemplary embodiment; In the measurement unit of the wireless slave device according to the second embodiment, the process flow when performing the process of detecting the antenna direction in which the S / N ratio is substantially maximized within the maximum movable range of the antenna in one step is as follows. It is a flowchart to show.

[Features of the present invention]
Prior to the description of the embodiments of the present invention, an outline of the features of the present invention will be described first.

  FIG. 1 is a diagram for explaining the outline of the present invention. As shown in FIG. 1, the wireless slave device 1 includes an antenna 3, a movable unit 4, and a measurement unit 7. The antenna 3 is configured so that the orientation can be changed, and performs communication with the wireless master device 21. The movable part 4 rotates the antenna 3. The measurement unit 7 controls the movable unit 4 to adjust the direction of the antenna 3 and measures RSSI and noise in communication with the wireless master device 21.

  The measurement unit 7 changes the antenna angle that defines the direction of the antenna in predetermined rotation angle increments, and measures RSSI (Received Signal Strength Indicator) and noise at each antenna angle in the predetermined rotation angle increments. Then, the S / N ratio (Signal to Noise Ratio) is calculated from the measurement results of RSSI and noise at each antenna angle, and the direction of the antenna corresponds to the highest S / N ratio calculated from the measurement results. Adjust the antenna angle.

  Thereby, in the communication with the wireless master device, the direction of the antenna can be optimized well in order to substantially maximize the communication speed.

[Embodiment 1]
Embodiment 1 of the present invention will be described below with reference to the drawings.
First, a schematic configuration of the wireless slave device 101 according to the first embodiment will be described. FIG. 2 is a block diagram of a schematic configuration of the wireless slave device 101 according to the first embodiment. As shown in FIG. 2, the wireless slave device 101 communicates with a wireless router (wireless master device) 121 having a wireless I / F 122.

  The wireless slave device 101 includes a wireless slave device main body 102, an antenna 103, a movable unit 104, and a wattmeter 108. The wireless slave device main body 102 includes a wireless I / F 105 and a movable I / F 106. The wireless I / F 105 is for modulating / demodulating radio waves transmitted / received via the antenna 103. In the wireless slave device 101, a signal transmitted from the wireless I / F 122 of the wireless router 121 is received by the antenna 103 and demodulated by the wireless I / F 105. The transmission signal modulated by the wireless I / F 105 is transmitted from the antenna 103 to the wireless I / F 122 of the wireless router 121.

  The movable part 104 is a drive mechanism for operating (rotating) the antenna 103 within the maximum movable range. The movable I / F 106 controls the operation of the antenna 103 by the movable unit 104. The measurement unit 107 measures RSSI and noise in communication with the wireless router 121 and calculates an S / N ratio. Here, the S / N ratio is a value obtained by subtracting noise from RSSI (S / N ratio = RSSI−noise). The wattmeter 108 is for measuring the power consumption of the wireless slave device 101 in response to an instruction from the measurement unit 107, and is connected to the wireless slave device body 102. The wattmeter 108 may be connected to the external power source 110. The storage medium 109 stores the measured RSSI, noise, and power consumption corresponding to the antenna angle.

Next, a flow of processing for clarifying the maximum movable range of the antenna 103 in the measurement unit 107 will be described.
FIG. 3 is a flowchart showing a flow of processing for clarifying the maximum movable range of the antenna 103 in the measurement unit 107. As shown in FIG. 3, first, the antenna 103 is operated in the minus rotation direction (counterclockwise) (step S101). Subsequently, it is determined whether or not the rotational movement of the antenna 103 is stopped (step S102). If it is determined in step S102 that the rotational movement of the antenna 103 has stopped, it can be determined that the position of the antenna 103 has reached the limit in the minus rotation direction (minus limit), so the operation of the antenna 103 is stopped (step S103). ).

  Subsequent to step S103, the antenna 103 is operated in the positive rotation direction (clockwise) (step S104). Subsequently, it is determined whether or not the rotational movement of the antenna 103 is stopped (step S105). If it is determined in step S105 that the rotational movement of the antenna 103 has stopped, it can be determined that the position of the antenna 103 has reached the limit in the positive rotation direction (plus limit), so the operation of the antenna 103 is stopped (step S106). ). Subsequently, the angle at which the antenna 103 is rotated from the minus limit to the plus limit is stored in the storage medium 109 as the maximum movable range (step 107).

  Next, a process of extracting the antenna angle at which the S / N ratio is substantially maximized within the maximum movable range of the antenna 103 in the measurement unit 107 and adjusting the direction of the antenna 103 to be the antenna angle. Will be described below. In the following description, the configuration of the wireless slave device 101 is appropriately referred to FIG.

  The measurement unit 107 operates the antenna 103 at predetermined rotation angle increments to measure the RSSI, noise, and power consumption in order to extract the direction of the antenna 103 that substantially maximizes the S / N ratio. In detecting the orientation of the antenna 103 at which the S / N ratio is substantially maximized, first, RSSI, noise, and power consumption are measured at a relatively coarse predetermined rotation angle (first rotation angle Δθ1). Estimate the orientation of the antenna where the / N ratio is relatively high. The first rotation angle Δθ1 is, for example, 30 °.

  FIG. 4 is a flowchart showing a flow of processing in the measurement unit 107 to determine the direction of the antenna where the S / N ratio is relatively high. As shown in FIG. 4, first, the antenna 103 is moved to the minus limit of the maximum movable range (step S201). Then, the antenna angle n is set to zero (n = 0) (step S202). Subsequently, RSSI, noise, and power consumption are measured (step S203). The measured RSSI, noise, and power consumption measurement results are stored in the storage medium 109 in association with the antenna angle n (step S204).

  Following step S204, it is determined whether or not the antenna angle n is equal to the plus limit of the maximum movable range (step S205). When it is determined in step S205 that the antenna angle n is not equal to the plus limit of the maximum movable range (NO), the antenna 103 is rotated in the plus rotation direction by the first rotation angle Δθ1 (step S206). Then, the first rotation angle Δθ1 is added to the antenna angle n (n = n + Δθ1) to update the antenna angle n (step S207), and then the process returns to step S203. On the other hand, when it is determined in step S205 that the antenna angle n is equal to the plus limit of the maximum movable range (in the case of YES), the antenna angle having the highest S / N ratio among the measurement results is set as the provisional optimal antenna angle m. Extract (step S208).

  FIG. 5 is a table showing an example of measurement results of RSSI, noise, and power consumption with respect to the antenna angle n stored in the storage medium 109 after the processing flow of FIG. Here, the first rotation angle Δθ1 is 30 °. As shown in FIG. 5, the measurement results of RSSI, noise, and power consumption are stored in increments of 30 ° from 0 ° to 330 ° of the antenna angle n. Among the measurement results, the antenna angle n with the highest S / N ratio is extracted as the provisional optimum antenna angle m.

  Next, within a predetermined range (neighboring range) in the vicinity of the provisional optimum antenna angle m extracted by the processing flow of FIG. 4, RSSI in increments of a minute rotation angle (second rotation angle Δθ2) smaller than the first rotation angle Δθ1. Noise and power consumption measurements are taken to find the antenna orientation where the S / N ratio is substantially maximized. The second rotation angle Δθ2 is 1 °, for example. Further, the angle range in the vicinity of the provisional optimum antenna angle m is, for example, a range of m− (Δθ1−Δθ2) ≦ m ≦ m + (Δθ1−Δθ2). That is, in the vicinity range of the temporary optimal antenna angle m, the plus limit is m + (Δθ1−Δθ2), and the minus limit is m− (Δθ1−Δθ2).

  FIG. 6 is a flowchart showing a flow of processing in the measurement unit 107 for adjusting the direction of the antenna 103 so that the S / N ratio is substantially maximized. As shown in FIG. 6, first, the antenna 103 is moved to the plus limit (m + (Δθ1−Δθ2)) in the vicinity of the temporary optimum antenna angle m (step S301). Subsequently, the initial value of the antenna angle n is set to a plus limit (m + (Δθ1−Δθ2)) in the vicinity of the temporary optimal antenna angle m (step S302). Subsequently, RSSI, noise, and power consumption are measured (step S303). The measured RSSI, noise, and power consumption are stored in the storage medium 109 as measurement results at the current antenna angle n (step S304).

  Following step S304, it is determined whether or not the antenna angle n is equal to the minus limit (m− (Δθ1−Δθ2)) in the vicinity of the temporary optimal antenna angle m (step S305). In step S305, when it is determined that the antenna angle n is not equal to the negative limit (m− (Δθ1−Δθ2)) in the vicinity of the temporary optimal antenna angle m (in the case of NO), the antenna 103 is moved in the negative rotation direction. It is rotated by the second rotation angle Δθ2 (step S306). Then, the second angle Δθ2 is subtracted from the antenna angle n (n = n−Δθ2) (step S307), and the process returns to step S303. On the other hand, when it is determined in step S305 that the antenna angle n is equal to the minus limit (m− (Δθ1−Δθ2)) in the vicinity range of the temporary optimal antenna angle m (in the case of YES), among the measurement results, S The antenna angle with the highest / N ratio is extracted as the optimum antenna angle V (step S308). Then, the orientation of the antenna 103 is adjusted so that the orientation of the antenna 103 becomes the optimum antenna angle V (step S309).

  FIG. 7 is a table showing measurement results of RSSI, noise, and power consumption with respect to the antenna angle n, which are measured by the processing flow of FIG. 6 and stored in the storage medium 109. Here, the second rotation angle Δθ2 is set to 1 °. As shown in FIG. 7, measurement results of RSSI, noise, and power consumption are stored in increments of 1 ° from an antenna angle n of {m− (Δθ1−Δθ2)} ° to {m + (Δθ1−Δθ2)} °. . Among the measurement results, the antenna angle n having the highest S / N ratio is extracted as the optimum antenna angle V.

  In the measurement result obtained by the processing flow shown in FIG. 6, when the RSSI is greater than −30 dBm (RSSI> −30 dBm), the process of step S <b> 308 in FIG. The optimum antenna angle V may be extracted by measuring the throughput and comparing the measurement results of the throughput. This is because if the RSSI is greater than −30 dBm, the S / N ratio may not be proportional to the communication speed, and even if the S / N ratio is maximum, the communication speed may not be maximum.

  8 and 9 determine the optimum antenna angle V by comparing the throughput when the measurement result obtained by the processing flow of FIG. 6 in the measurement unit 107 includes RSSI> −30 dBm. It is a flowchart which shows the flow of a process. As shown in FIG. 8, first, an antenna angle is extracted from the measurement result obtained by the processing flow shown in FIG. 6 (RSSI> -30 dBm) (RSSI> -30 dBm) (step S401). Then, the antenna 103 is moved so that the direction of the antenna 103 becomes the smallest among the antenna angles extracted in step S401 (step S402).

  Subsequently, the antenna angle n is set to the current antenna angle (step S403). Subsequently, the throughput is measured (step S404). Then, the throughput measurement result is stored in the storage medium 109 in association with the antenna angle n (step S405). Subsequently, it is determined whether or not there is an antenna angle extracted in step S401 larger than the antenna angle n (step S406).

  In step S406, when it is determined that there is an antenna angle extracted in step S401 that is larger than the antenna angle n (in the case of YES), the antenna angle among the antenna angles that are larger than the antenna angle n is determined. The antenna 103 is moved so that the antenna angle closest to n is obtained (step S407), and the process returns to step S403. In Step S406, when it is determined that none of the antenna angles extracted in Step S401 is larger than the antenna angle n (in the case of NO), the antenna angle having the largest throughput among the antenna angles satisfying RSSI> −30 dBm is selected. Extract (step S408).

  Following step S408, as shown in FIG. 9, among the measurement results obtained by the processing flow shown in FIG. 6, the antenna having the highest S / N ratio among those having an RSSI of −30 dBm or less (RSSI ≦ −30 dBm). An angle is extracted (step S409). Then, the antenna 103 is moved so that the direction of the antenna 103 becomes the antenna angle extracted in step S409 (step S410). Subsequently, the antenna angle n is set to the current antenna angle (step S411).

  Subsequent to step S411, the throughput is measured (step S412). Then, the throughput measurement result is stored in the storage medium 109 in correspondence with the antenna angle n (step S413). Subsequently, it is determined whether the antenna angle throughput extracted in step S409 is larger than the antenna angle throughput extracted in step S408 (step S414).

  In step S414, when the throughput of the antenna angle extracted in step S409 is larger than the throughput of the antenna angle extracted in step S408 (in the case of YES), the antenna angle extracted in step S409 is set as the optimum antenna angle (step S414). S415). On the other hand, when the throughput of the antenna angle extracted in step S409 is not larger than the throughput of the antenna angle extracted in step S408 in step S414 (in the case of NO), the antenna angle extracted in step S408 is set as the optimum antenna angle. (Step S416).

  FIG. 10 is a table showing an example of a result obtained by extracting one having the highest S / N ratio and one having an RSSI larger than −30 dBm (RSSI> −30 dBm) from the table shown in FIG. 7. For example, in FIG. 7, the S / N ratio is maximum when the antenna angle n is m−28 °, and the RSSI is − when the antenna angle n is m−25 °, m−11 °, m + 14 °, and m + 22 °. It is assumed that it is larger than 30 dBm. In this case, as shown in FIG. 10, the measurement results of antenna angles n of m−28 °, m−25 °, m−11 °, m + 14 °, and m + 22 ° are extracted from FIG.

  Through the processing flow shown in FIG. 8, throughput is measured for antenna angles n of m−25 °, m−11 °, m + 14 °, and m + 22 °, respectively. Further, according to the processing flow shown in FIG. 9, the throughput is measured when the antenna angle n is m−28 °. The optimum antenna angle V is the one with the maximum throughput among the antenna angles.

  As described above, in the wireless slave device 101 according to the present embodiment, in order to optimize the antenna direction in the measurement unit 107, first, as a first step, as shown in the processing flow shown in FIG. The RSSI, noise, and power consumption are measured in increments of the first rotation angle Δθ1, which is the rotation angle, to determine the direction of the antenna in which the S / N ratio is relatively high. Then, as a second stage, as shown in the processing flow shown in FIG. 6, in the vicinity of the antenna orientation where the S / N ratio is relatively high, the RSSI is incremented by a second rotation angle Δθ2 smaller than the first rotation angle Δθ1. Then, noise and power consumption are measured to extract the direction of the antenna having the highest S / N ratio (optimum antenna angle). Thus, the extraction process of the antenna having the highest S / N ratio is performed in two stages as described above, whereby the detection process can be performed efficiently. Then, the orientation of the antenna 103 is adjusted so that the orientation of the antenna 103 becomes the extracted optimum antenna angle. In communication with the wireless master device, the communication speed is generally proportional to the S / N ratio, except when the RSSI is too strong. That is, the higher the S / N ratio, the faster the communication speed. Therefore, the communication speed can be maximized by adjusting the direction of the antenna so that the S / N ratio is substantially maximized. Therefore, according to the present embodiment, the direction of the antenna can be optimized and the communication speed can be substantially maximized in communication with the wireless router.

  Further, when the RSSI is greater than −30 dBm, the throughput at the antenna angle having the highest S / N ratio and the throughput at the antenna angle at which the RSSI is greater than −30 dBm are measured. Then, the antenna angle corresponding to the largest measured throughput is extracted as the optimum antenna angle. In this way, the direction of the antenna can be better optimized in order to substantially maximize the communication speed in communication with the wireless router.

[Embodiment 2]
The second embodiment of the present invention will be described below with reference to the drawings. In addition, about the part which is common in Embodiment 1, the same code | symbol is attached | subjected and the description is abbreviate | omitted.
The schematic configuration of the wireless slave device according to the second embodiment is the same as the schematic configuration of the wireless slave device 101 shown in FIG. Further, the processing for clarifying the maximum movable range of the antenna 103 in the measurement unit 107 of the wireless slave device 101 is the same as the processing described with reference to FIG. 3 in the first embodiment. The measurement unit 107 performs processing for extracting the antenna angle at which the S / N ratio is substantially maximized within the maximum movable range of the antenna 103 and adjusting the direction of the antenna 103 to be the antenna angle. In the first embodiment, the processing is the same as that described with reference to FIGS. 4, 6, 8, and 9. In this embodiment, after the direction of the antenna 103 is optimized in the measurement unit 107, the transmission power is further controlled. This point is different from the first embodiment.

  FIG. 11 and FIG. 12 are flowcharts showing the flow of processing for controlling transmission power after optimizing the direction of the antenna 103 in the measurement unit 107. As shown in FIGS. 11 and 12, first, the antenna 103 is moved so that the orientation of the antenna 103 becomes the optimum antenna angle obtained by the processing flow shown in FIG. 9 (step S501). Subsequently, the RSSI is measured, and the RSSI obtained by the measurement is stored in the storage medium 109 as the pre-adjustment RSSIb (step S502). It is determined whether the pre-adjustment RSSIb is larger than −30 dBm (RSSIb> −30 dBm) (step S503).

  If the pre-adjustment RSSIb is greater than −30 dBm in step S503 (YES), the throughput is measured, and the throughput obtained by the measurement is stored in the storage medium 109 as the pre-adjustment throughput Tb (step S504). Subsequently, the power consumption is measured, and the power consumption obtained by the measurement is stored in the storage medium 109 as the power consumption Pcb before adjustment (step S505). Subsequently, the transmission power is lowered by a predetermined value Wc (for example, Wc = 8.0 dBm) (step S506). Subsequently, the throughput is measured, and the throughput obtained by the measurement is stored in the storage medium 109 as the adjusted throughput Ta (step S507).

  Following step S507, it is determined whether the pre-adjustment throughput Tb is equal to or less than the adjusted throughput Ta (step S508). If the pre-adjustment throughput Tb is equal to or less than the adjusted throughput Ta in step S508, the power consumption is measured, and the power consumption obtained by the measurement is stored in the storage medium 109 as the adjusted power consumption Pca (step S509). If the pre-adjustment throughput Tb is larger than the adjusted throughput Tb in step S508, the transmission power is increased by a predetermined value Wd (step S510), and the process returns to step S507. Here, the predetermined value Wd is a value smaller than the predetermined value Wc. For example, when Wc = 8.0 dBm, Wd = 0.5 dBm.

  In step S503, when the RSSIb before adjustment is −30 dBm or less (RSSIb ≦ −30 dBm) (in the case of NO), the process proceeds to the processing flow shown in FIG. In the processing flow shown in FIG. 12, first, noise is measured, and the noise obtained by the measurement is stored in the storage medium 109 as pre-adjustment noise Nb (step S511). Subsequently, power consumption is measured, and the power consumption obtained by the measurement is stored in the storage medium 109 as pre-adjustment power consumption Pcb (step S512).

  Subsequent to step S512, the transmission power is lowered by a predetermined value Wc (for example, Wc = 8.0 dBm) (step S513). Subsequently, RSSI is measured, and the RSSI obtained by the measurement is stored in the storage medium 109 as the adjusted RSSIa (step S514). Subsequently, noise is measured, and the noise obtained by the measurement is stored in the storage medium 109 as adjusted noise Na (step S515). Subsequently, the S / N ratio before adjustment (RSSIb before adjustment−noise Nb before adjustment) and the S / N ratio after adjustment (RSSIa after adjustment−noise Na after adjustment) are calculated, and the S / N ratio before adjustment is adjusted. It is determined whether or not it is less than the rear S / N ratio (step S516). In step S516, when the pre-adjustment S / N ratio is equal to or less than the adjusted S / N ratio (in the case of YES), the power consumption is measured, and the power consumption obtained by the measurement is used as the adjusted power consumption Pca. (Step S517). If the pre-adjustment S / N ratio is greater than the post-adjustment S / N ratio in step S516, the transmission power is increased by a predetermined value Wd (step S518), and the process returns to step S514.

  As described above, in the present embodiment, the transmission power is adjusted so that the S / N ratio is equal to or higher than the current value while maintaining the direction of the antenna 103 at the adjusted antenna angle. Also, if the measurement results include those whose RSSI is greater than −30 dBm (RSSI> −30 dBm), the antenna orientation is maintained at the adjusted antenna angle so that the throughput is equal to or greater than the current value. Adjust the transmission power. Thereby, it is possible to satisfactorily optimize the transmission power while maintaining the communication speed. Also, by optimizing the transmission power, the communication speed can be improved without unnecessarily increasing the power consumption.

[Embodiment 3]
The third embodiment of the present invention will be described below with reference to the drawings. Note that portions common to Embodiment 1 are denoted by common reference numerals, and description thereof is omitted.
The schematic configuration of the wireless slave device according to the third embodiment is the same as the schematic configuration of the wireless slave device 101 shown in FIG. Further, the processing for clarifying the maximum movable range of the antenna 103 in the measurement unit 107 of the wireless slave device 101 is the same as the processing described with reference to FIG. 3 in the first embodiment.

  In the first embodiment, the antenna angle at which the S / N ratio is substantially maximized within the maximum movable range of the antenna 103 in the measurement unit 107 is extracted, and the direction of the antenna 103 becomes the antenna angle. In the adjustment process, the detection process of the orientation of the antenna 103 at which the S / N ratio is substantially maximized is performed in two stages. That is, as a first step, RSSI, noise and power consumption are measured at a predetermined rotation angle (first rotation angle Δθ1) which is a relatively coarse rotation angle, and the S / N ratio is relatively high. Make an orientation of the antenna orientation. Then, as a second stage, RSSI, noise and power consumption at small rotation angles smaller than the first rotation angle Δθ1 (second rotation angle Δθ2) in the vicinity of the antenna direction where the S / N ratio becomes relatively high. And the direction of the antenna having the highest S / N ratio is detected.

  On the other hand, in the present embodiment, the detection process of the direction of the antenna 103 at which the S / N ratio is substantially maximized is performed in one stage. That is, the predetermined rotation angle (first rotation angle Δθ1) is not set to a relatively coarse angle as in the first embodiment, but is the same as the minute rotation angle (second rotation angle Δθ2) in the first embodiment. Set the rotation angle to a fine level.

  FIG. 13 is a flowchart showing a process flow when the measurement unit 107 performs the process of detecting the orientation of the antenna 103 in which the S / N ratio is substantially maximized within the maximum movable range of the antenna 103 in one step. is there. As shown in FIG. 13, first, the antenna 103 is moved to the minus limit of the maximum movable range (step S601). Then, the antenna angle n is set to zero (n = 0) (step S602). Subsequently, RSSI, noise, and power consumption are measured (step S603). The measured RSSI, noise, and power consumption measurement results are stored in the storage medium 109 in association with the antenna angle n (step S604).

  Following step S604, it is determined whether the antenna angle n is equal to the plus limit of the maximum movable range (step S605). If it is determined in step S605 that the antenna angle n is not equal to the plus limit of the maximum movable range (NO), the antenna 103 is rotated in the plus rotation direction by the first rotation angle Δθ1 (step S606). Then, after adding the first rotation angle Δθ1 to the antenna angle n (n = n + Δθ1) to update the antenna angle n (step S607), the process returns to step S603. On the other hand, if it is determined in step S605 that the antenna angle n is equal to the plus limit of the maximum movable range (in the case of YES), the antenna angle having the highest S / N ratio is extracted as the optimum antenna angle V from the measurement results. (Step S608). Then, the orientation of the antenna 103 is adjusted so that the orientation of the antenna 103 becomes the optimum antenna angle V (step S609).

  By doing so, although the processing efficiency is worse than when processing is performed as in FIGS. 4 and 6 of the first embodiment, the direction of the antenna is optimized in communication with the wireless master unit, and the communication speed is increased. Can be substantially maximized.

  In the measurement result obtained by the processing flow shown in FIG. 13, if the RSSI is greater than −30 dBm (RSSI> −30 dBm), the process of step S608 in FIG. The optimum antenna angle V may be extracted by measuring the throughput and comparing the measurement results of the throughput. That is, the processes of FIGS. 8 and 9 in the first embodiment may be performed. In the present embodiment, the processes described in the second embodiment may be combined.

  In the above-described embodiments, the present invention has been described as a hardware configuration, but the present invention is not limited to this. The present invention can also realize each process by causing a CPU (Central Processing Unit) to execute a control program.

  In the above example, the control program can be stored and provided to a computer using various types of non-transitory computer readable media. Non-transitory computer readable media include various types of tangible storage media. Examples of non-transitory computer-readable media include magnetic recording media (for example, flexible disks, magnetic tapes, hard disk drives), magneto-optical recording media (for example, magneto-optical disks), CD-ROMs (Read Only Memory), CD-Rs, CD-R / W, semiconductor memory (for example, mask ROM, PROM (Programmable ROM), EPROM (Erasable PROM), flash ROM, RAM (Random Access Memory), and various types of temporary programs. Computer-readable media may be provided to a computer by way of example, such as electrical signals, optical signals, and electromagnetic waves. The temporary computer-readable medium can supply the program to the computer via a wired communication path such as an electric wire and an optical fiber, or a wireless communication path.

  Note that the present invention is not limited to the above-described embodiment, and can be changed as appropriate without departing from the spirit of the present invention. For example, in the above embodiment, the measurement result of the S / N ratio with respect to the antenna direction may be posted on the Web GUI so that the user can browse the S / N ratio with respect to the antenna direction in the wireless slave unit. Good. By doing in this way, the user can confirm easily the quality of a communication state with a wireless main | base station.

DESCRIPTION OF SYMBOLS 1,101 Radio | wireless subunit | mobile_unit 3,103 Antenna 4,104 Movable part 7 Measuring part 9,109 Storage medium 102 Radio | wireless subunit | mobile_unit main body 105,122 Wireless I / F
106 Movable I / F
107 Measurement Unit 108 Wattmeter 110 External Power Supply 121 Wireless Router

Claims (8)

An antenna that is configured to be able to change the orientation and communicates with the wireless master unit,
A movable part for rotating the antenna;
A control unit for controlling the movable unit to adjust the direction of the antenna and measuring RSSI and noise in communication with the wireless master unit;
The measurement unit changes an antenna angle that defines the direction of the antenna at predetermined rotation angle increments, measures RSSI and noise at each antenna angle in the predetermined rotation angle increments, and performs RSSI and noise at each antenna angle. The S / N ratio is calculated from the measurement result, and the direction of the antenna is adjusted to be the antenna angle corresponding to the highest S / N ratio calculated from the measurement result ,
When there is a measured RSSI that is greater than a predetermined value, the measurement unit may reduce throughput at an antenna angle at which the RSSI is greater than a predetermined value and an antenna angle at which the S / N ratio is maximum. A wireless slave device that measures and adjusts the direction of the antenna so that the antenna angle has the highest throughput among the antenna angles at which the throughput is measured .   The measurement unit further includes a minute rotation angle smaller than the predetermined rotation angle within a predetermined range in the vicinity of the antenna angle corresponding to the highest S / N ratio calculated from the measurement result. Change in increments, measure RSSI and noise at each antenna angle in minute rotation angle increments, calculate the S / N ratio from the measurement results of RSSI and noise at each antenna angle, and the direction of the antenna is the measurement result The wireless slave device according to claim 1, wherein adjustment is performed so that an antenna angle corresponding to a highest one of the calculated S / N ratios is obtained.   3. The wireless slave device according to claim 1, wherein the measurement unit adjusts transmission power so that an S / N ratio is equal to or greater than a current value while maintaining the antenna direction at the adjusted antenna angle. 4. The wireless slave device according to claim 1 , wherein the measurement unit maintains the antenna orientation at the adjusted antenna angle and adjusts the transmission power so that the throughput is equal to or higher than a current value. A method for controlling a wireless slave device comprising: an antenna configured to be capable of changing a direction and performing communication with a wireless master device; and a movable unit that rotates the antenna.
Changing the antenna angle defining the direction of the antenna in predetermined rotation angle increments, and measuring RSSI and noise at each antenna angle in the predetermined rotation angle increments;
The S / N ratio is calculated from the RSSI and noise measurement results at each antenna angle, and the antenna direction is adjusted to the antenna angle corresponding to the highest S / N ratio calculated from the measurement results. And steps to
When there is a measured RSSI larger than a predetermined value, the throughput is measured at the antenna angle at which the RSSI is larger than the predetermined value and the antenna angle at which the S / N ratio is maximum, Adjusting the direction of the antenna so that the antenna angle having the highest throughput among the antenna angles at which the throughput is measured is adjusted . The method of controlling a wireless slave device according to claim 5 , further comprising the step of adjusting the transmission power so that the S / N ratio becomes equal to or greater than a current value while maintaining the antenna direction at the adjusted antenna angle. The method of controlling a wireless slave device according to claim 5 , further comprising: adjusting the transmission power so that the antenna orientation is maintained at the adjusted antenna angle and the throughput is equal to or greater than a current value. A control program for controlling a wireless slave device comprising an antenna configured to be capable of changing a direction and performing communication with a wireless master device, and a movable unit that rotates the antenna,
A process of changing the antenna angle that defines the direction of the antenna in predetermined rotation angle increments, and measuring RSSI and noise at each antenna angle in the predetermined rotation angle increments;
The S / N ratio is calculated from the RSSI and noise measurement results at each antenna angle, and the antenna direction is adjusted to the antenna angle corresponding to the highest S / N ratio calculated from the measurement results. Processing to
When there is a measured RSSI larger than a predetermined value, the throughput is measured at the antenna angle at which the RSSI is larger than the predetermined value and the antenna angle at which the S / N ratio is maximum, A control program for causing a computer to execute a process of adjusting the antenna direction so that the antenna angle having the largest throughput among the antenna angles at which the throughput is measured is adjusted .

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