WO2022044840A1

WO2022044840A1 - Wireless device

Info

Publication number: WO2022044840A1
Application number: PCT/JP2021/029774
Authority: WO
Inventors: 修小堺; 雅博宇野; 崇之平林; 徹寺島; 雄二村山
Original assignee: ソニーセミコンダクタソリューションズ株式会社
Priority date: 2020-08-31
Filing date: 2021-08-12
Publication date: 2022-03-03
Also published as: CN116057851A

Abstract

A wireless device of this disclosure comprises: a plurality of antennas that have mutually different directivities and transmit/receive signals to/from communication partners; an extraction unit that extracts each reference signal included in each reception signal received by each of the plurality of antennas; a control unit that selects, from among the plurality of antennas, one antenna having a directivity suitable for transmission, on the basis of information obtained from the reference signals extracted by the extraction unit; and a transmission circuit that transmits a signal to a communication partner using the one antenna selected by the control unit.

Description

Wireless device

This disclosure relates to a wireless device having a plurality of antennas.

In wireless communication, various techniques for improving communication quality have been proposed (see Patent Documents 1 and 2). On the other hand, for example, smart meters used for gas meters and water meters may be installed underground or in the back of a building, and it is necessary to be able to communicate even in an environment with poor radio wave environment, and there are cases where power cannot be secured. Therefore, it is necessary to drive it for a long time with a battery.

Japanese Unexamined Patent Publication No. 9-247060 Japanese Unexamined Patent Publication No. 2004-242151

Wireless devices used for smart meters and the like are required to improve communication quality while suppressing power consumption.

It is desirable to provide a wireless device that can improve communication quality while suppressing power consumption.

The wireless device according to the embodiment of the present disclosure has different directivities from each other, and has a plurality of antennas for transmitting and receiving signals to and from a communication partner, and each received signal received by each of the plurality of antennas. Control to select one antenna having directivity suitable for transmission from a plurality of antennas based on the extraction unit that extracts each included reference signal and the information obtained from each reference signal extracted by the extraction unit. It includes a unit and a transmission circuit that transmits a signal to a communication partner using one antenna selected by the control unit.

In the wireless device according to the embodiment of the present disclosure, among the plurality of antennas, based on the information obtained from each reference signal included in each received signal received by each of the plurality of antennas having different directivity. Select one antenna with directivity suitable for transmission.

It is a block diagram which shows typically one configuration example of the wireless device which concerns on 1st Embodiment of this disclosure. It is explanatory drawing which shows typically an example of the installation environment of the wireless device which concerns on 1st Embodiment. It is explanatory drawing which shows an example of the frequency characteristic of the propagation loss between a radio device and a base station in the installation environment shown in FIG. It is explanatory drawing which shows an example of the structure of a wireless frame. It is explanatory drawing which shows an example of the communication protocol of wireless communication. It is explanatory drawing which shows an example of the physical channel in the downlink direction in one frame period of wireless communication. It is explanatory drawing which shows an example of the index value which can measure based on a reference signal. It is explanatory drawing which shows an example of the frequency characteristic of a received signal. It is explanatory drawing which shows an example of the standard deviation of the level fluctuation of the received signal when the frequency bandwidth to be averaged is changed. It is a flow chart schematically showing an example of the flow of the whole communication processing of the wireless device which concerns on 1st Embodiment. It is explanatory drawing which shows the main part of the radio apparatus which concerns on modification 1. FIG.

Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. The explanation will be given in the following order.
0. Comparative example 1. First Embodiment (FIGS. 1 to 11)
1.1 Configuration 1.2 Operation 1.3 Effect 1.4 Modification example 2. Other embodiments

<0. Comparative example>
Patent Document 1 (Japanese Unexamined Patent Publication No. 9-247060) proposes a technique that enables effective transmission space diversity even in a communication method in which transmission and reception have different carrier frequencies. As a method, it has been proposed to switch the transmission space diversity control signal based on the reception quality information of the partner station transmitted by the partner station. In this technology, reception quality information is sent from the communication partner, it is determined whether the transmitting antenna selected by the own station is appropriate, and if it is not appropriate, the transmitting antenna of the own station is switched. In the case of this technology, additional communication from the communication partner to the own station is required, which consumes extra power and uses communication resources.

According to Patent Document 2 (Japanese Unexamined Patent Publication No. 2004-242151), in digital wireless transmission, high-precision directivity control in downlink communication can be performed even when the propagation environments of uplink communication and downlink communication are different, and the throughput is increased. Technologies that make it possible to improve have been proposed. Similar to Patent Document 1, the technique described in Patent Document 2 also requires feedback information from the communication partner, and additional communication from the communication partner to the own station is required, resulting in extra power consumption and additional power consumption. It uses communication resources.

On the other hand, in so-called IoT (Internet of Things) devices, efficient collection of sensor information by automatically collecting information measured by sensors by communication and efficient operation based on the information are required. .. IoT devices used for such applications are required to be battery-powered for a long period of time, for example, water meters are required to continue to operate for 8 years, gas meters for 10 years without battery replacement.

MTC (Machine Type Communication) terminals such as smart meters used for gas meters and water meters may be installed underground or in the back of a building, so it is necessary to be able to communicate even in an environment with poor radio wave environment. In addition, there are cases where power cannot be secured, so it is necessary to drive the battery for a long time.

Based on such demands, 3GPP (Third Generation Partnership Project) has standardized a system that can operate for 10 years or more with a 20 dB coverage expansion and a 5 Wh battery compared to the existing system as an MTC system. The main function introduced for the 20 dB coverage expansion is the repetitive transmission function, and the repetitive transmission function of up to 2048 times is standardized. On the other hand, the main functions introduced to extend the battery life are eDRX (Extended Discontinuous Reception) and PSM (Power Save Mode). However, the repetitive transmission function has a problem that the battery life is significantly shortened because the power consumption due to the repetitive transmission for establishing communication increases in an environment where the radio wave environment is severe. Further, since the eDRX and PSM have a function of reducing the electric power during non-communication, there is a problem that the electric power during communication cannot be reduced.

As a method for improving communication quality, there is antenna diversity as a method other than the above-mentioned repetitive transmission function. Antenna diversity takes advantage of the different communication qualities of multiple antennas or directivity in a propagation environment to improve communication performance by selecting the optimal antenna or directivity. If the communication quality can be improved in antenna diversity, the above-mentioned repetitive transmission function can be not used or the number of repetitive transmissions can be reduced. Therefore, it is effective to apply diversity to transmission in order to reduce transmission power, but conventionally, as in the techniques shown in

Patent Documents

1 and 2 above, an antenna (directivity) suitable for transmission is used. Feedback from the other party is usually needed to confirm the selection. However, IoT devices such as gas meters and water meters are required to be battery-powered for a long time, that is, extremely low power consumption, and the generation of extra communication leads to an increase in power consumption. It is meaningless if the power consumption increases due to the operation of transmission diversity for low power consumption.

Therefore, in the present embodiment, as described below, it is possible to select an appropriate antenna (directivity) while suppressing an increase in power consumption, paying particular attention to the large power consumption during transmission. Propose technology. This makes it possible to realize good communication quality without using the repetitive transmission function (or even if the number of repetitive transmissions is reduced).

<1. First Embodiment>
[1.1 Configuration]
FIG. 1 schematically shows a configuration example of a wireless device 100 according to the first embodiment of the present disclosure.

The wireless device 100 has different directivities from each other, and includes a plurality of antennas for transmitting and receiving signals to and from a communication partner. FIG. 1 shows an example in which a plurality of antennas are composed of a first antenna 11 having directivity 1 and a second antenna 12 having directivity 2. However, a plurality of antennas may be composed of three or more antennas having different directivities from each other.

The communication partner of the wireless device 100 is, for example, a base station 200. The wireless device 100 may be able to communicate with each of the plurality of base stations 200 as a communication partner. The base station 200 has one or more base station antennas 201 as communication antennas. The wireless device 100 may be capable of communicating with each of the plurality of base station antennas 201 included in one base station 200.

The wireless device 100 includes a directional changeover switch SW1, a transmission / reception changeover switch SW2, a reception circuit 21, a demodulator 22, a reference signal extraction unit 23, a transmission circuit 31, a modulator 32, and a transmission signal generation unit 33. And a control unit 40 are further provided.

The directivity changeover switch SW1 switches which of the first antenna 11 and the second antenna 12 is used for transmitting and receiving signals based on the control of the control unit 40.

The transmission / reception changeover switch SW2 switches between receiving a signal and transmitting a signal based on the control of the control unit 40.

The receiving circuit 21 receives a signal via the first antenna 11 or the second antenna 12.

The demodulator 22 demodulates the signal received by the receiving circuit 21.

The reference signal extraction unit 23 is an extraction unit that extracts each reference signal included in each received signal received by each of the first antenna 11 and the second antenna 12. Here, the reference signal is, for example, the reference signal (RS) shown in FIGS. 4 and 7 described later.

The first antenna 11 and the second antenna 12 may each be able to receive signals from a plurality of base station antennas 201 included in the base station 200. In this case, the reference signal extraction unit 23 may extract each reference signal included in each received signal from the plurality of base station antennas 201 possessed by the base station 200 which is the communication partner.

The first antenna 11 and the second antenna 12 may each be able to receive signals from a plurality of base stations 200. In this case, the reference signal extraction unit 23 may extract each reference signal included in each received signal from the plurality of base stations 200.

The first antenna 11 and the second antenna 12 may each be capable of receiving signals in a plurality of frequency bands. In this case, the reference signal extraction unit 23 may extract each reference signal included in each received signal in a plurality of frequency bands.

The control unit 40 has a calculation unit 41 and a memory 42. The memory 42 stores various data such as various programs executed by the wireless device 100 and calculation results by the calculation unit 41. The arithmetic unit 41 has, for example, a CPU (Central Processing Unit). In the control unit 40, for example, the calculation unit 41 executes a program read from the memory 42 to perform various signal processing, calculation processing, and the like.

The control unit 40 selects one of the first antenna 11 and the second antenna 12 having a directivity suitable for transmission based on the information obtained from each reference signal extracted by the reference signal extraction unit 23. do.

The first antenna 11 and the second antenna 12 can each receive a plurality of received signals having different signal characteristics. The control unit 40 is based on, for example, an averaged value of the received signal levels of a plurality of reference signals extracted from the plurality of received signals, or a median value, or a value obtained by a combination of the averaged value and the median value. Therefore, one antenna having a directivity suitable for transmission may be selected from the first antenna 11 and the second antenna 12.

Predetermined measurement information measured by the measuring device 300 is input to the control unit 40. The measuring device 300 is, for example, a gas meter, a water meter, or the like. The control unit 40 causes the transmission signal generation unit 33 to generate a transmission signal including predetermined measurement information measured by the measurement device 300.

The transmission signal generation unit 33 generates a transmission signal including predetermined measurement information measured by the measuring device 300 based on the control of the control unit 40.

The modulator 32 modulates the transmission signal generated by the transmission signal generation unit 33 by a predetermined modulation method.

The transmission circuit 31 transmits a transmission signal including measurement information to the base station 200 using one of the first antenna 11 and the second antenna 12 selected by the control unit 40.

The installation location of the first antenna 11 and the second antenna 12 may be unchanged at least during a predetermined communication period required for transmitting predetermined information. Here, the predetermined information is, for example, predetermined measurement information measured by the measuring device 300.

The transmission circuit 31 may transmit a transmission signal to the base station 200 a plurality of times during a predetermined communication period. In this case, the control unit 40 selects one antenna having a directivity suitable for transmission before the first transmission of the signal in the predetermined communication period, and the selected state is at least during the predetermined communication period. May continue to be maintained. Here, the period before the first transmission of the signal in the predetermined communication period may be, for example, the period Tr shown in FIGS. 5 and 10 described later.

[1.2 Operation]
Hereinafter, a communication operation and a communication method using the wireless device 100 will be described with specific examples.

(Example of installation environment)
FIG. 2 schematically shows an example of the installation environment of the wireless device 100.

The wireless device 100 can be mounted on an MTC terminal such as a smart meter used for a gas meter or a water meter. It is assumed that the terminal equipped with the wireless device 100 is fixedly installed in an environment where the radio wave environment is poor (difficult to reach), such as the underground parking lot 50 shown in FIG. The direction D1 in FIG. 2 corresponds to the directivity 1 of the first antenna 11 included in the wireless device 100. The direction D2 in FIG. 2 corresponds to the directivity 2 of the second antenna 12 included in the wireless device 100. Under the environment of FIG. 2, the radio wave propagating through the inlet 51 is reflected by the wall surface 52 and the like, and is received by the first antenna 11 and the second antenna 12 of the wireless device 100 (in a multipath) from a plurality of directions. Will be done.

The characteristics of radio wave propagation in such an environment include the following.
-Propagation loss = "direction bias" + "multipath effect". The directional bias corresponds to the bias in the arrival direction of the radio wave.
-The directional bias has a high correlation even if the frequency is different between the downlink (DL (Down Link)) and the uplink (UL (Up Link)).

In the wireless device 100, by utilizing the above-mentioned radio wave propagation characteristics and detecting the directional bias using only the received signal, it is possible to realize the optimum antenna selection at the time of transmission without increasing the power consumption as much as possible. To.

FIG. 3 shows an example of the frequency characteristics of the propagation loss between the wireless device 100 and the base station 200 in the installation environment shown in FIG. FIG. 3 shows an example of the frequency characteristics of each of the directions D1 and D2. As shown in FIG. 3, the directional bias refers to the bias in the arrival direction of the radio wave, and is indicated by the broken line in FIG. It is desirable to judge the directional bias by the average value of propagation loss in a sufficiently wide frequency band. Judging the directional bias in a narrow band is likely to make a mistake. In the environment of FIG. 2, more radio waves arrive in the direction D1 than in the direction D2. Therefore, as shown in FIG. 3, "direction bias in direction D1"> "direction bias in direction D2". ".

In the wireless device 100, the optimum directivity for transmission is determined by utilizing such characteristics, and the optimum antenna for transmission is selected.

(Wireless frame configuration example)
FIG. 4 shows an example of the configuration of a wireless frame used for communication of the wireless device 100. FIG. 4 shows the configuration of a downlink radio frame used in an LTE (Long Term Evolution) system.

In the downlink wireless frame used in the LTE system, one frame is 10 ms and is composed of 10 subframes. One subframe is 1 ms and is composed of two slots. One slot is composed of N frequency-divisioned resource blocks (RBs). One resource block is composed of a plurality of resource elements. A plurality of reference signals (RS) are mapped in one resource block.

FIG. 5 shows an example of a communication protocol for wireless communication. FIG. 6 shows an example of a downlink physical channel in one frame period of wireless communication.

FIG. 5 shows the communication required for exchanging one message in category M (Cat-M) shown in "Ericsson, et al., R1-1706161 Early Data Transmission for MTC, 3GPP RAN1 Meeting # 88bis, 2017." ing. Here, one message corresponds to predetermined information transmitted by the wireless device 100 (for example, predetermined measurement information measured by the measuring device 300). The period required for exchanging one message includes a plurality of transmissions, but if the optimum antenna (directivity) is reselected for each transmission timing, the power consumption required there will increase. As described above, the installation environment assumed in this embodiment is assumed to be a fixed installation such as a smart meter. Under such an environment, it is said that the propagation environment does not change or fluctuates very slowly with respect to the elapsed time. Therefore, the optimum antenna once selected continues to be optimum for one message exchange period, so that the power consumption is not unnecessarily increased.

In the LTE system, radio waves are always emitted from the base station 200, and as shown in FIG. 5, a synchronization signal (SS: Synchronization Signal) is always transmitted at a fixed timing and a fixed frequency. As shown in FIG. 6, the base station 200 transmits a synchronization signal (SS) a plurality of times in a period of one frame. The synchronization signal (SS) includes a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). If synchronization is possible here, PBCH (Physical Broadcast Channel) and PDSCH (Physical Downlink Shared Channel) can be demodulated. After that, PRACH (Physical Randam Access Channel) is transmitted as the first transmission.

In the LTE system, it is necessary to receive a reference signal (RS) in order to receive and demodulate a signal (downlink signal) from PBCH or other base station 200. The reference signal (RS) is continuously transmitted from the base station 200 at a predetermined timing and at a predetermined frequency. By receiving this reference signal (RS), index values such as RSRP (Reference Signal Received Power), SIR (Signal to Interference Retio), RSSI (Received Signal Strength Indicator), and RSRQ (Reference Signal Received Quality) can be calculated. Can be done. In the LTE system, since the timing must be known in order to receive the reference signal (RS), it is necessary to receive the PSS and SSS first.

FIG. 7 shows an example of an index value that can be measured based on the reference signal (RS).

RSRP is the received power (received signal level) of the reference signal (RS) per resource element.

RSSI is the total received power (received signal level) of the OFDM symbol (resource element of all frequencies) in which the reference signal (RS) is present.

RSRQ is one of the indexes showing the reception quality of the reference signal (RS), is calculated by the ratio of RSRP and RSSI, and is a value normalized by the number N of resource blocks as follows.
RSRQ = RSRP × N / RSSI
Considering per resource block, it has the same meaning as RSRQ = RSRP / (RSSI / N).

Similar to RSRQ, SIR is one of the indexes showing the reception quality of the reference signal (RS), and is the ratio of the received power (RSRP) and the interference power (interference level) of the reference signal (RS). In the calculation of RSRQ, RSSI, that is, the received power in the entire frequency band of the resource element is used as the denominator, but in SIR, the interference power existing in the frequency band of one reference signal (RS) is used as the denominator. Since it is difficult to directly measure the interference power, the interference power is obtained by calculating the variation (dispersion) of the ideal signal of the reference signal (RS). The interference power calculated by such a method is also called SINR because it includes a noise component in addition to a signal from an adjacent cell in the same frequency band.

(Desirable operation example)
In the wireless device 100, the directivity selection (antenna selection) is performed based on the information obtained by receiving the reference signal (RS) transmitted from the base station 200. As described above, the directional bias has a high correlation between DL and UL even if the frequencies are different. Therefore, when selecting the optimum antenna, the directional bias obtained by using the received signal is used. It is possible.

In the wireless device 100, when selecting the directivity (selecting the antenna), all the reference signals (RS) transmitted from the two or more base station antennas 201 of the one or more candidate base stations 200 are used as the received signals. Is desirable. In the LTE system, a reference signal (RS) is constantly transmitted periodically on the downlink from the base station 200 to the wireless device 100 (FIG. 4). The reference signal (RS) is mapped to the resource element determined for each base station antenna 201. Normally, the wireless device 100 side can know its own propagation environment by demodulating the reference signal (RS) and calculating index values such as RSRP, RSRQ, and SIR. This reference signal (RS) can also be utilized in this embodiment. In the wireless device 100, by using reference signals (RS) from a plurality of base station antennas 201, it is possible to reduce the bias of propagation fluctuations and to know a more accurate direction vise.

It is desirable that the wireless device 100 receives signals in a plurality of frequency bands. In this case, it is desirable that the reference signal extraction unit 23 extracts each reference signal (RS) included in each received signal in a plurality of frequency bands. Since the reference signal (RS) is transmitted in all of the plurality of frequency bands serviced by the operator, and the directional bias does not depend on the frequency band but depends on the installation environment of the wireless device 100, it communicates by itself. By further using a reference signal (RS) in a frequency band other than that used for, the observation accuracy of the directional bias can be improved.

In the wireless device 100, the received signal levels of a plurality of reference signals (RS) extracted from the plurality of received signals are averaged or median, or based on a value obtained by a combination of the averaged value and the median. Therefore, it is desirable to select a directivity suitable for transmission. Usually, in the LTE system, as described above, RSRP, RSSI, RSRQ, SINR and the like are obtained by using the reference signal (RS). RSSI includes noise and interference level in addition to the received signal level of the reference signal (RS), and is not suitable for obtaining a directional vise. Similarly, RSRQ and SINR are also unsuitable, and in the present embodiment, when obtaining a directional vise, RSRP (reception signal level of reference signal (RS)) is set in the frequency direction, a plurality of base station antennas 201, and a plurality of base station antennas 201. It is preferable to use the averaged value or the median value for the frequency band, or the value obtained by the combination of the averaged value and the median value.

FIG. 8 shows an example of the frequency characteristics of the received signal. FIG. 9 shows an example of the standard deviation of the level variation of the received signal when the frequency bandwidth to be averaged is changed. FIG. 9 shows an example of the case where the base station antenna 201 is one and the case where the base station antenna 201 is two.

For example, in the installation environment as shown in FIG. 2, the strength of the received signal level has frequency characteristics as shown in FIG. 8 due to the influence of multipath. Increasing the averaging bandwidth reduces the variance of level variation as shown in FIG. Dispersion can be further reduced by using uncorrelated received signal levels from the plurality of base station antennas 201.

In the wireless device 100, one antenna having a directivity suitable for transmission is selected before the first transmission of the signal in a predetermined communication period, and the selected state is maintained for at least a predetermined communication period. It is desirable to continue. Here, the period before the first transmission of the signal in the predetermined communication period may be, for example, the period Tr shown in FIG. 5 described later. For example, in an LTE system, as shown in FIG. 5, since the exchange of one message includes a plurality of transmissions, it is desirable to complete the selection of the optimum antenna before the first transmission, PRACH. In the LTE system, the reference signal (RS) can be received by the time synchronization (PSS, SSS) after the wireless device 100 is started. Therefore, the antenna suitable for the period Tr after receiving the PSS and SSS and before the transmission of the PRACH. It is desirable to complete the selection of. Further, since the power consumption when the wireless device 100 transmits is large, it is desirable to finish the selection of the antenna before that.

Considering that the installation location of the wireless device 100 is fixed, the antenna may be selected every time the wireless device 100 is started, or once when the wireless device 100 is first installed. You may just run it. Further, it may be executed periodically, such as once a day.

(Flow of communication processing)
FIG. 10 schematically shows an example of the overall communication processing flow of the wireless device 100 according to the first embodiment.

When the wireless device 100 is activated (step S101), first, synchronization processing is performed (step S102). For example, in the example of FIG. 5, synchronization processing is performed by receiving a Primary synchronization signal (PSS) and a Secondary synchronization signal (SSS). The wireless device 100 is activated at a timing when it becomes necessary to transmit a predetermined periodic message (for example, predetermined measurement information measured by the measuring device 300) (for example, every 10 hours). , Every few days, every few weeks). It also starts when an interrupt-like message occurs (step S102).

Next, the wireless device 100 performs a directivity (antenna) switching process by switching the directivity changeover switch SW1 based on the control of the control unit 40 (step S103). Next, the wireless device 100 performs reception processing of the reference signal (reference signal (RS)) (step S104).

Next, the wireless device 100 determines whether or not all directivity (antennas) have been switched (step S106). This determination is made by the control unit 40. If it is determined that all the directivities have not been switched (step S106; N), the radio device 100 returns to the process of step S104.

When it is determined that all the directivities have been switched (step S106; Y), the wireless device 100 next compares the received signal levels for each directivity and selects the optimum directivity (antenna) (step). S107). These processes are performed by the control unit 40. It is desirable that the processing of steps S104 to S107 is performed, for example, during the period Tr shown in FIG.

Next, the wireless device 100 transmits a message with the selected directivity (antenna) (step S108). Next, the wireless device 100 enters a pause period (step S109).

Next, the wireless device 100 determines whether or not a certain period of time has passed (step S110). If it is determined that the period has not elapsed (step S110; N), the wireless device 100 returns to the process of step S109 and continues the pause period. When it is determined that a certain period of time has passed (step S110; Y), the wireless device 100 returns to the process of step S101.

[1.3 Effect]
As described above, according to the radio device 100 according to the first embodiment, information obtained from each reference signal (reference signal (RS)) included in each received signal received by each of the plurality of antennas. Since one antenna having a directivity suitable for transmission is selected from the plurality of antennas based on the above, it is possible to improve the communication quality while suppressing the power consumption.

Further, according to the wireless device 100 according to the first embodiment, the optimum transmitting antenna can be selected only from the signal obtained by reception without adding extra transmission, so that the communication quality can be improved. .. As a result, it is possible to avoid the repetition of transmission or reduce the number of repetitions, so that the transmission power can be reduced. This makes it possible to realize a long battery drive time of the wireless device 100.

It should be noted that the effects described in the present specification are merely examples and are not limited, and other effects may be obtained. The same applies to the effects of the other embodiments thereafter.

[1.4 Modification example]
(Modification 1)
FIG. 11 shows a main part of the wireless device 100 according to the first modification.

In the wireless device 100, each of the plurality of antennas can transmit and receive signals to and from the communication partner in a time-division manner, and the directivity at the time of transmission and the directivity at the time of reception are different. May be good.

In order to improve the measurement accuracy of the directional bias, it is preferable to perform a directional search using a directional antenna with a high directional gain, but in transmission, the directional gain is extremely high due to the stability of propagation and other reasons. You may not want to use a sex antenna. In such a case, antennas having different directional gains at the time of reception and at the time of transmission for observing the directional bias may be used.

For example, in the wireless device 100, when selecting the optimum antenna (directivity), an antenna having as thin a directivity as possible is used to scan the space evenly, receive radio waves, select the optimum directivity, and apply it to transmission. Is desirable. However, in each country, the maximum antenna directivity gain and the maximum effective isotropic radiated power (EIRP (“Equivalent Isotropic Radiated Power” or “Effective Isotropic Radiated Power”)) at the time of transmission are usually limited by the Radio Law. In such a case, as shown in FIG. 11, when receiving without being restricted by the Radio Law, a high gain narrow directivity antenna is used to find the optimum direction, and when transmitting, the directivity is wide enough to comply with the Radio Law. It is best to transmit using the antenna of.

(Modification 2)
In the wireless device 100, the plurality of antennas may be capable of receiving a plurality of received signals having different signal characteristics. The control unit 40 selects one antenna having a directivity suitable for transmission from the plurality of antennas based on a plurality of information obtained from the plurality of reference signals extracted from the plurality of received signals. May be good.

For example, in the wireless device 100, when obtaining a directional bias, a plurality of frequency bands, a plurality of base station antennas 201, and a plurality of reference signals (RS) from a base station 200 other than the base station 200 that actually communicates are used. The reference signal (RS) may be freely combined and utilized. This makes it possible to improve the measurement accuracy of the directional bias.

<2. Other embodiments>
The technique according to the present disclosure is not limited to the description of each of the above embodiments, and various modifications can be carried out.

For example, this technology can also have the following configuration.
According to the present technology having the following configuration, it has a directivity suitable for transmission among a plurality of antennas based on the information obtained from each reference signal included in each received signal received by each of the plurality of antennas. Since one antenna is selected, it is possible to improve the communication quality while suppressing the power consumption.

(1)
Multiple antennas that have different directivity and send and receive signals to and from the communication partner,
An extraction unit that extracts each reference signal included in each received signal received by each of the plurality of antennas, and an extraction unit.
A control unit that selects one antenna having a directivity suitable for transmission from the plurality of antennas based on the information obtained from each of the reference signals extracted by the extraction unit.
A wireless device including a transmission circuit that transmits a signal to the communication partner using the one antenna selected by the control unit.
(2)
The wireless device according to (1) above, wherein the plurality of antennas do not change their installation location at least during a predetermined communication period required for transmitting predetermined information.
(3)
The predetermined information is the predetermined measurement information measured by the measuring device. The wireless device according to (2) above.
(4)
Each of the plurality of antennas can receive signals from the plurality of communication antennas of the communication partner.
The wireless device according to any one of (1) to (3) above, wherein the extraction unit extracts each reference signal included in each received signal from a plurality of communication antennas of the communication partner.
(5)
Each of the plurality of antennas can receive signals from the plurality of communication partners.
The wireless device according to any one of (1) to (4) above, wherein the extraction unit extracts each reference signal included in each received signal from the plurality of communication partners.
(6)
Each of the plurality of antennas can receive signals in a plurality of frequency bands.
The wireless device according to any one of (1) to (5) above, wherein the extraction unit extracts each reference signal included in each received signal in a plurality of frequency bands.
(7)
Each of the plurality of antennas can receive a plurality of received signals having different signal characteristics.
The control unit sets the received signal levels of the plurality of reference signals extracted from the plurality of received signals to an averaged value or a median value, or a value obtained by a combination of the averaged value and the median value. The wireless device according to any one of (1) to (6) above, wherein one antenna having a directivity suitable for transmission is selected from the plurality of antennas.
(8)
Each of the plurality of antennas can transmit and receive a signal to and from the communication partner in a time-division manner, and the directivity at the time of transmission and the directivity at the time of reception are different from the above (1) to. The wireless device according to any one of (7).
(9)
Each of the plurality of antennas can receive a plurality of received signals having different signal characteristics.
The control unit selects one of the plurality of antennas having a directivity suitable for transmission based on a plurality of information obtained from the plurality of reference signals extracted from the plurality of received signals. The wireless device according to any one of (1) to (8) above.
(10)
The transmission circuit transmits a signal to the communication partner a plurality of times during the predetermined communication period.
The control unit selects one antenna having a directivity suitable for transmission before the first transmission of the signal in the predetermined communication period, and selects the selected state at least during the predetermined communication period. The wireless device according to any one of (2) to (9) above.

This application claims priority on the basis of Japanese Patent Application No. 2020-146215 filed at the Japan Patent Office on August 31, 2020, and the entire contents of this application are referred to in this application. Incorporate into the application.

Those skilled in the art may conceive various modifications, combinations, sub-combinations, and changes, depending on design requirements and other factors, which are included in the claims and their equivalents. It is understood that it is one of ordinary skill in the art.

Claims

Multiple antennas that have different directivity and send and receive signals to and from the communication partner,
An extraction unit that extracts each reference signal included in each received signal received by each of the plurality of antennas, and an extraction unit.
A control unit that selects one antenna having a directivity suitable for transmission from the plurality of antennas based on the information obtained from each of the reference signals extracted by the extraction unit.
A wireless device including a transmission circuit that transmits a signal to the communication partner using the one antenna selected by the control unit.
The wireless device according to claim 1, wherein the plurality of antennas have an invariant installation location at least during a predetermined communication period required for transmitting predetermined information.
The wireless device according to claim 2, wherein the predetermined information is predetermined measurement information measured by the measuring device.
Each of the plurality of antennas can receive signals from the plurality of communication antennas of the communication partner.
The wireless device according to claim 1, wherein the extraction unit extracts each reference signal included in each received signal from a plurality of communication antennas of the communication partner.
Each of the plurality of antennas can receive signals from the plurality of communication partners.
The wireless device according to claim 1, wherein the extraction unit extracts each reference signal included in each received signal from the plurality of communication partners.
Each of the plurality of antennas can receive signals in a plurality of frequency bands.
The wireless device according to claim 1, wherein the extraction unit extracts each reference signal included in each received signal in a plurality of frequency bands.
Each of the plurality of antennas can receive a plurality of received signals having different signal characteristics.
The control unit sets the received signal levels of the plurality of reference signals extracted from the plurality of received signals to an averaged value or a median value, or a value obtained by a combination of the averaged value and the median value. The wireless device according to claim 1, wherein one of the plurality of antennas having a directivity suitable for transmission is selected based on the above.
The first aspect of claim 1, wherein each of the plurality of antennas can transmit and receive a signal to and from the communication partner in a time-division manner, and the directivity at the time of transmission and the directivity at the time of reception are different. Wireless device.
Each of the plurality of antennas can receive a plurality of received signals having different signal characteristics.
The control unit selects one of the plurality of antennas having a directivity suitable for transmission based on a plurality of information obtained from the plurality of reference signals extracted from the plurality of received signals. The wireless device according to claim 1.
The transmission circuit transmits a signal to the communication partner a plurality of times during the predetermined communication period.
The control unit selects one antenna having a directivity suitable for transmission before the first transmission of the signal in the predetermined communication period, and selects the selected state at least during the predetermined communication period. The wireless device according to claim 2, which is to be maintained.