WO2012090551A1

WO2012090551A1 - Data collection system, wireless base station and communication method

Info

Publication number: WO2012090551A1
Application number: PCT/JP2011/069540
Authority: WO
Inventors: 孝志望月
Original assignee: 日本電気株式会社
Priority date: 2010-12-28
Filing date: 2011-08-30
Publication date: 2012-07-05
Also published as: JP2014082531A

Abstract

In order to provide a data collection system capable of effectively using non-movement of an object for which data is to be collected, a data collection system of the present invention is provided with: data collection terminals 10-1, 10-2, …, for collecting predetermined data at specific locations; and wireless base stations 20-1, 20-2, …, to which the data collection terminals 10-1, 10-2, …, are wirelessly connected. The wireless base stations 20-1, 20-2, …, are provided with direction memory units 21-1 and 21-2 which store information related to the direction of the specific locations where the data collection terminals 10-1, 10-2, …, have been placed, so that when communicating with the data collection terminals 10-1, 10-2, …, the orientation for formation of radio beams is controlled so that the radio beams face the orientations of the data collection terminals 10-1, 10-2, … on the basis of the information related to the directions stored in the direction memory units 21.

Description

Data collection system, radio base station, and communication method

The present invention relates to a data collection system, a radio base station, and a communication method for collecting data by radio.

Measures are being taken to measure the gas and electricity of each household and to collect information on sales of vending machines using a wireless communication system of a mobile phone. That is, by providing a gas or electricity meter or vending machine with a communication function similar to that of a mobile phone, the gas or electricity meter or vending machine can communicate with a radio base station in the radio communication system of the mobile phone. . Information on gas and electricity meters and vending machines is collected at the center through the wireless communication system of the mobile phone.

There is a technique related to a wireless sensor disclosed in Patent Document 1. In the technique disclosed in Patent Document 1, an adaptive array antenna is provided in an information collection device that collects information from a sensor device. And when there is a transmission request from the sensor device, the information collecting device makes the adaptive array antenna non-directional or changes the directivity to receive the transmission signal from the sensor device, The directivity can be changed according to the reception state of the transmission signal from the apparatus. In the technique described in Patent Document 1, the sensor device is not fixed. The technology described in Patent Document 1 is based on the premise that the information collection device and the sensor device are connected by a wireless LAN (Local Area Network). The technique described in Patent Document 1 does not assume the case where the sensor device is fixed, and the information collection device detects the reception state of the transmission signal from the sensor device in order to change the directivity of the antenna. There is a need to.

Further, Patent Document 2 discloses a technique related to wireless connection between a fixed terminal and a network subsystem such as a base station. In the technique disclosed in Patent Document 2, a network subsystem stores parameters for bidirectional wireless connection with a subscriber terminal having a fixed position, and controls a directional antenna beam based on the parameters. . The technique disclosed in Patent Document 2 relates to the connection between a subscriber telephone terminal and a public telephone network, and is not intended for wireless data collection.

JP 2010-233142 A Special Table 2000-516436

∙ Gas and electricity meters, vending machines, etc. are basically installed in fixed locations, and even if they can move, the range of movement is limited to specific locations. This invention pays attention to this point, and it aims at providing the data collection system which can utilize effectively that the collection object of data does not move.

The main feature of the present invention is that a radio base station is provided with a memory for storing the orientation of the data collection terminal, and a radio beam is formed during communication according to the orientation.

That is, according to the first aspect of the present invention, a data collection terminal that collects predetermined data at a specific location and a radio base station to which the data collection terminal is wirelessly connected are provided. A radio beam in the direction of the data collection terminal based on the information about the direction stored in the direction memory when communicating with the data collection terminal and the direction memory that stores information about the direction of the specific location where the terminal is located And a radio beam control means for controlling the forming direction of the radio beam so as to face.

It is desirable that a base station used for a mobile radio communication system is used as the radio base station, and the data collection terminal is wirelessly connected to the base station as a terminal of the mobile radio communication system.

According to a second aspect of the present invention, for a data collection terminal that collects predetermined data at a specific location, an orientation memory that stores information about the orientation of the specific location where the data collection terminal is located, and data collection Radio beam control means for controlling the formation direction of the radio beam so that the radio beam is directed in the direction of the data collection terminal based on information on the orientation stored in the orientation memory when communicating with the terminal. A featured radio base station is provided.

A data collection terminal is wirelessly connected to this wireless base station as a terminal of a portable wireless communication system.

The radio base station includes a plurality of antennas that perform multi-input / multi-output multi-antenna communication. In the azimuth memory, matrix information that determines directions of radio beams formed by the plurality of antennas is provided as information related to the azimuth. The configuration can be stored. When there are a plurality of data collection terminals, matrix information is stored in the direction memory corresponding to each of the data collection devices.

According to the present invention, it is possible to effectively use the fact that the data collection target does not move.

It is a block block diagram which shows the data collection system which concerns on embodiment of this invention. It is a block diagram which shows the structural example of the uplink part of a radio base station. It is a block diagram which shows the structural example of the downlink part of a wireless base station. It is a block diagram which shows another structural example of a wireless base station, and is a figure which shows the structural example of an uplink part. It is a block diagram which shows the system configuration example in case the number of transmission / reception antennas of a wireless base station is larger than the number of transmission / reception antennas of a data collection terminal.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

[Overall configuration of data collection system]
FIG. 1 is a block configuration diagram showing a data collection system according to an embodiment of the present invention. The data collection system includes data collection terminals 10-1, 10-2,..., Radio base stations 20-1, 20-2,.

Each of the data collection terminals 10-1, 10-2,... Is installed in a specific place such as a meter for measuring the amount of gas, electricity, water, etc. used in each household, or a vending machine. Collect predetermined data such as sales information of vending machines. Further, the data collection terminals 10-1, 10-2,... Are provided with a function of performing wireless communication with the radio base stations 20-1, 20-2,. Since the configuration for data collection and the configuration for wireless communication are well known to those skilled in the art and are not directly related to the present invention, the detailed configuration is omitted.

The radio base stations 20-1, 20-2,... Are base stations used in portable radio communication systems. Data collection terminals 10-1, 10-2,... Are wirelessly connected as terminals of the portable wireless communication system. As a communication method of the portable wireless communication system used here, a wireless communication method of a currently used mobile phone, a WiMAX method, an LTE (Long Term Evolution) method, or the like can be used. The present invention is not limited to such a communication method. The configurations of the radio base stations 20-1, 20-2,... Are well known to those skilled in the art and are not directly related to the present invention, and thus detailed configurations thereof are omitted.

The data collection center 30 collects data collected by the data collection terminals 10-1, 10-2,... Via the radio base stations 20-1, 20-2,. Data collection is performed by calling the data collection terminals 10-1, 10-2,... From the data collection center 30 through the radio base stations 20-1, 20-2,. Done.

In the above configuration, the data collection terminals 10-1, 10-2,... Are basically installed in a fixed place, and even if they can move, the movement range is limited to a specific place. Therefore, each of the radio base stations 20-1, 20-2,... Stores direction information 21-1, which stores information about the direction of a specific location where the data collection terminals 10-1, 10-2,. 21-2,... Is configured such that the radio beam forming direction can be controlled so that the radio beam is directed toward the data collection terminals 10-1, 10-2,. Each of the radio base stations 20-1, 20-2,... Communicates with a target data collection terminal among the data collection terminals 10-1, 10-2,. Can do. .. Are actually provided inside the radio base stations 20-1, 20-2,..., But in the figure, for the sake of explanation, the radio base station 20- 1, 20-2,...

[Configuration example of wireless base station]
FIG. 2 is a block diagram showing an example of the configuration of the uplink part for one of the radio base stations 20-1, 20-2,. Hereinafter, this radio base station is indicated by reference numeral 20, and the azimuth memory is indicated by reference numeral 21. Each radio base station 20 includes

reception antennas

31 and 32,

multipliers

33 and 34, an adder 35, and a radio demodulator 36.

Receiving

antennas

31 and 32 receive radio signals transmitted from data collection terminals 10-1, 10-2,. The

multipliers

33 and 34 and the adder 35 constitute a receiving part of the radio beam control means, and based on the information on the direction stored in the direction memory 21, the data collection terminals 10-1 and 10-2. ,... Is controlled so that the radio beam is directed toward a specific terminal. The radio demodulator 36 demodulates the radio signal output from the adder 35 and outputs it as received data.

The formation of the reception radio beam will be described. In the azimuth memory 21, for each of the data collection terminals 10-1, 10-2,..., Complex weights are stored as information regarding the azimuth. The multiplier 33 multiplies the radio signal received by the receiving antenna 31 by the complex weight supplied from the azimuth memory 21. The multiplier 34 multiplies the radio signal received by the receiving antenna 32 by the complex weight supplied from the azimuth memory 21. Adder 35 adds the output signals of

multipliers

33 and 34. Thereby, a reception radio beam is formed and a radio signal from a specific data collection terminal can be received. As a method of forming a reception radio beam, various methods have been proposed by academic societies and others, and any method may be used.

FIG. 3 is a block diagram illustrating a configuration example of the downlink portion of the radio base station 20. The radio base station 20 includes a radio modulator 41,

multipliers

42 and 43, and

transmission antennas

44 and 45.

The wireless modulator 41 modulates transmission data into a wireless signal.

Multipliers

42 and 43 constitute a part for transmission in the radio beam control means, and based on the information on the direction stored in the direction memory 21, of the data collection terminals 10-1, 10-2,. The formation direction of the radio beam is controlled so that the radio beam is directed toward the specific terminal. The transmission antenna 44 transmits a radio signal output from the multiplier 42. The transmission antenna 45 transmits a radio signal output from the multiplier 43.

Explanation of transmission radio beam formation. As described above, the azimuth memory 21 stores complex weights as information regarding the azimuth of each of the data collection terminals 10-1, 10-2,. The multiplier 33 multiplies the radio signal output from the radio modulator 41 by the complex weight supplied from the azimuth memory 21. The multiplier 34 multiplies the radio signal output from the radio modulator 41 by the complex weight supplied from the azimuth memory 21. Thereby, a transmission radio beam is formed, and a radio signal can be transmitted to a specific data collection terminal. As a method of forming a reception radio beam, various methods have been proposed by academic societies and others, and any method may be used.

[Description of effects]
According to the embodiment described above, the following effects can be obtained.

The first effect is that communication is performed by forming a transmission beam in communication between the data collection terminals 10-1, 10-2,... And the radio base stations 20-1, 20-2,. It is possible to reduce interference with other terminals and improve downlink communication quality of other terminals.

The second effect is that communication is performed by forming a reception beam in communication between the data collection terminals 10-1, 10-2,... And the radio base stations 20-1, 20-2,. Since uplink interference from the terminal can be reduced, the transmission power of the data collection terminal can be kept low, or the amount of information that can be communicated with the same transmission power can be increased.

The third effect is that, in communication between the data collection terminals 10-1, 10-2,... And the radio base stations 20-1, 20-2,. That is, the amount of calculation of the weight can be reduced. Since the positions of the data collection terminals 10-1, 10-2,... Are fixed, the data collection terminals 10-1, 10-2,... And the radio base stations 20-1, 20-2,. It is assumed that the communication channel characteristics between and do not vary greatly. Therefore, the transmission / reception weights according to the average channel characteristics between each of the data collection terminals 10-1, 10-2,... And the radio base stations 20-1, 20-2,. -1, 21-2, ... are stored. By using transmission / reception weights stored in the azimuth memories 21-1, 21-2, ..., the data collection terminals 10-1, 10-2, ... and the radio base stations 20-1, 20-2, ... It is not necessary to calculate transmission / reception weights according to the communication channel characteristics between each communication, and the amount of calculation can be reduced. The transmission / reception weights stored in the azimuth memories 21-1, 21-2,... May be calculated after several days or more in consideration of fluctuations in the propagation environment.

FIG. 4 is a block diagram showing another configuration example of the radio base station 20 and shows a configuration example of the uplink part. Here, it is assumed that the data collection terminals 10-1, 10-2,... And the radio base stations 20-1, 20-2,. Each radio base station 20 includes receiving

antennas

31 and 32, multipliers 33-1, 33-2, 34-1 and 34-2, adders 35-1 and 35-2, and a radio demodulator 37. .

When the data collection terminals 10-1, 10-2,... And the radio base stations 20-1, 20-2,... Each have a plurality of transmission / reception antennas, a multi-input / multi-output (MIMO) communication technique is applied. it can. In this case, when the radio base stations 20-1, 20-2,... Perform MIMO communication with each of the data collection terminals 10-1, 10-2,. The transmission / reception matrix of the radio base stations 20-1, 20-2,.

The operation will be described with reference to FIG. Receiving

antennas

31 and 32 receive radio signals transmitted from data collection terminals 10-1, 10-2,. Multipliers 33-1, 33-2, 34-1 and 34-2 multiply the radio signals received by the receiving

antennas

31 and 32 by the transmission / reception matrix (complex matrix) of the azimuth memory 21. Thereby, the multiplexed received signals are separated. Radio demodulator 37 demodulates the radio signals output from adders 35-1 and 35-2, and outputs the demodulation results as received data. Since the configuration example of the downlink part can be easily inferred from the configuration shown in FIG. 4 in correspondence with the description with reference to FIG. 2 and FIG. 3, the description is omitted. By using MIMO communication, the data rate is improved.

FIG. 5 is a block diagram showing a system configuration example when the number of transmission / reception antennas of the radio base station 20 is larger than the number of transmission / reception antennas of the data collection terminals 10-1, 10-2,. In FIG. 5, only one radio base station 20 and direction memory 21 are shown, and the data collection center 30 is not shown.

When the number of transmission / reception antennas of the radio base station 20 is larger than the number of transmission / reception antennas of the data collection terminals 10-1, 10-2,..., MIMO is simultaneously performed with a plurality of data collection terminals 10-1, 10-2,. A multi-user MIMO scheme for performing communication can be applied. In this case, the memory 21 stores not only the transmission / reception weights of the radio base station 20, but also the data collection terminals 10-1, 10-2,... In response to this, multi-user MIMO communication is performed. In order to perform multi-user MIMO communication, a huge amount of computation is required to search for a set of terminals with low mutual interference when performing simultaneous communication. However, as assumed in the present invention, When it can be assumed that the position is fixed and the transmission path characteristics are stable, a set of terminals with low interference can be searched offline.

The present invention has been described above with reference to the embodiments, but the present invention is not limited to the above embodiments. Various changes that can be understood by those skilled in the art can be made to the configuration and details of the present invention within the scope of the present invention.

This application claims priority based on Japanese Patent Application No. 2010-293333 filed on Dec. 28, 2010, the entire disclosure of which is incorporated herein.

10-1, 10-2, ... Data collection terminals 20, 20-1, 20-2, ... Radio base stations 21, 21-1, 21-2, ... Direction memory 30

Data collection center

31, 32 Receiving antenna 33, 33-1, 33-2, 34, 34-1, 34-2 Multiplier 35, 35-1, 35-2

Adder

36, 37 Wireless demodulator

Claims

A data collection terminal that collects predetermined data at a specific location;
A radio base station to which the data collection terminal is wirelessly connected;
With
The radio base station is
An azimuth memory that stores information about the azimuth of the specific location where the data collection terminal is located;
Radio beam control for controlling the formation direction of the radio beam so that the radio beam is directed to the direction of the data collection terminal based on information related to the orientation stored in the orientation memory when communicating with the data collection terminal Means,
A data collection system comprising:
The radio base station is a base station used in a mobile radio communication system,
The data collection system according to claim 1, wherein the data collection terminal is wirelessly connected to the base station as a terminal of the portable wireless communication system.
For a data collection terminal that collects predetermined data at a specific location, an orientation memory that stores information about the orientation of the specific location where the data collection terminal is located;
Radio beam control for controlling the formation direction of the radio beam so that the radio beam is directed to the direction of the data collection terminal based on information related to the orientation stored in the orientation memory when communicating with the data collection terminal Means,
A wireless base station comprising:
The radio base station according to claim 3, wherein the data collection terminal is wirelessly connected as a terminal of a portable radio communication system.
With multiple antennas for multi-input / multi-output multi-antenna communication,
5. The radio base station according to claim 3, wherein matrix information for determining directions of radio beams formed by the plurality of antennas is stored in the azimuth memory as information relating to the azimuth.
The radio base station according to claim 5, wherein the matrix information is stored in the azimuth memory corresponding to each of a plurality of data collection devices.
A wireless base station communication method,
For a data collection terminal that collects predetermined data at a specific location, information on the orientation of the specific location where the data collection terminal is located is stored in the orientation memory;
A communication method for controlling a forming direction of the radio beam so that a radio beam is directed toward the data collection terminal based on information on the direction stored in the direction memory when communicating with the data collection terminal .