JP2012039521A - Multistage relaying radio communication apparatus having outgoing field intensity control feature - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a radio communication apparatus which, even in a bad ambient radio wave environment, realizes radio communication with another radio communication apparatus which is becoming isolated, without degrading the S/N ratio of a received radio wave.SOLUTION: If, after radio wave oscillation by a local radio communication apparatus in bucket relay communication, an ACK from a distant radio communication apparatus cannot be received even when radio wave oscillation is repeated a number of times, upon arrival from a data communication control unit 12 to a radio wave transmission unit 17, the radio field intensity of a radio wave is increased by a prescribed amount by a transmission radio field intensity control unit 18 before being transmitted. Here, if communication fails despite of an increased radio field intensity, radio wave data is stored in memory by an untransmitted data storage unit 19, and in the next local data transmission timing, the data communication control unit loads the data from a local data storage unit 11, a data storage unit 16 in a preceding stage, and the untransmitted data storage unit 19 and increases the field intensity of a radio wave again before transmitting it.

Description

  The present invention relates to a method for relieving a wireless communication device isolated from a wireless communication network due to deterioration of a wireless communication environment in a remote meter reading system using wireless communication.

  A bucket relay system that receives the meter reading data of a meter such as a power meter from the previous stage wireless communication device, adds its own meter reading data and relays it to the next stage wireless communication device, and finally relays it to the meter reading center. There is a wireless communication technique related to a multi-hop method (for example, Patent Document 1).

  However, since the wireless communication device is a wireless communication device installed in a residence, the radio wave environment at the installation location is not always good, and the distance from the preceding or next wireless communication device to be relayed is long In some cases, there has been a problem that a wireless communication device isolated from the bucket relay network leading to the meter reading center occurs.

  In order to improve this problem, the wireless communication device according to the technique described in Patent Document 1 measures the strength of a received radio wave from a wireless communication device existing in the vicinity in advance, and the ID of a wireless communication device capable of communication and the ID thereof. Know the received signal strength in advance. And when the radio wave environment deteriorates, it communicates with the wireless communication device with high received radio wave intensity that is known in advance with normal reception sensitivity, and with the wireless communication device with low received radio wave intensity that is known in advance By increasing the reception sensitivity for communication, the occurrence of isolated wireless communication devices is suppressed.

  However, in the technique described in Patent Document 1, in order to increase the reception sensitivity when the surrounding radio wave environment is bad, the noise component of the received radio wave is increased and the S / N ratio is deteriorated. There was a drawback that it could be repeated.

JP 2008-85583 A

  SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to solve the conventional drawbacks with a wireless communication apparatus that is isolated without degrading the S / N ratio of received radio waves even when the surrounding radio wave environment is bad. It is to realize wireless communication.

  In order to solve the above-described problem, the present invention provides a wireless communication apparatus that relays data from a previous-stage wireless communication apparatus or data collected by the own wireless communication apparatus to a subsequent-stage wireless communication apparatus, and Data receiving means for receiving predetermined data from a communication device by wireless communication, and data received by the data receiving means to another wireless communication device in the next stage and data collected by the own wireless communication device by wireless communication at a predetermined timing Data transmitting means for transmitting, response signal receiving means for receiving a response signal corresponding to the data transmitted by the data transmitting means from another wireless communication device, and radio field intensity for controlling the intensity of the radio wave output by the data transmitting means Control means, and the radio wave intensity control means adds the data to the data within a predetermined time after the data transmission means transmits predetermined data. When the response signal receiving means does not receive a corresponding response signal, the intensity of the radio wave output from the data transmitting means is set to be a value greater than a preset value, and the data transmitting means Retransmits the data to another wireless communication device by wireless communication based on the wireless field strength set by the field strength control means, and retransmits the data with the wireless field strength set to a predetermined maximum value. Nevertheless, if a response signal corresponding to the data is not received from another wireless communication device, the data is stored, and the predetermined data to be transmitted at the transmission timing at the next transmission timing and the storage It is characterized by transmitting previously stored data.

  According to the present invention, even when the surrounding radio wave environment is bad, the intensity of the transmitted radio wave is increased and retransmitted, so that the deterioration of the S / N ratio of the received radio wave on the receiving side can be reduced and the maximum intensity can be achieved. If a transmission error occurs even after retransmission, retransmission is repeated at the next transmission timing after a lapse of a certain time, so that it is possible to provide a wireless communication apparatus that can reliably transmit data to the next stage.

1 is an overall configuration diagram according to an embodiment of the present invention. It is a block block diagram of the radio | wireless communication apparatus which concerns on embodiment of this invention. It is an operation | movement flowchart figure which concerns on embodiment of this invention.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is an overall configuration diagram according to an embodiment of the present invention, and wireless communication apparatuses 1-1 to 1-6 are wireless communication apparatuses of the present invention.

  The wireless communication devices 1-1 to 1-6 store the meter reading data received from the meter reading devices 2-1 to 2-6, communicate with the next-stage wireless communication device, and collect all the meter reading data in the meter reading center 3. It is done. Contrary to the data collection, when the meter reading center 3 designates a data request to the wireless communication device 1-3, the wireless communication device 1-1 can be relayed to communicate with the wireless communication device 1-3. It is. Here, due to the deterioration of the radio wave environment between the wireless communication device 1-1 and the wireless communication device 1-4, the radio wave intensity is weak and communication is impossible, and the wireless communication device 1-4 cannot communicate with other wireless communication devices in the vicinity and is isolated. ing. A configuration and means for enabling an isolated wireless communication terminal to perform normal communication according to the present invention will be described below.

  FIG. 2 is a block configuration diagram of the wireless communication apparatus according to the embodiment of the present invention. The meter reading data received by the wireless communication device 1 from the meter reading device 2 is stored in the own data storage unit 11. When a radio wave is received from the preceding stage, the data communication control unit 12 is reached from the antenna 13 via the RF switch 14 and the radio wave reception unit 15. In order to transmit ACK, a radio wave is transmitted from the antenna 13 via the radio wave transmission unit 17 and the RF switch 14 from the data communication control unit 12. The received data is stored in the previous data storage unit 16.

  When transmitting the own data, the data communication control unit 12 reads the meter reading data from the own data storage unit 11 when the own data transmission timing is set, and reads the meter reading data received from the previous stage from the previous stage data storage unit 16 for transmission. Is performed by the same means as ACK. If the ACK from the partner wireless communication device cannot be received multiple times by radio wave oscillation retry after the radio wave oscillation, when the data communication control unit 12 reaches the radio wave transmission unit 17, the radio wave intensity control unit 18 sets the radio wave intensity. A predetermined value is increased, and radio waves are transmitted from the antenna 13 via the RF switch 14. Here, in the case where communication is not possible despite the increase in radio wave intensity, the data is stored in the untransmitted data storage unit 19 and the data communication control unit and the previous data storage unit 11 and the previous stage are stored at the next own data transmission timing. The data storage unit 16 and the untransmitted data storage unit 19 are read, the radio wave intensity is increased again, and radio waves are transmitted.

  FIG. 3 is an operation flowchart according to the embodiment of the present invention.

  The wireless communication apparatus is powered and starts in a standby state (S100). If the meter reading data has not been received from the previous stage (S110, NO) and the own data transmission timing is not reached (S111, NO), the standby state is repeated. When the meter reading data is received from the previous stage (S110, YES), it is stored in the previous stage data storage unit (S120). The radio wave intensity control unit always monitors the electric field intensity control and returns it to the normal value before entering the standby state (S130).

  When the own data transmission timing comes (S111, YES), the data communication control unit 12 reads the own data storage unit 11 (S140), reads the previous data stored in the previous data storage unit 16 (S141), Untransmitted data stored in the transmission data storage unit 19 is read (S142), transmission data to the next stage is generated, and radio waves are transmitted (S143). When an ACK is received from another wireless communication device within a certain time and during a plurality of retries, the radio wave intensity is returned to the normal value (S130), and the standby state is returned. If ACK is not received within a certain time and during a plurality of retries (S150, NO), the radio wave intensity is increased by a predetermined value and radio wave transmission is performed again (S151). If the electric field strength is not maximum (S152, NO), the predetermined value is increased again. If the electric field strength is maximum (S152, YES), it is stored in the untransmitted data storage unit 19 (S160), and the radio wave intensity is set to the normal value. Return (S130), a standby state is entered.

DESCRIPTION OF SYMBOLS 1 ... Wireless communication apparatus 2 ... Meter-reading apparatus 3 ... Meter-reading center 11 ... Own data storage part 12 ... Data communication control part 13 ... Antenna 14 ... RF switch 15 ... Radio wave receiving unit 16 ... Pre-stage data storage unit 17 ... Radio wave transmission unit 18 ... Transmitted radio wave intensity control unit 19 ... Untransmitted data storage unit

Claims (1)

A wireless communication device that relays data from the previous-stage wireless communication device or data collected by the own wireless communication device to the next-stage wireless communication device,
Data receiving means for receiving predetermined data from another wireless communication apparatus in the previous stage by wireless communication, data received by the data receiving means to the other wireless communication apparatus in the next stage, and data collected by the own wireless communication apparatus at a predetermined timing Data transmitting means for transmitting by wireless communication, response signal receiving means for receiving a response signal corresponding to the data transmitted by the data transmitting means from another wireless communication device, and intensity of the radio wave output by the data transmitting means. Radio wave intensity control means for controlling,
The radio wave intensity control means, when the data transmission means does not receive a response signal corresponding to the data within a predetermined time after the data transmission means transmits predetermined data, the data transmission means Set the intensity of the radio wave output by the to be greater than the preset value,
The data transmission means retransmits the data to another wireless communication device by wireless communication based on the radio wave intensity set by the radio wave intensity control means, and sets the data as the predetermined maximum value of the radio wave intensity. When a response signal corresponding to the data is not received from another wireless communication apparatus despite being retransmitted, the data is stored, and a predetermined signal to be transmitted at the transmission timing at the next transmission timing A multi-stage relay wireless communication apparatus having a function of controlling a transmitted radio wave intensity, wherein the data and the stored data are transmitted.

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