JPH09130373A - Radio communication system - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely perform synchronization correction communication even when communication is interfered. SOLUTION: Upon receiving the output of a timer A4, the frequency switching means A10 of a radio communication A1 selects one frequency other than the frequency selected in a previous time among the frequencies stored in a frequency information storage means A9 and performs the intermittent standby operation of 30 seconds. When the output of the timer B16 is received, the frequency switching means B18 of the radio communication means B2 selects one frequency other than the frequency selected in the previous time among the frequencies stored in the frequency information storage means B17 and performs the intermittent standby operation of 30 seconds. The operation is performed in the synchronization correction communication every ten minutes as well.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless communication system which intermittently performs a synchronization correction operation.

[0002]

2. Description of the Related Art The operation of a conventional wireless communication system will be described with reference to FIG. In FIG. 5, 1 is a wireless communication means A and 2 is a wireless communication means B. Here, it is assumed that the wireless communication means A1 and the wireless communication means B2 constitute a wireless communication system. Reference numeral 3 is a wireless transmission / reception means A for transmitting / receiving a wireless signal. Reference numeral 4 is a timer A that outputs a signal at every predetermined time. Reference numeral 5 is a synchronization correction signal creating means for creating a synchronization correction signal. Reference numeral 6 is a carrier determination means A for confirming the presence or absence of a carrier. Reference numeral 7 is a response signal determining means for determining a response signal. 8 is a counter A that counts a predetermined number of times. Radio transmission / reception means A3, timer A4, synchronization correction signal generation means 5, carrier determination means A6, response signal determination means 7, counter A8
Is inside the wireless communication means A1. Reference numeral 11 is a wireless transmission / reception means B for transmitting / receiving a wireless signal. Reference numeral 12 is a timer B that outputs a signal every predetermined time. Reference numeral 13 is a synchronization correction signal determination means for decoding the content of the received synchronization correction signal. Reference numeral 14 is a response signal creating means for outputting a response signal to the synchronization correction signal. Reference numeral 15 is carrier determination means B for confirming the presence / absence of a carrier. Reference numeral 16 is a counter B that counts a predetermined number of times. Radio transmitting / receiving means B11, timer B12, synchronization correction signal determining means 13, response signal creating means 14, carrier determining means B
15, the counter B16 is inside the wireless communication means B2. Here, a wireless communication system having a plurality of wireless communication means A1 and a plurality of wireless communication means B2 can be considered.

In FIG. 5, the wireless communication means A1 and the wireless communication means B2 enter the first operation mode after the power is turned on. This first mode of operation is called "sleep mode". This "sleep mode" is an ultra-low power consumption operation state in which the power of the wireless unit that performs wireless communication with the wireless communication means on the other side is turned off. From this "sleep mode", the wireless communication means A1 and the wireless communication means B2 are switched to the second
It becomes the operation mode. This second operating mode is called the "initial synchronization mode". This "initial synchronization mode" is a mode in which the initial synchronization correction of the wireless communication between the wireless communication means A1 and the wireless communication means B2 is performed. The wireless communication means A1 transmits an initial synchronization correction signal at a specific frequency at regular time intervals in the "initial synchronization mode". Here, the reason why transmission is performed at regular intervals is to reduce power consumption.

On the other hand, the wireless communication means B2 is in the continuous reception state of a specific frequency in the "initial synchronization mode". When the wireless communication means B2 receives the initial synchronization correction signal sent from the wireless communication means A1 by the wireless transmission / reception means B11, the response signal creation means 14 creates a response signal to the initial synchronization correction signal, and the wireless transmission / reception means B11 wirelessly sends the response signal. After transmitting to the communication means A1, the mode shifts to the third operation mode. This third operation mode is called "data communication mode".

On the other hand, the wireless communication means A1 is the wireless communication means B.
After transmitting the initial synchronization correction signal to No. 2, it waits for a response signal to the initial synchronization correction signal sent from the wireless communication means B2. Then, after the response signal to the initial synchronization correction signal is received by the wireless communication means A3, it shifts to the "data communication mode". In the "data communication mode", the wireless communication means A1 and the wireless communication means B2 operate intermittently.
That is, the wireless communication transmitting / receiving means A1 and the wireless transmitting / receiving means B
In No. 2, the power is turned on only at the time of periodic synchronization correction or when communication is required, and other than that, low power operation is performed.

In this "data communication mode", there are cases in which periodic synchronization correction communication fails.
For example, the wireless transmission / reception unit B cannot normally receive the synchronization correction signal transmitted by the wireless transmission / reception unit A3, or the frequency at which the wireless transmission / reception unit A3 is about to transmit the synchronization correction signal is already used by another system. This is the case when you cannot do it. In this case, the wireless transmission / reception means A3 retransmits the synchronization correction signal at the intermittent reception timing of the next wireless communication means B2.

Next, the operation in each mode of such a wireless communication system will be described more specifically. In FIG. 5, the wireless communication means A1 and the wireless communication means B2 enter the "sleep mode" after the power is turned on. From the "sleep mode", the wireless communication means A1 and the wireless communication means B2 are switched to the "initial synchronization mode" by a switch or the like. This is an operation of performing the first synchronization (synchronization correction) because the wireless communication means A1 and the wireless communication means B2 are not yet synchronized with each other. The wireless communication means A1 activates the timer A4 after the operation is restored. The timer A4 measures a predetermined time and outputs a signal to that effect each time the measurement is completed. Here, the predetermined time is 5 seconds.

The carrier determining means A6 receives the signal output from the timer A4 and checks whether or not a specific frequency with which communication is to be performed is being used by another system. That is, it is checked whether or not there is a radio wave having a frequency for communication. This is called "carrier sense". The carrier determination means A6 outputs the result of "carrier sense". The wireless transmission / reception unit A3 transmits the initial synchronization correction signal stored in the synchronization correction signal generation unit 5 from the antenna when the carrier determination unit A6 outputs a signal indicating "no radio wave". After sending
The wireless transmission / reception means A3 shifts to a reception state for receiving a response signal to the synchronization correction signal from the other party. At this time, the carrier determining means A6 checks by "carrier sense" whether the response signal to the synchronization correction signal is transmitted from the other party. As a result of the "carrier sense", when the carrier determination means A6 determines "there is a radio wave", the wireless transmission / reception means A3 receives the response signal to the synchronization correction signal and outputs the received data to the response signal determination means 7.
The response signal judging means 7 analyzes the received data and judges whether it is correct or not. If the received data is correct, the response signal determination means 7 outputs a signal to that effect. Then, the wireless communication means A1 ends the "initial synchronization mode" with the signal and shifts to the "data communication mode". At this time, the wireless communication means A1 changes the measurement time of the timer A4 from 5 seconds to another time.

Here, the other time is 10 minutes. When the carrier determination unit A6 cannot transmit the initial synchronization correction signal because it has determined that there is a radio wave in the "carrier sense" before the transmission of the initial synchronization correction signal, the carrier determination unit A6 receives the response signal to the initial synchronization correction signal. When it is determined that there is no radio wave in the "carrier sense" of step 1, and when the response signal determination unit 7 determines that the received data is not a response signal to the correct initial synchronization correction signal, the initial synchronization correction operation is repeated again. That is, a series of operations from "carrier sense" is repeated in response to the signal output by the timer A4 every 5 seconds. If the initial synchronization correction operation does not end normally even if the timer A4 measures and outputs a signal a predetermined number of times or more, the operation returns to the "sleep mode".

Next, the "initial synchronization mode" of the wireless communication means B2 will be described. After the operation is restored, the wireless communication means B2 puts the wireless transmission / reception means B11 into a continuous reception state at a specific frequency, that is, the other side, that is, the wireless communication means A
The system is ready to receive the initial synchronization correction signal sent from 1. That is, the carrier determination unit B15 continuously performs “carrier sense”, and when the “carrier sense” determines that “radio wave is present”, the wireless transmission / reception unit B11 receives the initial synchronization correction signal. Upon receiving the initial synchronization correction signal, the wireless transmission / reception means B11 outputs the received data to the synchronization correction signal determination means 13. The synchronization correction signal determination means 13 analyzes whether the received data is correct.

If it is correct, the measurement start value of the timer B12 is corrected according to the synchronization correction signal. Then, the response signal creation means 14 creates a response signal to the synchronization correction signal including the result analyzed by the synchronization correction signal determination means 13 and transmits it from the wireless transmission / reception means B11. When the synchronization correction signal determination unit 13 determines that the initial synchronization correction signal received by the wireless transmission / reception unit B11 is correct, the wireless communication unit B2 terminates the “initial synchronization mode” after transmitting a response signal to the synchronization correction signal and ends the “data communication”. Then, the timer B12 is started. The timer B12 starts measuring a predetermined time. It is assumed that this predetermined time is equal to the time measured by the timer A of the wireless communication means A1 after the completion of the initial synchronization correction, and here it is set to 10 minutes.

When the synchronization correction signal determination means 13 determines that the initial synchronization correction signal received by the wireless transmission / reception means B11 is not correct, the wireless communication means B2 again performs continuous reception operation after transmitting a response signal to the initial synchronization correction signal, and wireless communication is performed. It waits for the next initial synchronization correction signal sent from the means A1.
If the initial synchronization correction signal does not end normally even if the continuous reception operation is performed for a predetermined time or more, the operation returns to the "sleep mode".

Next, the "data communication mode" after the "initial synchronization mode" is completed will be described. Here, in the intermittent operation, the wireless communication means A1 and the wireless communication means B2 shift to the reception standby operation every 30 seconds, and the synchronization correction is performed every 10 minutes. At the timing of synchronization correction, the timer A4 of the wireless communication means A1 repeatedly measures 10 minutes and outputs a signal to that effect each time the measurement is completed. The carrier determination means A6 receives the signal output by the timer A4, performs "carrier sense", and outputs the result. The wireless transmission / reception unit A3 transmits the synchronization correction signal created by the synchronization correction signal creation unit 5 from the antenna at a specific frequency when the carrier determination unit A6 outputs a signal indicating "no radio wave". After transmission, the wireless transmission / reception means A1 shifts to a reception state for receiving a response signal to the synchronization correction signal from the other party.

At this time, the carrier determining means A6 checks by "carrier sense" whether the response signal to the synchronization correction signal is transmitted from the other party. As a result of the "carrier sense", when the carrier determination means A6 determines "there is a radio wave", the wireless transmission / reception means A3 receives the response signal to the synchronization correction signal and outputs the received data to the response signal determination means 7. The response signal judging means 7 analyzes the received data and judges whether it is correct or not. If the received data is correct, the response signal determination means 7 outputs a signal to that effect. The wireless communication means A1 ends the wireless communication operation based on the signal, resets the counter A8, and waits for the output of the next timer A4 to finish the measurement. When the carrier determination unit A6 cannot transmit the synchronization correction signal because it has determined that "the radio wave is present" in the "carrier sense" before the synchronization correction signal is transmitted, the carrier determination unit A6 receives the "carrier" before the response signal to the synchronization correction signal is received. When it is determined that "no radio wave" in the "sense", and the response signal determination unit 7 determines that the received data is not the response signal to the correct synchronization correction signal,
The carrier determination means A6 and the response signal determination means 7 output a signal to that effect to the counter A8, and at the same time, the synchronization correction signal at the same specific frequency as the other party, that is, the intermittent reception timing of 30 seconds of the wireless communication means B2. Resend. The retransmission operation is the same as the original synchronization correction signal transmission operation. If the synchronization correction communication does not end normally even if the counter A8 counts a predetermined number of times, the wireless communication means A1 is in the "sleep mode".
Return to

Next, the "data communication mode" of the wireless communication means B2 will be described. After the end of the initial synchronization correction, the timer B16 in the wireless communication means B2 repeatedly measures 30 seconds or 10 minutes. The timer B16 outputs a signal to that effect every time measurement of 10 minutes is completed. Upon receiving the output signal of the timer B16, the carrier determination means B15 performs "carrier sense". When this "carrier sense" determines that "there is a radio wave", the wireless transmission / reception means B11 shifts to the reception state and receives the synchronization correction signal from the other side, that is, the wireless communication means A1. Upon receiving the synchronization correction signal, the wireless transmission / reception means B11 outputs the received data to the synchronization correction signal determination means 13. The synchronization correction signal determination means 13 analyzes whether the received data is correct. If it is correct, the measurement start value of the timer B12 is corrected according to the synchronization correction signal. Then, the response signal creation means 14 creates a response signal to the synchronization correction signal including the result analyzed by the synchronization correction signal determination means 13 and transmits it from the wireless transmission / reception means B11. When the synchronization correction signal determination unit 13 determines that the synchronization correction signal received by the wireless transmission / reception unit B11 is correct, the wireless communication unit B2 resets the counter B16, ends the wireless communication operation, and outputs the measurement end of the next timer B12. I'll be waiting. Even when the synchronization correction signal determination means 13 determines that the synchronization correction signal received by the wireless transmission / reception means B11 is incorrect, the wireless communication means B2 operates intermittently after transmitting a response signal to the synchronization correction signal.

On the other hand, the synchronization correction signal determination means 13 outputs a signal to that effect when the synchronization correction signal received by the wireless transmission / reception means B11 is not correct or when the wireless transmission / reception means B11 cannot receive the synchronization correction signal. . Also, the carrier determination unit B15 also outputs a signal to that effect when it determines "no radio wave" in "carrier sense" at the synchronization correction timing every 10 minutes. In such a case, the wireless communication means B2 waits for the synchronization correction retransmission signal that should be sent from the wireless communication means A1 at the next 30 seconds intermittent reception timing at the same specific frequency as before. This receiving operation is the same as the case of the regular synchronization correction timing every 10 minutes. The counter B16 is provided with a signal output by the synchronization correction signal determination means 13 when the synchronization correction signal received by the wireless transmission / reception means B11 is incorrect, or when the wireless transmission / reception means B11 cannot receive the synchronization correction signal, and the carrier determination means B15. When the signal output when "no radio wave" is determined by "carrier sense" at the synchronization correction timing every 10 minutes is received, the number of times is counted. Then, if the synchronization correction communication does not end normally even if the counter B16 counts a predetermined number of times, the wireless communication means B2 returns to the "sleep mode".

[0017]

However, the above-mentioned conventional configuration has a problem when an interfering signal exists at a specific frequency. That is, the wireless communication means A1 and the wireless communication means B2 perform synchronization correction communication and retransmit at a certain specific frequency. Then, if interference of "carrier sense level" or more occurs at this frequency due to jamming radio waves from other systems or environmental noise, there is a problem that even if retransmitting communication is performed, synchronization correction will not succeed and the wireless communication system will not be established. there were.

The present invention has been made to solve the above-mentioned problems, and an object of the present invention is to reliably perform synchronization correction communication even when communication is disturbed.

[0019]

The wireless communication system of the present invention performs intermittent synchronization correction communication at predetermined time intervals. Therefore, in the wireless communication system in which the power supply is opened / closed, the intermittent operation is performed. A is a signal transmitting means A for transmitting a synchronization correction signal or a data communication signal to the wireless communication means B, a signal receiving means A for receiving a data communication signal from the wireless communication means B, the signal transmitting means A and the signal. The wireless communication means B has a frequency switching means A for switching the operating frequency of the receiving means A, the wireless communication means B transmits a data communication signal to the wireless communication means A, and a synchronization correction signal from the wireless communication means A. Alternatively, the signal receiving means B for receiving the data communication signal and the signal transmitting means B
And frequency switching means B for switching the operating frequency of the signal receiving means B.

According to the present invention, loss of synchronization and unsuccessful data communication can be prevented, and reliability is further improved.

[0021]

BEST MODE FOR CARRYING OUT THE INVENTION In order to achieve the above object, the wireless communication system of the present invention turns on the power of the wireless communication unit at predetermined time intervals to perform data communication or intermittent synchronization correction communication to obtain data. In a wireless communication system composed of at least one wireless communication means A and at least one wireless communication means B that perform an intermittent operation of cutting off the power source of the wireless communication unit at the time of completion of communication or synchronization correction communication The wireless communication means A transmits a synchronization correction signal or a data communication signal to the wireless communication means B, a signal receiving means A receives a data communication signal from the wireless communication means B, and the signal. It has frequency switching means A for switching the operating frequencies of the transmitting means A and the signal receiving means A, and the wireless communication means B sends a data communication signal to the wireless communication. A signal transmitting means B to be transmitted to the stage A,
A signal receiving means B for receiving a synchronization correction signal or a data communication signal from the wireless communication means A, and a frequency switching means B for switching the operating frequencies of the signal transmitting means B and the signal receiving means B are provided.

Further, the frequency switching means A has a frequency information storage means A for storing a plurality of frequency information and a predetermined pattern among the plurality of frequency information stored in the frequency information storage means A. Frequency information selecting means A for selecting and outputting one frequency information in synchronization with the intermittent cycle, and communication frequency determining means for determining the communication frequency of synchronization correction communication and data communication based on the frequency information output by the frequency information selecting means A. A frequency switching means B having A is stored in the frequency information storage means B for storing a plurality of the frequency information and a plurality of frequency information stored in the frequency information storage means B. The frequency information selecting means B for selecting and outputting one frequency information in synchronization with the intermittent cycle according to the pattern, and the frequency information selecting means B for outputting. Communication frequency determining means B for determining a synchronization correction and data communications in a communication frequency by the frequency information
It is provided with.

Further, the frequency switching means A synchronizes a frequency information storage means for storing a plurality of frequency information and one of the plurality of frequency information stored in the frequency information storage means with an intermittent cycle. The frequency information selecting means for selecting and outputting the frequency information, the signal generating means for generating the synchronization correction signal or the data communication signal including the frequency information output by the frequency information selecting means, and the frequency information outputting by the frequency information selecting means for synchronization. It has a communication frequency deciding means A for deciding the communication frequency of correction communication and data communication, and the frequency switching means B analyzes the frequency information sent from the wireless communication means A, and the signal analyzing means analyzes it. The communication frequency determining means B for determining the communication frequency of the synchronization correction communication and the data communication based on the frequency information is provided.

According to the present invention, the frequency for performing synchronization correction communication is switched by the above configuration.

Further, a plurality of frequencies for performing the synchronization correction communication are stored in advance on both sides, and the synchronization correction communication is performed at one of the stored frequencies.

Further, a plurality of frequencies for performing the synchronization correction communication are stored in advance by the side transmitting the synchronization correction signal, and the synchronization correction communication is performed at the switched frequency by transmitting the information of the frequency to the other side. Is.

An embodiment of the present invention will be described below with reference to FIG. In FIG. 1, 1 is a wireless communication means A and 2 is a wireless communication means B. Here, it is assumed that the wireless communication means A1 and the wireless communication means B2 constitute a wireless communication system. Reference numeral 3 is a wireless transmission / reception means A for transmitting / receiving a wireless signal. Reference numeral 4 is a timer A that outputs a signal at every predetermined time. Reference numeral 5 is a synchronization correction signal creating means for creating a synchronization correction signal. Reference numeral 6 is a carrier determination means A for confirming the presence or absence of a carrier. Reference numeral 7 is a response signal determining means for determining a response signal. 8 is a counter A that counts a predetermined number of times. Reference numeral 9 is a frequency information storage means A in which frequency information is stored. Reference numeral 10 is frequency switching means A for switching the synchronization correction signal transmission frequency. The wireless transmission / reception means A3, the timer A4, the synchronization correction signal generation means 5, the carrier determination means A6, the response signal determination means 7, the counter A8, the frequency information storage means A9, and the frequency switching means A10 are inside the wireless communication means A2. Reference numeral 11 is a wireless transmission / reception means B for transmitting / receiving a wireless signal. 12
Is a timer B that outputs a signal every predetermined time. Reference numeral 13 is a synchronization correction signal determination means for decoding the content of the received synchronization correction signal. Reference numeral 14 is a response signal creating means for outputting a response signal to the synchronization correction signal. Reference numeral 15 is carrier determination means B for confirming the presence or absence of a carrier.
16 is a counter B that counts a predetermined number of times
It is. Reference numeral 17 is frequency information storage means B in which frequency information is stored. Reference numeral 18 denotes frequency switching means B for switching the synchronization correction signal reception frequency. Wireless transmission / reception means B
11, the timer B12, the synchronization correction signal determination means 13, the response signal creation means 14, the carrier determination means B15, the counter B16, the frequency information storage means B17, and the frequency switching means B18 are inside the wireless communication means B2. Here, a wireless communication system having a plurality of wireless communication means A1 and a plurality of wireless communication means B2 can be considered.

In each mode of such a wireless communication system
The operation will be described with reference to FIG. In FIG. 1, wireless communication
After the power is turned on, the means A1 and the wireless communication means B2
It becomes the "poop mode". In this "sleep mode"
Does not have wireless communication means A1 and wireless communication means B2.
The power of the line communication unit is turned off and the line communication unit operates with an extremely low current consumption.
Here, frequency information storage means A9, frequency information storage means
Some frequency information is stored in B17. example
For example, if the frequency used in this wireless communication system is f ₀~ F_Four
And the frequency information storage means A9 and the frequency.
F is stored in the number information storage means B17.₀~ F_FiveUp to 5
Frequency information is stored. And those 5 frequencies
Select one frequency from the information. Here this
Frequency is f ₀And

From the "sleep mode", the wireless communication means A1 and the wireless communication means B2 are switched to the "initial synchronization mode" by a switch or the like. This is an operation of performing the first synchronization (synchronization correction) because the wireless communication means A1 and the wireless communication means B2 are not yet synchronized with each other.
The wireless communication means A1 activates the timer A4 after the operation is restored. The timer A4 measures a predetermined time and outputs a signal to that effect each time the measurement is completed. Here, the predetermined time is 5 seconds. The carrier determining means A6 receives the signal output from the timer A4 and checks whether the frequency: f _{0 at} which the first synchronization correction communication is performed is used by another system. That is, the frequency for performing synchronization correction communication:
Examine the presence or absence of radio waves at f ₀ . This is "career sense"
That. The carrier determining means A outputs the result of "carrier sense". The wireless transmission / reception means A3 outputs the initial synchronization correction signal stored in the synchronization correction signal generation means 5 when the carrier determination means A6 outputs a signal indicating "no radio wave".
Transmit from the antenna at a frequency of ₀ . After the transmission, the wireless transmission / reception means A3 shifts to a reception state for receiving a response signal to the synchronization correction signal from the other party. Communication of a response signal to this synchronization correction signal is also performed at f ₀ .

At this time, the carrier determining means A6 checks whether or not the response signal to the synchronization correction signal is transmitted from the other side by "carrier sense" of frequency: f ₀ . As a result of the "carrier sense", when the carrier determining means A6 determines that "f ₀ " is "radio wave", the wireless transmitting / receiving means A3 receives the response signal to the synchronization correction signal and outputs the received data to the response signal determining means 7. . Response signal determination means 7
Analyzes the received data and determines whether it is correct. If the received data is correct, the response signal determination means 7 outputs a signal to that effect. Then, the wireless communication means A3 ends the "initial synchronization mode" with the signal and shifts to the "data communication mode". At this time, the wireless communication means A3 changes the measurement time of the timer A4 from 5 seconds to another time.

Here, the other time is 10 minutes. When the carrier determination unit A6 cannot transmit the initial synchronization correction signal when it determines that "there is a radio wave" in "carrier sense" of f ₀ before transmitting the initial synchronization correction signal, the carrier determination unit A
If 6 determines that there is no radio wave in the “carrier sense” of f ₀ before receiving the initial synchronization correction response signal, the response signal determination unit 7 determines that the received data is not the correct initial synchronization correction response signal. The synchronization correction operation is repeated again.
That is, a series of operations from "carrier sense" is repeated in response to the signal output by the timer A4 every 5 seconds. The transmission frequency in this repetitive operation is f ₀ . If the initial synchronization correction operation does not end normally even if the timer A4 measures and outputs a signal a predetermined number of times or more, the operation returns to the "sleep mode".

Next, the "initial synchronization mode" of the wireless communication means B2 will be described. Wireless communication means B2 is synchronization correction frequency operation after returning the wireless transceiver means B11: in the continuous reception state in f ₀ counterpart, that is, the receiving system of the initial synchronization correction signal transmitted f ₀ from the wireless communication unit A1. That is, the carrier determination means B15 continuously f
_When “carrier sense” of ₀ is performed and it is determined by “carrier sense” that “radio wave exists”, the wireless transmission / reception means B11 receives the initial synchronization correction signal. Upon receiving the initial synchronization correction signal, the wireless transmission / reception means B11 outputs the received data to the synchronization correction signal determination means 13. The synchronization correction signal determination means 13 analyzes whether the received data is correct.

If it is correct, the measurement start value of the timer B12 is corrected according to the synchronization correction signal. Then, the response signal creation means 14 creates a response signal to the synchronization correction signal including the result analyzed by the synchronization correction signal determination means 13 and transmits it from the wireless transmission / reception means B11. When the synchronization correction signal determination means 13 determines that the initial synchronization correction signal received by the wireless transmission / reception means B11 is correct, the wireless communication means B2 transmits a response signal to the synchronization correction signal at f ₀ and ends the “initial synchronization mode”. Then, the mode shifts to the "data communication mode" and the timer B12 is started. Timer B12
Starts the measurement for a predetermined time. It is assumed that this predetermined time is equal to the time measured by the timer A4 of the wireless communication means A1 after the completion of the initial synchronization correction, and here, 1
0 minutes. If the synchronization correction signal determining means 13 determines that the initial synchronization correction signals received by the wireless transceiver means B11 is not correct, the wireless communication unit B11 is continuously receiving a response signal in response to the initial synchronizing the correction signal at f ₀ again after transmission at f ₀ The operation starts and waits for the next initial synchronization correction signal sent from the wireless communication means A1. When the initial synchronization correction signal does not end normally even if the continuous reception operation is performed at f ₀ for a predetermined time or more, the operation returns to the “sleep mode”.

Next, the "data communication mode" after the "initial synchronization mode" is completed will be described. Here, in the intermittent operation, it is assumed that the wireless communication means A1 and the wireless communication means B2 shift to the reception waiting operation at f ₀ every 30 seconds, and the synchronization correction is performed every 10 minutes. The timer A4 performs the measurement for 30 seconds or 10 minutes. The timer A4 outputs a signal to that effect every time 30 seconds or 10 minutes have been measured. The frequency switching means A10 is a timer A
When the output of 4 is received, of the five frequencies f _{0 to} f ₄ stored in the frequency information storage means A9, the previously selected 1
One frequency other than the two frequencies (f _{0 in} this case) is selected. Here, the frequency is set to f ₁ . And
At this f ₁ , an intermittent standby operation is performed for 30 seconds. This intermittent waiting operation is an operation for checking whether there is communication from the other party, that is, the wireless communication means A1, and if "carrier sense" is performed and it is determined that "radio wave", it shifts to a signal receiving operation. When it is determined by "carrier sense" that "no radio wave", the operation of the wireless unit is stopped and the low power consumption operation is performed, and the output of the next timer A4 after 30 seconds has elapsed is waited for. And
When the next output of the timer A4 is received, the frequency switching means A10 switches the frequency similarly to the previous time. Then, after the frequency is once used from f _{0 to} f ₄ , the same frequency switching is performed again from f ₀ .

When the synchronization correction timing is reached for 10 minutes by repeating such an operation, the carrier determining means A6 receives a signal indicating that 10 minutes has elapsed, which is output from the timer A4, and performs "carrier sense" at the frequency at that time. Perform and output the result. Let the frequency at this time be f ₀ . Radio transceiver means A3 transmits a synchronization correction signal generated by the synchronization correction signal generating means 5 when the carrier determination unit A6 has output signal indicating that the "no wave" in f ₀ at f ₀ from the antenna. After the transmission, the wireless transmission / reception means A3 shifts to a reception state for receiving a response signal to the synchronization correction signal from the other party. At this time, if the carrier determination unit A6 is a response signal to the synchronization correction signal is transmitted from the counterpart f ₀
Find out by "career sense". As a result of "carrier sense", the carrier determination means A6 has "radio wave" at f ₀
When it is determined that the wireless transmission / reception unit A3 receives the response signal to the synchronization correction signal, the wireless transmission / reception unit A3 outputs the received data to the response signal determination unit 7. The response signal judging means 7 analyzes the received data and judges whether it is correct or not.

If the received data is correct, the response signal determination means 7 outputs a signal to that effect. The wireless communication means A1 ends the wireless communication operation based on the signal, and the counter A
8 is reset, and the output of the next measurement of the timer A4 is awaited. If the carrier determination unit A6 cannot transmit the synchronization correction signal because it has determined that there is a radio wave in the "carrier sense" of f ₀ before transmitting the synchronization correction signal, the carrier determination unit A6 receives the response signal to the synchronization correction signal. When it is determined that there is no radio wave in the "carrier sense" of f ₀ , when the response signal determination means 7 determines that the received data is not a response signal to the correct synchronization correction signal, the carrier determination means A8 and the response signal determination means 7 outputs a signal to that effect to the counter A8 and retransmits the synchronization correction signal at the intermittent reception timing of the other party, that is, the wireless communication means B2 for the next 30 seconds. The frequency at this time is the frequency switched by the frequency switching means A10, and is f ₁ in this case. The retransmission operation is the same as the original synchronization correction signal transmission operation. Then, if the synchronization correction communication does not end normally even if the counter A8 counts a predetermined number of times, the wireless communication means A1 returns to the "sleep mode".

Next, the "data communication mode" of the wireless communication means B2 will be described. After the completion of the initial synchronization correction, the timer B12 in the wireless communication means B2 repeatedly measures 30 seconds or 10 minutes. Then, each time the measurement is completed, a signal to that effect is output. When the frequency switching means B18 receives the output of the timer B16, the frequency information storage means B17
Among the five frequencies f _{0 to} f ₄ stored in, the frequency other than the one selected previously (f _{0 in} this case) is selected. Here, the frequency is set to f ₁ . Then, the intermittent standby operation for 30 seconds is performed at this f ₁ . This intermittent waiting operation is an operation for checking whether there is communication from the other party, that is, the wireless communication means A1, and if "carrier sense" is performed and it is determined that "radio wave", it shifts to a signal receiving operation. When it is determined by "carrier sense" that "no radio wave", the operation of the wireless unit is stopped and the low power consumption operation is performed, and the next timer B16 waits for the output when 30 seconds have elapsed. Then, when the next output of the timer B16 is received, the frequency switching means B18 switches the frequency as in the previous time. Then, after the frequency is once used from f _{0 to} f ₄ , the same frequency switching is performed again from f ₀ .

When the above-described operation is repeated and the synchronization correction timing reaches 10 minutes, the carrier determination means B15
Receives the output signal of the timer B12 indicating that 10 minutes have elapsed, and performs "carrier sense" at the frequency at that time. Let the frequency at this time be f ₀ . When it is determined that there is a radio wave in this "carrier sense" of f ₀ , the wireless transmission / reception means B
11 shifts to the receiving state and is sent from the other side, that is, the wireless communication means A1 at f ₀ . Receive a synchronization correction signal. Upon receiving the synchronization correction signal, the wireless transmission / reception means B11 outputs the received data to the synchronization correction signal determination means 13. The synchronization correction signal determination means 13 analyzes whether the received data is correct. If it is correct, the measurement start value of the timer B12 is corrected according to the synchronization correction signal. Then, the response signal creating means 14 is the synchronization correction signal determining means 1
A response signal to the synchronization correction signal including the analysis result of 3 is created and transmitted from the wireless transmission / reception means B11 at f ₀ .
When the synchronization correction signal determination unit 13 determines that the synchronization correction signal received by the wireless transmission / reception unit B11 is correct, the wireless communication unit B2 resets the counter B16, ends the wireless communication operation, and outputs the measurement end of the next timer B12. I'll be waiting. Even when the synchronization correction signal determination means 13 determines that the synchronization correction signal received by the wireless transmission / reception means B11 is not correct, the wireless communication means B2 operates intermittently after transmitting a response signal to the synchronization correction signal at f ₀ .

On the other hand, the synchronization correction signal determination means 13 outputs a signal to that effect when the synchronization correction signal received by the wireless transmission / reception means B11 is not correct or when the wireless transmission / reception means B11 cannot receive the synchronization correction signal. . Also, the carrier determination means B15 also outputs a signal to that effect when it determines "no radio wave" in "carrier sense" of f ₀ at the synchronization correction timing every 10 minutes. In such a case, the wireless communication unit B2 waits for the synchronization correction retransmission signal that should be sent from the wireless communication unit A1 at the next 30 seconds intermittent reception timing at the frequency switched by the frequency switching unit B18. In the case of this example, it is f ₁ . This receiving operation is the same as the case of the regular synchronization correction timing every 10 minutes. The counter B16 is provided with a signal output by the synchronization correction signal determination means 13 when the synchronization correction signal received by the wireless transmission / reception means B11 is incorrect, or when the wireless transmission / reception means B11 cannot receive the synchronization correction signal, and the carrier determination means B15. When the signal output when "no radio wave" is determined by "carrier sense" at the synchronization correction timing every 10 minutes is received, the number of times is counted.
Then, if the synchronization correction communication does not end normally even if the counter B16 counts a predetermined number of times, the wireless communication means B2 returns to the "sleep mode". FIG. 2 shows the operation timing of the wireless communication means A1 and B2 in the "data communication mode". As can be seen from FIG. 2, it is necessary that the frequency switching means A10 and the frequency switching means B18 have the same cyclic pattern of frequencies to be switched.

Note that the wireless communication means A1 and the wireless communication means B2 perform similar frequency switching for communication even during normal data communication other than synchronization correction communication.

Various methods are conceivable as the method of selecting the traveling pattern. For example, a method of determining a cyclic pattern from a calling code given to each device in a specific low power wireless communication system is also conceivable. In any case,
Considering the case where this wireless communication system has spread widely and generally, it is less likely that radio waves will collide if the cyclic pattern is changed in each set.

On the other hand, a method may be considered in which the cyclic pattern is not determined in advance. An example of the operation of the wireless communication means A1 and the wireless communication means B2 in the "data communication mode" in this case will be described with reference to FIG.

In FIG. 3, reference numeral 1 is a wireless communication means A. Reference numeral 2 is a wireless communication means B. Here, it is assumed that the wireless communication means A1 and the wireless communication means B2 constitute a wireless communication system. Reference numeral 3 is a wireless transmission / reception means A for transmitting / receiving a wireless signal. Reference numeral 4 is a timer A that outputs a signal at every predetermined time. Reference numeral 5 is a synchronization correction signal creating means for creating a synchronization correction signal. Reference numeral 6 is a carrier determination means A for confirming the presence or absence of a carrier. Reference numeral 7 is a response signal determining means for determining a response signal. 8 is a counter A that counts a predetermined number of times. Reference numeral 10 is frequency switching means A for switching the synchronization correction signal transmission frequency. Reference numeral 19 is a retransmission number counting means for counting the number of retransmissions. Radio transmitting / receiving means A3, timer A4, synchronization correction signal generating means 5, carrier determining means A6, response signal determining means 7, counter A8, frequency switching means 10,
The retransmission number counting means 19 is inside the wireless communication means A2. Reference numeral 11 is a wireless transmission / reception means B for transmitting / receiving a wireless signal.
It is. Reference numeral 12 is a timer B that outputs a signal every predetermined time. Reference numeral 13 is a synchronization correction signal determination means for decoding the content of the received synchronization correction signal. Reference numeral 14 is a response signal creating means for outputting a response signal to the synchronization correction signal. Reference numeral 15 is carrier determination means B for confirming the presence / absence of a carrier. Reference numeral 16 is a counter B that counts a predetermined number of times. Reference numeral 18 denotes frequency switching means B for switching the synchronization correction signal reception frequency. Wireless transmission / reception means B11, timer B12, synchronization correction signal determination means 1
3, response signal creation means 14, carrier determination means B15,
The counter B16 and the frequency switching means B18 are inside the wireless communication means B2. Here, a wireless communication system having a plurality of wireless communication means A1 and a plurality of wireless communication means B2 can be considered.

In FIG. 3, "initial synchronization mode"
The "data communication mode" after the end will be described. Here, the intermittent operation is performed every 30 seconds by the wireless communication means A1.
Then, the wireless communication means B2 shifts to the reception standby operation at f ₀ and performs synchronization correction every 10 minutes. The timer A4 performs the measurement for 30 seconds or 10 minutes.
The timer A4 outputs a signal to that effect every time 30 seconds or 10 minutes have been measured. Upon receiving the output of the timer A4, the frequency switching means A10 selects one frequency (f _{0 in} this case) from the five frequencies f _{0 to} f ₄ stored in the frequency information storage means A9. And this f ₀
Performs an intermittent standby operation for 30 seconds. This intermittent waiting operation is an operation for checking whether there is communication from the other party, that is, the wireless communication means A1, and if "carrier sense" is performed and it is determined that "radio wave", it shifts to a signal receiving operation. When it is determined by "carrier sense" that "no radio wave", the operation of the wireless unit is stopped and the low power consumption operation is performed, and the output of the next timer A4 after 30 seconds has elapsed is waited for. When such operation is repeated and the synchronization correction timing reaches 10 minutes, the carrier determination means A6 receives a signal indicating that 10 minutes has elapsed from the timer A4, performs "carrier sense" at f ₀ , and outputs the result. Output. Radio transceiver means A3 transmits a synchronization correction signal generated by the synchronization correction signal generating means 5 when the carrier determination unit A6 has output signal indicating that the "no wave" in f ₀ at f ₀ from the antenna. After the transmission, the wireless transmission / reception means A3 shifts to a reception state for receiving a response signal to the synchronization correction signal from the other party.

At this time, the carrier determining means A6 checks whether or not the response signal to the synchronization correction signal is transmitted from the other side by "carrier sense" of f ₀ . As a result of the "carrier sense", when the carrier determining means A6 determines that "f ₀ " is "radio wave", the wireless transmitting / receiving means A3 receives the response signal to the synchronization correction signal and outputs the received data to the response signal determining means 7. . The response signal judging means 7 analyzes the received data and judges whether it is correct or not. If the received data is correct, the response signal determination means 7 outputs a signal to that effect. The wireless communication means A1 ends the wireless communication operation based on the signal, resets the counter A8, and waits for the output of the next timer A4 to finish the measurement. If the carrier determination unit A6 cannot transmit the synchronization correction signal because it has determined that there is a radio wave in the "carrier sense" of f ₀ before transmitting the synchronization correction signal, the carrier determination unit A6 receives the response signal to the synchronization correction signal. When it is determined that there is no radio wave in the "carrier sense" of f ₀ , when the response signal determination means 7 determines that the received data is not a response signal to the correct synchronization correction signal, the carrier determination means A8 and the response signal determination means 7 outputs a signal indicating the counter A8 and retransmission count counting means 19, retransmits counterpart, i.e. the synchronization correction signal to the intermittent reception timing of the next 30 seconds of the wireless communication means B2 at f _0. And
If the synchronization correction communication does not end normally even if the counter A8 counts a predetermined number of times, the wireless communication means A1 returns to the "sleep mode". Here, the retransmission number counting unit 19 counts the number of retransmissions for each frequency when the wireless communication unit A1 shifts to the retransmission operation. That is, in this case, the number of retransmissions of f ₀ is incremented. Then, a frequency with the smallest number of retransmissions is selected from the number of retransmissions of each of the five frequencies (f _{0 to} f ₄ ) and a signal indicating that is output.

For example, the number of retransmissions of each frequency is f
₀Twice, f₁5 times, f_Two0 times, f_ThreeOnce, f_FourIs 3
Suppose it was a time. At this time, f_Two2 times is the least
Therefore, the retransmission number counting means 19 outputs a signal to that effect.
You. The wireless transmission / reception means A2 is f ₀Retransmit the sync correction signal with
The information output by the resending count counting means 19 is
And resend. Synchronization correction communication with this resend ended normally
In this case, the frequency switching means A10 will wait 30 seconds.
The frequency during reception and synchronization correction communication is f₀To f_TwoCut into pieces
Replace. That is, the wireless communication means A1
Change frequency only.

Next, the "data communication mode" of the wireless communication means B2 will be described. After the completion of the initial synchronization correction, the timer B12 in the wireless communication means B2 repeatedly measures 30 seconds or 10 minutes. Then, each time the measurement is completed, a signal to that effect is output. When the output signal of the timer B12 after 30 seconds has elapsed, the intermittent standby operation is performed.
This intermittent waiting operation is an operation for checking whether there is communication from the other party, that is, the wireless communication means A1, and if "carrier sense" is performed and it is determined that "radio wave", it shifts to a signal receiving operation. When it is determined by "carrier sense" that "no radio wave", the operation of the wireless unit is stopped and the low power consumption operation is performed, and the next timer B16 waits for the output when 30 seconds have elapsed.
When such operation is repeated and the synchronization correction timing reaches 10 minutes, the carrier determination unit B15 causes the timer B to
When receiving the output signal indicating that 10 minutes has elapsed in 12 tentatively, “carrier sense” is performed at f ₀ . When it is determined that there is a radio wave in this "carrier sense" of f ₀ , the wireless transmission / reception means B
11 shifts to the receiving state and is sent from the other side, that is, the wireless communication means A1 at f ₀ . Receive a synchronization correction signal. Upon receiving the synchronization correction signal, the wireless transmission / reception means B11 outputs the received data to the synchronization correction signal determination means 13. The synchronization correction signal determination means 13 analyzes whether the received data is correct.

If it is correct, the measurement start value of the timer B12 is corrected according to the synchronization correction signal. Then, the response signal creating means 14 creates a response signal to the synchronization correction signal including the analysis result of the synchronization correction signal determining means 13 and transmits the response signal from the wireless transmitting / receiving means B11 at f ₀ . When the synchronization correction signal determination means 13 determines that the synchronization correction signal received by the wireless transmission / reception means B11 is correct, the wireless communication means B2
Resets the counter B16, ends the wireless communication operation, and waits for the output of the next timer B12 for the end of measurement. The synchronization correction signal determination means 13 is the wireless transmission / reception means B11.
Even when the wireless communication means B2 determines that the received synchronization correction signal is incorrect, the wireless communication means B2 sends the response signal to the synchronization correction signal to f
_{At 0} , the operation is intermittent after transmission.

On the other hand, the synchronization correction signal determination means 13 outputs a signal to that effect when the synchronization correction signal received by the wireless transmission / reception means B11 is not correct or when the wireless transmission / reception means B11 cannot receive the synchronization correction signal. . Also, the carrier determination means B15 also outputs a signal to that effect when it determines "no radio wave" in "carrier sense" of f ₀ at the synchronization correction timing every 10 minutes. In such a case, the wireless communication means B2 will receive the synchronization correction retransmission signal that should have been sent from the wireless communication means A1 at f ₀ at the next intermittent reception timing of 30 seconds.

This receiving operation is the same as the normal synchronization correction timing for every 10 minutes. When the wireless transmission / reception means B11 receives the synchronization correction retransmission signal sent from the wireless communication means A1 at f ₀ , the frequency information included therein is checked. If this frequency information is f ₂ , the wireless transmission / reception means B11 outputs a signal to that effect. In response to the signal, the frequency switching unit B18 switches the frequency of the wireless communication unit B2 for performing the standby operation for the next 30 seconds and the synchronization correction operation for every 10 minutes from f ₀ to f ₂ . The counter B16 is provided with a signal output by the synchronization correction signal determination means 13 when the synchronization correction signal received by the wireless transmission / reception means B11 is incorrect, or when the wireless transmission / reception means B11 cannot receive the synchronization correction signal, and the carrier determination means B15. When the signal output when "no radio wave" is determined by "carrier sense" at the synchronization correction timing every 10 minutes is received, the number of times is counted.
Then, if the synchronization correction communication does not end normally even if the counter B16 counts a predetermined number of times, the wireless communication means B2 returns to the "sleep mode".

FIG. 4 shows the operation timings of the wireless communication means A1 and B2 in the "data communication mode".
As can be seen from FIG. 4, the frequency switched by the frequency switching means A10 and the frequency switching means B18 is determined each time by the number of retransmissions counted by the retransmission number counting means 19 of the wireless communication means A1.

Note that the wireless communication means A1 and the wireless communication means B2 perform similar frequency switching for communication also in normal data communication other than synchronization correction communication.

[0053]

As described above, the wireless communication system of the present invention has the following effects.

(1) Synchronization correction By switching the frequency for communication or data communication, loss of synchronization or unsuccessful data communication due to influence of radio frequency of other system, random noise, burst noise, time fading, etc. This can be prevented, and the reliability of the intermittent wireless communication system can be greatly improved.

(2) By selecting one from among a plurality of stored frequency information, performing synchronization correction communication and data communication at that frequency, and further selecting the selected frequency according to a predetermined pattern, It is possible to provide a high-performance wireless communication system capable of avoiding an interfering signal to other systems as much as possible by synchronization correction communication and data communication when the own system becomes widespread. Further, depending on the method of selecting a predetermined pattern, it is possible to significantly reduce the frequency of retransmissions and the like, and it is possible to reduce the power consumption of the device.

(3) It is possible to change the frequency only by the situation judgment on the transmitting side by determining the frequency switching on the transmitting side of the synchronization correction communication and transmitting the information to the receiving side. Can be realized.

[Brief description of the drawings]

FIG. 1 is a block diagram of a wireless communication system according to an embodiment of the present invention.

FIG. 2 is a timing chart of the wireless communication system of FIG.

FIG. 3 is a block diagram of a wireless communication system according to another embodiment of the present invention.

4 is a timing chart of the wireless communication system of FIG.

FIG. 5 is a block diagram of a conventional wireless communication system.

[Explanation of symbols]

 1 wireless communication means A 2 wireless communication means B 3 wireless transmission / reception means A 4 timer A 5 synchronization correction signal generation means 6 carrier determination means A 7 response signal determination means 8 counter A 9 frequency information storage means A 10 frequency switching means A 11 wireless Transmitter / receiver B 12 Timer B 13 Synchronization correction signal determination means 14 Response signal creation means 15 Carrier determination means B 16 Counter B 17 Frequency information storage means B 18 Frequency switching means B 19 Retransmission count means

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Masafumi Nakagawa 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (3)

[Claims] 1. A wireless communication unit is turned on at predetermined time intervals to perform data communication or intermittent synchronization correction communication, and when the data communication or synchronization correction communication ends, the wireless communication unit is turned off. In a wireless communication system composed of at least one or more wireless communication means A and at least one or more wireless communication means B for performing intermittent operation,
The wireless communication means A transmits a synchronization correction signal or a data communication signal to the wireless communication means B, and a signal transmission means A.
A signal receiving means A for receiving a data communication signal from the wireless communication means B, a frequency switching means A for switching the operating frequencies of the signal transmitting means A and the signal receiving means A, and the wireless communication means B. Is a signal transmitting means B for transmitting a data communication signal to the wireless communication means A, a signal receiving means B for receiving a synchronization correction signal or a data communication signal from the wireless communication means A, the signal transmitting means B and the signal. A wireless communication system having frequency switching means B for switching the operating frequency of the receiving means B. 2. The frequency switching means A follows a frequency information storage means A for storing a plurality of frequency information and a predetermined pattern from the plurality of frequency information stored in the frequency information storage means A. Frequency information selecting means A for selecting and outputting one frequency information in synchronization with the intermittent cycle
And a communication frequency deciding means A for deciding the communication frequency of the synchronization correction communication and the data communication according to the frequency information outputted by the frequency information selecting means A, and the frequency switching means B stores a plurality of the frequency information. Frequency information storage means B and frequency information selection for selecting and outputting one frequency information from a plurality of frequency information stored in the frequency information storage means B in synchronization with the intermittent cycle according to the predetermined pattern. The wireless communication system according to claim 1, further comprising means B and communication frequency determining means B that determines a communication frequency for synchronization correction communication and data communication based on the frequency information output by the frequency information selecting means B. 3. A frequency switching means A synchronizes a frequency information storage means for storing a plurality of frequency information and one of a plurality of frequency information stored in the frequency information storage means with an intermittent cycle. The frequency information selecting means for selecting and outputting the frequency information, the signal generating means for generating the synchronization correction signal or the data communication signal including the frequency information output by the frequency information selecting means, and the frequency information outputting by the frequency information selecting means for synchronization. It has a communication frequency deciding means A for deciding the communication frequency of correction communication and data communication, and the frequency switching means B analyzes the frequency information sent from the wireless communication means A, and the signal analyzing means analyzes it. The communication frequency determining means B for determining the communication frequency of the synchronization correction communication and the data communication based on the obtained frequency information.
A wireless communication system as described.