WO2014196316A1

WO2014196316A1 - Wireless communication terminal, wireless communication system

Info

Publication number: WO2014196316A1
Application number: PCT/JP2014/062662
Authority: WO
Inventors: 大樹北山
Original assignee: 古野電気株式会社
Priority date: 2013-06-07
Filing date: 2014-05-13
Publication date: 2014-12-11
Also published as: CN105453682A; JP6407147B2; CN105453682B; JPWO2014196316A1

Abstract

[Problem] To provide a wireless communication system capable of easily establishing a channel for communicating. [Solution] This wireless communication system (1) is provided with a parent device (10) and a child device (20). The parent device (10) and child device (20) are each provided with a GPS receiving unit and a wireless communication unit. The parent device (10) and child device (20) implement carrier sense synchronized with a high-precision GPS time obtained from a GPS signal. At that time, the parent device (10) and child device (20) belonging to the same group are configured in advance so as to implement carrier sense for the same initial channel. Further, the parent device (10) and child device (20) share a method of changing the channel in the case that the initial channel is not idle. By this means, the parent device (10) and child device (20) are synchronized with the GPS time to detect idle channels with the same timing to a high degree of accuracy, making it possible to establish communication between the parent device (10) and child device (20).

Description

Wireless communication terminal, wireless communication system

The present invention relates to a wireless communication terminal and a wireless communication system that perform wireless communication with each other, and more particularly to a wireless communication terminal and a wireless communication system that perform wireless communication using a frequency-divided channel.

There is a frequency division wireless communication method as a kind of wireless communication method. In the frequency division wireless communication method, a predetermined frequency band is divided into individual frequency bands, and each individual frequency band is assigned to an individual channel. Wireless communication terminals that perform communication perform wireless communication using a common channel.

In such wireless communication, when there is a channel that is being used by another wireless communication terminal, the channel cannot be used, and another empty channel must be used.

For this reason, a technique called carrier sense as shown in Patent Document 1 has been conventionally used. Carrier sense is a technique for detecting whether or not a set channel is an empty channel before a wireless communication terminal transmits information such as voice and data from itself. , Detecting whether it is an empty channel. Here, the transmission data includes not only text data but also audio data.

In the wireless communication system described in Patent Document 1, a transmission-side wireless communication terminal detects all used channels and unused channels by carrier sense before transmission. The transmitting-side wireless communication terminal transmits information using a vacant channel that is a predetermined frequency away from the channel in use.

The receiving-side wireless communication terminal performs carrier sense on all channels and sequentially analyzes information acquired from each channel. The receiving wireless communication terminal demodulates information from the transmitting wireless communication terminal with which the receiving wireless communication terminal communicates. On the other hand, if it is not information from the transmitting wireless communication terminal with which the receiving wireless communication terminal communicates, the receiving wireless communication terminal analyzes the information of other channels.

JP 2006-140854 A

However, in the above-described method, the transmission channel is appropriately determined based on the carrier sense result of the transmission-side wireless communication terminal, but the reception-side wireless communication terminal cannot know this channel. Therefore, it is necessary to perform carrier sense for all channels every time and demodulate information for each channel.

In this case, there is a problem that it takes time to start communication.

Especially, it is conceivable that the number of channels used at the same time will increase as the transition from analog radio to digital radio is promoted and licenses are not required and use at leisure is easy. For this reason, in the above-described method, it is not easy for the transmitting-side wireless communication terminal and the receiving-side wireless communication terminal to establish communication, and it takes more time to start communication or communication is desired. Problems such as inability to communicate at the time occur.

An object of the present invention is to provide a wireless communication terminal and a wireless communication system capable of easily establishing a channel and communicating.

The present invention relates to a radio communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels to which different frequency bands are assigned, and communicates data on the empty channel. Have The wireless communication terminal includes a GPS receiver, a data transmitter, and a housing. The GPS receiving unit receives a GPS signal and detects the GPS time from the reception result. The data transmission unit detects over a predetermined time whether or not the preset channel is an empty channel in synchronization with the GPS time. If the data transmission unit is an empty channel, the data transmission unit transmits data using the set channel. If not, the data transmission unit sets another channel after a predetermined time to detect whether the channel is an empty channel. The housing is provided with a GPS receiver and a data transmitter.

In this configuration, the data transmission unit performs carrier sense in order of channels until a free channel is detected in accordance with a predetermined rule in advance. At this time, since the carrier sense is synchronized with the GPS time, the wireless communication terminal on the receiving side, which is the object of data communication, similarly performs the carrier sense in synchronization with the GPS time, so that communication using an empty channel is performed. Is easily realized.

Further, in the wireless communication terminal of the present invention, the data transmission unit sets a channel that does not interfere with a detected channel if it is not an empty channel as a new another channel.

In this configuration, mutual interference between data communication using a channel currently used by another wireless communication terminal and data communication using a detected empty channel can be prevented.

The present invention also relates to a wireless communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels to which different frequency bands are assigned, and communicates data on the empty channel. The wireless communication terminal includes a GPS receiver, a data receiver, and a housing. The GPS receiving unit receives a GPS signal and detects the GPS time from the reception result. The data receiving unit detects whether or not the preset channel is an empty channel in synchronization with the GPS time over a predetermined time. If the channel is an empty channel, the data receiving unit receives the data on the set channel. If not, another channel is set after a predetermined time to detect whether it is an empty channel. The housing is provided with a GPS receiver and a data receiver.

In this configuration, the data reception unit performs carrier sense in order of channels until a free channel is detected in accordance with a predetermined rule. At this time, since the carrier sense is synchronized with the GPS time, the transmission side wireless communication terminal that is the object of data communication performs the carrier sense in the same manner in synchronization with the GPS time, so that communication using an empty channel is performed. Is easily realized.

The present invention also relates to a wireless communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels to which different frequency bands are assigned, and communicates data on the empty channel. The wireless communication terminal includes a GPS receiver and a data receiver. The GPS receiving unit receives a GPS signal and detects the GPS time from the reception result. The data receiving unit starts timing in synchronization with the GPS time, is in a sleep state during the first set time, starts after the first set time, and performs reception processing on a preset channel. If valid data cannot be received by this reception process, the data reception unit switches the channel in synchronization with the GPS time, and performs the reception process on a channel different from the preset channel.

In this configuration, the data reception unit performs reception processing in the order of channels in accordance with a predetermined rule in advance. At this time, since the reception process is synchronized with the GPS time, the transmission side wireless communication terminal that is the object of data communication performs the carrier sense and the data transmission process similarly in synchronization with the GPS time. Establishing communication using the network is easily realized. Moreover, since it will be in a sleep state until the start of a reception process, the power consumption of a radio | wireless communication terminal can be reduced.

The present invention also relates to a wireless communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels to which different frequency bands are assigned, and communicates data on the empty channel. The wireless communication terminal includes a GPS receiver and a data receiver. The GPS receiving unit receives a GPS signal and detects the GPS time from the reception result. The data receiving unit starts timing in synchronization with the GPS time, is in a sleep state during the first set time, starts after the first set time, and performs reception processing on a preset channel. If valid data cannot be received by this reception process, the data receiving unit goes into a sleep state during the second set time, restarts after the second set time, and uses a channel different from the preset channel. Perform reception processing.

In this configuration, the data reception unit performs reception processing in the order of channels in accordance with a predetermined rule in advance. At this time, since the reception process is synchronized with the GPS time, the transmission side wireless communication terminal that is the object of data communication performs the carrier sense and the data transmission process similarly in synchronization with the GPS time. Establishing communication using the network is easily realized. In addition, since it is in a sleep state except during reception processing, the power consumption of the wireless communication terminal can be reduced.

Also, the present invention provides a wireless communication system for communicating data between a first wireless communication terminal and a second wireless communication terminal using a free channel among a plurality of channels to which different frequency bands are assigned. It is about. In this wireless communication system, the first wireless communication terminal is a wireless communication terminal including the above-described data transmitting unit, and the second wireless communication terminal is a wireless communication terminal including the above-described data receiving unit. The data transmission unit of the first wireless communication terminal and the data reception unit of the second wireless communication terminal perform channel setting in synchronization with the GPS time.

In this configuration, the first wireless communication terminal that is the wireless communication terminal on the transmission side and the second wireless communication terminal that is the wireless communication terminal on the reception side are configured as described above, so that communication using an empty channel can be performed. Establishment is easy. In particular, as described above, in the case of a portable wireless communication terminal driven by a battery, the process from detection of an empty channel to establishment of communication is simplified, and the battery of each wireless communication terminal, particularly the wireless communication terminal on the receiving side is The life can be extended.

In the wireless communication system of the present invention, there are a plurality of first wireless communication terminals. The first wireless communication terminal temporarily interrupts the first communication during the first communication, executes the second communication with the second wireless communication terminal during the interruption, and performs the second communication. The first communication is resumed after the end of.

In this configuration, while one communication is being executed, another communication can be interrupted.

According to the present invention, a wireless communication terminal and a wireless communication system capable of easily establishing a channel and communicating can be realized.

1 is a block diagram illustrating a configuration of a wireless communication system according to a first embodiment of the present invention. It is a flowchart which shows the processing flow of the main | base station 10 which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the processing flow of the subunit | mobile_unit 20 which concerns on the 1st Embodiment of this invention. It is a time chart for demonstrating the concept of communication establishment of the radio | wireless communications system 1 which concerns on the 1st Embodiment of this invention. It is a flowchart which shows the processing flow of the subunit | mobile_unit which concerns on the 2nd Embodiment of this invention. It is a time chart for demonstrating the concept of communication establishment of the radio | wireless communications system which concerns on the 2nd Embodiment of this invention. It is a flowchart which shows the communication establishment method between the main | base station subunit | mobile_unit in which the some main | base station is in a call in the radio | wireless communications system of this invention.

The wireless communication system according to the first embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a block diagram showing a configuration of a radio communication system according to the first embodiment of the present invention.

The wireless communication system 1 includes a master unit 10 and a slave unit 20. Master device 10 corresponds to a “first wireless communication terminal” of the present invention, and slave device 20 corresponds to a “second wireless communication terminal” of the present invention. The parent device 10 and the child device 20 include a casing having a portable shape. The parent device 10 is carried by an administrator, for example, and the child device 20 is attached to an animal, for example.

In this embodiment, both the parent device 10 and the child device 20 are assumed to be portable, and an example of being worn on a person or an animal is shown. However, even if at least one is a stationary wireless communication system, Configuration can be applied.

The master unit 10 and the slave unit 20 divide the communicable frequency band into a plurality of frequency bands, and perform transmission / reception of communication data by a digital wireless communication method in which each of the divided frequency bands is assigned to individual channels. As communication data, necessary data such as text data and voice data may be used.

The parent device 10 includes a calculation unit 111, a GPS reception unit 112, a wireless communication unit 113, a storage unit 114, a battery 115, an operation unit 116, a display unit 117, a GPS antenna 121, and a communication antenna 131. Each of these parts constituting the base unit 10 is built in or externally mounted on the casing. The battery can be omitted. In this case, base unit 10 may be connected to an external power supply and receive power supply from the external power supply.

The calculation unit 111 is connected to the GPS reception unit 112, the wireless communication unit 113, the storage unit 114, the battery 115, the operation unit 116, and the display unit 117. The calculation unit 111 performs overall control of the parent device 10.

The calculation unit 111 receives an operation input from the operation unit 116 and controls data transmission / reception processing. Until the communication with the child device 20 is established, the calculation unit 111 performs a carrier sense by a method described later, and performs a process for establishing communication with the child device 20. The arithmetic unit 111 performs control to transmit the generated communication data from the wireless communication unit 113 after communication with the child device 20 is established. In addition, the calculation unit 111 performs control to display the communication data demodulated by the wireless communication unit 113 on the display unit 117.

The GPS receiver 112 is connected to the GPS antenna 121. The GPS receiver 112 demodulates the navigation message of the GPS signal received by the GPS antenna 121 and detects the GPS time. The GPS receiving unit 112 outputs the detected GPS time to the calculation unit 111.

The wireless communication unit 113 is connected to the communication antenna 131. The wireless communication unit 113 converts the communication data into a predetermined format, generates transmission data, and transmits the transmission data from the communication antenna 131 to the outside. After the communication with the child device 20 is established, the wireless communication unit 113 demodulates the wireless signal (received signal) received by the communication antenna 131, demodulates the received data, and acquires the communication data. The wireless communication unit 113 outputs a reception signal to the calculation unit 111 until communication with the child device 20 is established.

The storage unit 114 stores carrier sense information executed by the calculation unit 111 and a data transmission / reception processing program. The calculation unit 111 reads and executes the program stored in the storage unit 114 to control carrier sense and data transmission / reception processing. The storage unit 114 can also be used as a calculation memory used when the calculation unit 111 executes a program.

The battery 115 supplies power to each unit of the base unit 10. The battery 115 can supply power only to the calculation unit 111 in the sleep state, and can supply power to each unit constituting the parent device 10 when activated from the sleep state. This power control is executed by the calculation unit 111.

The operation unit 116 includes various operators such as buttons arranged on the outer surface of the casing. The operation unit 116 detects operation information and outputs it to the calculation unit 111. The display unit 117 includes a display panel (for example, a liquid crystal display) disposed on the outer surface (front surface) of the housing. The display unit 117 displays an image by display control from the calculation unit 111. For example, information indicating that carrier sense is being performed is displayed during carrier sense, and information indicating that communication has been established and data is being transmitted / received to / from a communication target is displayed during data transmission / reception. Further, it is possible to display the position information of the communication partner (such as the child device 20) obtained by communication and the position information of the parent device 10 itself.

The subunit | mobile_unit 20 is provided with the calculating part 211, the GPS receiving part 212, the radio | wireless communication part 213, the memory | storage part 214, the battery 215, the GPS antenna 221, and the communication antenna 231. Each of these parts constituting the slave unit 20 is built in or externally provided in the casing. As a basic configuration, the slave unit 20 is obtained by omitting the operation unit 116 and the display unit 117 from the master unit 10. The housing of the child device 20 is preferably formed smaller than the housing of the parent device 10. The battery can be omitted. In this case, the subunit | mobile_unit 20 should just connect with an external power supply and receive electric power supply from the said external power supply.

The computing unit 211 is connected to the GPS receiving unit 212, the wireless communication unit 213, the storage unit 214, and the battery 215. The computing unit 211 performs overall control of the slave unit 20.

The calculation unit 211 performs carrier sense by a method described later before communication with the parent device 10 and then performs processing for establishing communication with the parent device 10. After the communication with the base unit 10 is established, the arithmetic unit 211 performs an external notification process or the like based on the communication data demodulated by the wireless communication unit 113, for example. As the external notification process, for example, a process of generating a sound from a speaker or the like (not shown) or vibrating a casing using a vibrator or the like (not shown) can be considered.

The GPS receiver 212 is connected to the GPS antenna 221. The GPS receiver 212 demodulates the navigation message of the GPS signal received by the GPS antenna 221 and detects the GPS time. The GPS receiver 212 outputs the detected GPS time to the calculator 211.

The wireless communication unit 213 demodulates the wireless signal (received signal) received by the communication antenna 231 after communication with the base unit 10 is established, and acquires communication data. The wireless communication unit 213 outputs a reception signal to the calculation unit 211 until communication with the parent device 10 is established. Note that the wireless communication unit 213 may have a configuration capable of executing transmission data generation processing, similar to the wireless communication unit 113 of the parent device 10.

The storage unit 214 stores carrier sense information executed by the calculation unit 211 and a data reception processing program. The calculation unit 211 controls carrier sense and data reception processing by reading and executing the program stored in the storage unit 214. The storage unit 214 can also be used as a calculation memory used when the calculation unit 211 executes a program.

The battery 215 supplies power to each unit of the slave unit 20. The battery 215 can supply power only to the arithmetic unit 211 in the sleep state, and can supply power to each unit constituting the slave unit 20 when activated from the sleep state. This power control is executed by the calculation unit 211.

The wireless communication system 1 including the parent device 10 and the child device 20 having such a configuration executes communication establishment processing using the following method. FIG. 2 is a flowchart showing a processing flow of the parent device 10 according to the first embodiment of the present invention. FIG. 3 is a flowchart showing a processing flow of the handset 20 according to the first embodiment of the present invention.

(1) Processing of base unit 10 The computing unit 111 of the base unit 10 detects the GPS time acquired by the GPS receiving unit 112 (S101). The calculation unit 111 performs time management by the time measuring unit provided in the calculation unit 111 until the communication time that is the preset carrier sense execution time is reached (S102: NO). Note that the calculation unit 111 may continuously detect the GPS time. When the calculation unit 111 detects that the communication time has come (S102: YES), the calculation unit 111 sets an initial channel set for each parent device or child device of the group to which the parent device 10 belongs. The calculation unit 111 performs carrier sense on the frequency band of the initial channel (S103).

At the time of carrier sense, the calculation unit 111 detects the amplitude level and power of the signal received via the communication antenna 131 and the wireless communication unit 113. When calculating unit 111 detects a signal with a predetermined amplitude level or higher or a predetermined power or higher, it determines that the initial channel has already been used. That is, the calculation unit 111 determines that the channel is not an empty channel. The calculation unit 111 determines that the initial channel is an empty channel if a signal having a predetermined amplitude level or higher or a predetermined power or higher is not detected.

If the initial channel is an empty channel (S104: YES), the calculation unit 111 prepares for data transmission using the initial channel (S105). The calculation unit 111 performs data transmission using the initial channel after preparation for data transmission (S106).

If the initial channel is not an empty channel (S104: NO), the calculation unit 111 changes the set channel according to the method set in the group. For example, the calculation unit 111 sets a new channel m as m = n + 6 as the current channel n. Note that the channel change method is an example, and other methods may be used. For example, the new channel m is set such that the newly set channel m and the channel n determined not to be an empty channel (channel used by another wireless communication terminal) n do not interfere with each other.

The calculation unit 111 performs carrier sense for the newly set channel (S111).

The calculation unit 111 repeats this process until an empty channel is detected. When an empty channel is detected (S104: YES), it prepares for transmission (S105) and executes data transmission (S106).

By performing such processing, the base unit 10 can efficiently set an empty channel and perform data transmission.

(2) Processing of handset 20 The computing unit 211 of the handset 20 detects the GPS time acquired by the GPS receiving unit 212 (S201). The calculation unit 211 performs time management by the time measuring unit provided in the calculation unit 111 until the communication time that is the preset carrier sense execution time is reached (S202: NO). Note that the calculation unit 111 may continuously detect the GPS time. When the calculation unit 211 detects that the communication time has come (S202: YES), the calculation unit 211 sets an initial channel set for each parent device or child device of the group to which the child device 20 belongs. The calculation unit 211 performs carrier sense on the frequency band of the initial channel (S203). The method of carrier sense is the same as that of base unit 10.

When the initial channel is an empty channel (S204: YES), the calculation unit 211 receives data using the initial channel (S205).

If the initial channel is not an empty channel (S204: NO), the calculation unit 211 changes the set channel according to the method set in the group. The setting channel changing process is the same as that of the parent device 10 belonging to the same group.

The calculation unit 211 performs carrier sense for the newly set channel (S211).

The calculation unit 211 repeats this process until an empty channel is detected, and when an empty channel is detected (S204: YES), data reception is executed (S205).

By performing such processing, the slave unit 20 can efficiently set an empty channel and perform data transmission. In addition, communication with the parent device 10 can be easily established by detecting an empty channel in the same manner as the parent device 10 belonging to the same group. Furthermore, since the carrier sense timing of the parent device 10 and the carrier sense timing of the child device 20 belonging to the same group are synchronized by the GPS time, communication can be established more reliably. In particular, since GPS time has high time accuracy, communication can be established more reliably.

FIG. 4 is a time chart for explaining the concept of communication establishment of the wireless communication system 1 according to the first embodiment of the present invention. FIG. 4A shows a case where communication is not performed except for the master unit 10 and the slave unit 20. FIG. 4B shows a case where a wireless device other than the parent device 10 and the child device 20 is communicating. FIG. 4 shows a case where channel CH1 is used as the initial channel. In addition, as a channel setting change method, m = n + 6 is used as a new channel m and channel n determined to be in use. In FIG. 4, the length representing each time length is set as appropriate for easy understanding of the description, and is not necessarily the same as the ratio of actual time lengths.

(A) When communication is not performed other than the parent device 10 and the child device 20 belonging to the same group. The parent device 10 and the child device 20 perform carrier sense on the initial channel CH1 in synchronization with a certain GPS time. The carrier sense is executed for a predetermined time length Tcs starting from the GPS time. The time length Tcs and the following time lengths are measured by a time measuring unit provided in the calculation unit 111 of the parent device 10 and the calculation unit 211 of the child device 20. Since no wireless communication terminal is communicating, the parent device 10 and the child device 20 do not detect the carrier of other wireless communication terminals, and determine the initial channel CH1 as an empty channel.

Master device 10 prepares for transmission during time length Ttp after time length Tcs from GPS time. Base unit 10 performs data transmission using channel CH1 with time length Ttx after time length Ttp has elapsed.

The subunit | mobile_unit 20 performs reception preparation after time length Tcs from GPS time, and receives data using channel CH1. At this time, the wait time may be set so that the data transmission time of the parent device 10 and the data reception time of the child device 20 are synchronized.

Thereafter, the master unit 10 and the slave unit 20 perform data transmission / reception using the channel CH1. In addition, the main | base station 10 and the subunit | mobile_unit 20 by which data communication was established may select a channel for every data transmission / reception after that, and may continue data communication. At this time, the master unit 10 and the slave unit 20 may perform channel selection according to the above-described channel setting change method, and may include the next channel information in the data communication currently being performed.

(B) A case where a wireless device other than the parent device 10 and the child device 20 belonging to the same group is communicating.

The parent device 10 and the child device 20 perform carrier sense on the initial channel CH1 in synchronization with a certain GPS time. The carrier sense is executed for a predetermined time length Tcs starting from the GPS time. Since the other wireless devices are already communicating, the parent device 10 and the child device 20 detect the carrier of the other wireless communication terminal and determine that the initial channel CH1 is a channel in use.

The parent device 10 and the child device 20 set the channel CH7 according to the channel setting change method of the group to which the group belongs after the time length Tcs from the GPS time. The parent device 10 and the child device 20 again perform carrier sense for the time length Tcs.

Since no wireless communication terminal is communicating on this channel CH7, the parent device 10 and the child device 20 do not detect carriers of other wireless communication terminals, and determine that the channel CH7 is an empty channel.

Base unit 10 prepares for transmission during time length Ttp after two time lengths Tcs (Tcs × 2) from GPS time. After the time length Ttp has elapsed, base unit 10 performs data transmission using channel CH7 with time length Ttx.

The subunit | mobile_unit 20 performs reception preparation after the time length Tcs (Tcs * 2) twice from GPS time, and receives data using channel CH7 by time length Trx (= Ttx).

Thereafter, the master unit 10 and the slave unit 20 perform data transmission / reception using the channel CH7. Also in this case, the parent device 10 and the child device 20 for which data communication has been established may subsequently select the channel for each data transmission / reception and continue the data communication. At this time, the master unit 10 and the slave unit 20 may perform channel selection according to the above-described channel setting change method, and may include the next channel information in the data communication currently being performed.

If a free channel cannot be detected on channel CH7, the master unit 10 and the slave unit 20 repeat the above-described process to detect a free channel and establish communication. Here, when the carrier is detected during the carrier sense of the parent device 10 and the child device 20, the carrier sense may be aborted and the carrier sense time length Tcs may be shortened.

By using the configuration and processing as described above, the parent device 10 and the child device 20 belonging to the same group can easily establish communication. In particular, as described above, even when the handset 20 cannot operate a wireless communication terminal such as an animal, communication can be reliably established. Further, as shown in the prior art, since it is not necessary to carry out carrier sense for all channels with a single carrier sense, the process for establishing communication can be simplified, and simplification of processing and power saving can be realized.

Next, a radio communication system according to the second embodiment of the present invention will be described with reference to the drawings. In the wireless communication system of the present embodiment, the processing of the slave unit 20 is different, and the processing of the master unit 10 and the configurations of the master unit 10 and the slave unit 20 are the same. Therefore, only different parts will be described. FIG. 5 is a flowchart showing a processing flow of the slave unit according to the second embodiment of the present invention.

The computing unit 211 of the child device 20 detects the GPS time acquired by the GPS receiving unit 212 (S201). The calculation unit 211 manages the time by the time measuring unit provided in the calculation unit 211 until the communication time that is the preset carrier sense execution time is reached (S202: NO). During this time, the calculation unit 211 performs power control so that power is not supplied to anything other than the calculation unit 211. That is, the calculating part 211 controls the subunit | mobile_unit 20 to a sleep state. When the calculation unit 211 detects that the communication time has come (S202: YES), the calculation unit 211 further maintains the sleep state for a predetermined time length Tw1. The time length Tw1 is set to the same time length as the time length Tcs at which the base unit 10 performs carrier sense. The calculation unit 211 activates the wireless communication unit 213 after the time length Tw1 from the GPS time (S223). The calculation unit 211 receives data on the initial channel after activation. At this time, the calculation unit 211 performs data detection with the time length Trx0 (S224). The time length Trx0 is set shorter than the data transmission time length Ttx of the parent device 10. The data detection process is a process for determining whether or not the detected communication data is data from a wireless communication terminal (master device 20) of a group to which the slave device 20 belongs. Specifically, for example, the calculation unit 211 extracts the group ID from the received data, detects that there is received data if the group ID of the group to which the child device 20 belongs, and can detect the group ID of another group. If there is no received data, it is detected. Similarly, when the received data cannot be demodulated normally, it is detected that there is no received data.

When the calculation unit 211 detects that reception data is present (S225: YES), the calculation unit 211 receives data with a time length Trx (= Ttx) with reference to the activation timing (S226).

When the calculation unit 211 detects that there is no reception data (S225: NO), it shifts to the sleep state again (S227). The calculation unit 211 measures the predetermined time length Tw2 after shifting to the sleep state again. After the time length Tw2 has elapsed, the calculation unit 211 changes the setting channel according to the method set in the group and restarts (S228). Then, the received data is detected again (S224).

The time length Tw2 is a time length obtained by subtracting the time length Trx0 from the time length Tcs. Thereby, the time of a sweep state can be ensured long.

The slave unit 20 can easily establish communication with the master unit 10 by performing such processing. Furthermore, power is not consumed except by the calculation unit 111 outside the reception data detection period and the data reception period. Therefore, the power of the slave unit 20 can be further reduced, and the power source of the slave unit 20 can be extended.

FIG. 6 is a time chart for explaining the concept of communication establishment of the wireless communication system according to the second embodiment of the present invention. FIG. 6A shows a case where communication is not performed except for the parent device 10 and the child device 20. FIG. 6B shows a case where a wireless device other than the parent device 10 and the child device 20 is communicating. FIG. 6 shows a case where channel CH1 is used as the initial channel. In addition, as a channel setting change method, m = n + 6 is used as a new channel m and channel n determined to be in use.

(C) When communication is not performed other than the parent device 10 and the child device 20 belonging to the same group. The parent device 10 performs carrier sense on the initial channel CH1 in synchronization with a certain GPS time. The carrier sense is executed for a predetermined time length Tcs starting from the GPS time. The subunit | mobile_unit 20 maintains a sleep state for time length Tw1 starting from the said GPS time, synchronizing with the GPS time same as the GPS time which the main | base station 10 synchronizes. As described above, the time length Tw1 of the slave unit 20 in the sleep state coincides with the carrier sense time length Tcs of the base unit 10. The time lengths Tcs, Tw1 and the following time lengths are measured by the time measuring units provided in the arithmetic unit 111 of the parent device 10 and the arithmetic unit 211 of the child device 20.

Since only the master unit 10 and the slave unit 20 are communicating, the master unit 10 does not detect the carrier of another wireless communication terminal, and determines the initial channel CH1 as an empty channel.

The subunit | mobile_unit 20 returns from a sleep state after time length Tw1 from GPS time, and performs reception data detection using channel CH1 by time length Trx0. The subunit | mobile_unit 20 detects that it is the data from the main | base station 10 of the same group, and continues receiving data. At this time, handset 20 receives data with time length Trx starting from the detection timing of the received data.

Thereafter, the master unit 10 and the slave unit 20 perform data transmission / reception using the channel CH1. Also in this case, the parent device 10 and the child device 20 for which data communication has been established may subsequently select the channel for each data transmission / reception and continue the data communication. At this time, the master unit 10 and the slave unit 20 may perform channel selection according to the above-described channel setting change method, and may include the next channel information in the data communication currently being performed.

(D) Indicates a case where other wireless devices other than the parent device 10 and the child device 20 belonging to the same group are communicating.

Base unit 10 performs carrier sense on initial channel CH1 in synchronization with a certain GPS time. The carrier sense is executed for a predetermined time length Tcs starting from the GPS time. The subunit | mobile_unit 20 maintains a sleep state for time length Tw1 starting from the said GPS time, synchronizing with the GPS time same as the GPS time which the main | base station 10 synchronizes.

Since the other wireless device is already communicating, the base unit 10 detects the carrier of the other wireless communication terminal and determines that the initial channel CH1 is a channel in use.

Base unit 10 sets channel CH7 according to the channel setting change method of the group to which these groups belong after time length Tcs from GPS time. Base unit 10 again performs carrier sense for time length Tcs. Since no wireless communication terminal is communicating with channel CH7, base unit 10 does not detect the carrier of another wireless communication terminal and determines channel CH7 as an empty channel.

The subunit | mobile_unit 20 returns from a sleep state after time length Tw1 from GPS time, and performs reception data detection using channel CH1 by time length Trx0. Since base unit 10 is performing carrier sense of channel CH7 at this time, handset 20 cannot detect data from base unit 10 in the same group. The subunit | mobile_unit 20 transfers again to a sleep state based on this result. The subunit | mobile_unit 20 maintains a sleep state for time length Tw2 from the transition timing to a sleep state as a starting point.

The subunit | mobile_unit 20 returns from a sleep state again after time length Tw2, and performs reception data detection using channel CH7 after setting change with time length Trx0. At this time, as described above, base unit 10 is preparing for transmission using channel CH7. Then, base unit 10 transmits data after preparing for transmission. Therefore, the subunit | mobile_unit 20 can detect the reception data from the main | base station 10 during time length Trx0. The subunit | mobile_unit 20 continues data reception using channel CH7 by time length Trx from the detection timing of reception data as a starting point.

If a free channel cannot be detected on channel CH7, the master unit 10 and the slave unit 20 repeat the above-described process to detect a free channel and establish communication. At this time, the slave unit 20 establishes communication while repeating the transition to and return from the sleep state.

By using the configuration and processing as described above, the parent device 10 and the child device 20 belonging to the same group can easily establish communication. In particular, if the configuration of the present embodiment is used, the power consumption of the handset 20 can be reduced. Therefore, as described above, when the handset 20 is mounted on a hound and the battery of the handset 20 cannot be replaced, the power supply of the handset 20 can be extended and more useful. .

In the above-described embodiment, when the carrier sense time length is sufficiently shorter than the data transmission time length, the slave unit 20 also performs channel switching together with channel switching of the master unit 10 to detect received data. May be performed.

In the above-described embodiment, the case where the parent device is a wireless communication terminal on the transmission side and the child device is a wireless communication terminal on the reception side is shown. However, the slave unit may be used as a wireless communication terminal on the transmission side, and the master unit may be used as a wireless communication terminal on the reception side.

In addition, the case where wireless communication is performed with one master unit and one slave unit has been shown. However, when there are multiple master units, when there are multiple slave units, even when there are multiple master units and slave units. The above-described configuration can be applied. At this time, the above-described configuration and processing can be applied to communication between parent devices and communication between child devices.

In addition, when there are a plurality of master units, there may be a situation where a call is made between the master units. Even in such a case, data communication between the parent device and the child device can be established by performing the following processing.

FIG. 7 is a flowchart showing a method for establishing communication between a master unit and a slave unit while a plurality of master units are talking in the wireless communication system of the present invention.

Each parent device and each child device acquires GPS time. The parent device and the child device perform time management by the timekeeping units provided in the parent device and the child device until the communication time that is the preset carrier sense execution time is reached (S301: NO). Note that the parent device and the child device may continuously detect the GPS time.

When each parent device detects that the communication time has come (S301: YES), if the first parent device is in a call with the second parent device (S302), the call during the parent period is temporarily suspended (S302). S303). In other words, each master unit temporarily suspends communication of audio data. This communication of audio data corresponds to the “first communication” of the present invention. The parent device and the child device perform carrier sense on the channel set in the group using the method described in the above embodiments (S304). For example, the master unit sets the channel used for communication with another master unit as a channel for carrier sense. Further, the slave unit detects a channel during a call from the communication data of each master unit, and sets the detected channel as a channel for carrier sense. Alternatively, the parent device and the child device set a preset initial channel as a channel for carrier sense. By performing such processing, the parent device and the child device in the same group can perform carrier sense at the same timing on the same channel.

If the carrier sense channel is an empty channel (unless used by another group), the parent device or the child device performs data communication with the child device or the parent device by using the channel ( S305). This data communication includes only text data having a relatively small amount of data such as position information of the slave unit. This data communication corresponds to the “second communication” of the present invention.

When the master unit acquires necessary data from the slave unit, it resumes the call with another master unit again (S306).

By performing such processing, communication can be temporarily established with the slave unit and necessary information can be acquired even when a plurality of master units are busy. In addition, such data communication between the parent device and the child device is performed in an extremely short time compared to voice data communication for a call. Therefore, it is possible to make a call substantially continuously without interrupting the communication between the parent devices so that the communication is uncomfortable.

In the above-described embodiment, the case where the first communication has a larger data amount than the second communication has been described. However, for example, the data amount relationship is not limited to this, for example, the data amount is the same.

In the above description, an example in which a display unit is provided in the master unit is shown, but the display unit may be omitted.

In the above description, the example in which the child machine is attached to an animal (for example, a hound) has been shown. It is valid.

1: wireless communication system,
10: Master unit (first wireless communication terminal),
20: Slave unit (first wireless communication terminal),
111, 211: arithmetic unit,
112, 212: GPS receiver,
121, 221: GPS antenna,
113, 213: wireless communication unit,
131, 231: Communication antenna,
114, 214: storage unit,
115, 215: battery,
116: operation unit,
117: Display unit

Claims

A wireless communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels each assigned a different frequency band, and communicates data on the empty channel,
A GPS receiver that receives a GPS signal and detects GPS time from the reception result;
In synchronization with the GPS time, it is detected over a predetermined time whether or not the preset channel is an empty channel. If it is an empty channel, data is transmitted on the set channel. A data transmitter that detects whether the channel is an empty channel by setting another channel after
A housing provided with the GPS receiver and the data transmitter;
Wireless communication terminal equipped with.
The wireless communication terminal according to claim 1,
The wireless communication terminal, wherein the data transmission means sets a channel that does not interfere with a channel detected as not being an empty channel as the other channel.
A wireless communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels each assigned a different frequency band, and communicates data on the empty channel,
A GPS receiver that receives a GPS signal and detects GPS time from the reception result;
In synchronization with the GPS time, it is detected over a predetermined time whether or not the preset channel is an empty channel. If it is an empty channel, data is received on the set channel. A data receiver that detects whether it is an empty channel by setting another channel after
A housing provided with the GPS receiver and the data receiver;
Wireless communication terminal equipped with.
A wireless communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels each assigned a different frequency band, and communicates data on the empty channel,
A GPS receiver that receives a GPS signal and detects GPS time from the reception result;
Time measurement starts in synchronization with the GPS time, and is in the sleep state for the first set time, and starts after the first set time, performs reception processing on a preset channel, and is effective by the reception processing. If data cannot be received, the channel is switched in synchronization with the GPS time, and a data receiving unit that performs reception processing on a channel different from the preset channel;
Wireless communication terminal equipped with.
A wireless communication terminal that detects whether or not a set channel is an empty channel among a plurality of channels each assigned a different frequency band, and communicates data on the empty channel,
A GPS receiver that receives a GPS signal and detects GPS time from the reception result;
Time measurement starts in synchronization with the GPS time, and is in the sleep state for the first set time, and starts after the first set time, performs reception processing on a preset channel, and is effective by the reception processing. If data cannot be received, the data receiving unit enters a sleep state during the second setting time, restarts after the second setting time, and performs reception processing on a channel different from the preset channel;
Wireless communication terminal equipped with.
A wireless communication system for communicating data between a first wireless communication terminal and a second wireless communication terminal using an empty channel among a plurality of channels each assigned a different frequency band,
The first wireless communication terminal is the wireless communication terminal according to claim 1 or claim 2,
The second wireless communication terminal is the wireless communication terminal according to any one of claims 3 to 5,
The wireless communication system, wherein the data transmission unit of the first wireless communication terminal and the data reception unit of the second wireless communication terminal set a channel in synchronization with the GPS time.
The wireless communication system according to claim 6,
There are a plurality of the first wireless communication terminals,
The first wireless communication terminal is
Temporarily interrupting the first communication during the first communication,
Performing the second communication with the second wireless communication terminal during the interruption;
Resuming the first communication after the end of the second communication;
Wireless communication system.