JP7064933B2 - Wireless control device, wireless terminal device and impulse wireless communication system - Google Patents

Description

INDUSTRIAL APPLICABILITY In an impulse wireless communication system, when there is another adjacent impulse wireless communication system, the present invention is a wireless control device, a wireless terminal device, and an impulse wireless communication that switch communication methods according to the communication environment to transmit and receive data information. Regarding the system.

Conventionally, there has been known a technique of examining the attributes of information to be wirelessly transmitted and selecting whether to perform wireless transmission of each information by time hopping or transmission of each information by a band reservation method based on the attributes. .. Here, the "information attribute" is, for example, a feature or characteristic that can determine whether or not each information is suitable for information transmission by time hopping, and as an example, whether or not each information is stream transmission. The information indicating the above, or the amount of information transmitted, can be an "attribute of information".

For example, FIG. 12 (corresponding to FIG. 3 of Patent Document 1) shows a configuration example of a frame used for information transmission by the above technique. In the configuration example of this frame, the transmission frame cycle 41 is defined at predetermined time intervals, and the information transmission area 43 is provided in synchronization with this. The information transmission area 43 includes a band reserved transmission area 45 for performing band reserved transmission between transmission devices, a time hopping area 46, and information transmission in its own network so that other networks can preferentially perform information transmission. It consists of an unused area 47 that is not used for. In this case, it is necessary to synchronize between the systems in order to perform band reservation transmission.

According to this configuration, information transmission by time hopping and band reserved transmission are appropriately selected for information transmission, so that appropriate information transmission within the wireless network is performed even if interference with other wireless networks may occur. be able to.

Japanese Patent Application Laid-Open No. 2003-110571

However, when the communication system uses the band reservation method, there is a problem that asynchronous communication cannot be performed because it is necessary to synchronize between the adjacent communication system and the communication system. Further, there is also a problem that communication cannot be performed in the communication system during the time zone when another adjacent communication system uses the band reservation method.

Further, when the above time hopping method is used, there is also a problem that as the number of users increases, the probability of packet collision increases in asynchronous communication and the communication quality is significantly deteriorated.

Therefore, an object of the present invention is to provide a means for solving such a problem.

In order to solve the above problems, the present invention adopts the following configuration.

That is, the invention according to claim 1 is
A wireless control device that sends and receives data information in an impulse wireless communication system.
Based on the information transmitted from the other impulse radio communication system, the number of the other impulse radio communication systems located around the radio control device is detected, and the number of the other impulse radio communication systems is based on the number of the other impulse radio communication systems. A control unit that determines the communication method implemented in the impulse wireless communication system as the first communication method or the second communication method.
A transmission / reception unit that broadcasts information for executing the first communication method or the second communication method.
In the first communication method, one frame is assigned to one bit of data information, a plurality of time slots are assigned to the one frame, and a time hopping code unique to the impulse wireless communication system is assigned. One time slot for transmitting and receiving one bit of the data information based on the column is assigned from the plurality of time slots, and the process is executed.
In the second communication method, a plurality of frames are assigned to one bit of data information, and a plurality of time slots are assigned to each frame of the plurality of frames, which is unique to the impulse wireless communication system. It is characterized by including a time hopping processing unit that executes a process in which one time slot for transmitting / receiving one bit of the data information is assigned to each frame based on the time hopping code string of the above.

According to the above configuration, the first communication method with low redundancy and the second communication method with high redundancy can be dynamically switched according to the number of adjacent systems, so that communication suitable for the communication environment can be performed. The method can be selected. That is, even if the number of adjacent systems increases, a code (TH code) unique to each system is used, so that it is possible to reduce the packet collision probability and improve the communication quality without adopting the bandwidth reservation method. become.

That is, the invention according to claim 2 is
In the wireless control device according to claim 1, the control unit is
It is characterized in that the other impulse radio communication system and the radio control device are operated asynchronously.

According to the above configuration, since the band reservation method that requires synchronization is not adopted, it is possible to solve the problem that communication cannot be performed in the communication system during the time zone when another adjacent communication system uses the band reservation method. Can be done.

That is, the invention according to claim 3 is
In the wireless control device according to claim 1 or 2.
The one bit transmitted / received in one time slot for transmitting / receiving the data information further includes a direct spread processing unit that executes a process distributed by a direct spread code string unique to the impulse wireless communication system. It is a feature.

According to the above configuration, even if the number of adjacent systems increases, the data is distributed using a unique code (DS code) different for each system, so that the influence of packet collision is reduced and the communication quality is improved. Will be possible.

That is, the invention according to claim 4 is
The wireless control device according to claim 3 is characterized in that the direct spread code string differs depending on the bit value of the data information.

According to the above configuration, since the pattern of the communication data to be communicated differs not only by the presence or absence of the data but also by the value of the data, it is possible to reduce the collision probability of the packet and improve the communication quality.

That is, the invention according to claim 5 is
In the wireless control device according to any one of claims 1 to 4.
In the second communication method, the time hopping processing unit is assigned to each frame of the plurality of frames assigned to one bit of the data information in response to an increase or decrease in the number of the other impulse wireless communication systems. It is characterized by executing a process of increasing or decreasing the number of included time slots.

According to the above configuration, since the number of time slots in the time hopping frame is increased or decreased according to the number of adjacent systems (number of users), packet collision is reduced even in asynchronous communication, and deterioration of communication quality can be suppressed.

That is, the invention according to claim 6 is
In the wireless control device according to any one of claims 1 to 5.
The control unit
When the data information is transmitted / received by the first communication method, the transmission / reception unit intercepts or intercepts information indicating that the synchronization of the data information has failed from the wireless terminal device to which the data information is received. When the reception destination of the data information is the wireless control device, the synchronization detection unit detects that the synchronization of the data information has failed.
When the synchronization of the data information fails a plurality of times, transmission / reception of the header portion including the synchronization signal of the packet information including at least a part of the data information is performed by the second communication method. It is characterized in that it is determined and the determined information is broadcast from the transmission / reception unit.

According to the above configuration, the communication method of the header part of the communication packet is switched between the first communication method and the second communication method according to the scale of the system and the density of stations, so that the success rate of synchronization of the communication packets is high. Ascending, it will be possible to realize high quality and robust wireless systems.

That is, the invention according to claim 7 is
A wireless terminal device that transmits and receives data information in an impulse wireless communication system.
A transmission / reception unit that receives information on a first communication method or a second communication method executed by the impulse wireless communication system from a wireless control device, and a transmission / reception unit.
A time hopping processing unit that performs time hopping processing of the data information by the first communication method or the second communication method based on the information is included.
The time hopping processing unit is
In the first communication method, one frame is assigned to one bit of data information, a plurality of time slots are assigned to the one frame, and a time hopping code unique to the impulse wireless communication system is assigned. One time slot for transmitting and receiving one bit of the data information based on the column is assigned from the plurality of time slots, and the process is executed.
In the second communication method, a plurality of frames are assigned to one bit of data information, and a plurality of time slots are assigned to each frame of the plurality of frames, which is unique to the impulse wireless communication system. It is characterized in that a process of allocating one time slot for transmitting and receiving one bit of the data information is executed for each frame based on the time hopping code string of the above.

According to the above configuration, the first communication method with low redundancy and the second communication method with high redundancy can be dynamically switched according to the number of adjacent systems, so that communication suitable for the communication environment can be performed. The method can be selected. That is, even if the number of adjacent systems increases, a unique code (TH code) is used, so that it is possible to reduce the packet collision probability and improve the communication quality without adopting the band reservation method.

That is, the invention according to claim 8 is
In the wireless terminal device according to claim 7,
One bit transmitted / received in one time slot for transmitting / receiving the data information further includes a direct spread processing unit that executes a process distributed by a direct spread code string unique to the impulse wireless communication system. And.

According to the above configuration, even if the number of adjacent systems increases, the data is distributed using a unique code (DS code) different for each system, so that the probability of packet collision is reduced and the communication quality is improved. Will be possible.

That is, the invention according to claim 9 is
In the wireless terminal device according to claim 7 or 8.
When the synchronization detection unit detects that the failure to decode the data information has failed to synchronize with the header unit including the synchronization signal of the packet information composed of at least a part of the data information. Causes the transmission / reception unit to transmit information indicating that the synchronization has failed.
When the transmission / reception unit receives information including the transmission / reception of the header unit by the second communication method, the time hopping processing unit performs the time hopping processing of the header unit of the packet information. It is characterized by further including a control unit that is executed by the communication method 2 and controls the time hopping process of the payload unit of the packet information so as to be executed by the first communication method.

According to the above configuration, the communication method of the header part of the communication packet is switched between the first communication method and the second communication method according to the scale of the system and the density of stations, so that the success rate of synchronization of the communication packets is high. Ascending, it will be possible to realize high quality and robust wireless systems.

In order to solve the above problems, the invention according to claim 10 is
In an impulse wireless communication system including a wireless control device and a wireless terminal device for transmitting and receiving data information,
The wireless control device is
Based on the information transmitted from the other impulse radio communication system, the number of the other impulse radio communication systems located around the radio control device is detected, and the number of the other impulse radio communication systems is based on the number of the other impulse radio communication systems. A control unit that determines the communication method implemented in the impulse wireless communication system as the first communication method or the second communication method.
Including a transmission / reception unit that broadcasts information for executing the first communication method or the second communication method.
The wireless terminal device is
A transmission / reception unit that receives information from the wireless control device for executing the first communication method or the second communication method in the impulse wireless communication system.
Based on the above information
In the first communication method, one frame is assigned to one bit of data information, a plurality of time slots are assigned to the one frame, and a time hopping code unique to the impulse wireless communication system is assigned. One time slot for transmitting and receiving one bit of the information data based on the column is assigned from the plurality of time slots, and the process is executed.
In the second communication method, a plurality of frames are assigned to one bit of data information, and a plurality of time slots are assigned to each frame of the plurality of frames, which is unique to the impulse wireless communication system. A time hopping processing unit that executes a process of allocating one time slot for transmitting and receiving one bit of the information data for each frame based on the time hopping code string of the above.
It is characterized by including.

According to the above configuration, the first communication method with low redundancy and the second communication method with high redundancy can be dynamically switched according to the number of adjacent systems, so that communication suitable for the communication environment can be performed. The method can be selected.

According to the present invention, even if a plurality of systems are adjacent to each other, the first communication method having low redundancy and the second communication method having high redundancy can be dynamically switched, so that communication suitable for a communication environment can be performed. The method can be selected. That is, even if the number of adjacent systems increases, the communication method is switched using a code unique to the system (TH (Time Hopping) code and DS (Collision Spread) code), so that the band reservation method is not adopted and the communication method is asynchronously switched. It is possible to reduce the probability of packet collision and improve the communication quality.

This is an example showing a situation in which a wireless communication network in which a master station and a slave station perform impulse wireless communication are adjacent to each other. This is an example of the configuration of a transmission signal in the communication system 1 by the first communication method. This is an example of the configuration of a transmission signal in the communication system 2 by the first communication method. This is an example of the configuration of a transmission signal in the communication system 1 by the second communication method. This is an example of the configuration of a transmission signal in the communication system 2 by the second communication method. It is an example of the DS code string in the 1st communication system and the 1st communication system. This is an example of a communication packet configuration. It is a flowchart which shows an example of the outline of the operation of the communication system in Example 1. FIG. It is a flowchart which shows an example of the outline of the hardware composition of a slave station and a master station in Example 1. FIG. It is a flowchart which shows an example of the outline of the operation of the communication system in Example 2. It is a flowchart which shows an example of the outline of the hardware composition of a slave station and a master station in Example 2. FIG. It is a drawing for demonstrating the prior art.

Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings. First, with reference to FIG. 1, an arrangement example of two impulse wireless communication networks using a time division access control (TDMA (Time Division Multiple Access)) method will be described.

FIG. 1 is an example of an assumed arrangement of an impulse wireless communication system. There are at least two impulse radio communication systems in the area of the impulse radio communication system of FIG. In FIG. 1, the service area 3 of the impulse wireless communication system 1 and the service area 5 of the impulse wireless communication system 2 are in contact with each other. Outside the service area 3 of the impulse wireless communication system 1, there is an interference range 4 which is a range in which the radio wave of the master station of the impulse wireless communication system 1 can reach. Similarly, outside the service area 5 of the impulse wireless communication system 2, there is an interference range 6 which is a range in which the radio wave of the master station of the impulse wireless communication system 2 can reach.

Therefore, the master station 51 or the slave station of the wireless communication system 2 existing in the interference range 4 of the wireless communication system 1 may be affected by the radio wave of the impulse wireless communication system 1, and the interference of the impulse wireless communication system 2 may occur. The master station 31 or slave station of the impulse radio communication system 1 existing in the range 6 may be affected by the radio waves of the radio communication system 2. In such a case, the master station or slave station of a system within the interference range of another system may not be able to accurately transmit and receive communication data.

Although FIG. 1 shows a case where the service area 3 of the impulse wireless communication system 1 and the service area 5 of the impulse wireless communication system 2 are in contact with each other, the service area 3 and the service area 5 may overlap with each other. In addition, the service areas of three or more impulse wireless communication systems may be in contact with each other or overlap with each other.

Each impulse radio communication system is composed of one master station and at least one slave station. Since the master station broadcasts the beacon signal including the communication control information to the slave station in the impulse wireless communication system and controls the communication timing of all the slave stations, the communication data in the impulse wireless communication system collides. (Time division access control (TDMA (Time Division Multiple Access)) method).

Next, with reference to FIGS. 2 to 6, the communication method of the master station and the slave station in each system will be described.

The master station and slave station in each system are equipped with two types of communication methods described in detail below. Both communication methods use time hopping (TH: Time Hopping) coding in which the transmission timing of the transmission signal is delayed based on the code sequence unique to each system, and the time hopping information data is unique to each system. Direct spread (DS: Direct Spread) coding is performed based on another code sequence, and then it is converted into an impulse train and transmitted.

<First communication method>
2 and 3 show an outline of coding of a transmission signal based on the first communication method. Here, the stations in the impulse wireless communication system 1 (hereinafter, abbreviated as “system 1”) and the impulse wireless communication system 2 (hereinafter, abbreviated as “system 2”) transmit the information data “1010”, respectively. The generated image of the transmission signal in the case is shown.

FIG. 2 is a diagram showing an outline of coding by a first communication method performed by a master station and a slave station in the system 1.

First, TH (Time Hopping) coding is performed on the information data. Here, one time hopping frame composed of four time slots is assigned to one bit of information data.

That is, the transmission period of 1 bit is divided into 4 time slots, and the information of 1 bit is expressed by using a time hopping frame composed of the divided 4 time slots.

For the time slot used in one time hopping frame, the time slot is selected based on the system-specific time hopping sequence (for example, the time hopping sequence of the system 1 is (0, 1, 2, 3)). ing.

For example, since the time hopping series of the system 1 is (0, 1, 2, 3), the data "1" which is the head data of the information data "1010" is the data at the head of the time hopping series (). Time slot 0 corresponding to 0) is assigned.

Similarly, since the time hopping series of the system 1 is (0, 1, 2, 3), the second data of the time hopping series is the second data for "0" which is the second data of the information data "1010". The time slot 1 corresponding to (1) is assigned.

Next, the time slot 2 corresponding to (2), which is the third data in the time hopping series, is assigned to "1", which is the third data of the information data "1010" of the system 1.

Next, the time slot 3 corresponding to (3), which is the fourth data in the time hopping series, is assigned to "0", which is the fourth data of the information data "1010" of the system 1.

Next, DS (Direct Spread) coding is performed on the information data assigned to each time slot in each time hopping frame.

DS coding will be described with reference to FIG.

In this embodiment, the DS coded data for the information data “1” uses data that is cyclically shifted to the right by a predetermined number of bits by each system based on “11010100”.

For example, if the number of cyclic shift bits for the system 1 is set to 0, the DS coded data for the information data "1" used in the system 1 becomes "11010100".

Further, when the number of cyclic shift bits for the system 2 is set to 1, the DS coded data for the information data “1” used in the system 2 becomes “01101010”.

Further, although not described in detail in this embodiment, when there are a plurality of adjacent systems and there is a system 8, if the number of cyclic shift bits for the system 8 is set to 7, the information data "1" used in the system 8 is set. The DS coded data for "" is "101001001".

Similarly, in the present embodiment, the DS coded data for the information data “0” uses data that is cyclically shifted to the right by a predetermined number of bits by each system based on “00101011”. That is, the DS coded data for the information data "1" and the DS coded data for the information data "0" are different.

For example, if the number of cyclic shift bits for the system 1 is set to 0, the DS coded data for the information data “0” used in the system 1 becomes “00101011”.

Further, when the number of cyclic shift bits for the system 2 is set to 1, the DS coded data for the information data “0” used in the system 1 becomes “10010101”.

In the system 1 of FIG. 2, the same DS coded data “11010100” is assigned to the first data “1” and the third data “1” of the information data “1010”.

Specifically, referring to the system 1 of FIG. 2, since the time slot 0 is assigned to the first data "1" of the information data "1010" by TH coding, the position of the time slot 0 Is assigned the DS coded data "11010100". Since the time slot 2 is assigned to the third data "1" of the information data "1010" by TH coding, the DS coded data "11010100" is assigned at the position of the time slot 2.

Similarly, in the system 1 of FIG. 2, the same DS coded data “00101011” is assigned to the second data “0” and the fourth data “0” of the information data “1010”. Be done.

Specifically, referring to the system 1 of FIG. 2, since the time slot 1 is assigned to the second data “0” of the information data “1010” by TH coding, the position of the time slot 1 Is assigned the DS coded data "00101011". Since the time slot 3 is assigned to the fourth data "0" of the information data "1010" by TH coding, the DS coded data "00101011" is assigned at the position of the time slot 3.

Finally, an impulse signal is generated at a position representing "1" of the DS coded data, the DS coded data is converted into an impulse signal string, and the information data is transmitted.

Further, on the receiving side of this communication method, the information data can be decoded based on the DS code peculiar to the own system of the received signal obtained by converting the impulse signal string into the digital signals of "1" and "0".

As described above, according to this communication method, it is possible to reduce the possibility of collision of communication signals of stations in adjacent systems that perform communication operations asynchronously.

Next, the coding of information data using the first communication method in the system 2 will be described with reference to FIGS. 3 and 6. The difference from the system 1 is that the TH coded data and the DS coded data are different.

Specifically, the TH coded data of the system 2 is (2, 0, 3, 1), the DS coded data for the information data "1" is (01101010), and the DS code for the information data "0". The conversion data is (10010101). Therefore, the transmission timing of the transmission pulse signal of the system 2 is different from the transmission timing of the transmission pulse signal of the system 1. (Refer to the timing of the transmission pulse signal in FIG. 1 and the timing of the transmission pulse signal in FIG. 2).

Although the TH coded data and the DS coded data are values unique to each system, the values in the sequence of numbers in the coded data are not limited to the values of this embodiment.

FIG. 3 is a diagram showing an outline of coding by the first communication method performed by the master station and the slave station in the system 2.

First, TH (Time Hopping) coding is performed on the information data. Here, one time hopping frame composed of four time slots is assigned to one bit of information data.

That is, the transmission period of 1 bit is divided into 4 time slots, and 1 bit of information is expressed by using one time hopping frame composed of the divided 4 time slots.

The time slot used in one time hopping frame selects the time slot based on the system-specific time hopping sequence (system 2 (2,0,3,1)).

For example, since the time hopping sequence of the system 2 is (2,0,3,1), the data at the beginning of the information data "1010" is the data at the beginning of the time hopping series for "1" (2,0,3,1). Time slot 2 is assigned corresponding to 2).

Similarly, time slot 0 is assigned to "0", which is the second data of the information data "1010", corresponding to (0), which is the second data of the time hopping series.

Next, the time slot 3 is assigned to "1", which is the third data of the information data "1010", corresponding to (3), which is the third data of the time hopping series.

Next, the time slot 1 is assigned to "0", which is the fourth data of the information data "1010", corresponding to (1), which is the fourth data of the time hopping series.

Then, DS (Direct Spread) coding is performed on the information data assigned to each time slot in each time hopping frame.

Next, DS coding will be described with reference to FIG.

In this embodiment, the DS coded data for the information data “1” uses data that is cyclically shifted to the right by a predetermined number of bits by each system based on “11010100”.

For example, if the number of cyclic shift bits for the system 2 is set to 1, the DS coded data for the information data “1” used in the system 2 becomes “01101010”. (See the DS coded data corresponding to system 2 in FIG. 6)

Similarly, in this embodiment, the DS coded data for the information data “0” uses data that is cyclically shifted to the right by a predetermined number of bits by each system based on “00101011”. Therefore, the DS coded data for the information data "1" and the DS coded data for the information data "0" are different.

When the number of cyclic shift bits for the system 2 is set to 1, the DS coded data for the information data “0” used in the system 2 becomes “10010101”.

In the system 2 of FIG. 3, the same DS coded data “01101010” is assigned to the first data “1” and the third data “1” of the information data “1010”.

Specifically, referring to FIG. 3, since the time slot 2 is assigned to the first data "1" of the information data "1010" by TH coding, the DS coding is performed at the position of the time slot 2. The data "01101010" is assigned. Since the time slot 3 is assigned to the third data "1" of the information data "1010" by TH coding, the DS coded data "01101010" is assigned at the position of the time slot 3.

Similarly, in the system 2 of FIG. 3, the same DS coded data “10010101” is assigned to the second data “0” and the fourth data “0” of the information data “1010”. Be done.

However, since the time slot 0 is assigned to the second data "0" of the information data "1010" by TH coding, the DS coded data "10010101" is assigned at the position of the time slot 0. Since the time slot 1 is assigned to the fourth data "0" of the information data "1010" by TH coding, the DS coded data "10010101" is assigned at the position of the time slot 1.

Finally, an impulse signal is generated at a position representing "1" of the DS-encoded data, converted into an impulse signal string, and information data is transmitted.

Further, on the receiving side of this communication method, the information data can be decoded based on the DS code peculiar to the own system of the received signal obtained by converting the impulse signal string into a digital signal consisting of "1" and "0".

As described above, according to this communication method, even if the communication signals of stations in adjacent systems that perform communication operations asynchronously overlap, the possibility of collision can be reduced.

<Second communication method>
4 and 5 show an outline of coding of a transmission signal based on the second communication method. Here, the generation image of the transmission signal when the stations in the system 1 and the system 2 each transmit the information data of "10" is shown.

FIG. 4 is a diagram showing an outline of coding by a second communication method performed by a master station and a slave station in the system 1.

First, TH (Time Hopping) coding is performed on the information data. Here, four time hopping frames are assigned to one bit of information data.

That is, the transmission period of 1 bit is divided into 4 time hopping frames, each time hopping frame is divided into 4 time slots, and 1 bit is used for each 1 time hopping frame composed of the divided 4 time slots. Send information repeatedly.

Therefore, in the second communication method, one bit of information data is repeatedly transmitted four times.

The time slot used in each time hopping frame selects the time slot based on the system-specific time hopping sequence (for example, system 1 (0, 1, 2, 3)). This time hopping series is commonly used in the first communication method and the second communication method. However, different time hopping sequences can be used between the first communication method and the second communication method.

Specifically, referring to FIG. 4, the time slot of the first time hopping frame assigned to the information data “1” of the system 1 is the first in the time hopping series (0, 1, 2, 3). Time slot 0 is assigned corresponding to the data "0". Therefore, the time slot 0 of the first time hopping frame assigned to the information data “1” is “1”.

Similarly, the time slot of the second time hopping frame assigned to the information data "1" of the system 1 is set to "1" which is the second data of the time hopping series (0, 1, 2, 3). Correspondingly, time slot 1 is assigned. Therefore, the time slot 1 of the second time hopping frame becomes "1".

Next, the time slot of the third time hopping frame assigned to the information data "1" of the system 1 is set to "2" which is the third data of the time hopping series (0, 1, 2, 3). Correspondingly, time slot 2 is assigned. Therefore, the time slot 2 of the third time hopping frame becomes "1".

Next, the time slot of the fourth time hopping frame assigned to the information data "1" of the system 1 is set to "3" which is the fourth data of the time hopping series (0, 1, 2, 3). Correspondingly, time slot 3 is assigned. Therefore, the time slot 3 of the fourth time hopping frame becomes "1".

As described above, in the second communication method, one bit of information data is repeatedly transmitted four times in different time slots for each time hopping frame. Therefore, as compared with the first communication method, the second communication method has a configuration in which the probability that the information data is interfered with by another system can be reduced. For example, even if the data in one or more time slots is interfered with and cannot be decoded, the original data can be reproduced from the data in other time slots, so that the communication method is resistant to interference. ing.

Next, TH coding of the information data “0” next to the information data “1” of the system 1 will be described.

The time slot of the first time hopping frame assigned to the information data "0" of the system 1 corresponds to "0" which is the first data of the time hopping series (0, 1, 2, 3). Time slot 0 is assigned. Therefore, the time slot 0 of the first time hopping frame assigned to the information data “0” is “0”.

Similarly, the time slot of the second time hopping frame assigned to the information data "0" of the system 1 is set to "1" which is the second data of the time hopping series (0, 1, 2, 3). Correspondingly, time slot 1 is assigned. Therefore, the time slot 1 of the second time hopping frame becomes "0".

Next, the time slot of the third time hopping frame assigned to the information data "0" of the system 1 is set to "2" which is the third data of the time hopping series (0, 1, 2, 3). Correspondingly, time slot 2 is assigned. Therefore, the time slot 2 of the third time hopping frame becomes “0”.

Next, the time slot of the fourth time hopping frame assigned to the information data "0" of the system 1 is set to "3" which is the fourth data of the time hopping series (0, 1, 2, 3). Correspondingly, time slot 3 is assigned. Therefore, the time slot 3 of the fourth time hopping frame becomes “0”.

As described above, in the second communication method, as with the information data “1”, one bit of the information data “0” is repeatedly transmitted four times in a different time slot for each time hopping frame.

Next, DS coding will be described with reference to FIGS. 4 and 6.

In the present embodiment, the DS coded data for the information data "1" uses data that is cyclically shifted to the right by a predetermined number of bits by each system based on "11010100".

For example, if the number of cyclic shift bits for the system 1 is set to 0, the DS coded data for the information data "1" used in the system 1 becomes "11010100". (See the DS coded data corresponding to system 1 in FIG. 6)
The DS coded data is data commonly used in the first communication method and the second communication method. However, the DS coded data is different for each system, and the DS coded data for the information data "1" and the DS coded data for the information data "0" are also different for each system.

Since the number of cyclic shift bits for the system 1 is 0, the DS coded data for the information data “0” used in the system 1 is “00101011”. (See the DS coded data corresponding to system 1 in FIG. 6)

In the system 1 of FIG. 4, DS coded data "11010100" is assigned to "1" which is the first data of the information data "10", and "10" which is the second data of the information data "10". DS coded data "00101011" is assigned to "0".

Therefore, the DS coded data "11010100" is assigned to the 0th time slot 0 of the first time hopping frame in the information data "1".

Similarly, the first time slot 1 of the second time hopping frame in the information data "1", the second time slot 2 of the third time hopping frame, and the third time slot of the third time hopping frame. DS coded data "11010100" is assigned to 3.

Further, the DS coded data "00101011" is assigned to the 0th time slot 0 of the first time hopping frame in "0" which is the next information data of the information data "1".

Similarly, time slot 1, which is the second time slot of the second time hopping frame within the period of the information data "0", and time slots 2, 3 which are the second time slots of the third time hopping frame. DS coded data "00101011" is assigned to the time slot 3, which is the third time slot of the third time hopping frame.

Finally, an impulse signal is generated at a position representing "1" of the DS-encoded data, converted into an impulse signal string, and information data is transmitted.

In this way, as compared with the first communication method, in the second communication method, the same information data is transmitted from different time slots of the plurality of time hopping frames as many times as the number of times of the plurality of time hopping frames. It is configured to reduce the probability of receiving interference from.

In this communication method, the information data bits are distributed in a plurality of time hopping frames on the transmitting side and transmitted, and on the receiving side, information is obtained from the correlation between the received signal in each time hopping frame and the TH code and DS code peculiar to the own system. Since the data can be decoded, the transmission speed is lower than that of the first communication method, but the communication quality can be improved.

In the above-mentioned example, the case where one bit of the information data has "1" or "0" has been described, but even when the information data bit takes multiple values, it can be encoded and decoded with the DS code. can. For example, when one bit of information data takes n (n is a positive integer of 3 or more) values, it may have a DS code string consisting of n data different for each system. Again, the differences between the systems can be obtained by cyclically shifting the DS code sequence. In the following description, the case where the information data bit has "1" or "0" will be described continuously.

Next, the coding of the information data using the second communication method in the system 2 will be described with reference to FIGS. 5 and 6. The difference from the system 1 is that the TH coded data and the DS coded data are different.

Specifically, the TH coded data of the system 2 is (2, 0, 3, 1), the DS coded data for the information data "1" is (01101010), and the DS code for the information data "0". The conversion data is (10010101). Therefore, the transmission timing of the transmission pulse signal of the system 2 is different from the transmission timing of the transmission pulse signal of the system 1. (Refer to the timing of the transmission pulse signal in FIG. 4 and the timing of the transmission pulse signal in FIG. 5).

Further, the TH coded data and the DS coded data in the same system are the same in the first communication method and the second communication method. That is, the TH coded data and the DS coded data are system-specific values and are commonly used in the first communication method and the second communication method.

FIG. 5 is a diagram showing an outline of coding by a second communication method performed by a master station and a slave station in the system 2.

First, TH (Time Hopping) coding is performed on the information data as in the system 1. Again, four hopping frames are assigned to one bit of information data.

That is, the transmission period of 1 bit is divided into 4 hopping frames, each hopping frame is divided into 4 time slots, and 1 bit of information is input for each 1 time hopping frame composed of the divided 4 time slots. Send repeatedly.

Therefore, also in the system 2, in the second communication method, one bit of information data is repeatedly transmitted four times.

The time slot used in each time hopping frame selects the time slot based on the system-specific time hopping sequence (for example, system 2 (2, 0, 3, 1)). This time hopping series is commonly used in the first communication method and the second communication method.

The time slot of the first time hopping frame assigned to the information data "1" of the system 2 corresponds to "2" which is the first data of the time hopping series (2, 0, 3, 1). Time slot 2 is assigned. Therefore, the time slot 2 which is the third time slot in the first time hopping frame assigned to the information data “1” becomes “1”.

Similarly, the time slot of the second time hopping frame assigned to the information data "1" of the system 2 is set to "0" which is the second data of the time hopping series (2, 0, 3, 1). Correspondingly, time slot 0 is assigned. Therefore, the time slot 0 of the second time hopping frame becomes "1".

Next, the time slot of the third time hopping frame assigned to the information data "1" of the system 2 is set to "3" which is the third data of the time hopping series (2, 0, 3, 1). Correspondingly, time slot 3 is assigned. Therefore, the time slot 3 of the third time hopping frame becomes "1".

Next, the time slot of the fourth time hopping frame assigned to the information data "1" of the system 2 is set to "1" which is the fourth data of the time hopping series (2, 0, 3, 1). Correspondingly, time slot 1 is assigned. Therefore, the time slot 2 of the second time hopping frame becomes "1".

As described above, in the second communication method, one bit of information data is repeatedly transmitted four times in different time slots for each time hopping frame.

Similarly, the information data "0" next to the information data "1" of the system 2 is TH-encoded. Detailed explanation will be omitted.

Next, the DS coding of the second communication system in the system 2 will be described with reference to FIGS. 5 and 6.

In this embodiment, the DS coded data for the information data “1” uses data that is cyclically shifted to the right by a predetermined number of bits by each system based on “11010100”.

For example, if the number of cyclic shift bits for the system 2 is set to 1, the DS coded data for the information data “1” used in the system 2 becomes “01101010”. (See the DS coded data corresponding to system 2 in FIG. 6)

Since the number of cyclic shift bits for the system 2 is 1, the DS coded data for the information data “0” used in the system 2 is “10010101”. (See the DS coded data corresponding to system 2 in FIG. 6)

The DS coded data is data commonly used in the first communication method and the second communication method, and the DS coded data for the information data "1" and the DS coded data for the information data "0". Is different for each system.

In the system 2 of FIG. 5, DS coded data “01101010” is assigned to “1” which is the first data of the information data “10”, and “10” which is the second data of the information data “10”. DS coded data "10010101" is assigned to "0".

Therefore, the DS coded data "01101010" is assigned to the time slot 2, which is the third time slot of the first time hopping frame in the information data "1".

Similarly, time slot 0, which is the first time slot of the second time hopping frame in the information data "1", time slot 3, the third time, which is the fourth time slot of the third time hopping frame. DS coded data "01101010" is assigned to the time slot 1, which is the second time slot of the hopping frame.

Further, the DS coded data "10010101" is assigned to the time slot 2 which is the third time slot of the first time hopping frame in the information data "0" next to the information data "1".

Similarly, time slot 0, which is the first time slot of the second time hopping frame in the information data "0", time slots 3, and fourth times, which are the fourth time slots of the third time hopping frame. DS coded data "10010101" is assigned to the time slot 1, which is the second time slot of the hopping frame.

Finally, an impulse signal is generated at a position representing "1" of the DS-encoded data, converted into an impulse signal string, and information data is transmitted.

In the second communication method, the information data bits are distributed and transmitted in a plurality of time hopping frames on the transmitting side, and the correlation between the received signal in each time hopping frame and the TH code and DS code peculiar to the own system on the receiving side. Since the information data can be decoded from the above, the transmission speed is lower than that of the first communication method, but the communication quality can be improved.

In this embodiment, the above two types of communication methods can be switched according to the communication environment. For example, the communication environment includes the number of adjacent systems, and the communication method can be switched based on the number of adjacent systems.

For example, by intercepting a beacon signal transmitted by another system with this system, the number of other systems existing in the vicinity can be detected as the number of adjacent systems.

Then, for example, when the number of adjacent systems is less than or equal to a predetermined number, the first communication method is used, and when the number of adjacent systems exceeds a predetermined number, the second communication method is used. It is possible to select a communication method suitable for the communication environment. The predetermined number can be a predetermined number in the system. It can also be set to a different value for each system.

Further, in the present embodiment, the number of time slots in the time hopping frame in the time hopping of the second communication method can be changed according to the communication environment.

For example, if the number of detected adjacent systems increases, the number of time slots in the time hopping frame can be increased, and if the number of detected adjacent systems decreases, the number of time slots in the time hopping frame can be decreased. You can dynamically change the number of time slots in a time hopping frame. In this case, the TH coded data can also be increased or decreased in accordance with the increase or decrease in the number of time slots.

For example, when the number of time slots in the time hopping frame is increased to 5, the data constituting the TH code sequence is also changed to 5 (for example, (0, 1, 2, 3, 4)). The TH code pattern can be changed for each system.

Further, for example, when the number of time slots in the time hopping frame is reduced to 3, the data constituting the TS code sequence is also changed to 3 (for example, (0, 1, 2)) for each system. The TS code pattern can be changed to.

As an example, the number of time slots in the time hopping frame may be the same as the number of detected adjacent systems, the number of detected adjacent systems + n (n is an integer and the system can be set to an arbitrary value), or any other value. Corresponding pattern may be used.

The data rate is improved and recovered by selecting the optimum TH code pattern according to the increase or decrease in the number of detected adjacent systems and adjusting the number of time slots in the time hopping frame to the minimum, as well as the communication error rate. It is possible to suppress the deterioration of communication quality.

<Example 1>
Hereinafter, the operation of the system in the first embodiment will be specifically described with reference to the flowchart of FIG. The processing procedure of FIG. 8 in the station is performed according to a program stored in a ROM (Read Only Memory) (for example, a part of the storage unit 950 in FIG. 9) in the CPU (Central Processing Unit) of the station. The control unit 940 and the signal processing unit 930) in FIG. 9 execute the operation.

It should be noted that some or all of the following processing procedures can be executed by hardware such as DSP and ASIC. However, in this embodiment, a case where the CPU executes according to the ROM program will be described.

In step S801, the master station of the system intercepts the beacon signal broadcast by the master station of the other system, detects another adjacent system, and counts the number of other adjacent systems. Next, the process proceeds to step S802.

In step S802, it is determined whether or not the count number of other adjacent systems is equal to or greater than a predetermined number (n: positive integer). The value of n can be set for each system and can be any positive integer.

If the count number of the other adjacent systems is n or more (step S802: YES), the process proceeds to step S803, and if the count number of the other adjacent systems is less than n (step S802: NO), the step is performed. Proceed to S805.

In step S803, the master station notifies the slave station that the slave station is transmitting and receiving in the system by the first communication method by broadcasting the beacon signal. In this case, it is determined that there is little interference between the systems because the number of adjacent systems is small. Next, the process proceeds to step S804.

In step S804, the slave station that has received the beacon signal indicating that transmission / reception is performed in the system by the first communication method is TH for the information data used for transmission based on the TH sequence peculiar to the system when transmitting the information data. Encoding is performed, then DS coding is performed based on the system-specific DS series (FIG. 6), and the DS-encoded data is converted into an impulse signal sequence and transmitted.

When the slave station that receives the beacon signal receives the information data, it performs DS decoding of the received impulse signal sequence based on the system-specific DS series (FIG. 6), and the data consists of "1" and "0". Decrypt into columns, then extract information data from the time slot based on the system-specific TH sequence and decode the transmitted information data. Adjacent systems can operate asynchronously. Further, the same process is executed in the base station as well. Next, the process proceeds to step S807.

In step S805, the master station notifies the slave station that the slave station is transmitting and receiving in the system by the second communication method by broadcasting the beacon signal. In this case, it is determined that there is a lot of interference between the systems because the number of adjacent systems is large. Next, the process proceeds to step S806.

In step S806, the slave station that receives the beacon signal indicating that transmission / reception is performed in the system by the second communication method receives the beacon signal indicating that the transmission / reception is performed in the system, and when the information data is transmitted, each bit of the information data used for transmission based on the TH sequence peculiar to the system. TH coding is performed by allocating multiple time hopping frames to the system, then DS coding is performed based on the system-specific DS series (FIG. 6), and the DS-coded data is converted into an impulse signal sequence. Send. That is, one bit of information data is transmitted a plurality of times in different time slots of a plurality of time hopping frames assigned to the one bit.

In this case, the number of time slots in the time hopping frame in TH coding can be increased or decreased according to the number of adjacent systems counted in step S801. For example, when the number of time slots in the time hopping frame is changed to n (n: positive integer), the data constituting the TH code sequence is also changed to n corresponding to the number of time slots, and the system The TH code pattern can be changed every time. The correspondence between the number of time slots and the number of adjacent systems can be set arbitrarily. In the first embodiment, the case where the number of time slots in the time hopping frame is set to four is described.

When the slave station that receives the beacon signal receives the information data, it performs DS decoding of the received impulse signal sequence based on the system-specific DS series (FIG. 6), and the data consists of "1" and "0". Decoding into columns, then extracting one bit of information data from a plurality of time slots based on the system-specific TH sequence, determining the value of the information data, and decoding the transmitted information data. Further, the same process is executed in the base station as well. Adjacent systems can operate asynchronously. Next, the process proceeds to step S807.

In step S807, it is confirmed whether or not there is information data to be transmitted to the station. If there is information data to be transmitted to the station (step S807: YES), the process proceeds to step S801, and if there is no information data to be transmitted to the station (step S807: NO), the process ends.

Next, FIG. 9 shows the hardware configuration of the master station which is an information control device or the slave station which is an information terminal device. As an example, since the master station and the slave station may include the same hardware configuration, in FIG. 9, the master station and the slave station will be described together as the information communication device 900.

The information communication device 900 transmits / receives wireless communication data between the antenna unit 910 that transmits / receives wireless communication data to / from another information communication device and the antenna unit 910, converts the wireless communication data into digital data, or digitally. A control unit that transmits / receives information data between a transmission / reception unit 920 that converts data into wireless communication data, a signal processing unit 930 that transmits / receives information data that is digital data between the transmission / reception unit 920, and a signal processing unit 930. 940 and a storage unit 950 are included.

The signal processing unit 930 includes a TH processing unit 931 that executes time hopping processing and a DS processing unit 932 that executes direct spread processing.

The transmission / reception unit 920 includes an impulse processing unit 921 that digitizes information data or digitizes the pulsed wireless communication data.

The TH processing unit 931 executes signal processing of the first communication method and the second communication method.

When information data is transmitted by the first communication method, one time hopping frame composed of four time slots is assigned to one bit of the information data. The time slots used in the time hopping frame are based on the system's unique time hopping sequence (eg, (0, 1, 2, 3) in system 1 and (2, 0, 3, 1) in system 2). It is determined.

When the information data is transmitted by the second communication method, four time hopping frames composed of four time slots are assigned to one bit of the information data, and one bit is distributed to four. The time slot used in each time hopping frame is based on the system's unique time hopping sequence (eg, (0, 1, 2, 3) for system 1 and (2, 0, 3, 1) for system 2). ,It is determined. The number of time slots assigned to each time hopping frame can be dynamically changed, and the number of data constituting the time hopping series can be dynamically changed accordingly.

The time slot of the first time hopping frame assigned to the information data "1" of the system 1 corresponds to the first "0" of the time hopping series (0, 1, 2, 3) peculiar to the system 1. Then, time slot 0 is assigned. Similarly, time slot 1 is assigned to the time slot of the second time hopping frame, time slot 2 is assigned to the time slot of the third time hopping frame, and the time slot of the third time hopping frame is assigned. Time slot 3 is assigned.

The time slot of the first time hopping frame assigned to the information data "1" of the system 2 corresponds to the first "2" of the time hopping series (2, 0, 3, 1) peculiar to the system 2. Then, the time slot 2 is assigned. Similarly, time slot 0 is assigned to the time slot of the second time hopping frame, time slot 3 is assigned to the time slot of the third time hopping frame, and the time slot of the third time hopping frame is assigned. Time slot 1 is assigned.

The DS processing unit 932 executes the same processing in the first communication method and the second communication method.

However, DS processing is performed based on the system's unique direct spread sequence. (See Fig. 6)

A DS code (11010100) is assigned to the information data "1" of the system 1, and a DS code (00101011) is assigned to the information data "0". (See Fig. 6)

A DS code (01101010) is assigned to the information data "1" of the system 2, and a DS code (10010101) is assigned to the information data "0". (See Fig. 6)

For the received data, the information data "1" or "0" is generated from the TH code string and the DS code string assigned to each system. Details are omitted.

The impulse processing unit 921 generates an impulse signal at a position corresponding to the data "1" in each time slot at the time of transmission, and generates data "1" at a position where the impulse signal is received at the time of reception.

The control unit 940 generates information data for transmission, and also executes data processing on the received information data based on an OS, an application, or the like.

Further, the control unit 940 counts the number of adjacent systems, determines whether to transmit / receive information data by the first communication method or the second communication method, and uses the determined information as a beacon signal. It also has a function to broadcast and notify each slave station. The determined information may include a TH code string and a DS code string unique to each system.

Further, the control unit 940 stores the system-specific TH code string and DS code string in the storage unit 950, and supplies the TH code string and the DS code string to the TH processing unit 931 and the DS processing unit 932 of the signal processing unit 930. ..

Further, the OS and the application program may be stored in the storage unit 950. The TH code string and the DS code string can be transmitted and stored by the communication control information included in the beacon signal of the master station, but may be written in the storage unit 950 at the time of manufacture.

According to the above-described embodiment, the first communication method with low redundancy and the second communication method with high redundancy can be dynamically switched according to the number of adjacent systems, which is suitable for a communication environment. It is possible to select the communication method. That is, even if the number of adjacent systems increases, time hopping processing and direct spread processing are performed using a code unique to each system. Therefore, the packet collision probability is reduced and the communication quality is improved without adopting the bandwidth reservation method. It will be possible to make it better.

(Example 2)
In the second embodiment, the two types of communication methods shown in the first embodiment are switched between the header portion and the payload portion of the communication packet, respectively.

In order to realize more optimal communication access control in an impulse wireless communication system in which the length of information data is short but the interference power is high (for example, an impulse wireless communication system in which stations are concentrated in a network within a communication range). In addition, the two types of communication methods shown in the first embodiment can be switched between the header part and the payload part of the communication packet, respectively.

First, a configuration example of a communication packet will be described with reference to FIG. 7. Communication packets are roughly divided into a header part and a payload part, and the header part further includes a synchronization signal part for matching transmission / reception timing between a transmitting station and a receiving station, a transmitting station identifier (for example, a transmitting station number), and a destination. It is composed of a communication control data unit including communication control data such as a station identifier (for example, a destination station number) and a packet length. User data according to the application is transmitted in the payload part.

If the length of the information data is short, the communication packet is also short, so there is a high possibility that the interference time of the user question will be short. Therefore, it may be possible to avoid interference even if the first communication method is used and the number of time slots for time hopping is reduced.

However, if the interference power is high, synchronization cannot be established due to the influence of the interference power in the header part, which is required to have a detection rate 10 times or more better than that of the payload part, and communication may fail. In order to reduce communication failures in the header section, the success rate of synchronization can be increased by switching the modulation / demodulation method of the header section to the second communication method when synchronization fails a plurality of times. Further, if the first communication method is used for the payload unit, the interference time of the payload unit with other systems is shortened, so that optimum communication access control can be realized.

Hereinafter, the operation of the system in the second embodiment will be specifically described with reference to the flowchart of FIG. The processing procedure of FIG. 10 in the station follows the program in which the CPU of the station is stored in the ROM (for example, a part of the storage unit 1150 of FIG. 11), and the CPU (for example, the control unit 1140 and the signal processing unit 1130 of FIG. 11) are in accordance with the program. ) Executes.

It should be noted that some or all of the following processing procedures can be executed by hardware such as DSP and ASIC. However, in this embodiment, a case where the CPU executes according to the ROM program will be described.

In step S1001, the master station of the system initializes the flag of the number of synchronization failures of the communication packet with the slave station to "0" (the flag of the number of synchronization failures is stored in the storage unit 1150 of the master station). Then, the process proceeds to step S1002.

In step S1002, it is determined whether or not the number of synchronization failures is equal to or greater than a predetermined value n (a positive integer). The value of n can be set for each system and can be any positive integer. Further, the master station can dynamically change the value of n based on the synchronization failure probability of the communication packet with the slave station.

If the number of synchronization failures is equal to or greater than the predetermined value n (positive integer) (step S1002: YES), the process proceeds to step S1008, and if the number of synchronization failures is less than the predetermined value n (positive integer) (step S1002). : NO) proceeds to step S1003.

In step S1003, the master station notifies the slave station that the slave station is transmitting and receiving in the system by the first communication method by broadcasting the beacon signal. That is, since the number of synchronization failures is less than a predetermined value n (a positive integer), the first communication method with less redundancy is used.

In step S1004, the slave station that has received the beacon signal indicating that transmission / reception is performed in the system by the first communication method transmits / receives using the first communication method in both the header part and the payload part of the communication packet. ..

In step S1005, the master station intercepts and determines whether or not the communication of the communication packet transmitted / received by the first communication method has failed. Judgment as to whether or not communication of a communication packet has failed can be made based on whether or not the master station has intercepted information indicating that reception synchronization has failed from the station that is the destination of the communication packet. .. However, when the master station is the destination of the communication packet, the master station receives the information indicating that the synchronization has failed and determines. The synchronization failure can be determined by each station based on the error signal of the synchronization detection unit 1160 of each station, and each station can transmit information indicating that the synchronization has failed.

If the communication packet synchronization fails (step S1005: YES), the process proceeds to step S1006, and if the communication packet synchronization succeeds (step S1005: YES), the process proceeds to step S1007.

In step S1006, the master station increments the flag indicating the number of synchronization failures. The flag indicating the number of synchronization failures can be stored in the storage unit 1150 of the master station.

In step S1008, the master station broadcasts a beacon signal to the slave station that the header portion of the communication packet transmits / receives using the second communication method and the payload portion of the communication packet transmits / receives using the first communication method. By doing so, the slave station is notified. That is, when the number of synchronization failures is equal to or greater than a predetermined value n (a positive integer), the master station determines that interference frequently occurs in the synchronization signal section of the header section, and the header section has high redundancy. The second communication method is adopted.

In step S1009, the slave station that has received the beacon signal indicating that transmission / reception within the system is performed using the second communication method in the header part of the communication packet and the first communication method in the payload part of the communication packet Based on the beacon signal, the communication method can be switched between the header part and the payload part of the communication packet to perform transmission and reception. Next, the process proceeds to step S1010.

In step S1010, the master station intercepts and determines whether or not the communication of the communication packet transmitted / received by mixing the first communication method and the second communication method has failed. Judgment as to whether or not communication of a communication packet has failed is made based on whether or not the master station has intercepted information (for example, an ACK signal) indicating that reception has been successful from the station that is the destination of the communication packet. can do. However, if the master station is the destination of the communication packet, the master station itself can determine.

If the communication of the communication packet fails (step S1010: YES), the process proceeds to step S1011. If the communication of the communication packet succeeds (step S1010: NO), the communication failure flag is initialized and the process proceeds to step S1007. move on.

In step S1011, the master station determines whether or not the number of times the communication of the communication packet has failed exceeds a predetermined value. The master station stores in the storage unit 1150 a flag indicating a communication failure when the second communication method is adopted for transmission / reception of the header unit. The communication failure flag is also provided to prevent the system from deadlocking.

If the communication failure flag when the second communication method is adopted for transmission / reception of the header portion exceeds a predetermined value (step S1011: YES), the communication failure flag is initialized and the process proceeds to step S1007.

If the second communication failure flag when the second communication method is adopted for transmission / reception of the header portion does not exceed a predetermined value (step S1011: NO), the communication failure flag is incremented and the process proceeds to step S1008. ..

In step S1007, it is determined whether or not there are remaining communication packets to be transmitted. If the communication packet to be transmitted remains (step S1007: YES), the process proceeds to step S1001, and if the communication packet to be transmitted does not remain (step S1007: NO), the process ends.

If the number of communication failures when the second communication method is adopted only for the header part exceeds a predetermined value, communication packets are transmitted / received to the header part and the payload part using the second communication method. You can also do it.

As described above, in the second embodiment, in order to reduce the communication failure in the header portion. When synchronization fails multiple times at the receiving station, the success rate of synchronization can be increased by switching the modulation / demodulation method of the header portion to the second communication method. Further, if the first communication method is used in the payload unit, the interference time of the payload unit with other systems is shortened, so that optimum communication access control can be realized.

Next, FIG. 11 shows the hardware configuration of the master station which is the information control device or the slave station which is the information terminal device according to the second embodiment. As an example, since the master station and the slave station may include the same hardware configuration, in FIG. 11, the master station and the slave station will be collectively described as the information communication device 1100.

The information communication device 1100 transmits / receives wireless communication data between the antenna unit 1110 that transmits / receives wireless communication data to / from another information communication device and the antenna unit 1110, converts the wireless communication data into digital data, or digitally. A control unit that transmits / receives information data between the transmission / reception unit 1120 that converts data into wireless communication data, the signal processing unit 1130 that transmits / receives information data that is digital data between the transmission / reception unit 1120, and the signal processing unit 1130. 1140 and storage unit 1150 are included.

The signal processing unit 1130 includes a TH processing unit 1131 that executes time hopping processing and a DS processing unit 1132 that executes direct spread processing.

The transmission / reception unit 1120 includes an impulse processing unit 1121 that converts information data into impulses or digitizes the pulsed wireless communication data.

The TH processing unit 1131 executes signal processing of the first communication method and the second communication method.

While the number of synchronization failures in the header part of the communication packet does not exceed the predetermined value, the TH processing unit 1131 processes the header part by the first communication method, and when the number of synchronization failures exceeds the predetermined value, TH processing is performed. The unit 1131 processes the header unit by the second communication method. Details of the signal processing of the first communication method and the second communication method will be omitted.

The DS processing unit 1132 executes the same processing in the first communication method and the second communication method.

However, DS processing is performed based on the system's unique direct spread sequence (see Figure 6). Details of signal processing will be omitted.

The impulse processing unit 1121 generates an impulse signal at a position corresponding to the data "1" in each time slot at the time of transmission, and generates data "1" at a position where the impulse signal is received at the time of reception.

The control unit 1140 counts the number of times synchronization fails in the header unit, determines whether the header unit of the communication packet is transmitted / received by the first communication method or the second communication method, and is determined. It also has a function of broadcasting information as a beacon signal and notifying each slave station. The determined information may include a TH code string and a DS code string.

In addition, it generates information data for transmission, and also executes data processing on the received information data based on the OS, application, or the like.

Further, the storage unit 1150 stores the TH code string and the DS code string unique to the system, and the TH code string and the DS code string are supplied to the TH processing unit 1131 and the DS processing unit 1132 of the signal processing unit 1130, respectively.

Further, the OS and the application program may be stored in the storage unit 1150. The TH code string and the DS code string can be transmitted and stored by the communication control information included in the beacon signal of the master station, but may be written in the storage unit 1150 at the time of manufacture.

According to the above-described embodiment, the communication method of the header portion of the communication packet is set according to the degree of station congestion (determined by the number of synchronization detection failures) for a system in which stations may be concentrated. Since it is possible to dynamically switch between the first communication method and the second communication method, the success rate of synchronization of communication packets is increased, and a high-quality and robust wireless system can be realized.

Although various examples have been described above, some or all of these examples can be combined into new examples.

The present invention is extremely useful in the wireless communication of an impulse wireless communication system when a plurality of impulse wireless communication systems are adjacent to each other.

1 ... Impulse wireless communication system 1
2 ... Impulse wireless communication system 2
3 ... Service area of impulse wireless communication system 1 4 ... Range of radio waves of the master station of impulse wireless communication system 1 5 ... Service area of impulse wireless communication system 2 6 ... Impulse wireless communication system 2 Range of radio waves of the master station 31, 51 ... Master station 900, 1100 ... Information communication device 910, 1110 ... Antenna unit 920, 1120 ... Transmission / reception unit 921, 1121 ... Impulse processing unit 930, 1130 ... Signal processing unit 931, 1131 ... TH processing unit 932, 1132 ... DS processing unit 940, 1140 ... Control unit 950, 1150 ... Storage unit 1160 ... Synchronous detection unit

Claims (10)

A wireless control device that sends and receives data information in an impulse wireless communication system.
Based on the information transmitted from the other impulse radio communication system, the number of the other impulse radio communication systems located around the radio control device is detected, and the number of the other impulse radio communication systems is based on the number of the other impulse radio communication systems. A control unit that determines the communication method implemented in the impulse wireless communication system as the first communication method or the second communication method.
A transmission / reception unit that broadcasts information for executing the first communication method or the second communication method.
In the first communication method, one frame is assigned to one bit of data information, a plurality of time slots are assigned to the one frame, and a time hopping code unique to the impulse wireless communication system is assigned. One time slot for transmitting and receiving one bit of the data information based on the column is assigned from the plurality of time slots, and the process is executed.
In the second communication method, a plurality of frames are assigned to one bit of data information, and a plurality of time slots are assigned to each frame of the plurality of frames, which is unique to the impulse wireless communication system. A wireless control device including a time hopping processing unit that executes a process in which one time slot for transmitting / receiving one bit of data information is assigned to each frame based on the time hopping code string of the above. The control unit
The wireless control device according to claim 1, wherein the other impulse wireless communication system and the wireless control device are operated asynchronously. The one bit transmitted / received in one time slot for transmitting / receiving the data information further includes a direct spread processing unit that executes a process distributed by a direct spread code string unique to the impulse wireless communication system. The wireless control device according to claim 1 or 2. The radio control device according to claim 3, wherein the direct spread code string differs depending on the bit value of the data information. In the second communication method, the time hopping processing unit is assigned to each frame of the plurality of frames assigned to one bit of the data information in response to an increase or decrease in the number of the other impulse wireless communication systems. The wireless control device according to any one of claims 1 to 4, wherein the process of increasing or decreasing the number of included time slots is executed. The control unit
When the data information is transmitted / received by the first communication method, the transmission / reception unit intercepts or intercepts information indicating that the synchronization of the data information has failed from the wireless terminal device to which the data information is received. When the reception destination of the data information is the wireless control device, the synchronization detection unit detects that the synchronization of the data information has failed.
When the synchronization of the data information fails a plurality of times, transmission / reception of the header portion including the synchronization signal of the packet information including at least a part of the data information is performed by the second communication method. The radio control device according to any one of claims 1 to 5, wherein the determined information is broadcast from the transmission / reception unit. A wireless terminal device that transmits and receives data information in an impulse wireless communication system.
A transmission / reception unit that receives information on a first communication method or a second communication method executed by the impulse wireless communication system from a wireless control device, and a transmission / reception unit.
A time hopping processing unit that performs time hopping processing of the data information by the first communication method or the second communication method based on the information is included.
The time hopping processing unit is
In the first communication method, one frame is assigned to one bit of data information, a plurality of time slots are assigned to the one frame, and a time hopping code unique to the impulse wireless communication system is assigned. One time slot for transmitting and receiving one bit of the data information based on the column is assigned from the plurality of time slots, and the process is executed.
In the second communication method, a plurality of frames are assigned to one bit of data information, and a plurality of time slots are assigned to each frame of the plurality of frames, which is unique to the impulse wireless communication system. A wireless terminal device, characterized in that it executes a process in which one time slot for transmitting and receiving one bit of the data information is assigned to each frame based on the time hopping code string of the above. One bit transmitted / received in one time slot for transmitting / receiving the data information further includes a direct spread processing unit that executes a process distributed by a direct spread code string unique to the impulse wireless communication system. The wireless terminal device according to claim 7. When the synchronization detection unit detects that the failure to decode the data information has failed to synchronize with the header unit including the synchronization signal of the packet information composed of at least a part of the data information. Causes the transmission / reception unit to transmit information indicating that the synchronization has failed.
When the transmission / reception unit receives information including the transmission / reception of the header unit by the second communication method, the time hopping processing unit performs the time hopping processing of the header unit of the packet information. The invention according to claim 7 or 8, further comprising a control unit that is executed by the communication method of 2 and controls the time hopping process of the payload part of the packet information so as to be executed by the first communication method. Wireless terminal device. In an impulse wireless communication system including a wireless control device and a wireless terminal device for transmitting and receiving data information,
The wireless control device is
Based on the information transmitted from the other impulse radio communication system, the number of the other impulse radio communication systems located around the radio control device is detected, and the number of the other impulse radio communication systems is based on the number of the other impulse radio communication systems. A control unit that determines the communication method implemented in the impulse wireless communication system as the first communication method or the second communication method.
Including a transmission / reception unit that broadcasts information for executing the first communication method or the second communication method.
The wireless terminal device is
A transmission / reception unit that receives information from the wireless control device for executing the first communication method or the second communication method in the impulse wireless communication system.
Based on the above information
In the first communication method, one frame is assigned to one bit of data information, a plurality of time slots are assigned to the one frame, and time hopping peculiar to the impulse wireless communication system is assigned. A process is executed in which one time slot for transmitting and receiving one bit of the data information is assigned from the plurality of time slots based on the code string.
In the second communication method, a plurality of frames are assigned to one bit of data information, and a plurality of time slots are assigned to each frame of the plurality of frames, which is unique to the impulse wireless communication system. A time hopping processing unit that executes a process of allocating one time slot for transmitting and receiving one bit of the data information for each frame based on the time hopping code string of the above.
A wireless communication system characterized by including.

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