JP2003163670A - Wireless communication device and wireless communication system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve communication quality without lowering the communication rate of radio communication by avoiding and reducing the problem of the communication rate and occurrence of disconnection, etc., of communication as a result of receiving interference from external noise or another radio communication particularly from a communication system for communicating by using a wide frequency band like an FH system in a radio communication system for communicating by using a narrow frequency band like a DS system. <P>SOLUTION: A transmission-side terminal 1 is provided with transmission queues 12 and 13, radio circuits 16 and 17, and management tables 14a and 14b for managing the transmission queues which are multiplexed communication circuits. A data-reception side terminal 2 is also provided with radio circuits 17a and 17b, and the error check parts 23 and 24 of received packets which are multiplexed communication circuits. The reception propriety information of the packet is answered from the data-reception side terminal 2 to the transmission-side terminal 1 and a next transmission queue is organized with the received propriety information, thereby optimal re-transmission is performed. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for improving the reliability of wireless communication in an environment where a plurality of wireless communications coexist, or in an environment where the electromagnetic environment is poor such as a large number of electronic devices.

[0002]

2. Description of the Related Art In recent years, the need for a LAN for wirelessly connecting terminals has been increasing year by year. The wireless LAN connection has an advantage that the terminals can be easily moved and the configuration can be changed. On the other hand, there is a disadvantage that it causes external noise, interference with other electronic devices, and wireless communication using the same frequency band, and has a demerit that communication speed and communication reliability are significantly inferior to wired communication.

In order to improve noise resistance, wireless LAN uses DS
Frequency spreading by the (direct spreading) method is adopted. DS
The system is a FSK (Frequency Shift Keying: A modulation system that shifts the frequency from the center frequency according to 1, 0 of the digital signal), and then a signal that is primary-modulated by a pseudo spread signal. This is a method of modulating into a signal having a bandwidth of about 24 MHz. The frequency band uses the 2.4 GHz ISM band (2.400 to 2.4835 GHz),
14 channels are distributed with a center frequency of 5 MHz.

In contrast to the DS system, there is a spreading system called FH (frequency / hopping) system. One example of applying the FH method is Bluetooth. With Bluetooth,
Frequency band used by DS method of wireless LAN (2.400 to 2.47835G
(Hz) and spread the frequency to a wider frequency band including communication. When a device using Bluetooth approaches a DS wireless LAN, interference occurs between them. However, in the case of Bluetooth, since the same data is retransmitted using another channel (frequency) within a specific frequency region, even if interference with a wireless LAN occurs, the influence is unlikely to occur.

Generally, as a method for avoiding interference when the wireless communication receives external noise or interference from other wireless communication, a method of changing a frequency or a frequency band used for communication, an error correction or a communication method. There is a method of compensating for data loss by devising. One example of the former technology is
6-37762. Japanese Laid-Open Patent Publication No. 6-37762 discloses a wireless channel that is not used by the radar system and changes the wireless channel that should be used in order to prevent interference with a stationary wireless system such as an existing radar system. To do. As described above, the method of investigating the usage status of the surrounding wireless system and changing the frequency or the frequency band is an effective means when the frequency of the noise generated by the interference source is known and constant.

The latter method is premised on receiving a certain amount of interference, and includes a method of optimizing the size of a packet of communication data, a method of inserting an error correction code into the packet in advance, and the like. . JP-A-6-37762
In the gazette, transmission packet data is 3
A technique is disclosed in which the data is divided into three different frequencies and the weighted signals are transmitted together with parity information of different frequencies.

[0007]

When the packet of the wireless LAN is broken due to the interference with Bluetooth, the wireless LAN waits for a certain period of time and then starts the retransmission processing. For this reason, Bluetooth
When the interference with the occurs, the transfer of the wireless LAN will be significantly reduced. Further, when the influence of the interference becomes stronger, there is a problem that the wireless LAN communication is disconnected.

[0008] Further, Bluetooth is also applied to portable devices and the like, and these portable devices can easily be carried in and out of the range of use of the wireless LAN. Therefore, the interference with the wireless LAN is often temporary. It is inefficient to change the frequency range used in the existing wireless system in order to counter the interference source that exists only for a short period.

As mentioned above, Bluetooth adopts the FH method and has the characteristic of transmitting a signal in a narrow band in which the frequency fluctuates with time. Even if the frequency is changed to another frequency, the changed frequency is further changed. Interference may occur in the band as well.

Since the wireless communication device described in the above-mentioned Japanese Patent Laid-Open No. 6-37762 is intended to constantly interfere with an existing wireless system, when there is a possibility of interference, a signal is transmitted. Was canceled or the frequency band used was changed. Therefore, in the wireless communication device described in JP-A-6-37762, not only the interference with the communication system adopting the FH method is not taken into consideration, but also the work efficiency is reduced and the transfer rate of the wireless LAN is reduced. , The problem of communication loss could not be avoided.

Further, as other noises for the wireless LAN, electromagnetic noises such as lightning generated in the natural world,
There is noise from nearby electronic devices. The microwave oven uses a radio wave with a bandwidth of about 20MHz around 2.45GHz to heat the microwave. Although the leakage of radio waves from the microwave oven is a regulated amount, the intensity of the leaked radio waves from the microwave oven and the intensity of the radio wave of the wireless LAN are similar to each other in the vicinity of the microwave oven, which causes interference.

In addition, in the case of a personal computer with a basic operating frequency of about 1 GHz, the 2.4 GHz IS
Unintended radio waves are leaking to the M band. Although not operating at high frequency like a welding machine, an unintended radio wave is leaking from a device with a large transient current such as a spark. The wireless LA is also caused by these unintentionally leaking radio waves.
N has a problem that it receives interference and the transfer speed decreases or the communication is disconnected. Furthermore, radio waves are also generated by natural phenomena such as lightning and electrostatic discharge, and wireless LANs are affected by radio waves generated by these natural phenomena, although these are rare.

The present invention has a problem that a wireless communication device, such as a wireless LAN, which communicates by using a specific channel, has a low communication speed or is disconnected due to temporary external interference. To improve communication reliability.

[0014]

According to the present invention, whether or not a packet transmitted from a wireless communication unit has been successfully transmitted is acquired from a receiving device, and a retransmission mode for the packet is set according to the acquired transmission result. It is something to choose.

With such a configuration, it becomes possible to analyze the transmission result depending on the presence or absence of interference in units of packets, and select the retransmission method according to the type of interference, and perform optimum packet transmission control and speed. The drop can be minimized.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below.

FIG. 1 is a diagram showing a configuration and a data flow of a wireless communication system according to an embodiment of the present invention. In the present embodiment, the case where the number of multiplexing channels is two has been described as an example.

In FIG. 1, the wireless communication system according to the present embodiment is composed of a transmitting side terminal 1 which is a data sender and a receiving side terminal 2 which is a data receiver. Although FIG. 1 shows data communication from the transmission side terminal 1 to the reception side terminal 2, as shown in FIG. 1, both terminals have the same hardware configuration and both data transmission and reception are performed. It can be done.

The structure necessary for transmitting data from the transmitting terminal 1 will be described. The transmitting terminal is largely composed of the pace band unit 10, the radio circuits 17a and 17b, the error checking unit 16a, and the b channel information table 18. It is configured.

The baseband unit 10 converts the data 3 to be transmitted into packets and outputs the packets to the radio circuits 17a and 17b.
The radio circuits 17a and 17b transmit packets received from the baseband unit 10 using different frequency bands. Furthermore, the error check result is received from the data receiving side terminal 2 which has received the data. Channel information table 18
Is a storage unit for sequentially storing historical data in which noise is generated for each channel.

The baseband unit 10 further includes a packet conversion unit 11, transmission queues 12 and 13, and a transmission queue management table 14.
It is composed of a and b and a transmission queue management unit 15. The packet conversion unit 11 finely divides the transmission data 3 and adds a header.

The transmission queue is a memory for storing the packets in the order in which they are transmitted. In addition, send queue 1
Reference numerals 2 and 13 are each composed of two queues so that the transmission packets for two times can be stored. That is, the send queue
12 is divided into transmission queues 12a and 12b, and transmission queue 13 is 13a
And 13b.

There is also a transmission queue management table 14a, b for each transmission queue. It also has a transmission queue management unit 15 that manages these transmission queue management tables 14a and 14b.

An example of the transmission queue management tables 14a and 14b is shown in FIG. The transmission queue management tables 14a and 14b are
Information on the packet number to be transmitted and the number of retransmissions of the packet is stored for each radio circuit. The transmission queue management unit 15 determines the packet to be retransmitted and the wireless line number to be used from the received error check result, and stores it in the transmission queue management table 14. According to the information stored in the transmission queue management table 14, the packet is output from the transmission queue to the wireless circuits 17a and 17b. In addition, the transmission queue management tables 14a and 14b are configured to store not only the number of the packet to be transmitted but also the number of times the packet is retransmitted. With this configuration, the initial value of the number of retransmissions
0, the number of retransmissions corresponding to the retransmitted packet is increased by one each time retransmission is performed. The number of retransmissions can be managed by referring to the number of retransmissions. Further, the transmission queue management unit 15 can be used as a material for determining the mode at the time of retransmission.

Further, the channel information table 18 is provided with a memory for recording the communication status of each channel such as the error rate for each channel of wireless communication. An example of the channel information table 18 is shown in FIG.

In FIG. 3, channel numbers 1 to 14 are
It shows 14 channels used by IEEE802.11b (hereinafter referred to as wireless LAN). As shown in Figure 4, the wireless LAN is 2.
Uses 4GHz ISM band, center frequency is different every 5MHZ, 1
It adopts the DS method using one of the four channels.

The usage status 32 indicates the channel currently used by the radio circuits 17a and 17b. The error rate 33 at the time of previous use is a field for storing information on the probability of an error that has occurred at the time of previous use. The presence / absence 34 of communication cancellation due to interference stores information on the number of times communication is interrupted due to interference. Further, the error occurrence count 35 stores information on the number of packets in which an error has occurred in a series of transmission data.

The channel information table 18 is not only referred to by the transmission queue management unit 15 for determining the type of interference, but also stored in a non-volatile storage device such as an HD so that it can be called from the outside. Good. In that case, the system administrator can use the information as information for reconstructing the system.

Further, the configuration required for receiving data will be described using the data receiving side terminal 2. In the receiving side terminal 2, the wireless circuits 22a and 22b receive the packet.
The receiving side terminal 2 includes error check units 23a and 23b that determine whether or not the wireless circuits 22a and 22b have been able to receive the packet normally. The error check unit replies to the transmitting side terminal 1 through the radio circuits 17a and 17b whether or not all packets have been normally received.

Packets judged to be normal by the error check units 23a and 23b are sent to the baseband unit 20. The baseband unit 20 combines the received packet with other packets to obtain the original transmission data 3
Is reproduced as reception data 4.

In this way, the wireless circuit 22a of the receiving side terminal 2,
The b has not only the function of receiving but also the function of transmitting similarly to the terminal 1 on the transmitting side. The channels used for wireless communication are wireless circuits 17a and 22a.
, And the wireless circuits 17b and 22b share another channel different from the channels used by the wireless circuits 17a and 22a. For these channels, channels that do not overlap in frequency band are set so as not to cause interference.

Next, noise with respect to the wireless LAN will be described. In wireless communication that uses the DS method such as wireless LAN, interference from FH communication equipment that spreads frequency in a wider band that exists in the same band, against the band used in wireless communication There are problems such as interference from electronic devices that leak unintentional radio waves, decrease in communication speed due to interference due to natural phenomena, and communication disconnection.

First, let us consider a case where interference is caused by external noise in a band narrower than the width of the DS system channel. Figure
As shown in 5, when external noise interferes with the frequency band used in the DS system, if it is noise in a band narrower than the channel width, it interferes in one channel but interferes with the other. Not all channels. Therefore, the interference can be avoided by changing the channel used for communication from the interfering channel to the non-interfering channel and retransmitting.

Next, FIG. 6 shows how the FH method interferes with the DS method. In the states (1) and (3) of FIG. 6, there is no interference between the FH method and the DS method. On the other hand, in the state of (2), both the FH system and the DS system use the same frequency band, and interference occurs between the FH system and the DS system. When interference with the DS method occurs, the FH method uses different frequency bands at different times, so if the same packet is retransmitted on different channels at different times, interference will occur at both transmission timings, and both times will occur. You may not be able to send data. Therefore, when it interferes with FH communication, it is effective to retransmit the same packet on two or more different channels. FIG. 7 shows a diagram when a plurality of DS system channels (multiplexing) are used. As can be seen from FIG. 7, only one channel among a plurality of channels interferes at the same timing. Therefore, when interference is received from the FH communication device, it is possible to avoid the interference by multiplexing with two or more channels.

Next, let us consider interference due to radio waves leaking from other electronic devices. FIG. 8 shows a leaked radio wave from a general microwave oven, and FIG. 9 shows a leaked radio wave from an information processing device such as a personal computer.

The microwave oven leaks radio waves in a frequency band having a spread of about 20 MHz around 2.45 GHz. The information processing device leaks a plurality of radio waves in a narrow band of frequencies corresponding to harmonics of its operating frequency. In the case of a microwave oven, it generates noise in a wider band than the wireless LAN channel,
In the case of the information processing device, the noise is in a band narrower than the channel of the wireless LAN, but is different in that noise is generated in a plurality of bands. However, in both cases, interference occurs only when the electronic device is operating, the frequency of the leaked radio wave is unique to the source and rarely changes over time, and it affects multiple channels. The point to give is common. Therefore, as in the case of external noise in a narrow band or a communication device of the FH system, communication channels may be multiplexed and channel selection may be performed so that even if one channel receives interference, the other channel can communicate.

In the natural world, noise generated by lightning or electrostatic discharge spreads over a wide band, and the timing of occurrence cannot be predicted. However, whether it is lightning or electrostatic discharge, the phenomenon ends in a short time, and there is considerable time until the next occurrence. Therefore, the interference of such a natural phenomenon can be avoided by retransmitting.

From the above, the noise types are as follows: (1) Instantaneous noise in a band narrower than the wireless LAN channel (2) Bands narrower than the wireless LAN channel in a plurality of time bands Noise generated (3) Static noise generated in a band narrower than the wireless LAN channel (4) Noise that is temporarily generated in a plurality of bands narrower than the wireless LAN channel or in a wide band .

In order to avoid the influences of the FH method, the leaked radio waves from electronic devices, and the interference from the radio waves generated by a natural phenomenon in such DS communication, the wireless communication line is multiplexed by a plurality of channels. It can be seen that the problem can be solved by providing a means for retransmitting a packet at a certain time.

Next, the packet transmission procedure will be described with reference to FIG.
This will be described with reference to the flowchart of. FIG. 10 is a diagram showing a series of flows of data transfer.

First, the processing when there is no interference and no packet loss will be described. In step 201, the packet converter 11 converts the transmission data 3 into packets.

Next, the generated packets are arranged in the transmission queue and the transmission processing is performed. As for the transmission order of the transmission queues, the packets in the respective transmission queues are transmitted in the order of the transmission queues 12a and 13a and then 12b and 13b. It is also set to transmit 3 packets consecutively.

The transmission queue management unit 15 arranges the packets in the transmission queue. The transmission queue management unit 15 uses the transmission queue 12 so that the packets with packet numbers 1 to 6 are not duplicated.
Line up on a and 13a. Next, the packets with packet numbers 7 to 12 are arranged in the transmission queues 12b and 13b. FIG. 11 shows an example of this arrangement. The transmission queue management unit 15 has the transmission queue 12
It has information for managing which transmission queue of a, 13a or 12b, 13b is transmitted, and instructs the transmission queues 12, 13 which transmission queue is to be transmitted. According to this instruction, the packet is sent to the wireless circuits 17a and 17b, and transmitted from the wireless circuits 17a and 17b to the receiving side terminal 2 by radio waves (step 202).

The receiving side terminal 2 receives the packet at the radio circuits 22a and 22b (step 211). Next, error check unit 2
3a and 3b check whether there is an error in the received packet (step 212). If there is no error, the baseband unit 20 reconstructs the data as the received data from the received packet. After receiving the packet for the first time, the error check unit returns the receivability information indicating whether or not the packet was normally received to the transmitting side terminal 1 through the wireless circuits 22a and 22b (step 213).

The transmission side terminal 1 receives the reception permission / prohibition information by the radio circuits 17a and 17b and transfers it to the transmission queue management unit 15 (step 203). The transmission queue management unit 15 determines whether or not there is a transmission error from the reception availability information (step 20).
Four). Here, since the case where there is no packet loss has been described, the process proceeds to step 205.

The transmission queue management unit 15 determines whether there is a packet waiting to be transmitted (step 205). Here, it is assumed that there is a packet waiting to be transmitted, the process returns to step 202, the transmission queue to be used is changed to the transmission queues 12b and 13b, and the packet is passed from the transmission queues 12b and 13b to the wireless circuits 17a and 17b for transmission. During this time, the transmission queue management unit determines whether or not there is any packet that could not be transmitted, and arranges them in the transmission queue management table so as to transmit the next packets, packet numbers 13 to 18.

FIG. 12 shows the state of the transmission queue management table after this rearrangement. In this way, initialization of the transmission queue management tables 14a and 14b, rearrangement of the transmission queues 12 and 13, transmission of packets, reception of receivability information, transmission of the next packet in the transmission queue, and rewriting of the transmission queue management table are performed. repeat.

Next, the case where the received packet has an error will be described.

First, the case where an instantaneous noise occurs in a band narrower than the channel will be described. When transmitting data in the transmission queues 12a and 13a in the same way as the above procedure,
It is assumed that there is an error in only one packet with packet number 2. This information is transmitted from the receiving side terminal 2.
The transmission side terminal 1 receives this data by the transmission queue management unit 15 via the wireless circuit 17a. In this case, it is determined that interference has occurred due to noise in a narrow band but the interference has already ended, and only the second packet is retransmitted. FIG. 13 shows the state of the transmission queue management table after this organization. In FIG. 13, only the second packet is retransmitted with emphasis on the communication speed, and the remaining five packets are allocated to the 13th to 17th packets that have not been transmitted yet.

Next, the case where FH type noise occurs will be described. In the case of FH type noise, the first error is indistinguishable from interference due to noise in a narrow band.
Therefore, the first time is the same retransmission method as in FIG. However, if the same error occurs in different frequency regions, it is determined that the noise is caused by the FH wireless communication device. This can be determined by referring to the error history stored in the channel information table 18. The transmission queue management unit 15 updates the channel information table 18 for each channel of an error that occurred while transmitting a series of data. The update is performed per transmission, that is, in the present embodiment, when three packets are transmitted at one time, the number of errors is sequentially stored.
By referring to such an error history, it is determined that it is due to the FH wireless communication device when the channels in which narrow band noise is generated are scattered in time.

In the case of noise caused by the FH radio communication equipment, the packet in which the error has occurred is duplicated and retransmitted. FIG. 14 shows the transmission queue management table in that case. In this way, when it is determined that the noise is caused by the FH wireless communication device, the packet in which the error occurs is duplicated and retransmitted, so that the packet can be reliably transmitted without unnecessary multiplexing. It will be possible.

Conventionally, when noise is generated, the communication line is simply multiplexed and the same packet is transmitted. With such a configuration, although a plurality of channels are used, only the same amount of data as in the case of transmitting with one channel can be transmitted, and there is a demerit that the use efficiency of radio waves is deteriorated. In order to improve this demerit, in this embodiment, when interference does not occur, packets are distributed so that they do not overlap each channel, and a packet cannot be received from the receiving side, or the data of a packet is corrupted. Only when a reply that there is a reply is sent, assuming interference due to FH method, external noise or natural noise, multiple channels are multiplexed and transmitted. By this, when there is no interference, the speed can be increased by multiplexing, and when interference occurs, the multiplexing can
It is possible to obtain high reliability such that communication is not broken.

In the present embodiment, the communication is performed in a mode in which it is determined that the wireless communication device uses the FH method and then the packet that needs to be retransmitted is duplicated and retransmitted. When an error occurs due to the transmission of the above, it may be arranged carefully so that the data is duplicated and retransmitted. By doing so, there is an advantage that it is not necessary to retransmit a plurality of error packets that occur until it is determined that the error is caused by the FH wireless communication device.

Next, the case where noise continuously occurs in one channel will be described. Steps in Figure 10
Suppose that it is found in 204 that the packets with packet numbers 2, 4, and 6 have errors. Transmission queue management unit 15
Rewrites the transmission queue management table 14 so as to retransmit the second, fourth, and sixth packets. In this case, one of the two communication channels can communicate normally,
Since the other channel could not be communicated, the transmission queue management unit 15 determines that the external noise in a narrow band or the interference of the FH communication device has occurred and the interference is continuing.
In this case, it will be multiplexed and retransmitted.
The transmission queue management table 14a is rewritten so that the packet No. 6 is transmitted by both the two channels. The structure is shown in FIG. When packets of the same channel are continuously destroyed as in this example, it is determined that noise is present in this channel, the fact that communication cannot be performed due to noise is recorded in the channel information table 18, and the communication device management is performed. It is even better to notify the person.

Next, a case where an error occurs in both channels like packet numbers 3 and 4 will be described. This is considered to be a case where noise in a wide band due to a microwave oven or noise in a narrow band due to an information processing device or the like is simultaneously generated in a plurality of channels. In such a case, the broken numbers 3 and 4 are retransmitted.

In the case of noise in a wide band, means such as changing the channel is not so effective, so that retransmission is simply repeated as shown in FIG. When the retransmissions of both channels are repeated, the information of communication cancellation due to interference is written in the channel information table 18.

In the above embodiment, the case where the number of multiplexing channels is 2 has been described, but even when the number of multiplexing is n (> 2), the algorithm is the same as in the case of 2. It goes without saying that it is possible to control packets with. In addition, when the wireless communication device includes three or more wireless circuits, the wireless communication device may be multiplexed by using all the wireless circuits.
It is also possible to perform multiplexing using some wireless circuits.
In that case, the channel information table 18 is used to select a channel to be used for multiplexing.

Further, in the present embodiment, three packets are transmitted at one transmission, but in IEEE802.11b, the number of packets to be transmitted continuously can be set up to a maximum of seven. Therefore, the optimum number of continuously transmitted packets can be set by checking the correlation between the channel information table 18 and the number of continuously transmitted packets. In the present embodiment, in the case of a mode in which three packets are transmitted at one time, if an error occurs in one packet, it is determined that instantaneous noise occurs.
It is also possible to determine that an error occurs in two consecutive packets out of the seven packets transmitted at one time, which is a momentary noise occurrence.

With respect to the retransmission processing, the packet retransmission processing optimized so as not to reduce the communication speed is performed as described above. However, a method of simply transmitting the same packet to both channels without the trouble of the retransmission processing is proposed. It is possible to improve resistance to interference due to the FH method and external noise in a narrow band. In this case, the communication speed and reliability in the case of receiving the interference are improved as compared with the case without the multiplexing, but the data communication speed and the communication speed in the case without the interference are the same as those without the multiplexing.

When setting the communication channel, the error rate at the time of the past communication stored in the channel information table 18 is referred to select the channel having the highest communication quality in the environment.

The communication speed can be improved by optimizing the number of packets to be transmitted continuously. If the number of packets to be transmitted continuously is reduced, the receivability information will be received frequently, and the transfer rate will deteriorate, but the resending process can be performed immediately. On the contrary, if the number of packets to be transmitted continuously is increased, the communication speed improves, but the time lag until receiving the receivability information increases, and there are disadvantages such as the time required for packet transmission processing when many errors occur. is there. IEEE802.
In 11b, the maximum number of packets that can be transmitted continuously is limited to seven. By checking the correlation between the channel information table 18 and the number of packets to be continuously transmitted, the optimum number of packets to be continuously transmitted can be set.

[0062]

According to the present invention, it is possible to avoid and reduce problems such as external noise assumed in radio communication by radio waves and communication speed deterioration and communication disconnection due to interference due to FH communication, and optimal packet transmission control. The speed decrease can be minimized. Further, when there is no interference, it is possible to secure the speed corresponding to the number of multiplexed lines, and it is possible to increase the speed.

Further, as another effect of the present invention, by recording communication information for each communication channel, it is possible to achieve an effect such as quick response when interference occurs and setting of an optimum communication channel. You can

[Brief description of drawings]

FIG. 1 is a diagram showing a multiplexed wireless communication system.

FIG. 2 is a diagram showing a configuration of a transmission queue management table.

FIG. 3 is a diagram showing a configuration of a channel information table.

FIG. 4 is a diagram showing frequency bands of radio waves used by a wireless LAN.

FIG. 5 is a diagram illustrating interference caused by external noise in a narrow frequency band.

FIG. 6 is a diagram illustrating interference by the FH method.

FIG. 7 is a diagram illustrating a method of avoiding interference by duplexing channels.

FIG. 8 is a diagram illustrating switching of communication channels in the FH method.

FIG. 9 is a diagram illustrating a leaked radio wave from an information processing device.

FIG. 10 is a flowchart showing a processing flow of transmission.

FIG. 11 is a diagram showing an initial state of a transmission queue management table.

FIG. 12 is a diagram showing a transmission queue management table when a packet is normally transmitted.

FIG. 13 is a diagram showing a transmission queue management table when an error occurs in one of the transmitted packets.

FIG. 14 is a diagram showing a state in which the transmission queue management table is reorganized by giving priority to communication speed when an error occurs in one of the transmitted packets.

FIG. 15 is a diagram showing a state in which the transmission queue management table is reorganized when an error occurs in three of the transmitted packets.

FIG. 16 is a diagram showing a state in which the transmission queue management table is reorganized when an error occurs in two packets transmitted at the same time among the transmitted packets.

[Explanation of symbols]

1 ... Data transmission side terminal 2 ... Data receiving terminal 3 ... Transmission data 4 ... Reproduced transmission data 10/20 ・ ・ ・ Baseband 11 ... Packet converter 12/13 ... Send queue 12a / 12b / 13a / 13b ... Transmission queue 14a / 14b ・ ・ ・ Transmission queue management table 15 ... Transmission queue management unit 16a / 16b / 23a / 23b ・ ・ ・ Error check unit 17a / 17b / 22a / 22b ・ ・ ・ Wireless circuit

Claims (5)

[Claims] 1. A data conversion unit for converting transmission data into packets, a wireless communication unit for transmitting each packet divided using a plurality of channels of different frequencies, and receiving a transmission result of the transmitted packet. A wireless communication device comprising a control unit that selects a retransmission mode according to a received transmission result. 2. The wireless communication device according to claim 1,
The wireless communication device, wherein the control unit selects a retransmission mode from the number of channels and the number of packets in which a transmission error has occurred based on the transmission result. 3. The wireless communication device according to claim 1,
When the control unit determines from the transmission result that the noise caused by the interference has occurred in a narrow frequency band, the control unit retransmits the transmission error packet in a retransmission mode for multiplexing the transmission error packet. Wireless communication device. 4. In a wireless communication device for receiving a packet divided using a plurality of channels of different frequencies, a control unit that determines the reception result of the received packet for each of the different frequencies, and the control unit determines. A wireless communication device comprising a wireless communication unit for transmitting a result. 5. A wireless communication device comprising a plurality of wireless communication devices for transmitting and receiving packets divided using a plurality of channels of different frequencies, wherein the receiving side wireless communication device displays the reception result of the received packet. A transmission side wireless communication device including a control unit for identifying each of the different frequencies and a wireless communication unit for transmitting the identification result of the control unit, a data conversion unit for converting transmission data into packets, and the divided packets. Depending on the number of packets and the number of packets in which a reception error has occurred from the identification result, a wireless communication unit that transmits using a plurality of channels of different frequencies and receives the identification result transmitted by the receiving side wireless communication device. A wireless communication device comprising a control unit that selects a retransmission mode.