JPH08149113A - Data transmission reception system - Google Patents

Abstract

PURPOSE: To provide a system for deciding an operating channel efficiently when one of plural channels is in use in a radio LAN. CONSTITUTION: Priority is placed onto each of channels A-F as shown in a table (a) in advance. At first the channel A with the highest priority is used for communication, and when an error takes place, a succeeding channel B is in use. Similarly subordinate channels are sequentially selected and used as shown in tables (b), (c). The history of successful communication is registered and updated for a channel whose communication is successful as shown in a table (d). On the occurrence of an error, when a succeeding channel is in use, channels with higher frequencies of success is selected as shown in tables (e), (f) as higher priority channels.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a data transmission / reception system, and more particularly to a wireless LAN (Local Area) of a computer device.
The present invention relates to a data transmission / reception system in a communication system.

[0002]

2. Description of the Related Art A conventional wireless LAN communication system of this type is
It is used in computer devices for wireless network communication within a relatively short distance. Normally, in this type of wireless LAN communication system, communication is performed in a single frequency band, but in the vicinity of high-power devices or electronic devices that radiate a large number of electromagnetic waves, the reliability of communication is significantly reduced due to the influence of noise. To do.

As a method of solving this, there is a method of performing wireless communication using a plurality of frequency bands. For example, as proposed in Japanese Unexamined Patent Publication No. 63-276926, data transmission is performed in a plurality of frequency bands, and the receiving side detects the noise level of these received data and selects a frequency band with a low noise level. It is selected and received.

[0004]

[Problems to be Solved by the Invention] Such a conventional wireless L
In the AN communication method, since all unused channels other than the frequency finally selected remain in the operating state during communication, extra power is continuously consumed by that amount.
Further, since it is necessary to sequentially transmit signals in each frequency band to detect the noise level, there is a problem in that it is inefficient because a process until the frequency band with the lowest noise level is selected is required. .

An object of the present invention is to provide a data transmission / reception system which consumes less power and can efficiently select and determine a used frequency.

[0006]

A data transmission / reception system according to the present invention is a data transmission / reception system in which a plurality of frequency bands are selectively used to perform data transmission / reception. Priority setting means for presetting the use priority, error detection means for detecting an error occurrence of transmission / reception data in the use frequency band, and sequential use from the highest priority frequency band set in the priority setting means It includes a used frequency band setting means for transmitting and receiving data, and a control means for controlling switching of the used frequency band of the used frequency band setting means to the next priority in response to the error detection from the error detecting means. A data transmission / reception system characterized by the above is obtained.

[0007]

[Operation] The priorities of the frequency bands used are set in advance,
Start using the frequency band with the highest priority, continue to use that frequency when communication succeeds without any error in transmitted / received data, and switch to the frequency band with the next priority for communication if an error is detected. I am doing it.

[0008]

Embodiments of the present invention will be described in detail below with reference to the drawings.

FIG. 1 is a system block diagram showing an embodiment of the present invention. In the figure, a transmitting side 100 includes an environment data storage unit 1, a transmission control unit 2, a frequency changing circuit 3,
It includes a plurality of transmission channels 4 and a plurality of reception channels 5.

The environmental data storage unit 1 stores information such as channel (frequency band) priority and the number of successful communications, and at the initial stage, predetermined channel priorities are stored.

The transmission signal control unit 2 transmits the transmission data to the reception side 2.
00 is a control unit that determines whether to continuously transmit to 00 or retransmit after changing the channel, and stores the current setting in the environment data storage unit 1.

The frequency changing circuit 3 performs switching of transmission channels and modulation of transmission data under the control of the transmission signal control unit 2. The transmission channel 4 is a portion for actually transmitting a signal, and the reception channel 5 is for receiving transmission data from the receiving side 200.

The receiving side 200 has a receiving channel 6, a receiving type control section 7, a frequency changing circuit 8 and an error checking section 9.
And an environment data storage unit 10 and a transmission channel 11.

The receiving channel 6 is for receiving the data transmitted from the transmitting side 100, and the transmitting channel 11 is for transmitting the data to the transmitting side 100. Although a plurality of channels 4 and 6 are shown in the figure, this is a logical expression and is actually changed (tuned) by the frequency changing circuit 3 and is physically one. is there.

The reception signal control unit 7 demodulates the reception data and passes it to the error check unit 9. If no error is detected, the reception signal control unit 7 notifies the transmission side 100 via the frequency changing circuit 8 and the transmission channel 11, Also, the environmental data storage unit 10
Controls saving of current settings.

The error check unit 9 checks the received data for an error and reports the check result to the received signal control unit 7. The environmental data storage unit 10 stores the same data as the environmental data storage unit 10 of the transmitting side 100, and the initial values of both are set to match in advance.

The concept of the present invention will be described with reference to FIG.
FIG. 2 is a diagram showing the storage contents of the environment data storage units 1 and 10 and the subsequent content change state. In the initial stage, a plurality of channels A to F (five channels can be used) are registered in advance in descending order of priority (A to F) (see FIG. 2A).

First, when data transmission is started for the channel A having the priority level, an error check of the received data is performed on the receiving side. If no error is detected, the communication is continued as it is for the channel A, but if an error is detected, the channel B is switched to the next priority channel B, and the same process is performed thereafter (FIG. 2 (b)). ，
(C)). That is, the channels with the highest priority are used in order, and when an error is detected, the channel with the next priority is used for switching.

In this case, the number of successful communications of each used channel is checked, and the number of successful communications is recorded for each channel (see FIG. 2 (d)). When an error occurs in a certain used channel, the channel with the highest number of successes is used as the next used channel by raising it to the highest priority (see FIGS. 2E and 2F).

The operation of the embodiment of the present invention will be described below with reference to the float charts of FIGS. 3 shows the operation of the transmitting side 100, and FIG. 4 shows the operation of the receiving side 200.

First, the environment data stored in the environment data storage units 1 and 10 is read, and the highest priority channel A to be used is set. Data is transmitted and received on this channel. On the receiving side 200, the error check of the received data is performed by the error check unit 9,
If normal, the data reception completion is notified to the transmitting side 100, and the number of times of successful communication is incremented by 1 for the channel A.

When the transmission side 100 receives the data reception completion notification from the reception side 200 within a fixed time from the data transmission, it determines that the transmission is successful and increments the number of successes of the channel A by +1. Here, instead of notifying the occurrence of an error, the fact that it is notified in the normal case is that if there is an error in the transmission data and an error occurs, the probability that the error will also occur in the returned notification signal due to the influence of noise Is high.

Therefore, if there is no response within a fixed time after data transmission, the transmission side 100 regards that an error has occurred, reads environmental data for the next channel setting, and gives priority to the next channel B. Degree is the highest priority, and this channel B is used. The same applies to the receiving side 200.

If an error still occurs even if the channel is switched, the channels having lower priorities are sequentially switched, but if there is no channel in use, error processing is performed and communication becomes impossible.

By doing so, the environmental data is updated and stored sequentially, and the possibility (hit rate) of changing to a channel in which communication can be succeeded by a single switching becomes large, and wasteful channel switching is not repeated, which is short. The time channel can be set.

This is a process when communication fails (when an error occurs in all channels). However, when there are a plurality of terminals in (or in the vicinity of) the system installation environment, channels used by other terminals compete with each other to give a signal. There is a possibility that an error will occur due to interference, so it is not an error process to just make a communication failure on all channels once, but try again several times after waiting for a certain period of time. Is good.

[0027]

As described above, according to the present invention, a channel that is not affected by noise is automatically selected for signal transmission, so that it is highly reliable even in an environment severely affected by noise. The effect is that communication becomes possible.

Since the priority of the channel is learned based on the past experience, it is possible to switch to the optimum channel according to the system installation environment in a short time, improve the communication efficiency, and use it. Since there is no power consumption other than the channels, it is possible to save power.

[Brief description of drawings]

FIG. 1 is a system block diagram of an embodiment of the present invention.

FIG. 2 is a diagram showing priorities of used channels and examples of changing the priorities.

FIG. 3 is an operation flow diagram on the transmitting side.

FIG. 4 is an operation flow diagram on the receiving side.

[Explanation of symbols]

 1,10 Environmental data storage unit 2 Transmission signal control unit 3,8 Frequency changing circuit 4,11 Transmission channel 5,6 Reception channel 7 Reception signal control unit 9 Error check unit 100 Transmission side 200 Reception side

Claims (4)

[Claims] 1. A data transmission / reception system configured to selectively transmit and receive data by using a plurality of frequency bands, and a priority order setting means for presetting a use priority order of the plurality of frequency bands. An error detecting means for detecting an error occurrence of transmitted / received data in a used frequency band, and a used frequency band setting means for sequentially transmitting / receiving data from the highest priority frequency band set in the priority setting means, A data transmission / reception system, comprising: a control means for switching and controlling a use frequency band of the use frequency band setting means to the next priority in response to an error detection from the error detection means. 2. The storage device according to claim 1, further comprising a storage unit that counts the number of successes of the used frequency band for which data transmission and reception have succeeded without error detection by the error detection unit and updates and stores the count value. Data transmission / reception system. 3. The day transmission / reception system according to claim 2, wherein the priority order setting means changes and controls the priority order such that a frequency band having a larger count value has a larger priority order. 4. The data transmission / reception system according to claim 1, which is a wireless LAN communication system.