JP3100285B2 - Wireless data communication device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wireless data communication device used as a wireless station connected to a POS terminal or a host computer of a wireless POS (point of sale information) system.

[0002]

2. Description of the Related Art FIG. 7 is a schematic block diagram of a conventional general wireless POS system. The wireless POS system shown in this figure has six POS terminals 1 for registering product sales data.
a, 1b, 1c, 1d, 1e, 1f, a host computer 2 as a higher-level device for controlling two radio base stations 3
a and 3b are connected by wire, and the respective POS terminals 1a to 1b are connected.
1f, the radio stations 4a, 4b, 4c, 4d, 4
e, 4f, and wireless communication is performed between each of the wireless base stations 3a, 3b and each of the wireless slave stations 4a to 4f.
It enables data transmission and reception between the S terminals 1a to 1f and the host computer 2.

[0003] Incidentally, the POS terminals 1a to 1f are distributed and installed at each sales floor on one floor of a store, respectively, and the radio stations 4a to 4f are mounted near the corresponding POS terminals 1a to 1f, respectively. Have been. On the other hand, the host computer 2 is installed in a store office or the like,
In this state, wireless communication with each of the wireless slave stations 4a to 4f cannot be performed. Therefore, the two wireless base stations 3a and 3b are connected to each PO
By attaching the S terminals 1a to 1f to the ceiling of the floor on which the S terminals 1a to 1f are installed at an interval, wireless communication over the entire area of one floor is enabled.

[0004] Here, the POS terminals 1a to 1a are located within an area of a radio wave propagation distance where one of the radio base stations 3a can communicate stably.
c is installed, and the POS terminal 1d is located within a radio wave propagation distance range where the other wireless base station 3b can communicate stably.
If the POS terminals 1a to 1f are installed, each POS terminal 1a to 1c normally performs wireless communication with one wireless base station 3a, and the remaining POS terminals 1d to 1f normally communicate with the other wireless base station 3a.
b, the wireless parameters such as the identifier of the communication partner are communicated to each of the wireless base stations 3a and 3b and the wireless
Set up the system by setting a to 4f in advance.

[0005] By the way, as a radio communication system of such a system, a system in which a master controls transmission of a slave between a radio station serving as a master and a radio station serving as a slave, that is, a so-called polling / selecting system is generally used. A method in which each radio station transmits freely and only one station acquires the transmission right according to a certain rule such as "first come, first served";
Although there is a so-called contention method, in the case of a POS system, a high-speed response is required for unit price inquiry or the like, and therefore, a contention method excellent in high speed is often used.

[0006]

However, when the contention system is adopted as the communication system of the wireless POS system, in the environment where the traffic volume of the wireless communication is increased, for example, a store having a large sales floor is used. Like P
If the number of OS terminals is large, the number of transmission retries increases due to the deterioration of the wireless environment, or if the frequency of sales registrations increases significantly due to busy stores, it takes time to acquire the transmission right. Since the possibility is high, there is a concern that the response time to the unit price inquiry or the like may be significantly increased.

In general, in the contention system,
CSMA (Carrier Sense Multiple Access) to determine whether there is a radio carrier before transmission and avoid communication collision
Although the system is mainly used, when the traffic volume increases, the number of collisions increases, so that communication cannot be established, and there is a concern that the system may not function properly.

The present invention has been made in view of such circumstances, and an object of the present invention is to increase the traffic volume of wireless communication in a wireless data communication system employing a contention system as a wireless communication system. Even under the environment, the traffic volume of wireless communication can be reduced as much as possible, the response time for data transmission requiring response can be shortened reliably, and the system down due to the remarkable increase in traffic volume can be prevented. Another object of the present invention is to provide a wireless data communication device capable of always performing stable data communication.

[0009]

SUMMARY OF THE INVENTION According to the present invention, at the time of transmission processing of communication data, it is determined whether or not a radio line is being used by another device, and when not being used, a transmission right is acquired to transmit the communication data wirelessly. In the transmitting wireless data communication apparatus, the traffic amount measuring means for measuring the traffic amount per unit time of the wireless line and the traffic amount measured by the traffic amount measuring means prior to the communication data transmission processing are set in advance. A data transmission determining means for comparing with a threshold value to determine whether or not to perform transmission immediately; and transmitting the communication data when the determination is made that the traffic amount is equal to or less than the threshold value and the transmission is to be performed immediately. When the traffic volume exceeds the threshold and the transmission delay is determined by the communication data transmission processing means to be processed and the determination means, the communication data is processed. Communication data storage means for temporarily storing the communication data, and postponement data transmission means for transmitting the communication data stored in the communication data storage unit by the storage means when the traffic amount satisfies a communicable condition of a threshold value or less. It is provided.

The data transmission judging means has a judging means for judging whether or not the postponement is possible depending on the type of the communication data, and judges whether or not to immediately transmit only the postponable communication data based on the traffic volume. However, communication data that cannot be postponed may be transmitted immediately regardless of the traffic volume.

[0011]

According to the present invention having such a configuration, prior to transmitting communication data, the traffic amount measured by the traffic amount measuring means is compared with a preset threshold value and transmission is immediately performed. Is determined.
When the traffic amount is equal to or less than the threshold value and it is determined that the transmission is to be performed immediately, the communication data is transmitted. That is, it is determined whether or not the wireless line is in use by another device, and when not in use, a transmission right is obtained and the communication data is wirelessly transmitted. On the other hand, when the traffic volume exceeds the threshold value and transmission delay is determined, the communication data is temporarily stored in the communication data storage unit. The communication data stored in the storage unit is subjected to transmission processing when the traffic volume is reduced and the communicable condition equal to or less than the threshold is satisfied.

Therefore, when the traffic volume increases so as to exceed the threshold value, the transmission of communication data is postponed until the traffic volume decreases and the communicable condition is satisfied. An increase is prevented.

[0013] Whether or not postponement is possible is determined according to the type of communication data, and non-postponable communication data, for example, data requiring a high-speed response, is immediately transmitted regardless of the traffic volume.

[0014]

FIG. 7 shows a wireless POS system (two wireless base stations 3a and 3b, terminals 1a to 1f) according to the present invention.
An example in which the present invention is applied to each of the wireless slave stations 4a to 4f in a system including six wireless slave stations 4a to 4f) will be described with reference to the drawings.

The radio communication specifications in this embodiment are as follows: radio wave format = spread spectrum, frequency band = 2.4 G
Hz band, output = 10 mW / MHz, frequency channel = 1 wave (ch1), communication system = half duplex, spreading system = direct spreading system, data communication speed = 256 kbps.

FIG. 1 is a block diagram showing a main configuration of the host computer 2.
Is a CPU (Central Processor)
Unit) 21 and a ROM (Read Only Memory) for storing fixed data such as program data executed by the CPU 21.
ry) 22, RAM (Random Acc.) for storing variable data
ess Memory) 23, a communication interface 24 to which both wireless base stations 3a and 3b are connected by wire, a keyboard interface 25 for inputting a key signal from a keyboard 25a,
It comprises a display device interface 26 for sending display data to the CRT display device 26a.

FIG. 2 is a block diagram showing a main configuration of the POS terminal 1a.
1, a communication interface 14 to which a corresponding wireless slave station 4a is connected by wire, a keyboard interface 15 to which a key signal from a keyboard 15a is input, a receipt / journal printer, a display, a scanner, a card reader, etc., in addition to the ROM 12 and the RAM 13. Of the peripheral device 16a to which the peripheral device 16a is connected.

Since the other POS terminals 1b to 1f have the same configuration as that of FIG. 2, the following description will be made using the same reference numerals for the common parts.

FIG. 3 is a block diagram showing a main configuration of the wireless slave station 4a. The wireless slave station 4a is provided with a CPU 41, an RO
A timer controller 44 that supplies a timer interrupt signal to the CPU 41 at regular intervals, in addition to the M42 and the RAM 43;
It comprises a communication interface 45 to which the corresponding POS terminal 1a is connected, a wireless circuit section 46 for transmitting and receiving wireless data, an antenna 47 and the like.

The radio circuit section 46 supplies a communication data generated under the control of the CPU 41 to the modulation section 46b. The radio transmission section 46a modulates the communication data supplied from the radio transmission section 46a and supplies it to the antenna 47. Modulation section 46
b, a demodulation unit 46c for demodulating communication data received by the antenna 47, a radio receiving unit 46d for taking in the communication data demodulated by the demodulation unit 46, and a radio wave from the communication data demodulated by the demodulation unit 46c. It comprises a carrier sense section 46e for determining the presence or absence of a carrier.

Since the other wireless slave stations 4b to 4f have the same configuration as in FIG. 3, the following description will be made using the same reference numerals for common parts.

Now, the ROM 42 of each of the wireless slave stations 4a to 4f
In addition to a program for operating as a wireless slave station of an ordinary wireless POS system, a wireless traffic calculation program 51, a data communication determination program 52, and a postponed data transmission program 5 are provided, as shown in FIG.
3 is pre-installed.

The wireless traffic calculation program 51
Is a business program for periodically calculating wireless communication traffic defined as a wireless line usage rate per unit time.
Is stored in the ROM 42 and the CPU 41 that executes the wireless traffic calculation program 51 constitutes a traffic amount measuring unit.

Before transmitting the communication data, the data communication determination program 52 compares the traffic amount measured by the traffic amount measuring means with a preset threshold value and determines whether or not to perform transmission immediately. If the traffic volume is below the threshold value and it is determined that transmission is to be performed immediately, the communication data is processed for transmission, and the traffic volume exceeds the threshold value and transmission delay is determined relatively much. Is a business program for temporarily storing the communication data in the communication data storage unit.
And a CP that executes the data communication determination program 52
U41 constitutes a data transmission determination unit, a communication data transmission processing unit, and a communication data storage unit.

The postponement data transmission program 53 is a business program for transmitting the communication data stored in the communication data storage section by the communication data storage means when the traffic amount satisfies the communicable condition equal to or less than the threshold value. The ROM 42 storing the postponement data transmission program 53 and the postponement data transmission program 53
The postponement data transmission means is constituted by the CPU 41 executing the above.

The RAM 43 of each of the wireless slave stations 4a to 4f
In particular, as shown in FIG. 5, a communication data storage file 61 constituting the communication data storage unit, a timer interrupt counter 62 for counting the number of interrupt signal inputs t from the timer controller 44, a carrier sense unit 46e, a radio busy counter 63 for counting the number of times TW that the radio line is in use, a limit memory 64 for storing a traffic limit TR0 as a threshold value of the traffic amount, A permissible value memory 65 for storing a traffic permissible value TR1 which is a maximum value of a region which is equal to or less than a limit value TR0 and which satisfies a communication possible condition, and a calculation for storing the latest traffic calculated value TR calculated by the wireless traffic measuring means. A value memory 66;
A communication data table 67 for storing communication data names and priority flag data corresponding to the type codes for distinguishing various types of communication data is formed.

The communication data storage file 61 comprises a communication data area 61 capable of storing a plurality of communication data and a data number counter 61b for counting the number S of data stored in the communication data area 61a.

The priority flag in the communication data table 67 is a flag for setting whether or not the corresponding communication data can be postponed by the data transmission judging means, and "0" indicates that the postponement is possible. , "1" indicates that the postponement is not possible.

The CPU 41 checks the priority flag during execution of the data communication determination program 52 to determine whether or not postponement is possible. Here, the data transmission determining means constituted by the ROM 42 storing the data communication determining program 52 and the CPU 41 executing the data communication determining program 52 determines whether or not postponement is possible depending on the type of communication data. Including means.

Next, the P of the present embodiment configured as described above is
In the OS system, the operation when the wireless slave stations 4a to 4f perform wireless transmission will be described with reference to the flowcharts shown in FIGS.

FIG. 6A is a flowchart showing a main part of the wireless traffic calculation program 51, and FIG. 6B is a flowchart showing a main part of the data communication determination program 52.
(C) is a flowchart showing a main part of the postponement data transmission program.

First, as an initial condition, each radio station 4a
Communication data storage file 6 in RAM 43 in 4f to 4f
1 and the calculated value memory 66 are cleared. The count values t and Tw of the timer interrupt counter 62 and the radio busy counter 63 are both reset to "0".

In the limit value memory 64, for example, "0.7" is set in advance as the traffic limit value TR0, and in the allowable value memory 65, for example, "0.5" is set in advance as the traffic allowable value TR1. ing.

The traffic limit value TR0 and the traffic allowance value TR1 are not limited to the present embodiment.
An optimum value may be set within a practical range. However, generally, once the traffic volume increases, it often takes time to recover, so it is desirable to have a hysteresis characteristic so that TR1 <TR0.

Further, in the communication data table 67, a data name and a priority flag "0" or "1" are set corresponding to the data types of various communication data. In the present embodiment, only communication data generated in the registration of merchandise sales data performed at the POS terminals 1a to 1f is illustrated, and unit price inquiry data and credit collation data that require a high-speed response are prioritized as non-postponable data. The description is continued assuming that the flag is set to "1", and that the priority flag is reset to "0" as merchandise sales data, sales total data, credit sales data, etc., for which no response is required, as postponable data.

The unit price inquiry data is stored in the POS terminal 1
When the merchandise code of the customer purchased merchandise is entered in a to 1f, the data is used to inquire the host computer 2 about the unit price of the merchandise. Is done. The credit collation data is data for inquiring the validity of the credit card to the host computer 2 when the credit card of the credit customer is read by the POS terminals 1a to 1f. The computer 2 responds whether the credit card is valid or invalid.

On the other hand, the merchandise sales data is stored in the POS terminal 1a.
The code, sales points,
This is data for notifying the host computer 2 of the sales amount and the like, and the total sales data notifies the host computer 2 of the total points and the total amount of all the purchased goods of one shopper registered and processed by the POS terminals 1a to 1f. Data
The credit sales data is data for notifying the host computer 2 of the details of the transaction for which payment has been made by a credit card at the POS terminals 1a to 1f. No response.

The timer controller 44 has a CPU
The interrupt interval of the interrupt signal input to the interrupt terminal p is set to, for example, 50 μs, and the interrupt interval of the interrupt signal input to the interrupt terminal q is set to, for example, 1 s.

Here, the interruption interval of the interruption signal inputted to the interruption terminal p is determined by the radio traffic calculation program 51.
Is executed, and the interrupt interval of the interrupt signal input to the interrupt terminal q is an interval at which the postponement data transmission program 53 is executed.

Although the interrupt interval of these interrupt signals is not limited to the present embodiment, the shorter the interval of the interrupt signal input to the interrupt terminal p, the higher the accuracy. It is not even. However, it is preferable that the selection be made according to the performance of the CPU 41.

The CPU 41 executes the processing shown in FIG. 6A in accordance with the wireless traffic calculation program 51 every time an interrupt signal is input to the interrupt terminal p.

That is, first, the timer interrupt counter 62 is incremented by "+1" as ST (step) 1. Next, in step ST2, the wireless circuit section 46 is operated to perform carrier sensing, and if it is confirmed that the radio carrier is detected by the carrier sensing section 46e, the wireless line is being used. "+1" is counted up. If it is confirmed in ST2 that the radio wave carrier is not detected by the carrier sensing unit 46e, it means that the radio line is not in use, so that S
The processing of T3 is not performed.

Next, as ST4, the timer interrupt counter 6
It is determined whether or not the count value t of 2 has reached a value t0 corresponding to a unit time for measuring the traffic amount. And
If the count value t has not reached the value t0, the current process ends. Here, assuming that the unit time is 1 second, the value t0 is "20,000".

When the count value t reaches the value t0 in ST4, the count value TW of the radio busy counter 63 is changed to the timer interrupt counter 6 corresponding to the unit time in ST5.
The traffic amount TR per unit time is calculated by dividing by the count value t0 of 2, and the contents of the calculated value memory 66 are updated. Thereafter, if the count values t and TW of the timer interrupt counter 62 and the radio busy counter 63 are reset to "0" in ST6, the current process is terminated.

Therefore, the processing of ST1 to ST3 results in 5
The carrier sense state determined by the carrier sense unit 46e is observed at 0 μs intervals, and the number of times the wireless line is busy is counted by the wireless busy counter 63. Then, when the observation time of 1 second per unit time is detected by the processing of ST4, the ratio of the wireless use time per unit time, that is, the traffic amount per 1 second of time is measured by the processing of ST5, and the calculated value memory is stored. 66 and updated. After that, the count values t and TW of the timer interrupt counter 62 and the radio busy counter 63 are reset to "0" by the processing of ST6 to prepare for the next traffic volume measurement per unit time.

On the other hand, the CPU 41 of each of the wireless slave stations 4a to 4f
Is the POS connected via the communication interface 45
Each time a transmission request for communication data is received from the terminals 1a to 1f, the data communication determination program 52 shown in FIG.
The processing shown in (b) is executed.

That is, first, as ST11, the latest traffic amount TR per unit time per second stored in the calculated value memory 66 is compared with the traffic limit value TR0 preset in the limit value memory 64, and the traffic amount is calculated. It is determined whether or not TR exceeds the traffic limit value TR0.

If it does not exceed it, it recognizes that communication is possible, and executes data transmission processing by the contention method in ST12. That is, the wireless circuit unit 46 performs carrier sense to determine whether or not the wireless line is in use, and when not in use, acquires a transmission right and wirelessly transmits the corresponding communication data. After transmission, the current process ends.

On the other hand, if the traffic amount TR exceeds the traffic limit value TR0, it is recognized that communication is difficult, and the communication data table 6 is determined as ST13.
7, the priority flag corresponding to the type code of the communication data requested to be transmitted is read. If the priority flag is set to "1" in ST14, the communication data requested to be transmitted is data that cannot be postponed, and the process proceeds to ST12 to execute data transmission processing by the contention method.

On the other hand, if the priority flag corresponding to the type code of the communication data is reset to "0" in ST14, the communication data requested to be transmitted is data that can be postponed. File 6
1, the communication data is registered in an empty area of the communication data area 61a. If the data number counter 61b in the communication data storage file 61 has been incremented by "+1" in ST16, the current process is terminated.

Therefore, if there is a communication data transmission request when the traffic amount TR per unit time has not reached the traffic limit value TR0 by the processing of ST11 and ST12, the wireless slave station acquires the transmission right. When the wireless line is not in use and has acquired the transmission right, it is transmitted wirelessly.

On the other hand, ST11, ST13 and ST13
If the transmission of the communication data is requested when the traffic amount TR per unit time has reached the traffic limit value TR0 by the processing in step 14, it is determined whether or not the communication data is data that can be postponed. Then, in the case of communication of data that cannot be postponed, such as unit price inquiry data and credit collation data, the process waits for the wireless slave station to acquire the transmission right by the processing of ST12, and if it has, the radio station is wirelessly transmitted. .

On the other hand, merchandise sales data, total sales data,
In the case of communication of data that can be postponed, such as credit sales data, the communication data is registered in the communication data storage file 61 in the order of occurrence by the processing of ST15 and ST16, and the transmission is postponed.

The CPU 41 executes the processing shown in FIG. 6C in accordance with the postponement data transmission program 53 every time an interrupt signal is input to the interrupt terminal q.

That is, first, the data number counter 61b of the communication data storage file 61 is checked in ST21.
If the count value S is “0”, there is no communication data whose transmission has been postponed, and thus the current processing is terminated.

On the other hand, when the count value S is "1" or more, the traffic amount TR per unit time exceeds the traffic limit value TR0, and communication data whose transmission has been postponed is generated in the communication data area 61a. Since it is registered in order, the latest traffic amount TR per unit time stored in the calculated value memory 66 is stored in the allowable value memory 65 in advance in the allowable value memory 65 as ST22.
It is determined whether the traffic amount TR satisfies the communicable condition equal to or less than the traffic allowable value TR1 as compared with R1.

If the traffic amount TR exceeds the allowable traffic value TR1 and does not satisfy the communicable condition, the current processing is terminated.

On the other hand, if the traffic amount TR is equal to or less than the traffic allowable value TR1 and satisfies the communicable condition, the communication data area 61 is determined as ST23.
The oldest communication data in “a” is read, and data transmission processing by the contention method is executed. Then, after transmitting the data, if the communication data that has been transmitted is deleted from the communication data area 61a and the data number counter 61b is counted down by “−1” in ST24,
This processing ends.

Therefore, the existence of data postponed by the processing of ST21 is checked at one-second intervals. Then, if it exists, it is checked whether the traffic amount is reduced and the communicable condition is satisfied. Then, only when the communicable condition is satisfied, the postponed communication data is wirelessly transmitted in ascending order each time the wireless slave station acquires the transmission right.

As described above, according to the present embodiment, the data transmitted wirelessly from each of the POS terminals 1a to 1f to the host computer 2 is, for example, excluding a part of the data which cannot be postponed and which requires a high-speed response. During the period when the traffic amount TR per unit time exceeds the preset traffic limit value TR1, the transmission processing is not performed, and the data is stored in the communication data storage file 61 as standby data. The communication data stored in the communication data storage file 61 is sequentially transmitted by radio when the traffic volume TR decreases and the communicable condition is satisfied. Therefore, even in an environment in which the traffic volume of wireless communication increases, such as when the frequency of sales registration significantly increases due to busy times of the store,
It is possible to prevent the traffic volume of the wireless communication from significantly increasing.

As a result, the traffic amount of the wireless communication is suppressed as much as possible, so that the time spent until each of the wireless slave stations 4a to 4f obtains the transmission right is reliably reduced. Therefore, processing of data requiring a response such as a unit price inquiry can be performed at high speed, and the processing capability of the POS terminals 1a to 1f can be increased. Further, since the number of times of communication collision is reduced, the system does not go down due to communication failure.

Further, in this embodiment, a communication data table 67 capable of setting a priority flag for each type of communication data is provided, and a priority flag is set for data that cannot be postponed such as a unit price inquiry. The transmission processing is performed without delay even in the time zone where the per-traffic volume TR exceeds the traffic limit value TR0. Therefore, data requiring a high-speed response, such as a unit price inquiry, is not postponed, and the system does not fail.

When there is no data that cannot be postponed, such as data requiring a high-speed response, as a wireless data communication system, the processes of ST13 and ST14 in the data communication determination program 52 are omitted, and For all communication data transmission requests, the traffic volume TR and the traffic limit value TR0 prior to data transmission
, The data transmission may be postponed if the traffic amount TR exceeds the traffic limit value TR0. In this case, the communication data table 67 can be omitted.

In the above embodiment, the present invention is applied to the wireless slave station 4.
Although applied to a to 4f, it is needless to say that the invention is applicable to the wireless base stations 3a and 3b.

In addition, the present invention is applied to a system having one or three or more wireless base stations or a system having a different number of wireless slave stations from the present embodiment, without departing from the scope of the present invention. Of course, various modifications can be made.

[0066]

As described above in detail, according to the present invention, in a wireless data communication system employing a contention system as a wireless communication system, even in an environment where the traffic volume of the wireless communication increases, the wireless communication The traffic volume can be reduced as much as possible, the response time for the transmission of data that requires a response can be shortened reliably,
It is possible to provide a wireless data communication device that can prevent a system down due to a remarkable increase in traffic volume and can always perform stable data communication.

[Brief description of the drawings]

FIG. 1 is an exemplary block diagram of a host computer according to an embodiment of the present invention.

FIG. 2 is an exemplary block diagram of a POS terminal according to the embodiment;

FIG. 3 is an exemplary block diagram of a main part of the wireless slave station according to the embodiment;

FIG. 4 is a diagram showing a main memory area formed in a ROM of the wireless slave station.

FIG. 5 is a diagram showing a main memory area formed in a RAM of the wireless slave station.

FIG. 6 is a flowchart showing a main part of main program processing executed by a CPU of the wireless slave station.

FIG. 7 is an overall view of a general wireless POS system.

[Explanation of symbols]

 1a-1f POS terminal 2 Host computer 3a, 3b Wireless base station 4a-4f Wireless slave station 41 CPU 42 ROM 43 RAM 46 Wireless circuit section 46e Carrier sense section 51 Wireless traffic calculation program 52 ... Data communication determination program 53 ... Postponement data transmission program 61 ... Communication data storage file 67 ... Communication data table

Claims (2)

(57) [Claims] 1. A wireless data communication apparatus for determining whether or not a wireless line is in use by another device during transmission processing of communication data and acquiring a transmission right when not in use to wirelessly transmit the communication data. A traffic volume measuring unit for measuring a traffic volume per unit time of the wireless line, and comparing a traffic volume measured by the traffic volume measuring unit with a preset threshold value before transmitting the communication data. Data transmission determining means for determining whether or not to perform transmission immediately, and when the determination means determines that the traffic amount is equal to or less than the threshold value and the transmission is to be performed immediately, the communication data is transmitted. Communication data transmission processing means, and if the traffic amount exceeds the threshold value and transmission delay is determined by the determination means, Communication data storage means for temporarily storing communication data, and transmitting processing of communication data stored in the communication data storage unit by the storage means when the traffic volume satisfies a communication enabling condition of not more than the threshold value. A wireless data communication device comprising a postponement data transmission means. 2. The data transmission determining means has a determining means for determining whether or not postponement is possible according to a type of communication data, and judges whether or not to immediately transmit only postponable communication data based on a traffic amount. 2. The wireless data communication apparatus according to claim 1, wherein the communication data that cannot be postponed is immediately transmitted regardless of the traffic volume.